stringlib.c

   1 /* stringlib.c - Miscellaneous string functions. */
   2
   3 /* Copyright (C) 1996-2009 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "config.h"
  22
  23 #include "bashtypes.h"
  24
  25 #if defined (HAVE_UNISTD_H)
  26 #  include <unistd.h>
  27 #endif
  28
  29 #include "bashansi.h"
  30 #include <stdio.h>
  31 #include "chartypes.h"
  32
  33 #include "shell.h"
  34 #include "pathexp.h"
  35
  36 #include <glob/glob.h>
  37
  38 #if defined (EXTENDED_GLOB)
  39 #  include <glob/strmatch.h>
  40 #endif
  41
  42 /* **************************************************************** */
  43 /*                                                                  */
  44 /*              Functions to manage arrays of strings               */
  45 /*                                                                  */
  46 /* **************************************************************** */
  47
  48 /* Find STRING in ALIST, a list of string key/int value pairs.  If FLAGS
  49    is 1, STRING is treated as a pattern and matched using strmatch. */
  50 int
  51 find_string_in_alist (string, alist, flags)
  52      char *string;
  53      STRING_INT_ALIST *alist;
  54      int flags;
  55 {
  56   register int i;
  57   int r;
  58
  59   for (i = r = 0; alist[i].word; i++)
  60     {
  61 #if defined (EXTENDED_GLOB)
  62       if (flags)
  63         r = strmatch (alist[i].word, string, FNM_EXTMATCH) != FNM_NOMATCH;
  64       else
  65 #endif
  66         r = STREQ (string, alist[i].word);
  67
  68       if (r)
  69         return (alist[i].token);
  70     }
  71   return -1;
  72 }
  73
  74 /* Find TOKEN in ALIST, a list of string/int value pairs.  Return the
  75    corresponding string.  Allocates memory for the returned
  76    string.  FLAGS is currently ignored, but reserved. */
  77 char *
  78 find_token_in_alist (token, alist, flags)
  79      int token;
  80      STRING_INT_ALIST *alist;
  81      int flags;
  82 {
  83   register int i;
  84
  85   for (i = 0; alist[i].word; i++)
  86     {
  87       if (alist[i].token == token)
  88         return (savestring (alist[i].word));
  89     }
  90   return ((char *)NULL);
  91 }
  92
  93 int
  94 find_index_in_alist (string, alist, flags)
  95      char *string;
  96      STRING_INT_ALIST *alist;
  97      int flags;
  98 {
  99   register int i;
 100   int r;
 101
 102   for (i = r = 0; alist[i].word; i++)
 103     {
 104 #if defined (EXTENDED_GLOB)
 105       if (flags)
 106         r = strmatch (alist[i].word, string, FNM_EXTMATCH) != FNM_NOMATCH;
 107       else
 108 #endif
 109         r = STREQ (string, alist[i].word);
 110
 111       if (r)
 112         return (i);
 113     }
 114
 115   return -1;
 116 }
 117
 118 /* **************************************************************** */
 119 /*                                                                  */
 120 /*                  String Management Functions                     */
 121 /*                                                                  */
 122 /* **************************************************************** */
 123
 124 /* Cons a new string from STRING starting at START and ending at END,
 125    not including END. */
 126 char *
 127 substring (string, start, end)
 128      const char *string;
 129      int start, end;
 130 {
 131   register int len;
 132   register char *result;
 133
 134   len = end - start;
 135   result = (char *)xmalloc (len + 1);
 136   memcpy (result, string + start, len);
 137   result[len] = '\0';
 138   return (result);
 139 }
 140
 141 /* Replace occurrences of PAT with REP in STRING.  If GLOBAL is non-zero,
 142    replace all occurrences, otherwise replace only the first.
 143    This returns a new string; the caller should free it. */
 144 char *
 145 strsub (string, pat, rep, global)
 146      char *string, *pat, *rep;
 147      int global;
 148 {
 149   int patlen, replen, templen, tempsize, repl, i;
 150   char *temp, *r;
 151
 152   patlen = strlen (pat);
 153   replen = strlen (rep);
 154   for (temp = (char *)NULL, i = templen = tempsize = 0, repl = 1; string[i]; )
 155     {
 156       if (repl && STREQN (string + i, pat, patlen))
 157         {
 158           if (replen)
 159             RESIZE_MALLOCED_BUFFER (temp, templen, replen, tempsize, (replen * 2));
 160
 161           for (r = rep; *r; )   /* can rep == "" */
 162             temp[templen++] = *r++;
 163
 164           i += patlen ? patlen : 1;     /* avoid infinite recursion */
 165           repl = global != 0;
 166         }
 167       else
 168         {
 169           RESIZE_MALLOCED_BUFFER (temp, templen, 1, tempsize, 16);
 170           temp[templen++] = string[i++];
 171         }
 172     }
 173   if (temp)
 174     temp[templen] = 0;
 175   else
 176     temp = savestring (string);
 177   return (temp);
 178 }
 179
 180 /* Replace all instances of C in STRING with TEXT.  TEXT may be empty or
 181    NULL.  If DO_GLOB is non-zero, we quote the replacement text for
 182    globbing.  Backslash may be used to quote C. */
 183 char *
 184 strcreplace (string, c, text, do_glob)
 185      char *string;
 186      int c;
 187      const char *text;
 188      int do_glob;
 189 {
 190   char *ret, *p, *r, *t;
 191   int len, rlen, ind, tlen;
 192
 193   len = STRLEN (text);
 194   rlen = len + strlen (string) + 2;
 195   ret = (char *)xmalloc (rlen);
 196
 197   for (p = string, r = ret; p && *p; )
 198     {
 199       if (*p == c)
 200         {
 201           if (len)
 202             {
 203               ind = r - ret;
 204               if (do_glob && (glob_pattern_p (text) || strchr (text, '\\')))
 205                 {
 206                   t = quote_globbing_chars (text);
 207                   tlen = strlen (t);
 208                   RESIZE_MALLOCED_BUFFER (ret, ind, tlen, rlen, rlen);
 209                   r = ret + ind;        /* in case reallocated */
 210                   strcpy (r, t);
 211                   r += tlen;
 212                   free (t);
 213                 }
 214               else
 215                 {
 216                   RESIZE_MALLOCED_BUFFER (ret, ind, len, rlen, rlen);
 217                   r = ret + ind;        /* in case reallocated */
 218                   strcpy (r, text);
 219                   r += len;
 220                 }
 221             }
 222           p++;
 223           continue;
 224         }
 225
 226       if (*p == '\\' && p[1] == c)
 227         p++;
 228
 229       ind = r - ret;
 230       RESIZE_MALLOCED_BUFFER (ret, ind, 2, rlen, rlen);
 231       r = ret + ind;                    /* in case reallocated */
 232       *r++ = *p++;
 233     }
 234   *r = '\0';
 235
 236   return ret;
 237 }
 238
 239 #ifdef INCLUDE_UNUSED
 240 /* Remove all leading whitespace from STRING.  This includes
 241    newlines.  STRING should be terminated with a zero. */
 242 void
 243 strip_leading (string)
 244      char *string;
 245 {
 246   char *start = string;
 247
 248   while (*string && (whitespace (*string) || *string == '\n'))
 249     string++;
 250
 251   if (string != start)
 252     {
 253       int len = strlen (string);
 254       FASTCOPY (string, start, len);
 255       start[len] = '\0';
 256     }
 257 }
 258 #endif
 259
 260 /* Remove all trailing whitespace from STRING.  This includes
 261    newlines.  If NEWLINES_ONLY is non-zero, only trailing newlines
 262    are removed.  STRING should be terminated with a zero. */
 263 void
 264 strip_trailing (string, len, newlines_only)
 265      char *string;
 266      int len;
 267      int newlines_only;
 268 {
 269   while (len >= 0)
 270     {
 271       if ((newlines_only && string[len] == '\n') ||
 272           (!newlines_only && whitespace (string[len])))
 273         len--;
 274       else
 275         break;
 276     }
 277   string[len + 1] = '\0';
 278 }
 279
 280 /* A wrapper for bcopy that can be prototyped in general.h */
 281 void
 282 xbcopy (s, d, n)
 283      char *s, *d;
 284      int n;
 285 {
 286   FASTCOPY (s, d, n);
 287 }