src/diffviewer/ydiff.c

   1 /*
   2    Copyright (C) 2007, 2010, 2011, 2012
   3    The Free Software Foundation, Inc.
   4
   5    Written by:
   6    Daniel Borca <dborca@yahoo.com>, 2007
   7    Slava Zanko <slavazanko@gmail.com>, 2010
   8    Andrew Borodin <aborodin@vmail.ru>, 2010, 2012
   9    Ilia Maslakov <il.smind@gmail.com>, 2010
  10
  11    This file is part of the Midnight Commander.
  12
  13    The Midnight Commander is free software: you can redistribute it
  14    and/or modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation, either version 3 of the License,
  16    or (at your option) any later version.
  17
  18    The Midnight Commander is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21    GNU General Public License for more details.
  22
  23    You should have received a copy of the GNU General Public License
  24    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25  */
  26
  27
  28 #include <config.h>
  29 #include <ctype.h>
  30 #include <errno.h>
  31 #include <fcntl.h>
  32 #include <stdlib.h>
  33 #include <sys/stat.h>
  34 #include <sys/types.h>
  35 #include <sys/wait.h>
  36
  37 #include "lib/global.h"
  38 #include "lib/tty/tty.h"
  39 #include "lib/tty/color.h"
  40 #include "lib/tty/key.h"
  41 #include "lib/skin.h"           /* EDITOR_NORMAL_COLOR */
  42 #include "lib/vfs/vfs.h"        /* mc_opendir, mc_readdir, mc_closedir, */
  43 #include "lib/util.h"
  44 #include "lib/widget.h"
  45 #include "lib/strutil.h"
  46 #include "lib/strescape.h"      /* strutils_glob_escape() */
  47 #ifdef HAVE_CHARSET
  48 #include "lib/charsets.h"
  49 #endif
  50 #include "lib/event.h"          /* mc_event_raise() */
  51
  52 #include "src/filemanager/cmd.h"        /* do_edit_at_line(), view_other_cmd() */
  53 #include "src/filemanager/panel.h"
  54 #include "src/filemanager/layout.h"     /* Needed for get_current_index and get_other_panel */
  55
  56 #include "src/keybind-defaults.h"
  57 #include "src/setup.h"
  58 #include "src/history.h"
  59 #ifdef HAVE_CHARSET
  60 #include "src/selcodepage.h"
  61 #endif
  62
  63 #include "ydiff.h"
  64 #include "internal.h"
  65
  66 /*** global variables ****************************************************************************/
  67
  68 /*** file scope macro definitions ****************************************************************/
  69
  70 #define g_array_foreach(a, TP, cbf) \
  71 do { \
  72     size_t g_array_foreach_i;\
  73     TP *g_array_foreach_var = NULL; \
  74     for (g_array_foreach_i = 0; g_array_foreach_i < a->len; g_array_foreach_i++) \
  75     { \
  76         g_array_foreach_var = &g_array_index (a, TP, g_array_foreach_i); \
  77         (*cbf) (g_array_foreach_var); \
  78     } \
  79 } while (0)
  80
  81 #define FILE_READ_BUF 4096
  82 #define FILE_FLAG_TEMP (1 << 0)
  83
  84 #define ADD_CH '+'
  85 #define DEL_CH '-'
  86 #define CHG_CH '*'
  87 #define EQU_CH ' '
  88
  89 #define HDIFF_ENABLE 1
  90 #define HDIFF_MINCTX 5
  91 #define HDIFF_DEPTH 10
  92
  93 #define FILE_DIRTY(fs) \
  94 do \
  95 { \
  96     (fs)->pos = 0; \
  97     (fs)->len = 0;  \
  98 } \
  99 while (0)
 100
 101 /*** file scope type declarations ****************************************************************/
 102
 103 typedef enum
 104 {
 105     FROM_LEFT_TO_RIGHT,
 106     FROM_RIGHT_TO_LEFT
 107 } action_direction_t;
 108
 109 /*** file scope variables ************************************************************************/
 110
 111 /*** file scope functions ************************************************************************/
 112 /* --------------------------------------------------------------------------------------------- */
 113
 114 static inline int
 115 TAB_SKIP (int ts, int pos)
 116 {
 117     if (ts > 0 && ts < 9)
 118         return ts - pos % ts;
 119     else
 120         return 8 - pos % 8;
 121 }
 122
 123 /* --------------------------------------------------------------------------------------------- */
 124
 125 static gboolean
 126 rewrite_backup_content (const vfs_path_t * from_file_name_vpath, const char *to_file_name)
 127 {
 128     FILE *backup_fd;
 129     char *contents;
 130     gsize length;
 131     const char *from_file_name;
 132
 133     from_file_name = vfs_path_get_by_index (from_file_name_vpath, -1)->path;
 134     if (!g_file_get_contents (from_file_name, &contents, &length, NULL))
 135         return FALSE;
 136
 137     backup_fd = fopen (to_file_name, "w");
 138     if (backup_fd == NULL)
 139     {
 140         g_free (contents);
 141         return FALSE;
 142     }
 143
 144     length = fwrite ((const void *) contents, length, 1, backup_fd);
 145
 146     fflush (backup_fd);
 147     fclose (backup_fd);
 148     g_free (contents);
 149     return TRUE;
 150 }
 151
 152 /* buffered I/O ************************************************************* */
 153
 154 /**
 155  * Try to open a temporary file.
 156  * @note the name is not altered if this function fails
 157  *
 158  * @param[out] name address of a pointer to store the temporary name
 159  * @return file descriptor on success, negative on error
 160  */
 161
 162 static int
 163 open_temp (void **name)
 164 {
 165     int fd;
 166     vfs_path_t *diff_file_name = NULL;
 167
 168     fd = mc_mkstemps (&diff_file_name, "mcdiff", NULL);
 169     if (fd == -1)
 170     {
 171         message (D_ERROR, MSG_ERROR,
 172                  _("Cannot create temporary diff file\n%s"), unix_error_string (errno));
 173         return -1;
 174     }
 175     *name = vfs_path_to_str (diff_file_name);
 176     vfs_path_free (diff_file_name);
 177     return fd;
 178 }
 179
 180 /* --------------------------------------------------------------------------------------------- */
 181
 182 /**
 183  * Alocate file structure and associate file descriptor to it.
 184  *
 185  * @param fd file descriptor
 186  * @return file structure
 187  */
 188
 189 static FBUF *
 190 f_dopen (int fd)
 191 {
 192     FBUF *fs;
 193
 194     if (fd < 0)
 195         return NULL;
 196
 197     fs = g_try_malloc (sizeof (FBUF));
 198     if (fs == NULL)
 199         return NULL;
 200
 201     fs->buf = g_try_malloc (FILE_READ_BUF);
 202     if (fs->buf == NULL)
 203     {
 204         g_free (fs);
 205         return NULL;
 206     }
 207
 208     fs->fd = fd;
 209     FILE_DIRTY (fs);
 210     fs->flags = 0;
 211     fs->data = NULL;
 212
 213     return fs;
 214 }
 215
 216 /* --------------------------------------------------------------------------------------------- */
 217
 218 /**
 219  * Free file structure without closing the file.
 220  *
 221  * @param fs file structure
 222  * @return 0 on success, non-zero on error
 223  */
 224
 225 static int
 226 f_free (FBUF * fs)
 227 {
 228     int rv = 0;
 229
 230     if (fs->flags & FILE_FLAG_TEMP)
 231     {
 232         rv = unlink (fs->data);
 233         g_free (fs->data);
 234     }
 235     g_free (fs->buf);
 236     g_free (fs);
 237     return rv;
 238 }
 239
 240 /* --------------------------------------------------------------------------------------------- */
 241
 242 /**
 243  * Open a binary temporary file in R/W mode.
 244  * @note the file will be deleted when closed
 245  *
 246  * @return file structure
 247  */
 248 static FBUF *
 249 f_temp (void)
 250 {
 251     int fd;
 252     FBUF *fs;
 253
 254     fs = f_dopen (0);
 255     if (fs == NULL)
 256         return NULL;
 257
 258     fd = open_temp (&fs->data);
 259     if (fd < 0)
 260     {
 261         f_free (fs);
 262         return NULL;
 263     }
 264
 265     fs->fd = fd;
 266     fs->flags = FILE_FLAG_TEMP;
 267     return fs;
 268 }
 269
 270 /* --------------------------------------------------------------------------------------------- */
 271
 272 /**
 273  * Open a binary file in specified mode.
 274  *
 275  * @param filename file name
 276  * @param flags open mode, a combination of O_RDONLY, O_WRONLY, O_RDWR
 277  *
 278  * @return file structure
 279  */
 280
 281 static FBUF *
 282 f_open (const char *filename, int flags)
 283 {
 284     int fd;
 285     FBUF *fs;
 286
 287     fs = f_dopen (0);
 288     if (fs == NULL)
 289         return NULL;
 290
 291     fd = open (filename, flags);
 292     if (fd < 0)
 293     {
 294         f_free (fs);
 295         return NULL;
 296     }
 297
 298     fs->fd = fd;
 299     return fs;
 300 }
 301
 302 /* --------------------------------------------------------------------------------------------- */
 303
 304 /**
 305  * Read a line of bytes from file until newline or EOF.
 306  * @note does not stop on null-byte
 307  * @note buf will not be null-terminated
 308  *
 309  * @param buf destination buffer
 310  * @param size size of buffer
 311  * @param fs file structure
 312  *
 313  * @return number of bytes read
 314  */
 315
 316 static size_t
 317 f_gets (char *buf, size_t size, FBUF * fs)
 318 {
 319     size_t j = 0;
 320
 321     do
 322     {
 323         int i;
 324         int stop = 0;
 325
 326         for (i = fs->pos; j < size && i < fs->len && !stop; i++, j++)
 327         {
 328             buf[j] = fs->buf[i];
 329             if (buf[j] == '\n')
 330                 stop = 1;
 331         }
 332         fs->pos = i;
 333
 334         if (j == size || stop)
 335             break;
 336
 337         fs->pos = 0;
 338         fs->len = read (fs->fd, fs->buf, FILE_READ_BUF);
 339     }
 340     while (fs->len > 0);
 341
 342     return j;
 343 }
 344
 345 /* --------------------------------------------------------------------------------------------- */
 346
 347 /**
 348  * Seek into file.
 349  * @note avoids thrashing read cache when possible
 350  *
 351  * @param fs file structure
 352  * @param off offset
 353  * @param whence seek directive: SEEK_SET, SEEK_CUR or SEEK_END
 354  *
 355  * @return position in file, starting from begginning
 356  */
 357
 358 static off_t
 359 f_seek (FBUF * fs, off_t off, int whence)
 360 {
 361     off_t rv;
 362
 363     if (fs->len && whence != SEEK_END)
 364     {
 365         rv = lseek (fs->fd, 0, SEEK_CUR);
 366         if (rv != -1)
 367         {
 368             if (whence == SEEK_CUR)
 369             {
 370                 whence = SEEK_SET;
 371                 off += rv - fs->len + fs->pos;
 372             }
 373             if (off - rv >= -fs->len && off - rv <= 0)
 374             {
 375                 fs->pos = fs->len + off - rv;
 376                 return off;
 377             }
 378         }
 379     }
 380
 381     rv = lseek (fs->fd, off, whence);
 382     if (rv != -1)
 383         FILE_DIRTY (fs);
 384     return rv;
 385 }
 386
 387 /* --------------------------------------------------------------------------------------------- */
 388
 389 /**
 390  * Seek to the beginning of file, thrashing read cache.
 391  *
 392  * @param fs file structure
 393  *
 394  * @return 0 if success, non-zero on error
 395  */
 396
 397 static off_t
 398 f_reset (FBUF * fs)
 399 {
 400     off_t rv;
 401
 402     rv = lseek (fs->fd, 0, SEEK_SET);
 403     if (rv != -1)
 404         FILE_DIRTY (fs);
 405     return rv;
 406 }
 407
 408 /* --------------------------------------------------------------------------------------------- */
 409
 410 /**
 411  * Write bytes to file.
 412  * @note thrashes read cache
 413  *
 414  * @param fs file structure
 415  * @param buf source buffer
 416  * @param size size of buffer
 417  *
 418  * @return number of written bytes, -1 on error
 419  */
 420
 421 static ssize_t
 422 f_write (FBUF * fs, const char *buf, size_t size)
 423 {
 424     ssize_t rv;
 425
 426     rv = write (fs->fd, buf, size);
 427     if (rv >= 0)
 428         FILE_DIRTY (fs);
 429     return rv;
 430 }
 431
 432 /* --------------------------------------------------------------------------------------------- */
 433
 434 /**
 435  * Truncate file to the current position.
 436  * @note thrashes read cache
 437  *
 438  * @param fs file structure
 439  *
 440  * @return current file size on success, negative on error
 441  */
 442
 443 static off_t
 444 f_trunc (FBUF * fs)
 445 {
 446     off_t off;
 447
 448     off = lseek (fs->fd, 0, SEEK_CUR);
 449     if (off != -1)
 450     {
 451         int rv;
 452
 453         rv = ftruncate (fs->fd, off);
 454         if (rv != 0)
 455             off = -1;
 456         else
 457             FILE_DIRTY (fs);
 458     }
 459     return off;
 460 }
 461
 462 /* --------------------------------------------------------------------------------------------- */
 463
 464 /**
 465  * Close file.
 466  * @note if this is temporary file, it is deleted
 467  *
 468  * @param fs file structure
 469  * @return 0 on success, non-zero on error
 470  */
 471
 472 static int
 473 f_close (FBUF * fs)
 474 {
 475     int rv = -1;
 476
 477     if (fs != NULL)
 478     {
 479         rv = close (fs->fd);
 480         f_free (fs);
 481     }
 482
 483     return rv;
 484 }
 485
 486 /* --------------------------------------------------------------------------------------------- */
 487
 488 /**
 489  * Create pipe stream to process.
 490  *
 491  * @param cmd shell command line
 492  * @param flags open mode, either O_RDONLY or O_WRONLY
 493  *
 494  * @return file structure
 495  */
 496
 497 static FBUF *
 498 p_open (const char *cmd, int flags)
 499 {
 500     FILE *f;
 501     FBUF *fs;
 502     const char *type = NULL;
 503
 504     if (flags == O_RDONLY)
 505         type = "r";
 506     else if (flags == O_WRONLY)
 507         type = "w";
 508
 509     if (type == NULL)
 510         return NULL;
 511
 512     fs = f_dopen (0);
 513     if (fs == NULL)
 514         return NULL;
 515
 516     f = popen (cmd, type);
 517     if (f == NULL)
 518     {
 519         f_free (fs);
 520         return NULL;
 521     }
 522
 523     fs->fd = fileno (f);
 524     fs->data = f;
 525     return fs;
 526 }
 527
 528 /* --------------------------------------------------------------------------------------------- */
 529
 530 /**
 531  * Close pipe stream.
 532  *
 533  * @param fs structure
 534  * @return 0 on success, non-zero on error
 535  */
 536
 537 static int
 538 p_close (FBUF * fs)
 539 {
 540     int rv = -1;
 541
 542     if (fs != NULL)
 543     {
 544         rv = pclose (fs->data);
 545         f_free (fs);
 546     }
 547
 548     return rv;
 549 }
 550
 551 /* --------------------------------------------------------------------------------------------- */
 552
 553 /**
 554  * Get one char (byte) from string
 555  *
 556  * @param char * str, gboolean * result
 557  * @return int as character or 0 and result == FALSE if fail
 558  */
 559
 560 static int
 561 dview_get_byte (char *str, gboolean * result)
 562 {
 563     if (str == NULL)
 564     {
 565         *result = FALSE;
 566         return 0;
 567     }
 568     *result = TRUE;
 569     return (unsigned char) *str;
 570 }
 571
 572 /* --------------------------------------------------------------------------------------------- */
 573
 574 /**
 575  * Get utf multibyte char from string
 576  *
 577  * @param char * str, int * char_width, gboolean * result
 578  * @return int as utf character or 0 and result == FALSE if fail
 579  */
 580
 581 static int
 582 dview_get_utf (char *str, int *char_width, gboolean * result)
 583 {
 584     int res = -1;
 585     gunichar ch;
 586     gchar *next_ch = NULL;
 587     int width = 0;
 588
 589     *result = TRUE;
 590
 591     if (str == NULL)
 592     {
 593         *result = FALSE;
 594         return 0;
 595     }
 596
 597     res = g_utf8_get_char_validated (str, -1);
 598
 599     if (res < 0)
 600         ch = *str;
 601     else
 602     {
 603         ch = res;
 604         /* Calculate UTF-8 char width */
 605         next_ch = g_utf8_next_char (str);
 606         if (next_ch != NULL)
 607             width = next_ch - str;
 608         else
 609             ch = 0;
 610     }
 611     *char_width = width;
 612     return ch;
 613 }
 614
 615 /* --------------------------------------------------------------------------------------------- */
 616
 617 static int
 618 dview_str_utf8_offset_to_pos (const char *text, size_t length)
 619 {
 620     ptrdiff_t result;
 621
 622     if (text == NULL || text[0] == '\0')
 623         return length;
 624
 625     if (g_utf8_validate (text, -1, NULL))
 626         result = g_utf8_offset_to_pointer (text, length) - text;
 627     else
 628     {
 629         gunichar uni;
 630         char *tmpbuf, *buffer;
 631
 632         buffer = tmpbuf = g_strdup (text);
 633         while (tmpbuf[0] != '\0')
 634         {
 635             uni = g_utf8_get_char_validated (tmpbuf, -1);
 636             if ((uni != (gunichar) (-1)) && (uni != (gunichar) (-2)))
 637                 tmpbuf = g_utf8_next_char (tmpbuf);
 638             else
 639             {
 640                 tmpbuf[0] = '.';
 641                 tmpbuf++;
 642             }
 643         }
 644         result = g_utf8_offset_to_pointer (tmpbuf, length) - tmpbuf;
 645         g_free (buffer);
 646     }
 647     return max (length, (size_t) result);
 648 }
 649
 650 /* --------------------------------------------------------------------------------------------- */
 651
 652 /* diff parse *************************************************************** */
 653
 654 /**
 655  * Read decimal number from string.
 656  *
 657  * @param[in,out] str string to parse
 658  * @param[out] n extracted number
 659  * @return 0 if success, otherwise non-zero
 660  */
 661
 662 static int
 663 scan_deci (const char **str, int *n)
 664 {
 665     const char *p = *str;
 666     char *q;
 667
 668     errno = 0;
 669     *n = strtol (p, &q, 10);
 670     if (errno != 0 || p == q)
 671         return -1;
 672     *str = q;
 673     return 0;
 674 }
 675
 676 /* --------------------------------------------------------------------------------------------- */
 677
 678 /**
 679  * Parse line for diff statement.
 680  *
 681  * @param p string to parse
 682  * @param ops list of diff statements
 683  * @return 0 if success, otherwise non-zero
 684  */
 685
 686 static int
 687 scan_line (const char *p, GArray * ops)
 688 {
 689     DIFFCMD op;
 690
 691     int f1, f2;
 692     int t1, t2;
 693     int cmd;
 694     int range;
 695
 696     /* handle the following cases:
 697      *  NUMaNUM[,NUM]
 698      *  NUM[,NUM]cNUM[,NUM]
 699      *  NUM[,NUM]dNUM
 700      * where NUM is a positive integer
 701      */
 702
 703     if (scan_deci (&p, &f1) != 0 || f1 < 0)
 704         return -1;
 705
 706     f2 = f1;
 707     range = 0;
 708     if (*p == ',')
 709     {
 710         p++;
 711         if (scan_deci (&p, &f2) != 0 || f2 < f1)
 712             return -1;
 713
 714         range = 1;
 715     }
 716
 717     cmd = *p++;
 718     if (cmd == 'a')
 719     {
 720         if (range != 0)
 721             return -1;
 722     }
 723     else if (cmd != 'c' && cmd != 'd')
 724         return -1;
 725
 726     if (scan_deci (&p, &t1) != 0 || t1 < 0)
 727         return -1;
 728
 729     t2 = t1;
 730     range = 0;
 731     if (*p == ',')
 732     {
 733         p++;
 734         if (scan_deci (&p, &t2) != 0 || t2 < t1)
 735             return -1;
 736
 737         range = 1;
 738     }
 739
 740     if (cmd == 'd' && range != 0)
 741         return -1;
 742
 743     op.a[0][0] = f1;
 744     op.a[0][1] = f2;
 745     op.cmd = cmd;
 746     op.a[1][0] = t1;
 747     op.a[1][1] = t2;
 748     g_array_append_val (ops, op);
 749     return 0;
 750 }
 751
 752 /* --------------------------------------------------------------------------------------------- */
 753
 754 /**
 755  * Parse diff output and extract diff statements.
 756  *
 757  * @param f stream to read from
 758  * @param ops list of diff statements to fill
 759  * @return positive number indicating number of hunks, otherwise negative
 760  */
 761
 762 static int
 763 scan_diff (FBUF * f, GArray * ops)
 764 {
 765     int sz;
 766     char buf[BUFSIZ];
 767
 768     while ((sz = f_gets (buf, sizeof (buf) - 1, f)) != 0)
 769     {
 770         if (isdigit (buf[0]))
 771         {
 772             if (buf[sz - 1] != '\n')
 773                 return -1;
 774
 775             buf[sz] = '\0';
 776             if (scan_line (buf, ops) != 0)
 777                 return -1;
 778
 779             continue;
 780         }
 781
 782         while (buf[sz - 1] != '\n' && (sz = f_gets (buf, sizeof (buf), f)) != 0)
 783             ;
 784     }
 785
 786     return ops->len;
 787 }
 788
 789 /* --------------------------------------------------------------------------------------------- */
 790
 791 /**
 792  * Invoke diff and extract diff statements.
 793  *
 794  * @param args extra arguments to be passed to diff
 795  * @param extra more arguments to be passed to diff
 796  * @param file1 first file to compare
 797  * @param file2 second file to compare
 798  * @param ops list of diff statements to fill
 799  *
 800  * @return positive number indicating number of hunks, otherwise negative
 801  */
 802
 803 static int
 804 dff_execute (const char *args, const char *extra, const char *file1, const char *file2,
 805              GArray * ops)
 806 {
 807     static const char *opt =
 808         " --old-group-format='%df%(f=l?:,%dl)d%dE\n'"
 809         " --new-group-format='%dea%dF%(F=L?:,%dL)\n'"
 810         " --changed-group-format='%df%(f=l?:,%dl)c%dF%(F=L?:,%dL)\n'"
 811         " --unchanged-group-format=''";
 812
 813     int rv;
 814     FBUF *f;
 815     char *cmd;
 816     int code;
 817     char *file1_esc, *file2_esc;
 818
 819     /* escape potential $ to avoid shell variable substitutions in popen() */
 820     file1_esc = strutils_shell_escape (file1);
 821     file2_esc = strutils_shell_escape (file2);
 822     cmd = g_strdup_printf ("diff %s %s %s %s %s", args, extra, opt, file1_esc, file2_esc);
 823     g_free (file1_esc);
 824     g_free (file2_esc);
 825
 826     if (cmd == NULL)
 827         return -1;
 828
 829     f = p_open (cmd, O_RDONLY);
 830     g_free (cmd);
 831
 832     if (f == NULL)
 833         return -1;
 834
 835     rv = scan_diff (f, ops);
 836     code = p_close (f);
 837
 838     if (rv < 0 || code == -1 || !WIFEXITED (code) || WEXITSTATUS (code) == 2)
 839         rv = -1;
 840
 841     return rv;
 842 }
 843
 844 /* --------------------------------------------------------------------------------------------- */
 845
 846 /**
 847  * Reparse and display file according to diff statements.
 848  *
 849  * @param ord DIFF_LEFT if 1nd file is displayed , DIFF_RIGHT if 2nd file is displayed.
 850  * @param filename file name to display
 851  * @param ops list of diff statements
 852  * @param printer printf-like function to be used for displaying
 853  * @param ctx printer context
 854  *
 855  * @return 0 if success, otherwise non-zero
 856  */
 857
 858 static int
 859 dff_reparse (diff_place_t ord, const char *filename, const GArray * ops, DFUNC printer, void *ctx)
 860 {
 861     size_t i;
 862     FBUF *f;
 863     size_t sz;
 864     char buf[BUFSIZ];
 865     int line = 0;
 866     off_t off = 0;
 867     const DIFFCMD *op;
 868     diff_place_t eff;
 869     int add_cmd;
 870     int del_cmd;
 871
 872     f = f_open (filename, O_RDONLY);
 873     if (f == NULL)
 874         return -1;
 875
 876     ord &= 1;
 877     eff = ord;
 878
 879     add_cmd = 'a';
 880     del_cmd = 'd';
 881     if (ord != 0)
 882     {
 883         add_cmd = 'd';
 884         del_cmd = 'a';
 885     }
 886 #define F1 a[eff][0]
 887 #define F2 a[eff][1]
 888 #define T1 a[ ord^1 ][0]
 889 #define T2 a[ ord^1 ][1]
 890     for (i = 0; i < ops->len; i++)
 891     {
 892         int n;
 893
 894         op = &g_array_index (ops, DIFFCMD, i);
 895         n = op->F1 - (op->cmd != add_cmd);
 896
 897         while (line < n && (sz = f_gets (buf, sizeof (buf), f)) != 0)
 898         {
 899             line++;
 900             printer (ctx, EQU_CH, line, off, sz, buf);
 901             off += sz;
 902             while (buf[sz - 1] != '\n')
 903             {
 904                 sz = f_gets (buf, sizeof (buf), f);
 905                 if (sz == 0)
 906                 {
 907                     printer (ctx, 0, 0, 0, 1, "\n");
 908                     break;
 909                 }
 910                 printer (ctx, 0, 0, 0, sz, buf);
 911                 off += sz;
 912             }
 913         }
 914
 915         if (line != n)
 916             goto err;
 917
 918         if (op->cmd == add_cmd)
 919         {
 920             n = op->T2 - op->T1 + 1;
 921             while (n != 0)
 922             {
 923                 printer (ctx, DEL_CH, 0, 0, 1, "\n");
 924                 n--;
 925             }
 926         }
 927
 928         if (op->cmd == del_cmd)
 929         {
 930             n = op->F2 - op->F1 + 1;
 931             while (n != 0 && (sz = f_gets (buf, sizeof (buf), f)) != 0)
 932             {
 933                 line++;
 934                 printer (ctx, ADD_CH, line, off, sz, buf);
 935                 off += sz;
 936                 while (buf[sz - 1] != '\n')
 937                 {
 938                     sz = f_gets (buf, sizeof (buf), f);
 939                     if (sz == 0)
 940                     {
 941                         printer (ctx, 0, 0, 0, 1, "\n");
 942                         break;
 943                     }
 944                     printer (ctx, 0, 0, 0, sz, buf);
 945                     off += sz;
 946                 }
 947                 n--;
 948             }
 949
 950             if (n != 0)
 951                 goto err;
 952         }
 953
 954         if (op->cmd == 'c')
 955         {
 956             n = op->F2 - op->F1 + 1;
 957             while (n != 0 && (sz = f_gets (buf, sizeof (buf), f)) != 0)
 958             {
 959                 line++;
 960                 printer (ctx, CHG_CH, line, off, sz, buf);
 961                 off += sz;
 962                 while (buf[sz - 1] != '\n')
 963                 {
 964                     sz = f_gets (buf, sizeof (buf), f);
 965                     if (sz == 0)
 966                     {
 967                         printer (ctx, 0, 0, 0, 1, "\n");
 968                         break;
 969                     }
 970                     printer (ctx, 0, 0, 0, sz, buf);
 971                     off += sz;
 972                 }
 973                 n--;
 974             }
 975
 976             if (n != 0)
 977                 goto err;
 978
 979             n = op->T2 - op->T1 - (op->F2 - op->F1);
 980             while (n > 0)
 981             {
 982                 printer (ctx, CHG_CH, 0, 0, 1, "\n");
 983                 n--;
 984             }
 985         }
 986     }
 987 #undef T2
 988 #undef T1
 989 #undef F2
 990 #undef F1
 991
 992     while ((sz = f_gets (buf, sizeof (buf), f)) != 0)
 993     {
 994         line++;
 995         printer (ctx, EQU_CH, line, off, sz, buf);
 996         off += sz;
 997         while (buf[sz - 1] != '\n')
 998         {
 999             sz = f_gets (buf, sizeof (buf), f);
1000             if (sz == 0)
1001             {
1002                 printer (ctx, 0, 0, 0, 1, "\n");
1003                 break;
1004             }
1005             printer (ctx, 0, 0, 0, sz, buf);
1006             off += sz;
1007         }
1008     }
1009
1010     f_close (f);
1011     return 0;
1012
1013   err:
1014     f_close (f);
1015     return -1;
1016 }
1017
1018 /* --------------------------------------------------------------------------------------------- */
1019
1020 /* horizontal diff ********************************************************** */
1021
1022 /**
1023  * Longest common substring.
1024  *
1025  * @param s first string
1026  * @param m length of first string
1027  * @param t second string
1028  * @param n length of second string
1029  * @param ret list of offsets for longest common substrings inside each string
1030  * @param min minimum length of common substrings
1031  *
1032  * @return 0 if success, nonzero otherwise
1033  */
1034
1035 static int
1036 lcsubstr (const char *s, int m, const char *t, int n, GArray * ret, int min)
1037 {
1038     int i, j;
1039     int *Lprev, *Lcurr;
1040     int z = 0;
1041
1042     if (m < min || n < min)
1043     {
1044         /* XXX early culling */
1045         return 0;
1046     }
1047
1048     Lprev = g_try_new0 (int, n + 1);
1049     if (Lprev == NULL)
1050         return -1;
1051
1052     Lcurr = g_try_new0 (int, n + 1);
1053     if (Lcurr == NULL)
1054     {
1055         g_free (Lprev);
1056         return -1;
1057     }
1058
1059     for (i = 0; i < m; i++)
1060     {
1061         int *L;
1062
1063         L = Lprev;
1064         Lprev = Lcurr;
1065         Lcurr = L;
1066 #ifdef USE_MEMSET_IN_LCS
1067         memset (Lcurr, 0, (n + 1) * sizeof (int));
1068 #endif
1069         for (j = 0; j < n; j++)
1070         {
1071 #ifndef USE_MEMSET_IN_LCS
1072             Lcurr[j + 1] = 0;
1073 #endif
1074             if (s[i] == t[j])
1075             {
1076                 int v;
1077
1078                 v = Lprev[j] + 1;
1079                 Lcurr[j + 1] = v;
1080                 if (z < v)
1081                 {
1082                     z = v;
1083                     g_array_set_size (ret, 0);
1084                 }
1085                 if (z == v && z >= min)
1086                 {
1087                     int off0, off1;
1088                     size_t k;
1089
1090                     off0 = i - z + 1;
1091                     off1 = j - z + 1;
1092
1093                     for (k = 0; k < ret->len; k++)
1094                     {
1095                         PAIR *p = (PAIR *) g_array_index (ret, PAIR, k);
1096                         if ((*p)[0] == off0 || (*p)[1] >= off1)
1097                             break;
1098                     }
1099                     if (k == ret->len)
1100                     {
1101                         PAIR p2;
1102
1103                         p2[0] = off0;
1104                         p2[1] = off1;
1105                         g_array_append_val (ret, p2);
1106                     }
1107                 }
1108             }
1109         }
1110     }
1111
1112     free (Lcurr);
1113     free (Lprev);
1114     return z;
1115 }
1116
1117 /* --------------------------------------------------------------------------------------------- */
1118
1119 /**
1120  * Scan recursively for common substrings and build ranges.
1121  *
1122  * @param s first string
1123  * @param t second string
1124  * @param bracket current limits for both of the strings
1125  * @param min minimum length of common substrings
1126  * @param hdiff list of horizontal diff ranges to fill
1127  * @param depth recursion depth
1128  *
1129  * @return 0 if success, nonzero otherwise
1130  */
1131
1132 static gboolean
1133 hdiff_multi (const char *s, const char *t, const BRACKET bracket, int min, GArray * hdiff,
1134              unsigned int depth)
1135 {
1136     BRACKET p;
1137
1138     if (depth-- != 0)
1139     {
1140         GArray *ret;
1141         BRACKET b;
1142         int len;
1143
1144         ret = g_array_new (FALSE, TRUE, sizeof (PAIR));
1145         if (ret == NULL)
1146             return FALSE;
1147
1148         len = lcsubstr (s + bracket[DIFF_LEFT].off, bracket[DIFF_LEFT].len,
1149                         t + bracket[DIFF_RIGHT].off, bracket[DIFF_RIGHT].len, ret, min);
1150         if (ret->len != 0)
1151         {
1152             size_t k = 0;
1153             const PAIR *data = (const PAIR *) &g_array_index (ret, PAIR, 0);
1154             const PAIR *data2;
1155
1156             b[DIFF_LEFT].off = bracket[DIFF_LEFT].off;
1157             b[DIFF_LEFT].len = (*data)[0];
1158             b[DIFF_RIGHT].off = bracket[DIFF_RIGHT].off;
1159             b[DIFF_RIGHT].len = (*data)[1];
1160             if (!hdiff_multi (s, t, b, min, hdiff, depth))
1161                 return FALSE;
1162
1163             for (k = 0; k < ret->len - 1; k++)
1164             {
1165                 data = (const PAIR *) &g_array_index (ret, PAIR, k);
1166                 data2 = (const PAIR *) &g_array_index (ret, PAIR, k + 1);
1167                 b[DIFF_LEFT].off = bracket[DIFF_LEFT].off + (*data)[0] + len;
1168                 b[DIFF_LEFT].len = (*data2)[0] - (*data)[0] - len;
1169                 b[DIFF_RIGHT].off = bracket[DIFF_RIGHT].off + (*data)[1] + len;
1170                 b[DIFF_RIGHT].len = (*data2)[1] - (*data)[1] - len;
1171                 if (!hdiff_multi (s, t, b, min, hdiff, depth))
1172                     return FALSE;
1173             }
1174             data = (const PAIR *) &g_array_index (ret, PAIR, k);
1175             b[DIFF_LEFT].off = bracket[DIFF_LEFT].off + (*data)[0] + len;
1176             b[DIFF_LEFT].len = bracket[DIFF_LEFT].len - (*data)[0] - len;
1177             b[DIFF_RIGHT].off = bracket[DIFF_RIGHT].off + (*data)[1] + len;
1178             b[DIFF_RIGHT].len = bracket[DIFF_RIGHT].len - (*data)[1] - len;
1179             if (!hdiff_multi (s, t, b, min, hdiff, depth))
1180                 return FALSE;
1181
1182             g_array_free (ret, TRUE);
1183             return TRUE;
1184         }
1185     }
1186
1187     p[DIFF_LEFT].off = bracket[DIFF_LEFT].off;
1188     p[DIFF_LEFT].len = bracket[DIFF_LEFT].len;
1189     p[DIFF_RIGHT].off = bracket[DIFF_RIGHT].off;
1190     p[DIFF_RIGHT].len = bracket[DIFF_RIGHT].len;
1191     g_array_append_val (hdiff, p);
1192
1193     return TRUE;
1194 }
1195
1196 /* --------------------------------------------------------------------------------------------- */
1197
1198 /**
1199  * Build list of horizontal diff ranges.
1200  *
1201  * @param s first string
1202  * @param m length of first string
1203  * @param t second string
1204  * @param n length of second string
1205  * @param min minimum length of common substrings
1206  * @param hdiff list of horizontal diff ranges to fill
1207  * @param depth recursion depth
1208  *
1209  * @return 0 if success, nonzero otherwise
1210  */
1211
1212 static gboolean
1213 hdiff_scan (const char *s, int m, const char *t, int n, int min, GArray * hdiff, unsigned int depth)
1214 {
1215     int i;
1216     BRACKET b;
1217
1218     /* dumbscan (single horizontal diff) -- does not compress whitespace */
1219     for (i = 0; i < m && i < n && s[i] == t[i]; i++)
1220         ;
1221     for (; m > i && n > i && s[m - 1] == t[n - 1]; m--, n--)
1222         ;
1223
1224     b[DIFF_LEFT].off = i;
1225     b[DIFF_LEFT].len = m - i;
1226     b[DIFF_RIGHT].off = i;
1227     b[DIFF_RIGHT].len = n - i;
1228
1229     /* smartscan (multiple horizontal diff) */
1230     return hdiff_multi (s, t, b, min, hdiff, depth);
1231 }
1232
1233 /* --------------------------------------------------------------------------------------------- */
1234
1235 /* read line **************************************************************** */
1236
1237 /**
1238  * Check if character is inside horizontal diff limits.
1239  *
1240  * @param k rank of character inside line
1241  * @param hdiff horizontal diff structure
1242  * @param ord DIFF_LEFT if reading from first file, DIFF_RIGHT if reading from 2nd file
1243  *
1244  * @return TRUE if inside hdiff limits, FALSE otherwise
1245  */
1246
1247 static gboolean
1248 is_inside (int k, GArray * hdiff, diff_place_t ord)
1249 {
1250     size_t i;
1251     BRACKET *b;
1252
1253     for (i = 0; i < hdiff->len; i++)
1254     {
1255         int start, end;
1256
1257         b = &g_array_index (hdiff, BRACKET, i);
1258         start = (*b)[ord].off;
1259         end = start + (*b)[ord].len;
1260         if (k >= start && k < end)
1261             return TRUE;
1262     }
1263     return FALSE;
1264 }
1265
1266 /* --------------------------------------------------------------------------------------------- */
1267
1268 /**
1269  * Copy 'src' to 'dst' expanding tabs.
1270  * @note The procedure returns when all bytes are consumed from 'src'
1271  *
1272  * @param dst destination buffer
1273  * @param src source buffer
1274  * @param srcsize size of src buffer
1275  * @param base virtual base of this string, needed to calculate tabs
1276  * @param ts tab size
1277  *
1278  * @return new virtual base
1279  */
1280
1281 static int
1282 cvt_cpy (char *dst, const char *src, size_t srcsize, int base, int ts)
1283 {
1284     int i;
1285
1286     for (i = 0; srcsize != 0; i++, src++, dst++, srcsize--)
1287     {
1288         *dst = *src;
1289         if (*src == '\t')
1290         {
1291             int j;
1292
1293             j = TAB_SKIP (ts, i + base);
1294             i += j - 1;
1295             while (j-- > 0)
1296                 *dst++ = ' ';
1297             dst--;
1298         }
1299     }
1300     return i + base;
1301 }
1302
1303 /* --------------------------------------------------------------------------------------------- */
1304
1305 /**
1306  * Copy 'src' to 'dst' expanding tabs.
1307  *
1308  * @param dst destination buffer
1309  * @param dstsize size of dst buffer
1310  * @param[in,out] _src source buffer
1311  * @param srcsize size of src buffer
1312  * @param base virtual base of this string, needed to calculate tabs
1313  * @param ts tab size
1314  *
1315  * @return new virtual base
1316  *
1317  * @note The procedure returns when all bytes are consumed from 'src'
1318  *       or 'dstsize' bytes are written to 'dst'
1319  * @note Upon return, 'src' points to the first unwritten character in source
1320  */
1321
1322 static int
1323 cvt_ncpy (char *dst, int dstsize, const char **_src, size_t srcsize, int base, int ts)
1324 {
1325     int i;
1326     const char *src = *_src;
1327
1328     for (i = 0; i < dstsize && srcsize != 0; i++, src++, dst++, srcsize--)
1329     {
1330         *dst = *src;
1331         if (*src == '\t')
1332         {
1333             int j;
1334
1335             j = TAB_SKIP (ts, i + base);
1336             if (j > dstsize - i)
1337                 j = dstsize - i;
1338             i += j - 1;
1339             while (j-- > 0)
1340                 *dst++ = ' ';
1341             dst--;
1342         }
1343     }
1344     *_src = src;
1345     return i + base;
1346 }
1347
1348 /* --------------------------------------------------------------------------------------------- */
1349
1350 /**
1351  * Read line from memory, converting tabs to spaces and padding with spaces.
1352  *
1353  * @param src buffer to read from
1354  * @param srcsize size of src buffer
1355  * @param dst buffer to read to
1356  * @param dstsize size of dst buffer, excluding trailing null
1357  * @param skip number of characters to skip
1358  * @param ts tab size
1359  * @param show_cr show trailing carriage return as ^M
1360  *
1361  * @return negative on error, otherwise number of bytes except padding
1362  */
1363
1364 static int
1365 cvt_mget (const char *src, size_t srcsize, char *dst, int dstsize, int skip, int ts, int show_cr)
1366 {
1367     int sz = 0;
1368
1369     if (src != NULL)
1370     {
1371         int i;
1372         char *tmp = dst;
1373         const int base = 0;
1374
1375         for (i = 0; dstsize != 0 && srcsize != 0 && *src != '\n'; i++, src++, srcsize--)
1376         {
1377             if (*src == '\t')
1378             {
1379                 int j;
1380
1381                 j = TAB_SKIP (ts, i + base);
1382                 i += j - 1;
1383                 while (j-- > 0)
1384                 {
1385                     if (skip > 0)
1386                         skip--;
1387                     else if (dstsize != 0)
1388                     {
1389                         dstsize--;
1390                         *dst++ = ' ';
1391                     }
1392                 }
1393             }
1394             else if (src[0] == '\r' && (srcsize == 1 || src[1] == '\n'))
1395             {
1396                 if (skip == 0 && show_cr)
1397                 {
1398                     if (dstsize > 1)
1399                     {
1400                         dstsize -= 2;
1401                         *dst++ = '^';
1402                         *dst++ = 'M';
1403                     }
1404                     else
1405                     {
1406                         dstsize--;
1407                         *dst++ = '.';
1408                     }
1409                 }
1410                 break;
1411             }
1412             else if (skip > 0)
1413             {
1414                 int utf_ch = 0;
1415                 gboolean res;
1416                 int w;
1417
1418                 skip--;
1419                 utf_ch = dview_get_utf ((char *) src, &w, &res);
1420                 if (w > 1)
1421                     skip += w - 1;
1422                 if (!g_unichar_isprint (utf_ch))
1423                     utf_ch = '.';
1424             }
1425             else
1426             {
1427                 dstsize--;
1428                 *dst++ = *src;
1429             }
1430         }
1431         sz = dst - tmp;
1432     }
1433     while (dstsize != 0)
1434     {
1435         dstsize--;
1436         *dst++ = ' ';
1437     }
1438     *dst = '\0';
1439     return sz;
1440 }
1441
1442 /* --------------------------------------------------------------------------------------------- */
1443
1444 /**
1445  * Read line from memory and build attribute array.
1446  *
1447  * @param src buffer to read from
1448  * @param srcsize size of src buffer
1449  * @param dst buffer to read to
1450  * @param dstsize size of dst buffer, excluding trailing null
1451  * @param skip number of characters to skip
1452  * @param ts tab size
1453  * @param show_cr show trailing carriage return as ^M
1454  * @param hdiff horizontal diff structure
1455  * @param ord DIFF_LEFT if reading from first file, DIFF_RIGHT if reading from 2nd file
1456  * @param att buffer of attributes
1457  *
1458  * @return negative on error, otherwise number of bytes except padding
1459  */
1460
1461 static int
1462 cvt_mgeta (const char *src, size_t srcsize, char *dst, int dstsize, int skip, int ts, int show_cr,
1463            GArray * hdiff, diff_place_t ord, char *att)
1464 {
1465     int sz = 0;
1466
1467     if (src != NULL)
1468     {
1469         int i, k;
1470         char *tmp = dst;
1471         const int base = 0;
1472
1473         for (i = 0, k = 0; dstsize != 0 && srcsize != 0 && *src != '\n'; i++, k++, src++, srcsize--)
1474         {
1475             if (*src == '\t')
1476             {
1477                 int j;
1478
1479                 j = TAB_SKIP (ts, i + base);
1480                 i += j - 1;
1481                 while (j-- > 0)
1482                 {
1483                     if (skip != 0)
1484                         skip--;
1485                     else if (dstsize != 0)
1486                     {
1487                         dstsize--;
1488                         *att++ = is_inside (k, hdiff, ord);
1489                         *dst++ = ' ';
1490                     }
1491                 }
1492             }
1493             else if (src[0] == '\r' && (srcsize == 1 || src[1] == '\n'))
1494             {
1495                 if (skip == 0 && show_cr)
1496                 {
1497                     if (dstsize > 1)
1498                     {
1499                         dstsize -= 2;
1500                         *att++ = is_inside (k, hdiff, ord);
1501                         *dst++ = '^';
1502                         *att++ = is_inside (k, hdiff, ord);
1503                         *dst++ = 'M';
1504                     }
1505                     else
1506                     {
1507                         dstsize--;
1508                         *att++ = is_inside (k, hdiff, ord);
1509                         *dst++ = '.';
1510                     }
1511                 }
1512                 break;
1513             }
1514             else if (skip != 0)
1515             {
1516                 int utf_ch = 0;
1517                 gboolean res;
1518                 int w;
1519
1520                 skip--;
1521                 utf_ch = dview_get_utf ((char *) src, &w, &res);
1522                 if (w > 1)
1523                     skip += w - 1;
1524                 if (!g_unichar_isprint (utf_ch))
1525                     utf_ch = '.';
1526             }
1527             else
1528             {
1529                 dstsize--;
1530                 *att++ = is_inside (k, hdiff, ord);
1531                 *dst++ = *src;
1532             }
1533         }
1534         sz = dst - tmp;
1535     }
1536     while (dstsize != 0)
1537     {
1538         dstsize--;
1539         *att++ = '\0';
1540         *dst++ = ' ';
1541     }
1542     *dst = '\0';
1543     return sz;
1544 }
1545
1546 /* --------------------------------------------------------------------------------------------- */
1547
1548 /**
1549  * Read line from file, converting tabs to spaces and padding with spaces.
1550  *
1551  * @param f file stream to read from
1552  * @param off offset of line inside file
1553  * @param dst buffer to read to
1554  * @param dstsize size of dst buffer, excluding trailing null
1555  * @param skip number of characters to skip
1556  * @param ts tab size
1557  * @param show_cr show trailing carriage return as ^M
1558  *
1559  * @return negative on error, otherwise number of bytes except padding
1560  */
1561
1562 static int
1563 cvt_fget (FBUF * f, off_t off, char *dst, size_t dstsize, int skip, int ts, int show_cr)
1564 {
1565     int base = 0;
1566     int old_base = base;
1567     size_t amount = dstsize;
1568     size_t useful, offset;
1569     size_t i;
1570     size_t sz;
1571     int lastch = '\0';
1572     const char *q = NULL;
1573     char tmp[BUFSIZ];           /* XXX capacity must be >= max{dstsize + 1, amount} */
1574     char cvt[BUFSIZ];           /* XXX capacity must be >= MAX_TAB_WIDTH * amount */
1575
1576     if (sizeof (tmp) < amount || sizeof (tmp) <= dstsize || sizeof (cvt) < 8 * amount)
1577     {
1578         /* abnormal, but avoid buffer overflow */
1579         memset (dst, ' ', dstsize);
1580         dst[dstsize] = '\0';
1581         return 0;
1582     }
1583
1584     f_seek (f, off, SEEK_SET);
1585
1586     while (skip > base)
1587     {
1588         old_base = base;
1589         sz = f_gets (tmp, amount, f);
1590         if (sz == 0)
1591             break;
1592
1593         base = cvt_cpy (cvt, tmp, sz, old_base, ts);
1594         if (cvt[base - old_base - 1] == '\n')
1595         {
1596             q = &cvt[base - old_base - 1];
1597             base = old_base + q - cvt + 1;
1598             break;
1599         }
1600     }
1601
1602     if (base < skip)
1603     {
1604         memset (dst, ' ', dstsize);
1605         dst[dstsize] = '\0';
1606         return 0;
1607     }
1608
1609     useful = base - skip;
1610     offset = skip - old_base;
1611
1612     if (useful <= dstsize)
1613     {
1614         if (useful != 0)
1615             memmove (dst, cvt + offset, useful);
1616
1617         if (q == NULL)
1618         {
1619             sz = f_gets (tmp, dstsize - useful + 1, f);
1620             if (sz != 0)
1621             {
1622                 const char *ptr = tmp;
1623
1624                 useful += cvt_ncpy (dst + useful, dstsize - useful, &ptr, sz, base, ts) - base;
1625                 if (ptr < tmp + sz)
1626                     lastch = *ptr;
1627             }
1628         }
1629         sz = useful;
1630     }
1631     else
1632     {
1633         memmove (dst, cvt + offset, dstsize);
1634         sz = dstsize;
1635         lastch = cvt[offset + dstsize];
1636     }
1637
1638     dst[sz] = lastch;
1639     for (i = 0; i < sz && dst[i] != '\n'; i++)
1640     {
1641         if (dst[i] == '\r' && dst[i + 1] == '\n')
1642         {
1643             if (show_cr)
1644             {
1645                 if (i + 1 < dstsize)
1646                 {
1647                     dst[i++] = '^';
1648                     dst[i++] = 'M';
1649                 }
1650                 else
1651                 {
1652                     dst[i++] = '*';
1653                 }
1654             }
1655             break;
1656         }
1657     }
1658
1659     for (; i < dstsize; i++)
1660         dst[i] = ' ';
1661     dst[i] = '\0';
1662     return sz;
1663 }
1664
1665 /* --------------------------------------------------------------------------------------------- */
1666 /* diff printers et al ****************************************************** */
1667
1668 static void
1669 cc_free_elt (void *elt)
1670 {
1671     DIFFLN *p = elt;
1672
1673     if (p != NULL)
1674         g_free (p->p);
1675 }
1676
1677 /* --------------------------------------------------------------------------------------------- */
1678
1679 static int
1680 printer (void *ctx, int ch, int line, off_t off, size_t sz, const char *str)
1681 {
1682     GArray *a = ((PRINTER_CTX *) ctx)->a;
1683     DSRC dsrc = ((PRINTER_CTX *) ctx)->dsrc;
1684
1685     if (ch != 0)
1686     {
1687         DIFFLN p;
1688
1689         p.p = NULL;
1690         p.ch = ch;
1691         p.line = line;
1692         p.u.off = off;
1693         if (dsrc == DATA_SRC_MEM && line != 0)
1694         {
1695             if (sz != 0 && str[sz - 1] == '\n')
1696                 sz--;
1697             if (sz > 0)
1698                 p.p = g_strndup (str, sz);
1699             p.u.len = sz;
1700         }
1701         g_array_append_val (a, p);
1702     }
1703     else if (dsrc == DATA_SRC_MEM)
1704     {
1705         DIFFLN *p;
1706
1707         p = &g_array_index (a, DIFFLN, a->len - 1);
1708         if (sz != 0 && str[sz - 1] == '\n')
1709             sz--;
1710         if (sz != 0)
1711         {
1712             size_t new_size;
1713             char *q;
1714
1715             new_size = p->u.len + sz;
1716             q = g_realloc (p->p, new_size);
1717             memcpy (q + p->u.len, str, sz);
1718             p->p = q;
1719         }
1720         p->u.len += sz;
1721     }
1722     if (dsrc == DATA_SRC_TMP && (line != 0 || ch == 0))
1723     {
1724         FBUF *f = ((PRINTER_CTX *) ctx)->f;
1725         f_write (f, str, sz);
1726     }
1727     return 0;
1728 }
1729
1730 /* --------------------------------------------------------------------------------------------- */
1731
1732 static int
1733 redo_diff (WDiff * dview)
1734 {
1735     FBUF *const *f = dview->f;
1736     PRINTER_CTX ctx;
1737     GArray *ops;
1738     int ndiff;
1739     int rv;
1740     char extra[256];
1741
1742     extra[0] = '\0';
1743     if (dview->opt.quality == 2)
1744         strcat (extra, " -d");
1745     if (dview->opt.quality == 1)
1746         strcat (extra, " --speed-large-files");
1747     if (dview->opt.strip_trailing_cr)
1748         strcat (extra, " --strip-trailing-cr");
1749     if (dview->opt.ignore_tab_expansion)
1750         strcat (extra, " -E");
1751     if (dview->opt.ignore_space_change)
1752         strcat (extra, " -b");
1753     if (dview->opt.ignore_all_space)
1754         strcat (extra, " -w");
1755     if (dview->opt.ignore_case)
1756         strcat (extra, " -i");
1757
1758     if (dview->dsrc != DATA_SRC_MEM)
1759     {
1760         f_reset (f[DIFF_LEFT]);
1761         f_reset (f[DIFF_RIGHT]);
1762     }
1763
1764     ops = g_array_new (FALSE, FALSE, sizeof (DIFFCMD));
1765     ndiff = dff_execute (dview->args, extra, dview->file[DIFF_LEFT], dview->file[DIFF_RIGHT], ops);
1766     if (ndiff < 0)
1767     {
1768         if (ops != NULL)
1769             g_array_free (ops, TRUE);
1770         return -1;
1771     }
1772
1773     ctx.dsrc = dview->dsrc;
1774
1775     rv = 0;
1776     ctx.a = dview->a[DIFF_LEFT];
1777     ctx.f = f[DIFF_LEFT];
1778     rv |= dff_reparse (DIFF_LEFT, dview->file[DIFF_LEFT], ops, printer, &ctx);
1779
1780     ctx.a = dview->a[DIFF_RIGHT];
1781     ctx.f = f[DIFF_RIGHT];
1782     rv |= dff_reparse (DIFF_RIGHT, dview->file[DIFF_RIGHT], ops, printer, &ctx);
1783
1784     if (ops != NULL)
1785         g_array_free (ops, TRUE);
1786
1787     if (rv != 0 || dview->a[DIFF_LEFT]->len != dview->a[DIFF_RIGHT]->len)
1788         return -1;
1789
1790     if (dview->dsrc == DATA_SRC_TMP)
1791     {
1792         f_trunc (f[DIFF_LEFT]);
1793         f_trunc (f[DIFF_RIGHT]);
1794     }
1795
1796     if (dview->dsrc == DATA_SRC_MEM && HDIFF_ENABLE)
1797     {
1798         dview->hdiff = g_ptr_array_new ();
1799         if (dview->hdiff != NULL)
1800         {
1801             size_t i;
1802             const DIFFLN *p;
1803             const DIFFLN *q;
1804
1805             for (i = 0; i < dview->a[DIFF_LEFT]->len; i++)
1806             {
1807                 GArray *h = NULL;
1808
1809                 p = &g_array_index (dview->a[DIFF_LEFT], DIFFLN, i);
1810                 q = &g_array_index (dview->a[DIFF_RIGHT], DIFFLN, i);
1811                 if (p->line && q->line && p->ch == CHG_CH)
1812                 {
1813                     h = g_array_new (FALSE, FALSE, sizeof (BRACKET));
1814                     if (h != NULL)
1815                     {
1816                         gboolean runresult;
1817
1818                         runresult =
1819                             hdiff_scan (p->p, p->u.len, q->p, q->u.len, HDIFF_MINCTX, h,
1820                                         HDIFF_DEPTH);
1821                         if (!runresult)
1822                         {
1823                             g_array_free (h, TRUE);
1824                             h = NULL;
1825                         }
1826                     }
1827                 }
1828                 g_ptr_array_add (dview->hdiff, h);
1829             }
1830         }
1831     }
1832     return ndiff;
1833 }
1834
1835 /* --------------------------------------------------------------------------------------------- */
1836
1837 static void
1838 destroy_hdiff (WDiff * dview)
1839 {
1840     if (dview->hdiff != NULL)
1841     {
1842         int i;
1843         int len;
1844
1845         len = dview->a[DIFF_LEFT]->len;
1846
1847         for (i = 0; i < len; i++)
1848         {
1849             GArray *h;
1850
1851             h = (GArray *) g_ptr_array_index (dview->hdiff, i);
1852             if (h != NULL)
1853                 g_array_free (h, TRUE);
1854         }
1855         g_ptr_array_free (dview->hdiff, TRUE);
1856         dview->hdiff = NULL;
1857     }
1858
1859     mc_search_free (dview->search.handle);
1860     dview->search.handle = NULL;
1861     g_free (dview->search.last_string);
1862     dview->search.last_string = NULL;
1863 }
1864
1865 /* --------------------------------------------------------------------------------------------- */
1866 /* stuff ******************************************************************** */
1867
1868 static int
1869 get_digits (unsigned int n)
1870 {
1871     int d = 1;
1872
1873     while (n /= 10)
1874         d++;
1875     return d;
1876 }
1877
1878 /* --------------------------------------------------------------------------------------------- */
1879
1880 static int
1881 get_line_numbers (const GArray * a, size_t pos, int *linenum, int *lineofs)
1882 {
1883     const DIFFLN *p;
1884
1885     *linenum = 0;
1886     *lineofs = 0;
1887
1888     if (a->len != 0)
1889     {
1890         if (pos >= a->len)
1891             pos = a->len - 1;
1892
1893         p = &g_array_index (a, DIFFLN, pos);
1894
1895         if (p->line == 0)
1896         {
1897             int n;
1898
1899             for (n = pos; n > 0; n--)
1900             {
1901                 p--;
1902                 if (p->line != 0)
1903                     break;
1904             }
1905             *lineofs = pos - n + 1;
1906         }
1907
1908         *linenum = p->line;
1909     }
1910     return 0;
1911 }
1912
1913 /* --------------------------------------------------------------------------------------------- */
1914
1915 static int
1916 calc_nwidth (const GArray ** const a)
1917 {
1918     int l1, o1;
1919     int l2, o2;
1920
1921     get_line_numbers (a[DIFF_LEFT], a[DIFF_LEFT]->len - 1, &l1, &o1);
1922     get_line_numbers (a[DIFF_RIGHT], a[DIFF_RIGHT]->len - 1, &l2, &o2);
1923     if (l1 < l2)
1924         l1 = l2;
1925     return get_digits (l1);
1926 }
1927
1928 /* --------------------------------------------------------------------------------------------- */
1929
1930 static int
1931 find_prev_hunk (const GArray * a, int pos)
1932 {
1933 #if 1
1934     while (pos > 0 && ((DIFFLN *) & g_array_index (a, DIFFLN, pos))->ch != EQU_CH)
1935         pos--;
1936     while (pos > 0 && ((DIFFLN *) & g_array_index (a, DIFFLN, pos))->ch == EQU_CH)
1937         pos--;
1938     while (pos > 0 && ((DIFFLN *) & g_array_index (a, DIFFLN, pos))->ch != EQU_CH)
1939         pos--;
1940     if (pos > 0 && (size_t) pos < a->len)
1941         pos++;
1942 #else
1943     while (pos > 0 && ((DIFFLN *) & g_array_index (a, DIFFLN, pos - 1))->ch == EQU_CH)
1944         pos--;
1945     while (pos > 0 && ((DIFFLN *) & g_array_index (a, DIFFLN, pos - 1))->ch != EQU_CH)
1946         pos--;
1947 #endif
1948
1949     return pos;
1950 }
1951
1952 /* --------------------------------------------------------------------------------------------- */
1953
1954 static size_t
1955 find_next_hunk (const GArray * a, size_t pos)
1956 {
1957     while (pos < a->len && ((DIFFLN *) & g_array_index (a, DIFFLN, pos))->ch != EQU_CH)
1958         pos++;
1959     while (pos < a->len && ((DIFFLN *) & g_array_index (a, DIFFLN, pos))->ch == EQU_CH)
1960         pos++;
1961     return pos;
1962 }
1963
1964 /* --------------------------------------------------------------------------------------------- */
1965 /**
1966  * Find start and end lines of the current hunk.
1967  *
1968  * @param dview WDiff widget
1969  * @return boolean and
1970  * start_line1 first line of current hunk (file[0])
1971  * end_line1 last line of current hunk (file[0])
1972  * start_line1 first line of current hunk (file[0])
1973  * end_line1 last line of current hunk (file[0])
1974  */
1975
1976 static int
1977 get_current_hunk (WDiff * dview, int *start_line1, int *end_line1, int *start_line2, int *end_line2)
1978 {
1979     const GArray *a0 = dview->a[DIFF_LEFT];
1980     const GArray *a1 = dview->a[DIFF_RIGHT];
1981     size_t pos;
1982     int ch;
1983     int res = 0;
1984
1985     *start_line1 = 1;
1986     *start_line2 = 1;
1987     *end_line1 = 1;
1988     *end_line2 = 1;
1989
1990     pos = dview->skip_rows;
1991     ch = ((DIFFLN *) & g_array_index (a0, DIFFLN, pos))->ch;
1992     if (ch != EQU_CH)
1993     {
1994         switch (ch)
1995         {
1996         case ADD_CH:
1997             res = DIFF_DEL;
1998             break;
1999         case DEL_CH:
2000             res = DIFF_ADD;
2001             break;
2002         case CHG_CH:
2003             res = DIFF_CHG;
2004             break;
2005         }
2006         while (pos > 0 && ((DIFFLN *) & g_array_index (a0, DIFFLN, pos))->ch != EQU_CH)
2007             pos--;
2008         if (pos > 0)
2009         {
2010             *start_line1 = ((DIFFLN *) & g_array_index (a0, DIFFLN, pos))->line + 1;
2011             *start_line2 = ((DIFFLN *) & g_array_index (a1, DIFFLN, pos))->line + 1;
2012         }
2013         pos = dview->skip_rows;
2014         while (pos < a0->len && ((DIFFLN *) & g_array_index (a0, DIFFLN, pos))->ch != EQU_CH)
2015         {
2016             int l0, l1;
2017
2018             l0 = ((DIFFLN *) & g_array_index (a0, DIFFLN, pos))->line;
2019             l1 = ((DIFFLN *) & g_array_index (a1, DIFFLN, pos))->line;
2020             if (l0 > 0)
2021                 *end_line1 = max (*start_line1, l0);
2022             if (l1 > 0)
2023                 *end_line2 = max (*start_line2, l1);
2024             pos++;
2025         }
2026     }
2027     return res;
2028 }
2029
2030 /* --------------------------------------------------------------------------------------------- */
2031 /**
2032  * Remove hunk from file.
2033  *
2034  * @param dview           WDiff widget
2035  * @param merge_file      file stream for writing data
2036  * @param from1           first line of hunk
2037  * @param to1             last line of hunk
2038  * @param merge_direction in what direction files should be merged
2039  */
2040
2041 static void
2042 dview_remove_hunk (WDiff * dview, FILE * merge_file, int from1, int to1,
2043                    action_direction_t merge_direction)
2044 {
2045     int line;
2046     char buf[BUF_10K];
2047     FILE *f0;
2048
2049     if (merge_direction == FROM_RIGHT_TO_LEFT)
2050         f0 = fopen (dview->file[DIFF_RIGHT], "r");
2051     else
2052         f0 = fopen (dview->file[DIFF_LEFT], "r");
2053
2054     line = 0;
2055     while (fgets (buf, sizeof (buf), f0) != NULL && line < from1 - 1)
2056     {
2057         line++;
2058         fputs (buf, merge_file);
2059     }
2060     while (fgets (buf, sizeof (buf), f0) != NULL)
2061     {
2062         line++;
2063         if (line >= to1)
2064             fputs (buf, merge_file);
2065     }
2066     fclose (f0);
2067 }
2068
2069 /* --------------------------------------------------------------------------------------------- */
2070 /**
2071  * Add hunk to file.
2072  *
2073  * @param dview           WDiff widget
2074  * @param merge_file      file stream for writing data
2075  * @param from1           first line of source hunk
2076  * @param from2           first line of destination hunk
2077  * @param to1             last line of source hunk
2078  * @param merge_direction in what direction files should be merged
2079  */
2080
2081 static void
2082 dview_add_hunk (WDiff * dview, FILE * merge_file, int from1, int from2, int to2,
2083                 action_direction_t merge_direction)
2084 {
2085     int line;
2086     char buf[BUF_10K];
2087     FILE *f0;
2088     FILE *f1;
2089
2090     if (merge_direction == FROM_RIGHT_TO_LEFT)
2091     {
2092         f0 = fopen (dview->file[DIFF_RIGHT], "r");
2093         f1 = fopen (dview->file[DIFF_LEFT], "r");
2094     }
2095     else
2096     {
2097         f0 = fopen (dview->file[DIFF_LEFT], "r");
2098         f1 = fopen (dview->file[DIFF_RIGHT], "r");
2099     }
2100
2101     line = 0;
2102     while (fgets (buf, sizeof (buf), f0) != NULL && line < from1 - 1)
2103     {
2104         line++;
2105         fputs (buf, merge_file);
2106     }
2107     line = 0;
2108     while (fgets (buf, sizeof (buf), f1) != NULL && line <= to2)
2109     {
2110         line++;
2111         if (line >= from2)
2112             fputs (buf, merge_file);
2113     }
2114     while (fgets (buf, sizeof (buf), f0) != NULL)
2115         fputs (buf, merge_file);
2116
2117     fclose (f0);
2118     fclose (f1);
2119 }
2120
2121 /* --------------------------------------------------------------------------------------------- */
2122 /**
2123  * Replace hunk in file.
2124  *
2125  * @param dview           WDiff widget
2126  * @param merge_file      file stream for writing data
2127  * @param from1           first line of source hunk
2128  * @param to1             last line of source hunk
2129  * @param from2           first line of destination hunk
2130  * @param to2             last line of destination hunk
2131  * @param merge_direction in what direction files should be merged
2132  */
2133
2134 static void
2135 dview_replace_hunk (WDiff * dview, FILE * merge_file, int from1, int to1, int from2, int to2,
2136                     action_direction_t merge_direction)
2137 {
2138     int line1 = 0, line2 = 0;
2139     char buf[BUF_10K];
2140     FILE *f0;
2141     FILE *f1;
2142
2143     if (merge_direction == FROM_RIGHT_TO_LEFT)
2144     {
2145         f0 = fopen (dview->file[DIFF_RIGHT], "r");
2146         f1 = fopen (dview->file[DIFF_LEFT], "r");
2147     }
2148     else
2149     {
2150         f0 = fopen (dview->file[DIFF_LEFT], "r");
2151         f1 = fopen (dview->file[DIFF_RIGHT], "r");
2152     }
2153
2154     while (fgets (buf, sizeof (buf), f0) != NULL && line1 < from1 - 1)
2155     {
2156         line1++;
2157         fputs (buf, merge_file);
2158     }
2159     while (fgets (buf, sizeof (buf), f1) != NULL && line2 <= to2)
2160     {
2161         line2++;
2162         if (line2 >= from2)
2163             fputs (buf, merge_file);
2164     }
2165     while (fgets (buf, sizeof (buf), f0) != NULL)
2166     {
2167         line1++;
2168         if (line1 > to1)
2169             fputs (buf, merge_file);
2170     }
2171     fclose (f0);
2172     fclose (f1);
2173 }
2174
2175 /* --------------------------------------------------------------------------------------------- */
2176 /**
2177  * Merge hunk.
2178  *
2179  * @param dview           WDiff widget
2180  * @param merge_direction in what direction files should be merged
2181  */
2182
2183 static void
2184 do_merge_hunk (WDiff * dview, action_direction_t merge_direction)
2185 {
2186     int from1, to1, from2, to2;
2187     int hunk;
2188     diff_place_t n_merge = (merge_direction == FROM_RIGHT_TO_LEFT) ? DIFF_RIGHT : DIFF_LEFT;
2189
2190     if (merge_direction == FROM_RIGHT_TO_LEFT)
2191         hunk = get_current_hunk (dview, &from2, &to2, &from1, &to1);
2192     else
2193         hunk = get_current_hunk (dview, &from1, &to1, &from2, &to2);
2194
2195     if (hunk > 0)
2196     {
2197         int merge_file_fd;
2198         FILE *merge_file;
2199         vfs_path_t *merge_file_name_vpath = NULL;
2200
2201         if (!dview->merged[n_merge])
2202         {
2203             dview->merged[n_merge] = mc_util_make_backup_if_possible (dview->file[n_merge], "~~~");
2204             if (!dview->merged[n_merge])
2205             {
2206                 message (D_ERROR, MSG_ERROR,
2207                          _("Cannot create backup file\n%s%s\n%s"),
2208                          dview->file[n_merge], "~~~", unix_error_string (errno));
2209                 return;
2210             }
2211         }
2212
2213         merge_file_fd = mc_mkstemps (&merge_file_name_vpath, "mcmerge", NULL);
2214         if (merge_file_fd == -1)
2215         {
2216             message (D_ERROR, MSG_ERROR, _("Cannot create temporary merge file\n%s"),
2217                      unix_error_string (errno));
2218             return;
2219         }
2220
2221         merge_file = fdopen (merge_file_fd, "w");
2222
2223         switch (hunk)
2224         {
2225         case DIFF_DEL:
2226             if (merge_direction == FROM_RIGHT_TO_LEFT)
2227                 dview_add_hunk (dview, merge_file, from1, from2, to2, FROM_RIGHT_TO_LEFT);
2228             else
2229                 dview_remove_hunk (dview, merge_file, from1, to1, FROM_LEFT_TO_RIGHT);
2230             break;
2231         case DIFF_ADD:
2232             if (merge_direction == FROM_RIGHT_TO_LEFT)
2233                 dview_remove_hunk (dview, merge_file, from1, to1, FROM_RIGHT_TO_LEFT);
2234             else
2235                 dview_add_hunk (dview, merge_file, from1, from2, to2, FROM_LEFT_TO_RIGHT);
2236             break;
2237         case DIFF_CHG:
2238             dview_replace_hunk (dview, merge_file, from1, to1, from2, to2, merge_direction);
2239             break;
2240         }
2241         fflush (merge_file);
2242         fclose (merge_file);
2243         {
2244             int res;
2245
2246             res = rewrite_backup_content (merge_file_name_vpath, dview->file[n_merge]);
2247             (void) res;
2248         }
2249         mc_unlink (merge_file_name_vpath);
2250         vfs_path_free (merge_file_name_vpath);
2251     }
2252 }
2253
2254 /* --------------------------------------------------------------------------------------------- */
2255 /* view routines and callbacks ********************************************** */
2256
2257 static void
2258 dview_compute_split (WDiff * dview, int i)
2259 {
2260     dview->bias += i;
2261     if (dview->bias < 2 - dview->half1)
2262         dview->bias = 2 - dview->half1;
2263     if (dview->bias > dview->half2 - 2)
2264         dview->bias = dview->half2 - 2;
2265 }
2266
2267 /* --------------------------------------------------------------------------------------------- */
2268
2269 static void
2270 dview_compute_areas (WDiff * dview)
2271 {
2272     dview->height = LINES - 2;
2273     dview->half1 = COLS / 2;
2274     dview->half2 = COLS - dview->half1;
2275
2276     dview_compute_split (dview, 0);
2277 }
2278
2279 /* --------------------------------------------------------------------------------------------- */
2280
2281 static void
2282 dview_reread (WDiff * dview)
2283 {
2284     int ndiff;
2285
2286     destroy_hdiff (dview);
2287     if (dview->a[DIFF_LEFT] != NULL)
2288     {
2289         g_array_foreach (dview->a[DIFF_LEFT], DIFFLN, cc_free_elt);
2290         g_array_free (dview->a[DIFF_LEFT], TRUE);
2291     }
2292     if (dview->a[DIFF_RIGHT] != NULL)
2293     {
2294         g_array_foreach (dview->a[DIFF_RIGHT], DIFFLN, cc_free_elt);
2295         g_array_free (dview->a[DIFF_RIGHT], TRUE);
2296     }
2297
2298     dview->a[DIFF_LEFT] = g_array_new (FALSE, FALSE, sizeof (DIFFLN));
2299     dview->a[DIFF_RIGHT] = g_array_new (FALSE, FALSE, sizeof (DIFFLN));
2300
2301     ndiff = redo_diff (dview);
2302     if (ndiff >= 0)
2303         dview->ndiff = ndiff;
2304 }
2305
2306 /* --------------------------------------------------------------------------------------------- */
2307
2308 #ifdef HAVE_CHARSET
2309 static void
2310 dview_set_codeset (WDiff * dview)
2311 {
2312     const char *encoding_id = NULL;
2313
2314     dview->utf8 = TRUE;
2315     encoding_id =
2316         get_codepage_id (mc_global.source_codepage >=
2317                          0 ? mc_global.source_codepage : mc_global.display_codepage);
2318     if (encoding_id != NULL)
2319     {
2320         GIConv conv;
2321
2322         conv = str_crt_conv_from (encoding_id);
2323         if (conv != INVALID_CONV)
2324         {
2325             if (dview->converter != str_cnv_from_term)
2326                 str_close_conv (dview->converter);
2327             dview->converter = conv;
2328         }
2329         dview->utf8 = (gboolean) str_isutf8 (encoding_id);
2330     }
2331 }
2332
2333 /* --------------------------------------------------------------------------------------------- */
2334
2335 static void
2336 dview_select_encoding (WDiff * dview)
2337 {
2338     if (do_select_codepage ())
2339         dview_set_codeset (dview);
2340     dview_reread (dview);
2341     tty_touch_screen ();
2342     repaint_screen ();
2343 }
2344 #endif /* HAVE_CHARSET */
2345
2346 /* --------------------------------------------------------------------------------------------- */
2347
2348 static void
2349 dview_diff_options (WDiff * dview)
2350 {
2351     const char *quality_str[] = {
2352         N_("No&rmal"),
2353         N_("&Fastest (Assume large files)"),
2354         N_("&Minimal (Find a smaller set of change)")
2355     };
2356
2357     quick_widget_t quick_widgets[] = {
2358         /* *INDENT-OFF* */
2359         QUICK_START_GROUPBOX (N_("Diff algorithm")),
2360             QUICK_RADIO (3, (const char **) quality_str, (int *) &dview->opt.quality, NULL),
2361         QUICK_STOP_GROUPBOX,
2362         QUICK_START_GROUPBOX (N_("Diff extra options")),
2363             QUICK_CHECKBOX (N_("&Ignore case"), &dview->opt.ignore_case, NULL),
2364             QUICK_CHECKBOX (N_("Ignore tab &expansion"), &dview->opt.ignore_tab_expansion, NULL),
2365             QUICK_CHECKBOX (N_("Ignore &space change"), &dview->opt.ignore_space_change, NULL),
2366             QUICK_CHECKBOX (N_("Ignore all &whitespace"), &dview->opt.ignore_all_space, NULL),
2367             QUICK_CHECKBOX (N_("Strip &trailing carriage return"), &dview->opt.strip_trailing_cr,
2368                             NULL),
2369         QUICK_STOP_GROUPBOX,
2370         QUICK_BUTTONS_OK_CANCEL,
2371         QUICK_END
2372         /* *INDENT-ON* */
2373     };
2374
2375     quick_dialog_t qdlg = {
2376         -1, -1, 56,
2377         N_("Diff Options"), "[Diff Options]",
2378         quick_widgets, NULL, NULL
2379     };
2380
2381     if (quick_dialog (&qdlg) != B_CANCEL)
2382         dview_reread (dview);
2383 }
2384
2385 /* --------------------------------------------------------------------------------------------- */
2386
2387 static int
2388 dview_init (WDiff * dview, const char *args, const char *file1, const char *file2,
2389             const char *label1, const char *label2, DSRC dsrc)
2390 {
2391     int ndiff;
2392     FBUF *f[DIFF_COUNT];
2393
2394     f[DIFF_LEFT] = NULL;
2395     f[DIFF_RIGHT] = NULL;
2396
2397     if (dsrc == DATA_SRC_TMP)
2398     {
2399         f[DIFF_LEFT] = f_temp ();
2400         if (f[DIFF_LEFT] == NULL)
2401             return -1;
2402
2403         f[DIFF_RIGHT] = f_temp ();
2404         if (f[DIFF_RIGHT] == NULL)
2405         {
2406             f_close (f[DIFF_LEFT]);
2407             return -1;
2408         }
2409     }
2410     else if (dsrc == DATA_SRC_ORG)
2411     {
2412         f[DIFF_LEFT] = f_open (file1, O_RDONLY);
2413         if (f[DIFF_LEFT] == NULL)
2414             return -1;
2415
2416         f[DIFF_RIGHT] = f_open (file2, O_RDONLY);
2417         if (f[DIFF_RIGHT] == NULL)
2418         {
2419             f_close (f[DIFF_LEFT]);
2420             return -1;
2421         }
2422     }
2423
2424     dview->args = args;
2425     dview->file[DIFF_LEFT] = file1;
2426     dview->file[DIFF_RIGHT] = file2;
2427     dview->label[DIFF_LEFT] = g_strdup (label1);
2428     dview->label[DIFF_RIGHT] = g_strdup (label2);
2429     dview->f[DIFF_LEFT] = f[0];
2430     dview->f[DIFF_RIGHT] = f[1];
2431     dview->merged[DIFF_LEFT] = FALSE;
2432     dview->merged[DIFF_RIGHT] = FALSE;
2433     dview->hdiff = NULL;
2434     dview->dsrc = dsrc;
2435     dview->converter = str_cnv_from_term;
2436 #ifdef HAVE_CHARSET
2437     dview_set_codeset (dview);
2438 #endif
2439     dview->a[DIFF_LEFT] = g_array_new (FALSE, FALSE, sizeof (DIFFLN));
2440     dview->a[DIFF_RIGHT] = g_array_new (FALSE, FALSE, sizeof (DIFFLN));
2441
2442     ndiff = redo_diff (dview);
2443     if (ndiff < 0)
2444     {
2445         /* goto MSG_DESTROY stage: dview_fini() */
2446         f_close (f[DIFF_LEFT]);
2447         f_close (f[DIFF_RIGHT]);
2448         return -1;
2449     }
2450
2451     dview->ndiff = ndiff;
2452
2453     dview->view_quit = 0;
2454
2455     dview->bias = 0;
2456     dview->new_frame = 1;
2457     dview->skip_rows = 0;
2458     dview->skip_cols = 0;
2459     dview->display_symbols = 0;
2460     dview->display_numbers = 0;
2461     dview->show_cr = 1;
2462     dview->tab_size = 8;
2463     dview->ord = DIFF_LEFT;
2464     dview->full = 0;
2465
2466     dview->search.handle = NULL;
2467     dview->search.last_string = NULL;
2468     dview->search.last_found_line = -1;
2469     dview->search.last_accessed_num_line = -1;
2470
2471     dview->opt.quality = 0;
2472     dview->opt.strip_trailing_cr = 0;
2473     dview->opt.ignore_tab_expansion = 0;
2474     dview->opt.ignore_space_change = 0;
2475     dview->opt.ignore_all_space = 0;
2476     dview->opt.ignore_case = 0;
2477
2478     dview_compute_areas (dview);
2479
2480     return 0;
2481 }
2482
2483 /* --------------------------------------------------------------------------------------------- */
2484
2485 static void
2486 dview_fini (WDiff * dview)
2487 {
2488     if (dview->dsrc != DATA_SRC_MEM)
2489     {
2490         f_close (dview->f[DIFF_RIGHT]);
2491         f_close (dview->f[DIFF_LEFT]);
2492     }
2493
2494     if (dview->converter != str_cnv_from_term)
2495         str_close_conv (dview->converter);
2496
2497     destroy_hdiff (dview);
2498     if (dview->a[DIFF_LEFT] != NULL)
2499     {
2500         g_array_foreach (dview->a[DIFF_LEFT], DIFFLN, cc_free_elt);
2501         g_array_free (dview->a[DIFF_LEFT], TRUE);
2502         dview->a[DIFF_LEFT] = NULL;
2503     }
2504     if (dview->a[DIFF_RIGHT] != NULL)
2505     {
2506         g_array_foreach (dview->a[DIFF_RIGHT], DIFFLN, cc_free_elt);
2507         g_array_free (dview->a[DIFF_RIGHT], TRUE);
2508         dview->a[DIFF_RIGHT] = NULL;
2509     }
2510
2511     g_free (dview->label[DIFF_LEFT]);
2512     g_free (dview->label[DIFF_RIGHT]);
2513 }
2514
2515 /* --------------------------------------------------------------------------------------------- */
2516
2517 static int
2518 dview_display_file (const WDiff * dview, diff_place_t ord, int r, int c, int height, int width)
2519 {
2520     size_t i, k;
2521     int j;
2522     char buf[BUFSIZ];
2523     FBUF *f = dview->f[ord];
2524     int skip = dview->skip_cols;
2525     int display_symbols = dview->display_symbols;
2526     int display_numbers = dview->display_numbers;
2527     int show_cr = dview->show_cr;
2528     int tab_size = 8;
2529     const DIFFLN *p;
2530     int nwidth = display_numbers;
2531     int xwidth;
2532
2533     xwidth = display_symbols + display_numbers;
2534     if (dview->tab_size > 0 && dview->tab_size < 9)
2535         tab_size = dview->tab_size;
2536
2537     if (xwidth != 0)
2538     {
2539         if (xwidth > width && display_symbols)
2540         {
2541             xwidth--;
2542             display_symbols = 0;
2543         }
2544         if (xwidth > width && display_numbers)
2545         {
2546             xwidth = width;
2547             display_numbers = width;
2548         }
2549
2550         xwidth++;
2551         c += xwidth;
2552         width -= xwidth;
2553         if (width < 0)
2554             width = 0;
2555     }
2556
2557     if ((int) sizeof (buf) <= width || (int) sizeof (buf) <= nwidth)
2558     {
2559         /* abnormal, but avoid buffer overflow */
2560         return -1;
2561     }
2562
2563     for (i = dview->skip_rows, j = 0; i < dview->a[ord]->len && j < height; j++, i++)
2564     {
2565         int ch, next_ch, col;
2566         size_t cnt;
2567
2568         p = (DIFFLN *) & g_array_index (dview->a[ord], DIFFLN, i);
2569         ch = p->ch;
2570         tty_setcolor (NORMAL_COLOR);
2571         if (display_symbols)
2572         {
2573             tty_gotoyx (r + j, c - 2);
2574             tty_print_char (ch);
2575         }
2576         if (p->line != 0)
2577         {
2578             if (display_numbers)
2579             {
2580                 tty_gotoyx (r + j, c - xwidth);
2581                 g_snprintf (buf, display_numbers + 1, "%*d", nwidth, p->line);
2582                 tty_print_string (str_fit_to_term (buf, nwidth, J_LEFT_FIT));
2583             }
2584             if (ch == ADD_CH)
2585                 tty_setcolor (DFF_ADD_COLOR);
2586             if (ch == CHG_CH)
2587                 tty_setcolor (DFF_CHG_COLOR);
2588             if (f == NULL)
2589             {
2590                 if (i == (size_t) dview->search.last_found_line)
2591                     tty_setcolor (MARKED_SELECTED_COLOR);
2592                 else if (dview->hdiff != NULL && g_ptr_array_index (dview->hdiff, i) != NULL)
2593                 {
2594                     char att[BUFSIZ];
2595
2596                     if (dview->utf8)
2597                         k = dview_str_utf8_offset_to_pos (p->p, width);
2598                     else
2599                         k = width;
2600
2601                     cvt_mgeta (p->p, p->u.len, buf, k, skip, tab_size, show_cr,
2602                                g_ptr_array_index (dview->hdiff, i), ord, att);
2603                     tty_gotoyx (r + j, c);
2604                     col = 0;
2605
2606                     for (cnt = 0; cnt < strlen (buf) && col < width; cnt++)
2607                     {
2608                         int w;
2609                         gboolean ch_res;
2610
2611                         if (dview->utf8)
2612                         {
2613                             next_ch = dview_get_utf (buf + cnt, &w, &ch_res);
2614                             if (w > 1)
2615                                 cnt += w - 1;
2616                             if (!g_unichar_isprint (next_ch))
2617                                 next_ch = '.';
2618                         }
2619                         else
2620                             next_ch = dview_get_byte (buf + cnt, &ch_res);
2621
2622                         if (ch_res)
2623                         {
2624                             tty_setcolor (att[cnt] ? DFF_CHH_COLOR : DFF_CHG_COLOR);
2625 #ifdef HAVE_CHARSET
2626                             if (mc_global.utf8_display)
2627                             {
2628                                 if (!dview->utf8)
2629                                 {
2630                                     next_ch =
2631                                         convert_from_8bit_to_utf_c ((unsigned char) next_ch,
2632                                                                     dview->converter);
2633                                 }
2634                             }
2635                             else if (dview->utf8)
2636                                 next_ch = convert_from_utf_to_current_c (next_ch, dview->converter);
2637                             else
2638                                 next_ch = convert_to_display_c (next_ch);
2639 #endif
2640                             tty_print_anychar (next_ch);
2641                             col++;
2642                         }
2643                     }
2644                     continue;
2645                 }
2646
2647                 if (ch == CHG_CH)
2648                     tty_setcolor (DFF_CHH_COLOR);
2649
2650                 if (dview->utf8)
2651                     k = dview_str_utf8_offset_to_pos (p->p, width);
2652                 else
2653                     k = width;
2654                 cvt_mget (p->p, p->u.len, buf, k, skip, tab_size, show_cr);
2655             }
2656             else
2657                 cvt_fget (f, p->u.off, buf, width, skip, tab_size, show_cr);
2658         }
2659         else
2660         {
2661             if (display_numbers)
2662             {
2663                 tty_gotoyx (r + j, c - xwidth);
2664                 memset (buf, ' ', display_numbers);
2665                 buf[display_numbers] = '\0';
2666                 tty_print_string (buf);
2667             }
2668             if (ch == DEL_CH)
2669                 tty_setcolor (DFF_DEL_COLOR);
2670             if (ch == CHG_CH)
2671                 tty_setcolor (DFF_CHD_COLOR);
2672             memset (buf, ' ', width);
2673             buf[width] = '\0';
2674         }
2675         tty_gotoyx (r + j, c);
2676         /* tty_print_nstring (buf, width); */
2677         col = 0;
2678         for (cnt = 0; cnt < strlen (buf) && col < width; cnt++)
2679         {
2680             int w;
2681             gboolean ch_res;
2682
2683             if (dview->utf8)
2684             {
2685                 next_ch = dview_get_utf (buf + cnt, &w, &ch_res);
2686                 if (w > 1)
2687                     cnt += w - 1;
2688                 if (!g_unichar_isprint (next_ch))
2689                     next_ch = '.';
2690             }
2691             else
2692                 next_ch = dview_get_byte (buf + cnt, &ch_res);
2693             if (ch_res)
2694             {
2695 #ifdef HAVE_CHARSET
2696                 if (mc_global.utf8_display)
2697                 {
2698                     if (!dview->utf8)
2699                     {
2700                         next_ch =
2701                             convert_from_8bit_to_utf_c ((unsigned char) next_ch, dview->converter);
2702                     }
2703                 }
2704                 else if (dview->utf8)
2705                     next_ch = convert_from_utf_to_current_c (next_ch, dview->converter);
2706                 else
2707                     next_ch = convert_to_display_c (next_ch);
2708 #endif
2709
2710                 tty_print_anychar (next_ch);
2711                 col++;
2712             }
2713         }
2714     }
2715     tty_setcolor (NORMAL_COLOR);
2716     k = width;
2717     if (width < xwidth - 1)
2718         k = xwidth - 1;
2719     memset (buf, ' ', k);
2720     buf[k] = '\0';
2721     for (; j < height; j++)
2722     {
2723         if (xwidth != 0)
2724         {
2725             tty_gotoyx (r + j, c - xwidth);
2726             /* tty_print_nstring (buf, xwidth - 1); */
2727             tty_print_string (str_fit_to_term (buf, xwidth - 1, J_LEFT_FIT));
2728         }
2729         tty_gotoyx (r + j, c);
2730         /* tty_print_nstring (buf, width); */
2731         tty_print_string (str_fit_to_term (buf, width, J_LEFT_FIT));
2732     }
2733
2734     return 0;
2735 }
2736
2737 /* --------------------------------------------------------------------------------------------- */
2738
2739 static void
2740 dview_status (const WDiff * dview, diff_place_t ord, int width, int c)
2741 {
2742     const char *buf;
2743     int filename_width;
2744     int linenum, lineofs;
2745     vfs_path_t *vpath;
2746     char *path;
2747
2748     tty_setcolor (STATUSBAR_COLOR);
2749
2750     tty_gotoyx (0, c);
2751     get_line_numbers (dview->a[ord], dview->skip_rows, &linenum, &lineofs);
2752
2753     filename_width = width - 24;
2754     if (filename_width < 8)
2755         filename_width = 8;
2756
2757     vpath = vfs_path_from_str (dview->label[ord]);
2758     path = vfs_path_to_str_flags (vpath, 0, VPF_STRIP_HOME | VPF_STRIP_PASSWORD);
2759     vfs_path_free (vpath);
2760     buf = str_term_trim (path, filename_width);
2761     if (ord == DIFF_LEFT)
2762         tty_printf ("%s%-*s %6d+%-4d Col %-4d ", dview->merged[ord] ? "* " : "  ", filename_width,
2763                     buf, linenum, lineofs, dview->skip_cols);
2764     else
2765         tty_printf ("%s%-*s %6d+%-4d Dif %-4d ", dview->merged[ord] ? "* " : "  ", filename_width,
2766                     buf, linenum, lineofs, dview->ndiff);
2767     g_free (path);
2768 }
2769
2770 /* --------------------------------------------------------------------------------------------- */
2771
2772 static void
2773 dview_redo (WDiff * dview)
2774 {
2775     if (dview->display_numbers)
2776     {
2777         int old;
2778
2779         old = dview->display_numbers;
2780         dview->display_numbers = calc_nwidth ((const GArray **) dview->a);
2781         dview->new_frame = (old != dview->display_numbers);
2782     }
2783     dview_reread (dview);
2784 }
2785
2786 /* --------------------------------------------------------------------------------------------- */
2787
2788 static void
2789 dview_update (WDiff * dview)
2790 {
2791     int height = dview->height;
2792     int width1;
2793     int width2;
2794     int last;
2795
2796     last = dview->a[DIFF_LEFT]->len - 1;
2797
2798     if (dview->skip_rows > last)
2799         dview->skip_rows = dview->search.last_accessed_num_line = last;
2800     if (dview->skip_rows < 0)
2801         dview->skip_rows = dview->search.last_accessed_num_line = 0;
2802     if (dview->skip_cols < 0)
2803         dview->skip_cols = 0;
2804
2805     if (height < 2)
2806         return;
2807
2808     width1 = dview->half1 + dview->bias;
2809     width2 = dview->half2 - dview->bias;
2810     if (dview->full)
2811     {
2812         width1 = COLS;
2813         width2 = 0;
2814     }
2815
2816     if (dview->new_frame)
2817     {
2818         int xwidth;
2819
2820         tty_setcolor (NORMAL_COLOR);
2821         xwidth = dview->display_symbols + dview->display_numbers;
2822         if (width1 > 1)
2823             tty_draw_box (1, 0, height, width1, FALSE);
2824         if (width2 > 1)
2825             tty_draw_box (1, width1, height, width2, FALSE);
2826
2827         if (xwidth != 0)
2828         {
2829             xwidth++;
2830             if (xwidth < width1 - 1)
2831             {
2832                 tty_gotoyx (1, xwidth);
2833                 tty_print_alt_char (mc_tty_frm[MC_TTY_FRM_DTOPMIDDLE], FALSE);
2834                 tty_gotoyx (height, xwidth);
2835                 tty_print_alt_char (mc_tty_frm[MC_TTY_FRM_DBOTTOMMIDDLE], FALSE);
2836                 tty_draw_vline (2, xwidth, mc_tty_frm[MC_TTY_FRM_VERT], height - 2);
2837             }
2838             if (xwidth < width2 - 1)
2839             {
2840                 tty_gotoyx (1, width1 + xwidth);
2841                 tty_print_alt_char (mc_tty_frm[MC_TTY_FRM_DTOPMIDDLE], FALSE);
2842                 tty_gotoyx (height, width1 + xwidth);
2843                 tty_print_alt_char (mc_tty_frm[MC_TTY_FRM_DBOTTOMMIDDLE], FALSE);
2844                 tty_draw_vline (2, width1 + xwidth, mc_tty_frm[MC_TTY_FRM_VERT], height - 2);
2845             }
2846         }
2847         dview->new_frame = 0;
2848     }
2849
2850     if (width1 > 2)
2851     {
2852         dview_status (dview, dview->ord, width1, 0);
2853         dview_display_file (dview, dview->ord, 2, 1, height - 2, width1 - 2);
2854     }
2855     if (width2 > 2)
2856     {
2857         dview_status (dview, dview->ord ^ 1, width2, width1);
2858         dview_display_file (dview, dview->ord ^ 1, 2, width1 + 1, height - 2, width2 - 2);
2859     }
2860 }
2861
2862 /* --------------------------------------------------------------------------------------------- */
2863
2864 static void
2865 dview_edit (WDiff * dview, diff_place_t ord)
2866 {
2867     WDialog *h;
2868     gboolean h_modal;
2869     int linenum, lineofs;
2870
2871     if (dview->dsrc == DATA_SRC_TMP)
2872     {
2873         error_dialog (_("Edit"), _("Edit is disabled"));
2874         return;
2875     }
2876
2877     h = WIDGET (dview)->owner;
2878     h_modal = h->modal;
2879
2880     get_line_numbers (dview->a[ord], dview->skip_rows, &linenum, &lineofs);
2881     h->modal = TRUE;            /* not allow edit file in several editors */
2882     {
2883         vfs_path_t *tmp_vpath;
2884
2885         tmp_vpath = vfs_path_from_str (dview->file[ord]);
2886         do_edit_at_line (tmp_vpath, use_internal_edit, linenum);
2887         vfs_path_free (tmp_vpath);
2888     }
2889     h->modal = h_modal;
2890     dview_redo (dview);
2891     dview_update (dview);
2892 }
2893
2894 /* --------------------------------------------------------------------------------------------- */
2895
2896 static void
2897 dview_goto_cmd (WDiff * dview, diff_place_t ord)
2898 {
2899     /* *INDENT-OFF* */
2900     static const char *title[2] = {
2901         N_("Goto line (left)"),
2902         N_("Goto line (right)")
2903     };
2904     /* *INDENT-ON* */
2905     static char prev[256];
2906     /* XXX some statics here, to be remembered between runs */
2907
2908     int newline;
2909     char *input;
2910
2911     input = input_dialog (_(title[ord]), _("Enter line:"), MC_HISTORY_YDIFF_GOTO_LINE, prev);
2912     if (input != NULL)
2913     {
2914         const char *s = input;
2915
2916         if (scan_deci (&s, &newline) == 0 && *s == '\0')
2917         {
2918             size_t i = 0;
2919
2920             if (newline > 0)
2921             {
2922                 const DIFFLN *p;
2923
2924                 for (; i < dview->a[ord]->len; i++)
2925                 {
2926                     p = &g_array_index (dview->a[ord], DIFFLN, i);
2927                     if (p->line == newline)
2928                         break;
2929                 }
2930             }
2931             dview->skip_rows = dview->search.last_accessed_num_line = (ssize_t) i;
2932             g_snprintf (prev, sizeof (prev), "%d", newline);
2933         }
2934         g_free (input);
2935     }
2936 }
2937
2938 /* --------------------------------------------------------------------------------------------- */
2939
2940 static void
2941 dview_labels (WDiff * dview)
2942 {
2943     Widget *d;
2944     WDialog *h;
2945     WButtonBar *b;
2946
2947     d = WIDGET (dview);
2948     h = d->owner;
2949     b = find_buttonbar (h);
2950
2951     buttonbar_set_label (b, 1, Q_ ("ButtonBar|Help"), diff_map, d);
2952     buttonbar_set_label (b, 2, Q_ ("ButtonBar|Save"), diff_map, d);
2953     buttonbar_set_label (b, 4, Q_ ("ButtonBar|Edit"), diff_map, d);
2954     buttonbar_set_label (b, 5, Q_ ("ButtonBar|Merge"), diff_map, d);
2955     buttonbar_set_label (b, 7, Q_ ("ButtonBar|Search"), diff_map, d);
2956     buttonbar_set_label (b, 9, Q_ ("ButtonBar|Options"), diff_map, d);
2957     buttonbar_set_label (b, 10, Q_ ("ButtonBar|Quit"), diff_map, d);
2958 }
2959
2960 /* --------------------------------------------------------------------------------------------- */
2961
2962 static int
2963 dview_event (Gpm_Event * event, void *data)
2964 {
2965     WDiff *dview = (WDiff *) data;
2966
2967     if (!mouse_global_in_widget (event, data))
2968         return MOU_UNHANDLED;
2969
2970     /* We are not interested in release events */
2971     if ((event->type & (GPM_DOWN | GPM_DRAG)) == 0)
2972         return MOU_NORMAL;
2973
2974     /* Wheel events */
2975     if ((event->buttons & GPM_B_UP) != 0 && (event->type & GPM_DOWN) != 0)
2976     {
2977         dview->skip_rows -= 2;
2978         dview->search.last_accessed_num_line = dview->skip_rows;
2979         dview_update (dview);
2980     }
2981     else if ((event->buttons & GPM_B_DOWN) != 0 && (event->type & GPM_DOWN) != 0)
2982     {
2983         dview->skip_rows += 2;
2984         dview->search.last_accessed_num_line = dview->skip_rows;
2985         dview_update (dview);
2986     }
2987
2988     return MOU_NORMAL;
2989 }
2990
2991 /* --------------------------------------------------------------------------------------------- */
2992
2993 static gboolean
2994 dview_save (WDiff * dview)
2995 {
2996     gboolean res = TRUE;
2997
2998     if (dview->merged[DIFF_LEFT])
2999     {
3000         res = mc_util_unlink_backup_if_possible (dview->file[DIFF_LEFT], "~~~");
3001         dview->merged[DIFF_LEFT] = !res;
3002     }
3003     if (dview->merged[DIFF_RIGHT])
3004     {
3005         res = mc_util_unlink_backup_if_possible (dview->file[DIFF_RIGHT], "~~~");
3006         dview->merged[DIFF_RIGHT] = !res;
3007     }
3008     return res;
3009 }
3010
3011 /* --------------------------------------------------------------------------------------------- */
3012
3013 static void
3014 dview_do_save (WDiff * dview)
3015 {
3016     (void) dview_save (dview);
3017 }
3018
3019 /* --------------------------------------------------------------------------------------------- */
3020
3021 static void
3022 dview_save_options (WDiff * dview)
3023 {
3024     mc_config_set_bool (mc_main_config, "DiffView", "show_symbols",
3025                         dview->display_symbols != 0 ? TRUE : FALSE);
3026     mc_config_set_bool (mc_main_config, "DiffView", "show_numbers",
3027                         dview->display_numbers != 0 ? TRUE : FALSE);
3028     mc_config_set_int (mc_main_config, "DiffView", "tab_size", dview->tab_size);
3029
3030     mc_config_set_int (mc_main_config, "DiffView", "diff_quality", dview->opt.quality);
3031
3032     mc_config_set_bool (mc_main_config, "DiffView", "diff_ignore_tws",
3033                         dview->opt.strip_trailing_cr);
3034     mc_config_set_bool (mc_main_config, "DiffView", "diff_ignore_all_space",
3035                         dview->opt.ignore_all_space);
3036     mc_config_set_bool (mc_main_config, "DiffView", "diff_ignore_space_change",
3037                         dview->opt.ignore_space_change);
3038     mc_config_set_bool (mc_main_config, "DiffView", "diff_tab_expansion",
3039                         dview->opt.ignore_tab_expansion);
3040     mc_config_set_bool (mc_main_config, "DiffView", "diff_ignore_case", dview->opt.ignore_case);
3041 }
3042
3043 /* --------------------------------------------------------------------------------------------- */
3044
3045 static void
3046 dview_load_options (WDiff * dview)
3047 {
3048     gboolean show_numbers, show_symbols;
3049     int tab_size;
3050
3051     show_symbols = mc_config_get_bool (mc_main_config, "DiffView", "show_symbols", FALSE);
3052     if (show_symbols)
3053         dview->display_symbols = 1;
3054     show_numbers = mc_config_get_bool (mc_main_config, "DiffView", "show_numbers", FALSE);
3055     if (show_numbers)
3056         dview->display_numbers = calc_nwidth ((const GArray ** const) dview->a);
3057     tab_size = mc_config_get_int (mc_main_config, "DiffView", "tab_size", 8);
3058     if (tab_size > 0 && tab_size < 9)
3059         dview->tab_size = tab_size;
3060     else
3061         dview->tab_size = 8;
3062
3063     dview->opt.quality = mc_config_get_int (mc_main_config, "DiffView", "diff_quality", 0);
3064
3065     dview->opt.strip_trailing_cr =
3066         mc_config_get_bool (mc_main_config, "DiffView", "diff_ignore_tws", FALSE);
3067     dview->opt.ignore_all_space =
3068         mc_config_get_bool (mc_main_config, "DiffView", "diff_ignore_all_space", FALSE);
3069     dview->opt.ignore_space_change =
3070         mc_config_get_bool (mc_main_config, "DiffView", "diff_ignore_space_change", FALSE);
3071     dview->opt.ignore_tab_expansion =
3072         mc_config_get_bool (mc_main_config, "DiffView", "diff_tab_expansion", FALSE);
3073     dview->opt.ignore_case =
3074         mc_config_get_bool (mc_main_config, "DiffView", "diff_ignore_case", FALSE);
3075
3076     dview->new_frame = 1;
3077 }
3078
3079 /* --------------------------------------------------------------------------------------------- */
3080
3081 /*
3082  * Check if it's OK to close the diff viewer.  If there are unsaved changes,
3083  * ask user.
3084  */
3085 static gboolean
3086 dview_ok_to_exit (WDiff * dview)
3087 {
3088     gboolean res = TRUE;
3089     int act;
3090
3091     if (!dview->merged[DIFF_LEFT] && !dview->merged[DIFF_RIGHT])
3092         return res;
3093
3094     act = query_dialog (_("Quit"), !mc_global.midnight_shutdown ?
3095                         _("File(s) was modified. Save with exit?") :
3096                         _("Midnight Commander is being shut down.\nSave modified file(s)?"),
3097                         D_NORMAL, 2, _("&Yes"), _("&No"));
3098
3099     /* Esc is No */
3100     if (mc_global.midnight_shutdown || (act == -1))
3101         act = 1;
3102
3103     switch (act)
3104     {
3105     case -1:                   /* Esc */
3106         res = FALSE;
3107         break;
3108     case 0:                    /* Yes */
3109         (void) dview_save (dview);
3110         res = TRUE;
3111         break;
3112     case 1:                    /* No */
3113         if (mc_util_restore_from_backup_if_possible (dview->file[DIFF_LEFT], "~~~"))
3114             res = mc_util_unlink_backup_if_possible (dview->file[DIFF_LEFT], "~~~");
3115         if (mc_util_restore_from_backup_if_possible (dview->file[DIFF_RIGHT], "~~~"))
3116             res = mc_util_unlink_backup_if_possible (dview->file[DIFF_RIGHT], "~~~");
3117         /* fall through */
3118     default:
3119         res = TRUE;
3120         break;
3121     }
3122     return res;
3123 }
3124
3125 /* --------------------------------------------------------------------------------------------- */
3126
3127 static cb_ret_t
3128 dview_execute_cmd (WDiff * dview, unsigned long command)
3129 {
3130     cb_ret_t res = MSG_HANDLED;
3131
3132     switch (command)
3133     {
3134     case CK_ShowSymbols:
3135         dview->display_symbols ^= 1;
3136         dview->new_frame = 1;
3137         break;
3138     case CK_ShowNumbers:
3139         dview->display_numbers ^= calc_nwidth ((const GArray ** const) dview->a);
3140         dview->new_frame = 1;
3141         break;
3142     case CK_SplitFull:
3143         dview->full ^= 1;
3144         dview->new_frame = 1;
3145         break;
3146     case CK_SplitEqual:
3147         if (!dview->full)
3148         {
3149             dview->bias = 0;
3150             dview->new_frame = 1;
3151         }
3152         break;
3153     case CK_SplitMore:
3154         if (!dview->full)
3155         {
3156             dview_compute_split (dview, 1);
3157             dview->new_frame = 1;
3158         }
3159         break;
3160
3161     case CK_SplitLess:
3162         if (!dview->full)
3163         {
3164             dview_compute_split (dview, -1);
3165             dview->new_frame = 1;
3166         }
3167         break;
3168     case CK_Tab2:
3169         dview->tab_size = 2;
3170         break;
3171     case CK_Tab3:
3172         dview->tab_size = 3;
3173         break;
3174     case CK_Tab4:
3175         dview->tab_size = 4;
3176         break;
3177     case CK_Tab8:
3178         dview->tab_size = 8;
3179         break;
3180     case CK_Swap:
3181         dview->ord ^= 1;
3182         break;
3183     case CK_Redo:
3184         dview_redo (dview);
3185         break;
3186     case CK_HunkNext:
3187         dview->skip_rows = dview->search.last_accessed_num_line =
3188             find_next_hunk (dview->a[DIFF_LEFT], dview->skip_rows);
3189         break;
3190     case CK_HunkPrev:
3191         dview->skip_rows = dview->search.last_accessed_num_line =
3192             find_prev_hunk (dview->a[DIFF_LEFT], dview->skip_rows);
3193         break;
3194     case CK_Goto:
3195         dview_goto_cmd (dview, TRUE);
3196         break;
3197     case CK_Edit:
3198         dview_edit (dview, dview->ord);
3199         break;
3200     case CK_Merge:
3201         do_merge_hunk (dview, FROM_LEFT_TO_RIGHT);
3202         dview_redo (dview);
3203         break;
3204     case CK_MergeOther:
3205         do_merge_hunk (dview, FROM_RIGHT_TO_LEFT);
3206         dview_redo (dview);
3207         break;
3208     case CK_EditOther:
3209         dview_edit (dview, dview->ord ^ 1);
3210         break;
3211     case CK_Search:
3212         dview_search_cmd (dview);
3213         break;
3214     case CK_SearchContinue:
3215         dview_continue_search_cmd (dview);
3216         break;
3217     case CK_Top:
3218         dview->skip_rows = dview->search.last_accessed_num_line = 0;
3219         break;
3220     case CK_Bottom:
3221         dview->skip_rows = dview->search.last_accessed_num_line = dview->a[DIFF_LEFT]->len - 1;
3222         break;
3223     case CK_Up:
3224         if (dview->skip_rows > 0)
3225         {
3226             dview->skip_rows--;
3227             dview->search.last_accessed_num_line = dview->skip_rows;
3228         }
3229         break;
3230     case CK_Down:
3231         dview->skip_rows++;
3232         dview->search.last_accessed_num_line = dview->skip_rows;
3233         break;
3234     case CK_PageDown:
3235         if (dview->height > 2)
3236         {
3237             dview->skip_rows += dview->height - 2;
3238             dview->search.last_accessed_num_line = dview->skip_rows;
3239         }
3240         break;
3241     case CK_PageUp:
3242         if (dview->height > 2)
3243         {
3244             dview->skip_rows -= dview->height - 2;
3245             dview->search.last_accessed_num_line = dview->skip_rows;
3246         }
3247         break;
3248     case CK_Left:
3249         dview->skip_cols--;
3250         break;
3251     case CK_Right:
3252         dview->skip_cols++;
3253         break;
3254     case CK_LeftQuick:
3255         dview->skip_cols -= 8;
3256         break;
3257     case CK_RightQuick:
3258         dview->skip_cols += 8;
3259         break;
3260     case CK_Home:
3261         dview->skip_cols = 0;
3262         break;
3263     case CK_Shell:
3264         view_other_cmd ();
3265         break;
3266     case CK_Quit:
3267         dview->view_quit = 1;
3268         break;
3269     case CK_Save:
3270         dview_do_save (dview);
3271         break;
3272     case CK_Options:
3273         dview_diff_options (dview);
3274         break;
3275 #ifdef HAVE_CHARSET
3276     case CK_SelectCodepage:
3277         dview_select_encoding (dview);
3278         break;
3279 #endif
3280     case CK_Cancel:
3281         /* don't close diffviewer due to SIGINT */
3282         break;
3283     default:
3284         res = MSG_NOT_HANDLED;
3285     }
3286     return res;
3287 }
3288
3289 /* --------------------------------------------------------------------------------------------- */
3290
3291 static cb_ret_t
3292 dview_handle_key (WDiff * dview, int key)
3293 {
3294     unsigned long command;
3295
3296 #ifdef HAVE_CHARSET
3297     key = convert_from_input_c (key);
3298 #endif
3299
3300     command = keybind_lookup_keymap_command (diff_map, key);
3301     if ((command != CK_IgnoreKey) && (dview_execute_cmd (dview, command) == MSG_HANDLED))
3302         return MSG_HANDLED;
3303
3304     /* Key not used */
3305     return MSG_NOT_HANDLED;
3306 }
3307
3308 /* --------------------------------------------------------------------------------------------- */
3309
3310 static cb_ret_t
3311 dview_callback (Widget * w, Widget * sender, widget_msg_t msg, int parm, void *data)
3312 {
3313     WDiff *dview = (WDiff *) w;
3314     WDialog *h = w->owner;
3315     cb_ret_t i;
3316
3317     switch (msg)
3318     {
3319     case MSG_INIT:
3320         dview_labels (dview);
3321         dview_load_options (dview);
3322         dview_update (dview);
3323         return MSG_HANDLED;
3324
3325     case MSG_DRAW:
3326         dview->new_frame = 1;
3327         dview_update (dview);
3328         return MSG_HANDLED;
3329
3330     case MSG_KEY:
3331         i = dview_handle_key (dview, parm);
3332         if (dview->view_quit)
3333             dlg_stop (h);
3334         else
3335             dview_update (dview);
3336         return i;
3337
3338     case MSG_ACTION:
3339         i = dview_execute_cmd (dview, parm);
3340         if (dview->view_quit)
3341             dlg_stop (h);
3342         else
3343             dview_update (dview);
3344         return i;
3345
3346     case MSG_DESTROY:
3347         dview_save_options (dview);
3348         dview_fini (dview);
3349         return MSG_HANDLED;
3350
3351     default:
3352         return widget_default_callback (w, sender, msg, parm, data);
3353     }
3354 }
3355
3356 /* --------------------------------------------------------------------------------------------- */
3357
3358 static void
3359 dview_adjust_size (WDialog * h)
3360 {
3361     WDiff *dview;
3362     WButtonBar *bar;
3363
3364     /* Look up the viewer and the buttonbar, we assume only two widgets here */
3365     dview = (WDiff *) find_widget_type (h, dview_callback);
3366     bar = find_buttonbar (h);
3367     widget_set_size (WIDGET (dview), 0, 0, LINES - 1, COLS);
3368     widget_set_size (WIDGET (bar), LINES - 1, 0, 1, COLS);
3369
3370     dview_compute_areas (dview);
3371 }
3372
3373 /* --------------------------------------------------------------------------------------------- */
3374
3375 static cb_ret_t
3376 dview_dialog_callback (Widget * w, Widget * sender, widget_msg_t msg, int parm, void *data)
3377 {
3378     WDiff *dview = (WDiff *) data;
3379     WDialog *h = DIALOG (w);
3380
3381     switch (msg)
3382     {
3383     case MSG_RESIZE:
3384         dview_adjust_size (h);
3385         return MSG_HANDLED;
3386
3387     case MSG_ACTION:
3388         /* shortcut */
3389         if (sender == NULL)
3390             return dview_execute_cmd (NULL, parm);
3391         /* message from buttonbar */
3392         if (sender == WIDGET (find_buttonbar (h)))
3393         {
3394             if (data != NULL)
3395                 return send_message (data, NULL, MSG_ACTION, parm, NULL);
3396
3397             dview = (WDiff *) find_widget_type (h, dview_callback);
3398             return dview_execute_cmd (dview, parm);
3399         }
3400         return MSG_NOT_HANDLED;
3401
3402     case MSG_VALIDATE:
3403         dview = (WDiff *) find_widget_type (h, dview_callback);
3404         h->state = DLG_ACTIVE;  /* don't stop the dialog before final decision */
3405         if (dview_ok_to_exit (dview))
3406             h->state = DLG_CLOSED;
3407         return MSG_HANDLED;
3408
3409     default:
3410         return dlg_default_callback (w, sender, msg, parm, data);
3411     }
3412 }
3413
3414 /* --------------------------------------------------------------------------------------------- */
3415
3416 static char *
3417 dview_get_title (const WDialog * h, size_t len)
3418 {
3419     const WDiff *dview;
3420     const char *modified = " (*) ";
3421     const char *notmodified = "     ";
3422     size_t len1;
3423     GString *title;
3424
3425     dview = (const WDiff *) find_widget_type (h, dview_callback);
3426     len1 = (len - str_term_width1 (_("Diff:")) - strlen (modified) - 3) / 2;
3427
3428     title = g_string_sized_new (len);
3429     g_string_append (title, _("Diff:"));
3430     g_string_append (title, dview->merged[DIFF_LEFT] ? modified : notmodified);
3431     g_string_append (title, str_term_trim (dview->label[DIFF_LEFT], len1));
3432     g_string_append (title, " | ");
3433     g_string_append (title, dview->merged[DIFF_RIGHT] ? modified : notmodified);
3434     g_string_append (title, str_term_trim (dview->label[DIFF_RIGHT], len1));
3435
3436     return g_string_free (title, FALSE);
3437 }
3438
3439 /* --------------------------------------------------------------------------------------------- */
3440
3441 static int
3442 diff_view (const char *file1, const char *file2, const char *label1, const char *label2)
3443 {
3444     int error;
3445     WDiff *dview;
3446     Widget *w;
3447     WDialog *dview_dlg;
3448
3449     /* Create dialog and widgets, put them on the dialog */
3450     dview_dlg =
3451         create_dlg (FALSE, 0, 0, LINES, COLS, NULL, dview_dialog_callback, NULL,
3452                     "[Diff Viewer]", NULL, DLG_WANT_TAB);
3453
3454     dview = g_new0 (WDiff, 1);
3455     w = WIDGET (dview);
3456     init_widget (w, 0, 0, LINES - 1, COLS, dview_callback, dview_event);
3457     widget_want_cursor (w, FALSE);
3458
3459     add_widget (dview_dlg, dview);
3460     add_widget (dview_dlg, buttonbar_new (TRUE));
3461
3462     dview_dlg->get_title = dview_get_title;
3463
3464     error = dview_init (dview, "-a", file1, file2, label1, label2, DATA_SRC_MEM);       /* XXX binary diff? */
3465
3466     /* Please note that if you add another widget,
3467      * you have to modify dview_adjust_size to
3468      * be aware of it
3469      */
3470     if (error == 0)
3471         run_dlg (dview_dlg);
3472
3473     if ((error != 0) || (dview_dlg->state == DLG_CLOSED))
3474         destroy_dlg (dview_dlg);
3475
3476     return error == 0 ? 1 : 0;
3477 }
3478
3479 /*** public functions ****************************************************************************/
3480 /* --------------------------------------------------------------------------------------------- */
3481
3482 #define GET_FILE_AND_STAMP(n) \
3483 do \
3484 { \
3485     use_copy##n = 0; \
3486     real_file##n = file##n; \
3487     if (!vfs_file_is_local (file##n)) \
3488     { \
3489         real_file##n = mc_getlocalcopy (file##n); \
3490         if (real_file##n != NULL) \
3491         { \
3492             use_copy##n = 1; \
3493             if (mc_stat (real_file##n, &st##n) != 0) \
3494                 use_copy##n = -1; \
3495         } \
3496     } \
3497 } \
3498 while (0)
3499
3500 #define UNGET_FILE(n) \
3501 do \
3502 { \
3503     if (use_copy##n) \
3504     { \
3505         int changed = 0; \
3506         if (use_copy##n > 0) \
3507         { \
3508             time_t mtime; \
3509             mtime = st##n.st_mtime; \
3510             if (mc_stat (real_file##n, &st##n) == 0) \
3511                 changed = (mtime != st##n.st_mtime); \
3512         } \
3513         mc_ungetlocalcopy (file##n, real_file##n, changed); \
3514         vfs_path_free (real_file##n); \
3515     } \
3516 } \
3517 while (0)
3518
3519 gboolean
3520 dview_diff_cmd (const void *f0, const void *f1)
3521 {
3522     int rv = 0;
3523     vfs_path_t *file0 = NULL;
3524     vfs_path_t *file1 = NULL;
3525     gboolean is_dir0 = FALSE;
3526     gboolean is_dir1 = FALSE;
3527
3528     switch (mc_global.mc_run_mode)
3529     {
3530     case MC_RUN_FULL:
3531         {
3532             /* run from panels */
3533             const WPanel *panel0 = (const WPanel *) f0;
3534             const WPanel *panel1 = (const WPanel *) f1;
3535
3536             file0 = vfs_path_append_new (panel0->cwd_vpath, selection (panel0)->fname, NULL);
3537             is_dir0 = S_ISDIR (selection (panel0)->st.st_mode);
3538             if (is_dir0)
3539             {
3540                 message (D_ERROR, MSG_ERROR, _("\"%s\" is a directory"),
3541                          path_trunc (selection (panel0)->fname, 30));
3542                 goto ret;
3543             }
3544
3545             file1 = vfs_path_append_new (panel1->cwd_vpath, selection (panel1)->fname, NULL);
3546             is_dir1 = S_ISDIR (selection (panel1)->st.st_mode);
3547             if (is_dir1)
3548             {
3549                 message (D_ERROR, MSG_ERROR, _("\"%s\" is a directory"),
3550                          path_trunc (selection (panel1)->fname, 30));
3551                 goto ret;
3552             }
3553             break;
3554         }
3555
3556     case MC_RUN_DIFFVIEWER:
3557         {
3558             /* run from command line */
3559             const char *p0 = (const char *) f0;
3560             const char *p1 = (const char *) f1;
3561             struct stat st;
3562
3563             file0 = vfs_path_from_str (p0);
3564             if (mc_stat (file0, &st) == 0)
3565             {
3566                 is_dir0 = S_ISDIR (st.st_mode);
3567                 if (is_dir0)
3568                 {
3569                     message (D_ERROR, MSG_ERROR, _("\"%s\" is a directory"), path_trunc (p0, 30));
3570                     goto ret;
3571                 }
3572             }
3573             else
3574             {
3575                 message (D_ERROR, MSG_ERROR, _("Cannot stat \"%s\"\n%s"),
3576                          path_trunc (p0, 30), unix_error_string (errno));
3577                 goto ret;
3578             }
3579
3580             file1 = vfs_path_from_str (p1);
3581             if (mc_stat (file1, &st) == 0)
3582             {
3583                 is_dir1 = S_ISDIR (st.st_mode);
3584                 if (is_dir1)
3585                 {
3586                     message (D_ERROR, MSG_ERROR, _("\"%s\" is a directory"), path_trunc (p1, 30));
3587                     goto ret;
3588                 }
3589             }
3590             else
3591             {
3592                 message (D_ERROR, MSG_ERROR, _("Cannot stat \"%s\"\n%s"),
3593                          path_trunc (p1, 30), unix_error_string (errno));
3594                 goto ret;
3595             }
3596             break;
3597         }
3598
3599     default:
3600         /* this should not happaned */
3601         message (D_ERROR, MSG_ERROR, _("Diff viewer: invalid mode"));
3602         return FALSE;
3603     }
3604
3605     if (rv == 0)
3606     {
3607         rv = -1;
3608         if (file0 != NULL && file1 != NULL)
3609         {
3610             int use_copy0;
3611             int use_copy1;
3612             struct stat st0;
3613             struct stat st1;
3614             vfs_path_t *real_file0;
3615             vfs_path_t *real_file1;
3616
3617             GET_FILE_AND_STAMP (0);
3618             GET_FILE_AND_STAMP (1);
3619             if (real_file0 != NULL && real_file1 != NULL)
3620             {
3621                 char *real_file0_str, *real_file1_str;
3622                 char *file0_str, *file1_str;
3623
3624                 real_file0_str = vfs_path_to_str (real_file0);
3625                 real_file1_str = vfs_path_to_str (real_file1);
3626                 file0_str = vfs_path_to_str (file0);
3627                 file1_str = vfs_path_to_str (file1);
3628                 rv = diff_view (real_file0_str, real_file1_str, file0_str, file1_str);
3629                 g_free (real_file0_str);
3630                 g_free (real_file1_str);
3631                 g_free (file0_str);
3632                 g_free (file1_str);
3633             }
3634             UNGET_FILE (1);
3635             UNGET_FILE (0);
3636         }
3637     }
3638
3639     if (rv == 0)
3640         message (D_ERROR, MSG_ERROR, _("Two files are needed to compare"));
3641
3642   ret:
3643     vfs_path_free (file1);
3644     vfs_path_free (file0);
3645
3646     return (rv != 0);
3647 }
3648
3649 #undef GET_FILE_AND_STAMP
3650 #undef UNGET_FILE
3651
3652 /* --------------------------------------------------------------------------------------------- */