lib/util.c

   1 /* Various utilities
   2    Copyright (C) 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003,
   3    2004, 2005, 2007, 2009 Free Software Foundation, Inc.
   4    Written 1994, 1995, 1996 by:
   5    Miguel de Icaza, Janne Kukonlehto, Dugan Porter,
   6    Jakub Jelinek, Mauricio Plaza.
   7
   8    The file_date routine is mostly from GNU's fileutils package,
   9    written by Richard Stallman and David MacKenzie.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 2 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program; if not, write to the Free Software
  23    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  24
  25 /** \file
  26  *  \brief Source: various utilities
  27  */
  28
  29 #include <config.h>
  30
  31 #include <ctype.h>
  32 #include <limits.h>
  33 #include <stdarg.h>
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <fcntl.h>
  38 #include <sys/time.h>
  39 #include <sys/types.h>
  40 #include <sys/stat.h>
  41 #include <unistd.h>
  42
  43 #include "lib/global.h"
  44 #include "lib/tty/win.h"        /* xterm_flag */
  45 #include "lib/mcconfig.h"
  46 #include "lib/fileloc.h"
  47 #include "lib/vfs/vfs.h"
  48 #include "lib/strutil.h"
  49 #include "lib/util.h"
  50
  51 /*** global variables ****************************************************************************/
  52
  53 /*** file scope macro definitions ****************************************************************/
  54
  55 #define ismode(n,m) ((n & m) == m)
  56
  57 /* Number of attempts to create a temporary file */
  58 #ifndef TMP_MAX
  59 #define TMP_MAX 16384
  60 #endif /* !TMP_MAX */
  61
  62 #define TMP_SUFFIX ".tmp"
  63
  64 #define ASCII_A (0x40 + 1)
  65 #define ASCII_Z (0x40 + 26)
  66 #define ASCII_a (0x60 + 1)
  67 #define ASCII_z (0x60 + 26)
  68
  69 /*** file scope type declarations ****************************************************************/
  70
  71 /*** file scope variables ************************************************************************/
  72
  73 /*** file scope functions ************************************************************************/
  74 /* --------------------------------------------------------------------------------------------- */
  75
  76 static inline int
  77 is_7bit_printable (unsigned char c)
  78 {
  79     return (c > 31 && c < 127);
  80 }
  81
  82 /* --------------------------------------------------------------------------------------------- */
  83
  84 static inline int
  85 is_iso_printable (unsigned char c)
  86 {
  87     return ((c > 31 && c < 127) || c >= 160);
  88 }
  89
  90 /* --------------------------------------------------------------------------------------------- */
  91
  92 static inline int
  93 is_8bit_printable (unsigned char c)
  94 {
  95     /* "Full 8 bits output" doesn't work on xterm */
  96     if (xterm_flag)
  97         return is_iso_printable (c);
  98
  99     return (c > 31 && c != 127 && c != 155);
 100 }
 101
 102 /* --------------------------------------------------------------------------------------------- */
 103
 104 static char *
 105 resolve_symlinks (const char *path)
 106 {
 107     char *buf, *buf2, *q, *r, c;
 108     int len;
 109     struct stat mybuf;
 110     const char *p;
 111
 112     if (*path != PATH_SEP)
 113         return NULL;
 114     r = buf = g_malloc (MC_MAXPATHLEN);
 115     buf2 = g_malloc (MC_MAXPATHLEN);
 116     *r++ = PATH_SEP;
 117     *r = 0;
 118     p = path;
 119     for (;;)
 120     {
 121         q = strchr (p + 1, PATH_SEP);
 122         if (!q)
 123         {
 124             q = strchr (p + 1, 0);
 125             if (q == p + 1)
 126                 break;
 127         }
 128         c = *q;
 129         *q = 0;
 130         if (mc_lstat (path, &mybuf) < 0)
 131         {
 132             g_free (buf);
 133             g_free (buf2);
 134             *q = c;
 135             return NULL;
 136         }
 137         if (!S_ISLNK (mybuf.st_mode))
 138             strcpy (r, p + 1);
 139         else
 140         {
 141             len = mc_readlink (path, buf2, MC_MAXPATHLEN - 1);
 142             if (len < 0)
 143             {
 144                 g_free (buf);
 145                 g_free (buf2);
 146                 *q = c;
 147                 return NULL;
 148             }
 149             buf2[len] = 0;
 150             if (*buf2 == PATH_SEP)
 151                 strcpy (buf, buf2);
 152             else
 153                 strcpy (r, buf2);
 154         }
 155         canonicalize_pathname (buf);
 156         r = strchr (buf, 0);
 157         if (!*r || *(r - 1) != PATH_SEP)
 158         {
 159             *r++ = PATH_SEP;
 160             *r = 0;
 161         }
 162         *q = c;
 163         p = q;
 164         if (!c)
 165             break;
 166     }
 167     if (!*buf)
 168         strcpy (buf, PATH_SEP_STR);
 169     else if (*(r - 1) == PATH_SEP && r != buf + 1)
 170         *(r - 1) = 0;
 171     g_free (buf2);
 172     return buf;
 173 }
 174
 175 /* --------------------------------------------------------------------------------------------- */
 176
 177 static gboolean
 178 mc_util_write_backup_content (const char *from_file_name, const char *to_file_name)
 179 {
 180     FILE *backup_fd;
 181     char *contents;
 182     gsize length;
 183     gboolean ret1 = TRUE;
 184
 185     if (!g_file_get_contents (from_file_name, &contents, &length, NULL))
 186         return FALSE;
 187
 188     backup_fd = fopen (to_file_name, "w");
 189     if (backup_fd == NULL)
 190     {
 191         g_free (contents);
 192         return FALSE;
 193     }
 194
 195     if (fwrite ((const void *) contents, 1, length, backup_fd) != length)
 196         ret1 = FALSE;
 197     {
 198         int ret2;
 199         ret2 = fflush (backup_fd);
 200         ret2 = fclose (backup_fd);
 201     }
 202     g_free (contents);
 203     return ret1;
 204 }
 205
 206 /* --------------------------------------------------------------------------------------------- */
 207 /*** public functions ****************************************************************************/
 208 /* --------------------------------------------------------------------------------------------- */
 209
 210 int
 211 is_printable (int c)
 212 {
 213     c &= 0xff;
 214
 215 #ifdef HAVE_CHARSET
 216     /* "Display bits" is ignored, since the user controls the output
 217        by setting the output codepage */
 218     return is_8bit_printable (c);
 219 #else
 220     if (!mc_global.eight_bit_clean)
 221         return is_7bit_printable (c);
 222
 223     if (mc_global.full_eight_bits)
 224     {
 225         return is_8bit_printable (c);
 226     }
 227     else
 228         return is_iso_printable (c);
 229 #endif /* !HAVE_CHARSET */
 230 }
 231
 232 /* --------------------------------------------------------------------------------------------- */
 233 /**
 234  * Quote the filename for the purpose of inserting it into the command
 235  * line.  If quote_percent is 1, replace "%" with "%%" - the percent is
 236  * processed by the mc command line.
 237  */
 238 char *
 239 name_quote (const char *s, int quote_percent)
 240 {
 241     char *ret, *d;
 242
 243     d = ret = g_malloc (strlen (s) * 2 + 2 + 1);
 244     if (*s == '-')
 245     {
 246         *d++ = '.';
 247         *d++ = '/';
 248     }
 249
 250     for (; *s; s++, d++)
 251     {
 252         switch (*s)
 253         {
 254         case '%':
 255             if (quote_percent)
 256                 *d++ = '%';
 257             break;
 258         case '\'':
 259         case '\\':
 260         case '\r':
 261         case '\n':
 262         case '\t':
 263         case '"':
 264         case ';':
 265         case ' ':
 266         case '?':
 267         case '|':
 268         case '[':
 269         case ']':
 270         case '{':
 271         case '}':
 272         case '<':
 273         case '>':
 274         case '`':
 275         case '!':
 276         case '$':
 277         case '&':
 278         case '*':
 279         case '(':
 280         case ')':
 281             *d++ = '\\';
 282             break;
 283         case '~':
 284         case '#':
 285             if (d == ret)
 286                 *d++ = '\\';
 287             break;
 288         }
 289         *d = *s;
 290     }
 291     *d = '\0';
 292     return ret;
 293 }
 294
 295 /* --------------------------------------------------------------------------------------------- */
 296
 297 char *
 298 fake_name_quote (const char *s, int quote_percent)
 299 {
 300     (void) quote_percent;
 301     return g_strdup (s);
 302 }
 303
 304 /* --------------------------------------------------------------------------------------------- */
 305 /**
 306  * path_trunc() is the same as str_trunc() but
 307  * it deletes possible password from path for security
 308  * reasons.
 309  */
 310
 311 const char *
 312 path_trunc (const char *path, size_t trunc_len)
 313 {
 314     char *secure_path = strip_password (g_strdup (path), 1);
 315
 316     const char *ret = str_trunc (secure_path, trunc_len);
 317     g_free (secure_path);
 318
 319     return ret;
 320 }
 321
 322 /* --------------------------------------------------------------------------------------------- */
 323
 324 const char *
 325 size_trunc (uintmax_t size, gboolean use_si)
 326 {
 327     static char x[BUF_TINY];
 328     uintmax_t divisor = 1;
 329     const char *xtra = "";
 330
 331     if (size > 999999999UL)
 332     {
 333         divisor = use_si ? 1000 : 1024;
 334         xtra = use_si ? "k" : "K";
 335         if (size / divisor > 999999999UL)
 336         {
 337             divisor = use_si ? (1000 * 1000) : (1024 * 1024);
 338             xtra = use_si ? "m" : "M";
 339         }
 340     }
 341     g_snprintf (x, sizeof (x), "%.0f%s", 1.0 * size / divisor, xtra);
 342     return x;
 343 }
 344
 345 /* --------------------------------------------------------------------------------------------- */
 346
 347 const char *
 348 size_trunc_sep (uintmax_t size, gboolean use_si)
 349 {
 350     static char x[60];
 351     int count;
 352     const char *p, *y;
 353     char *d;
 354
 355     p = y = size_trunc (size, use_si);
 356     p += strlen (p) - 1;
 357     d = x + sizeof (x) - 1;
 358     *d-- = '\0';
 359     while (p >= y && isalpha ((unsigned char) *p))
 360         *d-- = *p--;
 361     for (count = 0; p >= y; count++)
 362     {
 363         if (count == 3)
 364         {
 365             *d-- = ',';
 366             count = 0;
 367         }
 368         *d-- = *p--;
 369     }
 370     d++;
 371     if (*d == ',')
 372         d++;
 373     return d;
 374 }
 375
 376 /* --------------------------------------------------------------------------------------------- */
 377 /**
 378  * Print file SIZE to BUFFER, but don't exceed LEN characters,
 379  * not including trailing 0. BUFFER should be at least LEN+1 long.
 380  * This function is called for every file on panels, so avoid
 381  * floating point by any means.
 382  *
 383  * Units: size units (filesystem sizes are 1K blocks)
 384  *    0=bytes, 1=Kbytes, 2=Mbytes, etc.
 385  */
 386
 387 void
 388 size_trunc_len (char *buffer, unsigned int len, uintmax_t size, int units, gboolean use_si)
 389 {
 390     /* Avoid taking power for every file.  */
 391     static const uintmax_t power10[] = {
 392         1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000
 393     };
 394     static const char *const suffix[] = { "", "K", "M", "G", "T", "P", "E", "Z", "Y", NULL };
 395     static const char *const suffix_lc[] = { "", "k", "m", "g", "t", "p", "e", "z", "y", NULL };
 396     int j = 0;
 397     int size_remain;
 398
 399     if (len == 0)
 400         len = 9;
 401
 402     /*
 403      * recalculate from 1024 base to 1000 base if units>0
 404      * We can't just multiply by 1024 - that might cause overflow
 405      * if off_t type is too small
 406      */
 407     if (use_si)
 408         for (j = 0; j < units; j++)
 409         {
 410             size_remain = ((size % 125) * 1024) / 1000; /* size mod 125, recalculated */
 411             size = size / 125;  /* 128/125 = 1024/1000 */
 412             size = size * 128;  /* This will convert size from multiple of 1024 to multiple of 1000 */
 413             size += size_remain;        /* Re-add remainder lost by division/multiplication */
 414         }
 415
 416     for (j = units; suffix[j] != NULL; j++)
 417     {
 418         if (size == 0)
 419         {
 420             if (j == units)
 421             {
 422                 /* Empty files will print "0" even with minimal width.  */
 423                 g_snprintf (buffer, len + 1, "0");
 424                 break;
 425             }
 426
 427             /* Use "~K" or just "K" if len is 1.  Use "B" for bytes.  */
 428             g_snprintf (buffer, len + 1, (len > 1) ? "~%s" : "%s",
 429                         (j > 1) ? (use_si ? suffix_lc[j - 1] : suffix[j - 1]) : "B");
 430             break;
 431         }
 432
 433         if (size < power10[len - (j > 0)])
 434         {
 435             g_snprintf (buffer, len + 1, "%" PRIuMAX "%s", size, use_si ? suffix_lc[j] : suffix[j]);
 436             break;
 437         }
 438
 439         /* Powers of 1000 or 1024, with rounding.  */
 440         if (use_si)
 441             size = (size + 500) / 1000;
 442         else
 443             size = (size + 512) >> 10;
 444     }
 445 }
 446
 447 /* --------------------------------------------------------------------------------------------- */
 448
 449 const char *
 450 string_perm (mode_t mode_bits)
 451 {
 452     static char mode[11];
 453
 454     strcpy (mode, "----------");
 455     if (S_ISDIR (mode_bits))
 456         mode[0] = 'd';
 457     if (S_ISCHR (mode_bits))
 458         mode[0] = 'c';
 459     if (S_ISBLK (mode_bits))
 460         mode[0] = 'b';
 461     if (S_ISLNK (mode_bits))
 462         mode[0] = 'l';
 463     if (S_ISFIFO (mode_bits))
 464         mode[0] = 'p';
 465     if (S_ISNAM (mode_bits))
 466         mode[0] = 'n';
 467     if (S_ISSOCK (mode_bits))
 468         mode[0] = 's';
 469     if (S_ISDOOR (mode_bits))
 470         mode[0] = 'D';
 471     if (ismode (mode_bits, S_IXOTH))
 472         mode[9] = 'x';
 473     if (ismode (mode_bits, S_IWOTH))
 474         mode[8] = 'w';
 475     if (ismode (mode_bits, S_IROTH))
 476         mode[7] = 'r';
 477     if (ismode (mode_bits, S_IXGRP))
 478         mode[6] = 'x';
 479     if (ismode (mode_bits, S_IWGRP))
 480         mode[5] = 'w';
 481     if (ismode (mode_bits, S_IRGRP))
 482         mode[4] = 'r';
 483     if (ismode (mode_bits, S_IXUSR))
 484         mode[3] = 'x';
 485     if (ismode (mode_bits, S_IWUSR))
 486         mode[2] = 'w';
 487     if (ismode (mode_bits, S_IRUSR))
 488         mode[1] = 'r';
 489 #ifdef S_ISUID
 490     if (ismode (mode_bits, S_ISUID))
 491         mode[3] = (mode[3] == 'x') ? 's' : 'S';
 492 #endif /* S_ISUID */
 493 #ifdef S_ISGID
 494     if (ismode (mode_bits, S_ISGID))
 495         mode[6] = (mode[6] == 'x') ? 's' : 'S';
 496 #endif /* S_ISGID */
 497 #ifdef S_ISVTX
 498     if (ismode (mode_bits, S_ISVTX))
 499         mode[9] = (mode[9] == 'x') ? 't' : 'T';
 500 #endif /* S_ISVTX */
 501     return mode;
 502 }
 503
 504 /* --------------------------------------------------------------------------------------------- */
 505 /**
 506  *  p: string which might contain an url with a password (this parameter is
 507  *  modified in place).
 508  *  has_prefix = 0: The first parameter is an url without a prefix
 509  *  (user[:pass]@]machine[:port][remote-dir). Delete
 510  *  the password.
 511  *  has_prefix = 1: Search p for known url prefixes. If found delete
 512  *  the password from the url.
 513  *  Caveat: only the first url is found
 514  */
 515
 516 char *
 517 strip_password (char *p, int has_prefix)
 518 {
 519     static const struct
 520     {
 521         const char *name;
 522         size_t len;
 523     } prefixes[] =
 524     {
 525         /* *INDENT-OFF* */
 526         { "/#ftp:", 6 },
 527         { "ftp://", 6 },
 528         { "/#smb:", 6 },
 529         { "smb://", 6 },
 530         { "/#sh:", 5 },
 531         { "sh://", 5 },
 532         { "ssh://", 6 }
 533         /* *INDENT-ON* */
 534     };
 535
 536     char *at, *inner_colon, *dir;
 537     size_t i;
 538     char *result = p;
 539
 540     for (i = 0; i < sizeof (prefixes) / sizeof (prefixes[0]); i++)
 541     {
 542         char *q;
 543
 544         if (has_prefix)
 545         {
 546             q = strstr (p, prefixes[i].name);
 547             if (q == NULL)
 548                 continue;
 549             else
 550                 p = q + prefixes[i].len;
 551         }
 552
 553         dir = strchr (p, PATH_SEP);
 554         if (dir != NULL)
 555             *dir = '\0';
 556
 557         /* search for any possible user */
 558         at = strrchr (p, '@');
 559
 560         if (dir)
 561             *dir = PATH_SEP;
 562
 563         /* We have a username */
 564         if (at)
 565         {
 566             inner_colon = memchr (p, ':', at - p);
 567             if (inner_colon)
 568                 memmove (inner_colon, at, strlen (at) + 1);
 569         }
 570         break;
 571     }
 572     return (result);
 573 }
 574
 575 /* --------------------------------------------------------------------------------------------- */
 576
 577 const char *
 578 strip_home_and_password (const char *dir)
 579 {
 580     size_t len;
 581     static char newdir[MC_MAXPATHLEN];
 582
 583     len = strlen (mc_config_get_home_dir ());
 584     if (mc_config_get_home_dir () != NULL && strncmp (dir, mc_config_get_home_dir (), len) == 0 &&
 585         (dir[len] == PATH_SEP || dir[len] == '\0'))
 586     {
 587         newdir[0] = '~';
 588         g_strlcpy (&newdir[1], &dir[len], sizeof (newdir) - 1);
 589         return newdir;
 590     }
 591
 592     /* We do not strip homes in /#ftp tree, I do not like ~'s there
 593        (see ftpfs.c why) */
 594     g_strlcpy (newdir, dir, sizeof (newdir));
 595     strip_password (newdir, 1);
 596     return newdir;
 597 }
 598
 599 /* --------------------------------------------------------------------------------------------- */
 600
 601 const char *
 602 extension (const char *filename)
 603 {
 604     const char *d = strrchr (filename, '.');
 605     return (d != NULL) ? d + 1 : "";
 606 }
 607
 608 /* --------------------------------------------------------------------------------------------- */
 609
 610 char *
 611 load_mc_home_file (const char *from, const char *filename, char **allocated_filename)
 612 {
 613     char *hintfile_base, *hintfile;
 614     char *lang;
 615     char *data;
 616
 617     hintfile_base = g_build_filename (from, filename, (char *) NULL);
 618     lang = guess_message_value ();
 619
 620     hintfile = g_strconcat (hintfile_base, ".", lang, (char *) NULL);
 621     if (!g_file_get_contents (hintfile, &data, NULL, NULL))
 622     {
 623         /* Fall back to the two-letter language code */
 624         if (lang[0] != '\0' && lang[1] != '\0')
 625             lang[2] = '\0';
 626         g_free (hintfile);
 627         hintfile = g_strconcat (hintfile_base, ".", lang, (char *) NULL);
 628         if (!g_file_get_contents (hintfile, &data, NULL, NULL))
 629         {
 630             g_free (hintfile);
 631             hintfile = hintfile_base;
 632             g_file_get_contents (hintfile_base, &data, NULL, NULL);
 633         }
 634     }
 635
 636     g_free (lang);
 637
 638     if (hintfile != hintfile_base)
 639         g_free (hintfile_base);
 640
 641     if (allocated_filename != NULL)
 642         *allocated_filename = hintfile;
 643     else
 644         g_free (hintfile);
 645
 646     return data;
 647 }
 648
 649 /* --------------------------------------------------------------------------------------------- */
 650
 651 const char *
 652 extract_line (const char *s, const char *top)
 653 {
 654     static char tmp_line[BUF_MEDIUM];
 655     char *t = tmp_line;
 656
 657     while (*s && *s != '\n' && (size_t) (t - tmp_line) < sizeof (tmp_line) - 1 && s < top)
 658         *t++ = *s++;
 659     *t = 0;
 660     return tmp_line;
 661 }
 662
 663 /* --------------------------------------------------------------------------------------------- */
 664 /**
 665  * The basename routine
 666  */
 667
 668 const char *
 669 x_basename (const char *s)
 670 {
 671     const char *where;
 672
 673     where = g_strrstr (s, VFS_PATH_URL_DELIMITER);
 674     if (where == NULL)
 675         return ((where = strrchr (s, PATH_SEP))) ? where + 1 : s;
 676
 677     while (--where > s && *where != PATH_SEP);
 678     while (--where > s && *where != PATH_SEP);
 679
 680     return (where == s ) ? s: where + 1;
 681 }
 682
 683 /* --------------------------------------------------------------------------------------------- */
 684
 685 const char *
 686 unix_error_string (int error_num)
 687 {
 688     static char buffer[BUF_LARGE];
 689     gchar *strerror_currentlocale;
 690
 691     strerror_currentlocale = g_locale_from_utf8 (g_strerror (error_num), -1, NULL, NULL, NULL);
 692     g_snprintf (buffer, sizeof (buffer), "%s (%d)", strerror_currentlocale, error_num);
 693     g_free (strerror_currentlocale);
 694
 695     return buffer;
 696 }
 697
 698 /* --------------------------------------------------------------------------------------------- */
 699
 700 const char *
 701 skip_separators (const char *s)
 702 {
 703     const char *su = s;
 704
 705     for (; *su; str_cnext_char (&su))
 706         if (*su != ' ' && *su != '\t' && *su != ',')
 707             break;
 708
 709     return su;
 710 }
 711
 712 /* --------------------------------------------------------------------------------------------- */
 713
 714 const char *
 715 skip_numbers (const char *s)
 716 {
 717     const char *su = s;
 718
 719     for (; *su; str_cnext_char (&su))
 720         if (!str_isdigit (su))
 721             break;
 722
 723     return su;
 724 }
 725
 726 /* --------------------------------------------------------------------------------------------- */
 727 /**
 728  * Remove all control sequences from the argument string.  We define
 729  * "control sequence", in a sort of pidgin BNF, as follows:
 730  *
 731  * control-seq = Esc non-'['
 732  *             | Esc '[' (0 or more digits or ';' or '?') (any other char)
 733  *
 734  * This scheme works for all the terminals described in my termcap /
 735  * terminfo databases, except the Hewlett-Packard 70092 and some Wyse
 736  * terminals.  If I hear from a single person who uses such a terminal
 737  * with MC, I'll be glad to add support for it.  (Dugan)
 738  * Non-printable characters are also removed.
 739  */
 740
 741 char *
 742 strip_ctrl_codes (char *s)
 743 {
 744     char *w;                    /* Current position where the stripped data is written */
 745     char *r;                    /* Current position where the original data is read */
 746     char *n;
 747
 748     if (!s)
 749         return 0;
 750
 751     for (w = s, r = s; *r;)
 752     {
 753         if (*r == ESC_CHAR)
 754         {
 755             /* Skip the control sequence's arguments */ ;
 756             /* '(' need to avoid strange 'B' letter in *Suse (if mc runs under root user) */
 757             if (*(++r) == '[' || *r == '(')
 758             {
 759                 /* strchr() matches trailing binary 0 */
 760                 while (*(++r) && strchr ("0123456789;?", *r));
 761             }
 762             else if (*r == ']')
 763             {
 764                 /*
 765                  * Skip xterm's OSC (Operating System Command)
 766                  * http://www.xfree86.org/current/ctlseqs.html
 767                  * OSC P s ; P t ST
 768                  * OSC P s ; P t BEL
 769                  */
 770                 char *new_r = r;
 771
 772                 for (; *new_r; ++new_r)
 773                 {
 774                     switch (*new_r)
 775                     {
 776                         /* BEL */
 777                     case '\a':
 778                         r = new_r;
 779                         goto osc_out;
 780                     case ESC_CHAR:
 781                         /* ST */
 782                         if (*(new_r + 1) == '\\')
 783                         {
 784                             r = new_r + 1;
 785                             goto osc_out;
 786                         }
 787                     }
 788                 }
 789               osc_out:;
 790             }
 791
 792             /*
 793              * Now we are at the last character of the sequence.
 794              * Skip it unless it's binary 0.
 795              */
 796             if (*r)
 797                 r++;
 798             continue;
 799         }
 800
 801         n = str_get_next_char (r);
 802         if (str_isprint (r))
 803         {
 804             memmove (w, r, n - r);
 805             w += n - r;
 806         }
 807         r = n;
 808     }
 809     *w = 0;
 810     return s;
 811 }
 812
 813 /* --------------------------------------------------------------------------------------------- */
 814
 815 enum compression_type
 816 get_compression_type (int fd, const char *name)
 817 {
 818     unsigned char magic[16];
 819     size_t str_len;
 820
 821     /* Read the magic signature */
 822     if (mc_read (fd, (char *) magic, 4) != 4)
 823         return COMPRESSION_NONE;
 824
 825     /* GZIP_MAGIC and OLD_GZIP_MAGIC */
 826     if (magic[0] == 037 && (magic[1] == 0213 || magic[1] == 0236))
 827     {
 828         return COMPRESSION_GZIP;
 829     }
 830
 831     /* PKZIP_MAGIC */
 832     if (magic[0] == 0120 && magic[1] == 0113 && magic[2] == 003 && magic[3] == 004)
 833     {
 834         /* Read compression type */
 835         mc_lseek (fd, 8, SEEK_SET);
 836         if (mc_read (fd, (char *) magic, 2) != 2)
 837             return COMPRESSION_NONE;
 838
 839         /* Gzip can handle only deflated (8) or stored (0) files */
 840         if ((magic[0] != 8 && magic[0] != 0) || magic[1] != 0)
 841             return COMPRESSION_NONE;
 842
 843         /* Compatible with gzip */
 844         return COMPRESSION_GZIP;
 845     }
 846
 847     /* PACK_MAGIC and LZH_MAGIC and compress magic */
 848     if (magic[0] == 037 && (magic[1] == 036 || magic[1] == 0240 || magic[1] == 0235))
 849     {
 850         /* Compatible with gzip */
 851         return COMPRESSION_GZIP;
 852     }
 853
 854     /* BZIP and BZIP2 files */
 855     if ((magic[0] == 'B') && (magic[1] == 'Z') && (magic[3] >= '1') && (magic[3] <= '9'))
 856     {
 857         switch (magic[2])
 858         {
 859         case '0':
 860             return COMPRESSION_BZIP;
 861         case 'h':
 862             return COMPRESSION_BZIP2;
 863         }
 864     }
 865
 866     /* Support for LZMA (only utils format with magic in header).
 867      * This is the default format of LZMA utils 4.32.1 and later. */
 868
 869     if (mc_read (fd, (char *) magic + 4, 2) != 2)
 870         return COMPRESSION_NONE;
 871
 872     /* LZMA utils format */
 873     if (magic[0] == 0xFF
 874         && magic[1] == 'L'
 875         && magic[2] == 'Z' && magic[3] == 'M' && magic[4] == 'A' && magic[5] == 0x00)
 876         return COMPRESSION_LZMA;
 877
 878     /* XZ compression magic */
 879     if (magic[0] == 0xFD
 880         && magic[1] == 0x37
 881         && magic[2] == 0x7A && magic[3] == 0x58 && magic[4] == 0x5A && magic[5] == 0x00)
 882         return COMPRESSION_XZ;
 883
 884     str_len = strlen (name);
 885     /* HACK: we must belive to extention of LZMA file :) ... */
 886     if ((str_len > 5 && strcmp (&name[str_len - 5], ".lzma") == 0) ||
 887         (str_len > 4 && strcmp (&name[str_len - 4], ".tlz") == 0))
 888         return COMPRESSION_LZMA;
 889
 890     return COMPRESSION_NONE;
 891 }
 892
 893 /* --------------------------------------------------------------------------------------------- */
 894
 895 const char *
 896 decompress_extension (int type)
 897 {
 898     switch (type)
 899     {
 900     case COMPRESSION_GZIP:
 901         return "/ugz" VFS_PATH_URL_DELIMITER;
 902     case COMPRESSION_BZIP:
 903         return "/ubz" VFS_PATH_URL_DELIMITER;
 904     case COMPRESSION_BZIP2:
 905         return "/ubz2" VFS_PATH_URL_DELIMITER;
 906     case COMPRESSION_LZMA:
 907         return "/ulzma" VFS_PATH_URL_DELIMITER;
 908     case COMPRESSION_XZ:
 909         return "/uxz" VFS_PATH_URL_DELIMITER;
 910     }
 911     /* Should never reach this place */
 912     fprintf (stderr, "Fatal: decompress_extension called with an unknown argument\n");
 913     return 0;
 914 }
 915
 916 /* --------------------------------------------------------------------------------------------- */
 917
 918 void
 919 wipe_password (char *passwd)
 920 {
 921     char *p = passwd;
 922
 923     if (!p)
 924         return;
 925     for (; *p; p++)
 926         *p = 0;
 927     g_free (passwd);
 928 }
 929
 930 /* --------------------------------------------------------------------------------------------- */
 931 /**
 932  * Convert "\E" -> esc character and ^x to control-x key and ^^ to ^ key
 933  * @returns a newly allocated string
 934  */
 935
 936 char *
 937 convert_controls (const char *p)
 938 {
 939     char *valcopy = g_strdup (p);
 940     char *q;
 941
 942     /* Parse the escape special character */
 943     for (q = valcopy; *p;)
 944     {
 945         if (*p == '\\')
 946         {
 947             p++;
 948             if ((*p == 'e') || (*p == 'E'))
 949             {
 950                 p++;
 951                 *q++ = ESC_CHAR;
 952             }
 953         }
 954         else
 955         {
 956             if (*p == '^')
 957             {
 958                 p++;
 959                 if (*p == '^')
 960                     *q++ = *p++;
 961                 else
 962                 {
 963                     char c = (*p | 0x20);
 964                     if (c >= 'a' && c <= 'z')
 965                     {
 966                         *q++ = c - 'a' + 1;
 967                         p++;
 968                     }
 969                     else if (*p)
 970                         p++;
 971                 }
 972             }
 973             else
 974                 *q++ = *p++;
 975         }
 976     }
 977     *q = 0;
 978     return valcopy;
 979 }
 980
 981 /* --------------------------------------------------------------------------------------------- */
 982 /**
 983  * Finds out a relative path from first to second, i.e. goes as many ..
 984  * as needed up in first and then goes down using second
 985  */
 986
 987 char *
 988 diff_two_paths (const char *first, const char *second)
 989 {
 990     char *p, *q, *r, *s, *buf = NULL;
 991     int i, j, prevlen = -1, currlen;
 992     char *my_first = NULL, *my_second = NULL;
 993
 994     my_first = resolve_symlinks (first);
 995     if (my_first == NULL)
 996         return NULL;
 997     my_second = resolve_symlinks (second);
 998     if (my_second == NULL)
 999     {
1000         g_free (my_first);
1001         return NULL;
1002     }
1003     for (j = 0; j < 2; j++)
1004     {
1005         p = my_first;
1006         q = my_second;
1007         for (;;)
1008         {
1009             r = strchr (p, PATH_SEP);
1010             s = strchr (q, PATH_SEP);
1011             if (!r || !s)
1012                 break;
1013             *r = 0;
1014             *s = 0;
1015             if (strcmp (p, q))
1016             {
1017                 *r = PATH_SEP;
1018                 *s = PATH_SEP;
1019                 break;
1020             }
1021             else
1022             {
1023                 *r = PATH_SEP;
1024                 *s = PATH_SEP;
1025             }
1026             p = r + 1;
1027             q = s + 1;
1028         }
1029         p--;
1030         for (i = 0; (p = strchr (p + 1, PATH_SEP)) != NULL; i++);
1031         currlen = (i + 1) * 3 + strlen (q) + 1;
1032         if (j)
1033         {
1034             if (currlen < prevlen)
1035                 g_free (buf);
1036             else
1037             {
1038                 g_free (my_first);
1039                 g_free (my_second);
1040                 return buf;
1041             }
1042         }
1043         p = buf = g_malloc (currlen);
1044         prevlen = currlen;
1045         for (; i >= 0; i--, p += 3)
1046             strcpy (p, "../");
1047         strcpy (p, q);
1048     }
1049     g_free (my_first);
1050     g_free (my_second);
1051     return buf;
1052 }
1053
1054 /* --------------------------------------------------------------------------------------------- */
1055 /**
1056  * If filename is NULL, then we just append PATH_SEP to the dir
1057  */
1058
1059 char *
1060 concat_dir_and_file (const char *dir, const char *file)
1061 {
1062     int i = strlen (dir);
1063
1064     if (dir[i - 1] == PATH_SEP)
1065         return g_strconcat (dir, file, (char *) NULL);
1066     else
1067         return g_strconcat (dir, PATH_SEP_STR, file, (char *) NULL);
1068 }
1069
1070 /* --------------------------------------------------------------------------------------------- */
1071 /**
1072  * Append text to GList, remove all entries with the same text
1073  */
1074
1075 GList *
1076 list_append_unique (GList * list, char *text)
1077 {
1078     GList *lc_link;
1079
1080     /*
1081      * Go to the last position and traverse the list backwards
1082      * starting from the second last entry to make sure that we
1083      * are not removing the current link.
1084      */
1085     list = g_list_append (list, text);
1086     list = g_list_last (list);
1087     lc_link = g_list_previous (list);
1088
1089     while (lc_link != NULL)
1090     {
1091         GList *newlink;
1092
1093         newlink = g_list_previous (lc_link);
1094         if (strcmp ((char *) lc_link->data, text) == 0)
1095         {
1096             GList *tmp;
1097
1098             g_free (lc_link->data);
1099             tmp = g_list_remove_link (list, lc_link);
1100             g_list_free_1 (lc_link);
1101         }
1102         lc_link = newlink;
1103     }
1104
1105     return list;
1106 }
1107
1108 /* --------------------------------------------------------------------------------------------- */
1109 /* Following code heavily borrows from libiberty, mkstemps.c */
1110 /*
1111  * Arguments:
1112  * pname (output) - pointer to the name of the temp file (needs g_free).
1113  *                  NULL if the function fails.
1114  * prefix - part of the filename before the random part.
1115  *          Prepend $TMPDIR or /tmp if there are no path separators.
1116  * suffix - if not NULL, part of the filename after the random part.
1117  *
1118  * Result:
1119  * handle of the open file or -1 if couldn't open any.
1120  */
1121
1122 int
1123 mc_mkstemps (char **pname, const char *prefix, const char *suffix)
1124 {
1125     static const char letters[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
1126     static unsigned long value;
1127     struct timeval tv;
1128     char *tmpbase;
1129     char *tmpname;
1130     char *XXXXXX;
1131     int count;
1132
1133     if (strchr (prefix, PATH_SEP) == NULL)
1134     {
1135         /* Add prefix first to find the position of XXXXXX */
1136         tmpbase = concat_dir_and_file (mc_tmpdir (), prefix);
1137     }
1138     else
1139     {
1140         tmpbase = g_strdup (prefix);
1141     }
1142
1143     tmpname = g_strconcat (tmpbase, "XXXXXX", suffix, (char *) NULL);
1144     *pname = tmpname;
1145     XXXXXX = &tmpname[strlen (tmpbase)];
1146     g_free (tmpbase);
1147
1148     /* Get some more or less random data.  */
1149     gettimeofday (&tv, NULL);
1150     value += (tv.tv_usec << 16) ^ tv.tv_sec ^ getpid ();
1151
1152     for (count = 0; count < TMP_MAX; ++count)
1153     {
1154         unsigned long v = value;
1155         int fd;
1156
1157         /* Fill in the random bits.  */
1158         XXXXXX[0] = letters[v % 62];
1159         v /= 62;
1160         XXXXXX[1] = letters[v % 62];
1161         v /= 62;
1162         XXXXXX[2] = letters[v % 62];
1163         v /= 62;
1164         XXXXXX[3] = letters[v % 62];
1165         v /= 62;
1166         XXXXXX[4] = letters[v % 62];
1167         v /= 62;
1168         XXXXXX[5] = letters[v % 62];
1169
1170         fd = open (tmpname, O_RDWR | O_CREAT | O_TRUNC | O_EXCL, S_IRUSR | S_IWUSR);
1171         if (fd >= 0)
1172         {
1173             /* Successfully created.  */
1174             return fd;
1175         }
1176
1177         /* This is a random value.  It is only necessary that the next
1178            TMP_MAX values generated by adding 7777 to VALUE are different
1179            with (module 2^32).  */
1180         value += 7777;
1181     }
1182
1183     /* Unsuccessful. Free the filename. */
1184     g_free (tmpname);
1185     *pname = NULL;
1186
1187     return -1;
1188 }
1189
1190 /* --------------------------------------------------------------------------------------------- */
1191 /**
1192  * Read and restore position for the given filename.
1193  * If there is no stored data, return line 1 and col 0.
1194  */
1195
1196 void
1197 load_file_position (const char *filename, long *line, long *column, off_t * offset,
1198                     GArray ** bookmarks)
1199 {
1200     char *fn;
1201     FILE *f;
1202     char buf[MC_MAXPATHLEN + 100];
1203     const size_t len = strlen (filename);
1204
1205     /* defaults */
1206     *line = 1;
1207     *column = 0;
1208     *offset = 0;
1209
1210     /* open file with positions */
1211     fn = g_build_filename (mc_config_get_cache_path (), MC_FILEPOS_FILE, NULL);
1212     f = fopen (fn, "r");
1213     g_free (fn);
1214     if (f == NULL)
1215         return;
1216
1217     /* prepare array for serialized bookmarks */
1218     *bookmarks = g_array_sized_new (FALSE, FALSE, sizeof (size_t), MAX_SAVED_BOOKMARKS);
1219
1220     while (fgets (buf, sizeof (buf), f) != NULL)
1221     {
1222         const char *p;
1223         gchar **pos_tokens;
1224
1225         /* check if the filename matches the beginning of string */
1226         if (strncmp (buf, filename, len) != 0)
1227             continue;
1228
1229         /* followed by single space */
1230         if (buf[len] != ' ')
1231             continue;
1232
1233         /* and string without spaces */
1234         p = &buf[len + 1];
1235         if (strchr (p, ' ') != NULL)
1236             continue;
1237
1238         pos_tokens = g_strsplit (p, ";", 3 + MAX_SAVED_BOOKMARKS);
1239         if (pos_tokens[0] == NULL)
1240         {
1241             *line = 1;
1242             *column = 0;
1243             *offset = 0;
1244         }
1245         else
1246         {
1247             *line = strtol (pos_tokens[0], NULL, 10);
1248             if (pos_tokens[1] == NULL)
1249             {
1250                 *column = 0;
1251                 *offset = 0;
1252             }
1253             else
1254             {
1255                 *column = strtol (pos_tokens[1], NULL, 10);
1256                 if (pos_tokens[2] == NULL)
1257                     *offset = 0;
1258                 else
1259                 {
1260                     size_t i;
1261
1262                     *offset = strtoll (pos_tokens[2], NULL, 10);
1263
1264                     for (i = 0; i < MAX_SAVED_BOOKMARKS && pos_tokens[3 + i] != NULL; i++)
1265                     {
1266                         size_t val;
1267
1268                         val = strtoul (pos_tokens[3 + i], NULL, 10);
1269                         g_array_append_val (*bookmarks, val);
1270                     }
1271                 }
1272             }
1273         }
1274
1275         g_strfreev (pos_tokens);
1276     }
1277
1278     fclose (f);
1279 }
1280
1281 /* --------------------------------------------------------------------------------------------- */
1282 /**
1283  * Save position for the given file
1284  */
1285
1286 void
1287 save_file_position (const char *filename, long line, long column, off_t offset, GArray * bookmarks)
1288 {
1289     static size_t filepos_max_saved_entries = 0;
1290     char *fn, *tmp_fn;
1291     FILE *f, *tmp_f;
1292     char buf[MC_MAXPATHLEN + 100];
1293     size_t i;
1294     const size_t len = strlen (filename);
1295     gboolean src_error = FALSE;
1296
1297     if (filepos_max_saved_entries == 0)
1298         filepos_max_saved_entries = mc_config_get_int (mc_main_config, CONFIG_APP_SECTION,
1299                                                        "filepos_max_saved_entries", 1024);
1300
1301     fn = g_build_filename (mc_config_get_cache_path (), MC_FILEPOS_FILE, NULL);
1302     if (fn == NULL)
1303         goto early_error;
1304
1305     mc_util_make_backup_if_possible (fn, TMP_SUFFIX);
1306
1307     /* open file */
1308     f = fopen (fn, "w");
1309     if (f == NULL)
1310         goto open_target_error;
1311
1312     tmp_fn = g_strdup_printf ("%s" TMP_SUFFIX, fn);
1313     tmp_f = fopen (tmp_fn, "r");
1314     if (tmp_f == NULL)
1315     {
1316         src_error = TRUE;
1317         goto open_source_error;
1318     }
1319
1320     /* put the new record */
1321     if (line != 1 || column != 0 || bookmarks != NULL)
1322     {
1323         if (fprintf (f, "%s %ld;%ld;%" PRIuMAX, filename, line, column, (uintmax_t) offset) < 0)
1324             goto write_position_error;
1325         if (bookmarks != NULL)
1326             for (i = 0; i < bookmarks->len && i < MAX_SAVED_BOOKMARKS; i++)
1327                 if (fprintf (f, ";%zu", g_array_index (bookmarks, size_t, i)) < 0)
1328                     goto write_position_error;
1329
1330         if (fprintf (f, "\n") < 0)
1331             goto write_position_error;
1332     }
1333
1334     i = 1;
1335     while (fgets (buf, sizeof (buf), tmp_f) != NULL)
1336     {
1337         if (buf[len] == ' ' && strncmp (buf, filename, len) == 0
1338             && strchr (&buf[len + 1], ' ') == NULL)
1339             continue;
1340
1341         fprintf (f, "%s", buf);
1342         if (++i > filepos_max_saved_entries)
1343             break;
1344     }
1345
1346   write_position_error:
1347     fclose (tmp_f);
1348   open_source_error:
1349     g_free (tmp_fn);
1350     fclose (f);
1351     if (src_error)
1352         mc_util_restore_from_backup_if_possible (fn, TMP_SUFFIX);
1353     else
1354         mc_util_unlink_backup_if_possible (fn, TMP_SUFFIX);
1355   open_target_error:
1356     g_free (fn);
1357   early_error:
1358     if (bookmarks != NULL)
1359         g_array_free (bookmarks, TRUE);
1360 }
1361
1362 /* --------------------------------------------------------------------------------------------- */
1363
1364 extern int
1365 ascii_alpha_to_cntrl (int ch)
1366 {
1367     if ((ch >= ASCII_A && ch <= ASCII_Z) || (ch >= ASCII_a && ch <= ASCII_z))
1368     {
1369         ch &= 0x1f;
1370     }
1371     return ch;
1372 }
1373
1374 /* --------------------------------------------------------------------------------------------- */
1375
1376 const char *
1377 Q_ (const char *s)
1378 {
1379     const char *result, *sep;
1380
1381     result = _(s);
1382     sep = strchr (result, '|');
1383     return (sep != NULL) ? sep + 1 : result;
1384 }
1385
1386 /* --------------------------------------------------------------------------------------------- */
1387
1388 gboolean
1389 mc_util_make_backup_if_possible (const char *file_name, const char *backup_suffix)
1390 {
1391     struct stat stat_buf;
1392     char *backup_path;
1393     gboolean ret;
1394     if (!exist_file (file_name))
1395         return FALSE;
1396
1397     backup_path = g_strdup_printf ("%s%s", file_name, backup_suffix);
1398
1399     if (backup_path == NULL)
1400         return FALSE;
1401
1402     ret = mc_util_write_backup_content (file_name, backup_path);
1403
1404     if (ret)
1405     {
1406         /* Backup file will have same ownership with main file. */
1407         if (stat (file_name, &stat_buf) == 0)
1408             chmod (backup_path, stat_buf.st_mode);
1409         else
1410             chmod (backup_path, S_IRUSR | S_IWUSR);
1411     }
1412
1413     g_free (backup_path);
1414
1415     return ret;
1416 }
1417
1418 /* --------------------------------------------------------------------------------------------- */
1419
1420 gboolean
1421 mc_util_restore_from_backup_if_possible (const char *file_name, const char *backup_suffix)
1422 {
1423     gboolean ret;
1424     char *backup_path;
1425
1426     backup_path = g_strdup_printf ("%s%s", file_name, backup_suffix);
1427     if (backup_path == NULL)
1428         return FALSE;
1429
1430     ret = mc_util_write_backup_content (backup_path, file_name);
1431     g_free (backup_path);
1432
1433     return ret;
1434 }
1435
1436 /* --------------------------------------------------------------------------------------------- */
1437
1438 gboolean
1439 mc_util_unlink_backup_if_possible (const char *file_name, const char *backup_suffix)
1440 {
1441     char *backup_path;
1442
1443     backup_path = g_strdup_printf ("%s%s", file_name, backup_suffix);
1444     if (backup_path == NULL)
1445         return FALSE;
1446
1447     if (exist_file (backup_path))
1448         mc_unlink (backup_path);
1449
1450     g_free (backup_path);
1451     return TRUE;
1452 }
1453
1454 /* --------------------------------------------------------------------------------------------- */
1455 /**
1456  * partly taken from dcigettext.c, returns "" for default locale
1457  * value should be freed by calling function g_free()
1458  */
1459
1460 char *
1461 guess_message_value (void)
1462 {
1463     static const char *const var[] = {
1464         /* Setting of LC_ALL overwrites all other.  */
1465         /* Do not use LANGUAGE for check user locale and drowing hints */
1466         "LC_ALL",
1467         /* Next comes the name of the desired category.  */
1468         "LC_MESSAGES",
1469         /* Last possibility is the LANG environment variable.  */
1470         "LANG",
1471         /* NULL exit loops */
1472         NULL
1473     };
1474
1475     unsigned i = 0;
1476     const char *locale = NULL;
1477
1478     while (var[i] != NULL)
1479     {
1480         locale = getenv (var[i]);
1481         if (locale != NULL && locale[0] != '\0')
1482             break;
1483         i++;
1484     }
1485
1486     if (locale == NULL)
1487         locale = "";
1488
1489     return g_strdup (locale);
1490 }
1491
1492 /* --------------------------------------------------------------------------------------------- */