root/libltdl/argz.c

/* */

DEFINITIONS

1. argz_append
2. argz_create_sep
3. argz_insert
4. argz_next
5. argz_stringify

   1 /* argz.c -- argz implementation for non-glibc systems
   2 
   3    Copyright (C) 2004, 2006, 2007, 2008 Free Software Foundation, Inc.
   4    Written by Gary V. Vaughan, 2004
   5 
   6    NOTE: The canonical source of this file is maintained with the
   7    GNU Libtool package.  Report bugs to bug-libtool@gnu.org.
   8 
   9 GNU Libltdl is free software; you can redistribute it and/or
  10 modify it under the terms of the GNU Lesser General Public
  11 License as published by the Free Software Foundation; either
  12 version 2 of the License, or (at your option) any later version.
  13 
  14 As a special exception to the GNU Lesser General Public License,
  15 if you distribute this file as part of a program or library that
  16 is built using GNU Libtool, you may include this file under the
  17 same distribution terms that you use for the rest of that program.
  18 
  19 GNU Libltdl is distributed in the hope that it will be useful,
  20 but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 GNU Lesser General Public License for more details.
  23 
  24 You should have received a copy of the GNU Lesser General Public
  25 License along with GNU Libltdl; see the file COPYING.LIB.  If not, a
  26 copy can be downloaded from  http://www.gnu.org/licenses/lgpl.html,
  27 or obtained by writing to the Free Software Foundation, Inc.,
  28 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  29 */
  30 
  31 #if defined(LTDL) && defined LT_CONFIG_H
  32 #  include LT_CONFIG_H
  33 #else
  34 #  include <config.h>
  35 #endif
  36 
  37 #include <argz.h>
  38 
  39 #include <assert.h>
  40 #include <stddef.h>
  41 #include <stdlib.h>
  42 #include <sys/types.h>
  43 #include <errno.h>
  44 #include <string.h>
  45 
  46 #define EOS_CHAR '\0'
  47 
  48 error_t
  49 argz_append (char **pargz, size_t *pargz_len, const char *buf, size_t buf_len)
  50 {
  51   size_t argz_len;
  52   char  *argz;
  53 
  54   assert (pargz);
  55   assert (pargz_len);
  56   assert ((*pargz && *pargz_len) || (!*pargz && !*pargz_len));
  57 
  58   /* If nothing needs to be appended, no more work is required.  */
  59   if (buf_len == 0)
  60     return 0;
  61 
  62   /* Ensure there is enough room to append BUF_LEN.  */
  63   argz_len = *pargz_len + buf_len;
  64   argz = (char *) realloc (*pargz, argz_len);
  65   if (!argz)
  66     return ENOMEM;
  67 
  68   /* Copy characters from BUF after terminating '\0' in ARGZ.  */
  69   memcpy (argz + *pargz_len, buf, buf_len);
  70 
  71   /* Assign new values.  */
  72   *pargz = argz;
  73   *pargz_len = argz_len;
  74 
  75   return 0;
  76 }
  77 
  78 
  79 error_t
  80 argz_create_sep (const char *str, int delim, char **pargz, size_t *pargz_len)
  81 {
  82   size_t argz_len;
  83   char *argz = 0;
  84 
  85   assert (str);
  86   assert (pargz);
  87   assert (pargz_len);
  88 
  89   /* Make a copy of STR, but replacing each occurrence of
  90      DELIM with '\0'.  */
  91   argz_len = 1+ strlen (str);
  92   if (argz_len)
  93     {
  94       const char *p;
  95       char *q;
  96 
  97       argz = (char *) malloc (argz_len);
  98       if (!argz)
  99         return ENOMEM;
 100 
 101       for (p = str, q = argz; *p != EOS_CHAR; ++p)
 102         {
 103           if (*p == delim)
 104             {
 105               /* Ignore leading delimiters, and fold consecutive
 106                  delimiters in STR into a single '\0' in ARGZ.  */
 107               if ((q > argz) && (q[-1] != EOS_CHAR))
 108                 *q++ = EOS_CHAR;
 109               else
 110                 --argz_len;
 111             }
 112           else
 113             *q++ = *p;
 114         }
 115       /* Copy terminating EOS_CHAR.  */
 116       *q = *p;
 117     }
 118 
 119   /* If ARGZ_LEN has shrunk to nothing, release ARGZ's memory.  */
 120   if (!argz_len)
 121     argz = (free (argz), (char *) 0);
 122 
 123   /* Assign new values.  */
 124   *pargz = argz;
 125   *pargz_len = argz_len;
 126 
 127   return 0;
 128 }
 129 
 130 
 131 error_t
 132 argz_insert (char **pargz, size_t *pargz_len, char *before, const char *entry)
 133 {
 134   assert (pargz);
 135   assert (pargz_len);
 136   assert (entry && *entry);
 137 
 138   /* No BEFORE address indicates ENTRY should be inserted after the
 139      current last element.  */
 140   if (!before)
 141     return argz_append (pargz, pargz_len, entry, 1+ strlen (entry));
 142 
 143   /* This probably indicates a programmer error, but to preserve
 144      semantics, scan back to the start of an entry if BEFORE points
 145      into the middle of it.  */
 146   while ((before > *pargz) && (before[-1] != EOS_CHAR))
 147     --before;
 148 
 149   {
 150     size_t entry_len    = 1+ strlen (entry);
 151     size_t argz_len     = *pargz_len + entry_len;
 152     size_t offset       = before - *pargz;
 153     char   *argz        = (char *) realloc (*pargz, argz_len);
 154 
 155     if (!argz)
 156       return ENOMEM;
 157 
 158     /* Make BEFORE point to the equivalent offset in ARGZ that it
 159        used to have in *PARGZ incase realloc() moved the block.  */
 160     before = argz + offset;
 161 
 162     /* Move the ARGZ entries starting at BEFORE up into the new
 163        space at the end -- making room to copy ENTRY into the
 164        resulting gap.  */
 165     memmove (before + entry_len, before, *pargz_len - offset);
 166     memcpy  (before, entry, entry_len);
 167 
 168     /* Assign new values.  */
 169     *pargz = argz;
 170     *pargz_len = argz_len;
 171   }
 172 
 173   return 0;
 174 }
 175 
 176 
 177 char *
 178 argz_next (char *argz, size_t argz_len, const char *entry)
 179 {
 180   assert ((argz && argz_len) || (!argz && !argz_len));
 181 
 182   if (entry)
 183     {
 184       /* Either ARGZ/ARGZ_LEN is empty, or ENTRY points into an address
 185          within the ARGZ vector.  */
 186       assert ((!argz && !argz_len)
 187               || ((argz <= entry) && (entry < (argz + argz_len))));
 188 
 189       /* Move to the char immediately after the terminating
 190          '\0' of ENTRY.  */
 191       entry = 1+ strchr (entry, EOS_CHAR);
 192 
 193       /* Return either the new ENTRY, or else NULL if ARGZ is
 194          exhausted.  */
 195       return (entry >= argz + argz_len) ? 0 : (char *) entry;
 196     }
 197   else
 198     {
 199       /* This should probably be flagged as a programmer error,
 200          since starting an argz_next loop with the iterator set
 201          to ARGZ is safer.  To preserve semantics, handle the NULL
 202          case by returning the start of ARGZ (if any).  */
 203       if (argz_len > 0)
 204         return argz;
 205       else
 206         return 0;
 207     }
 208 }
 209 
 210 
 211 void
 212 argz_stringify (char *argz, size_t argz_len, int sep)
 213 {
 214   assert ((argz && argz_len) || (!argz && !argz_len));
 215 
 216   if (sep)
 217     {
 218       --argz_len;               /* don't stringify the terminating EOS */
 219       while (--argz_len > 0)
 220         {
 221           if (argz[argz_len] == EOS_CHAR)
 222             argz[argz_len] = sep;
 223         }
 224     }
 225 }
 226 

/* */