src/diffviewer/ydiff.c

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