stdlib/setenv-fbsd.c

   1 /*
   2  * Copyright (c) 1987, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)setenv.c    8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD: src/lib/libc/stdlib/setenv.c,v 1.9 2002/03/22 21:53:10 obrien Exp $");
  39
  40 #include <stddef.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <crt_externs.h>
  44 #include <errno.h>
  45 #include <sys/types.h>
  46 #include <fcntl.h>
  47 #include <malloc/malloc.h>
  48
  49 #define ZONE_OWNS_PTR(zone, ptr)        (malloc_zone_from_ptr((ptr)) == zone)
  50
  51 extern malloc_zone_t *__zone0;
  52 extern void __malloc_check_env_name(const char *);
  53
  54 __private_extern__ char *__findenv(const char *, int *, char **);
  55 __private_extern__ int __setenv(const char *, const char *, int, int, char ***, malloc_zone_t *);
  56 __private_extern__ void __unsetenv(const char *, char **, malloc_zone_t *);
  57
  58 #ifndef BUILDING_VARIANT
  59 /*
  60  * Create the environment malloc zone and give it a recognizable name.
  61  */
  62 __private_extern__ int
  63 init__zone0(int should_set_errno)
  64 {
  65         if (__zone0) return (0);
  66
  67         __zone0 = malloc_create_zone(0, 0);
  68         if (!__zone0) {
  69                 if (should_set_errno) {
  70                         errno = ENOMEM;
  71                 }
  72                 return (-1);
  73         }
  74         malloc_set_zone_name(__zone0, "environ");
  75         return (0);
  76 }
  77
  78 /*
  79  * The copy flag may have 3 values:
  80  *  1 - make a copy of the name/value pair
  81  *  0 - take the name as a user-supplied name=value string
  82  * -1 - like 0, except we copy of the name=value string in name
  83  */
  84 __private_extern__ int
  85 __setenv(name, value, rewrite, copy, environp, envz)
  86         const char *name;
  87         const char *value;
  88         int rewrite, copy;
  89         char ***environp;
  90         malloc_zone_t *envz;
  91 {
  92         char *c;
  93         int offset;
  94
  95         if ((c = __findenv(name, &offset, *environp))) { /* find if already exists */
  96                 char *e;
  97                 if (!rewrite)
  98                         return (0);
  99                 /*
 100                  * In UNIX03, we can overwrite only if we allocated the
 101                  * string.  Then we can realloc it if it is too small.
 102                  */
 103                 e = (*environp)[offset];
 104                 if (copy > 0 && ZONE_OWNS_PTR(envz, e)) {
 105                         size_t l_value = strlen(value);
 106                         if (strlen(c) < l_value) {      /* old smaller; resize*/
 107                                 char *r;
 108                                 size_t len = c - e;
 109                                 if ((r = realloc(e, l_value + len + 1)) == NULL)
 110                                         return (-1);
 111                                 if (r != e) {
 112                                         (*environp)[offset] = r;
 113                                         c = r + len;
 114                                 }
 115                         }
 116                         while ( (*c++ = *value++) );
 117                         return (0);
 118                 }
 119         } else {                                        /* create new slot */
 120                 int cnt;
 121                 char **p;
 122
 123                 for (p = *environp, cnt = 0; *p; ++p, ++cnt);
 124                 if (ZONE_OWNS_PTR(envz, *environp)) {   /* just increase size */
 125                         p = (char **)realloc((char *)*environp,
 126                             (size_t)(sizeof(char *) * (cnt + 2)));
 127                         if (!p)
 128                                 return (-1);
 129                         *environp = p;
 130                 }
 131                 else {                          /* get new space */
 132                                                 /* copy old entries into it */
 133                         p = malloc_zone_malloc(envz, (size_t)(sizeof(char *) * (cnt + 2)));
 134                         if (!p)
 135                                 return (-1);
 136                         bcopy(*environp, p, cnt * sizeof(char *));
 137                         *environp = p;
 138                 }
 139                 (*environp)[cnt + 1] = NULL;
 140                 offset = cnt;
 141         }
 142         /* For non Unix03, or UnixO3 setenv(), we make a copy of the user's
 143          * strings.  For Unix03 putenv(), we put the string directly in
 144          * the environment. */
 145         if (copy > 0) {
 146                 for (c = (char *)name; *c && *c != '='; ++c);   /* no `=' in name */
 147                 if (!((*environp)[offset] =                     /* name + `=' + value */
 148                     malloc_zone_malloc(envz, (size_t)((int)(c - name) + strlen(value) + 2))))
 149                         return (-1);
 150                 for (c = (*environp)[offset]; (*c = *name++) && *c != '='; ++c);
 151                 for (*c++ = '='; (*c++ = *value++); );
 152         } else {
 153                 /* the legacy behavior copies the string */
 154                 if (copy < 0) {
 155                         size_t len = strlen(name);
 156                         if((c = malloc_zone_malloc(envz, len + 1)) == NULL)
 157                                 return (-1);
 158                         memcpy(c, name, len + 1);
 159                         name = c;
 160                 }
 161                 /* if we malloc-ed the previous value, free it first */
 162                 if ((*environp)[offset] != NULL && ZONE_OWNS_PTR(envz, (*environp)[offset]))
 163                         free((*environp)[offset]);
 164                 (*environp)[offset] = (char *)name;
 165         }
 166         return (0);
 167 }
 168
 169 __private_extern__ void
 170 __unsetenv(const char *name, char **environ, malloc_zone_t *envz)
 171 {
 172         char **p;
 173         int offset;
 174
 175         while (__findenv(name, &offset, environ)) { /* if set multiple times */
 176                 /* if we malloc-ed it, free it first */
 177                 if (ZONE_OWNS_PTR(envz, environ[offset]))
 178                         free(environ[offset]);
 179                 for (p = &environ[offset];; ++p)
 180                         if (!(*p = *(p + 1)))
 181                                 break;
 182         }
 183 }
 184
 185 /****************************************************************************/
 186 /*
 187  * _allocenvstate -- SPI that creates a new state (opaque)
 188  */
 189 void *
 190 _allocenvstate(void)
 191 {
 192         malloc_zone_t *zone;
 193         zone = malloc_create_zone(1000 /* unused */, 0 /* unused */);
 194         if (zone) {
 195                 malloc_set_zone_name(zone, "environ");
 196         }
 197         return (void *)zone;
 198 }
 199
 200 /*
 201  * _copyenv -- SPI that copies a NULL-tereminated char * array in a newly
 202  * allocated buffer, compatible with the other SPI env routines.  If env
 203  * is NULL, a char * array composed of a single NULL is returned.  NULL
 204  * is returned on error.  (This isn't needed anymore, as __setenv will
 205  * automatically make a copy in the zone.)
 206  */
 207 char **
 208 _copyenv(char **env)
 209 {
 210         char **p;
 211         int cnt = 1;
 212
 213         if (env)
 214                 for (p = env; *p; ++p, ++cnt);
 215         p = (char **)malloc((size_t)(sizeof(char *) * cnt));
 216         if (!p)
 217                 return (NULL);
 218         if (env)
 219                 bcopy(env, p, cnt * sizeof(char *));
 220         else
 221                 *p = NULL;
 222         return p;
 223 }
 224
 225 /*
 226  * _deallocenvstate -- SPI that frees all the memory associated with the state
 227  * and all allocated strings, including the environment array itself if it
 228  * was copied.
 229  */
 230 int
 231 _deallocenvstate(void *state)
 232 {
 233         malloc_zone_t *envz;
 234
 235         if (!(envz = (malloc_zone_t *)state) || envz == __zone0) {
 236                 errno = EINVAL;
 237                 return -1;
 238         }
 239         malloc_destroy_zone(envz);
 240         return 0;
 241 }
 242
 243 /*
 244  * setenvp -- SPI using an arbitrary pointer to string array and an env state,
 245  * created by _allocenvstate().  Initial checking is not done.
 246  *
 247  *      Set the value of the environmental variable "name" to be
 248  *      "value".  If rewrite is set, replace any current value.
 249  */
 250 int
 251 _setenvp(const char *name, const char *value, int rewrite, char ***envp, void *state)
 252 {
 253         if (init__zone0(1)) return (-1);
 254         return (__setenv(name, value, rewrite, 1, envp, (state ? (malloc_zone_t *)state : __zone0)));
 255 }
 256
 257 /*
 258  * unsetenv(name) -- SPI using an arbitrary pointer to string array and an env
 259  * state, created by _allocenvstate().  Initial checking is not done.
 260  *
 261  *      Delete environmental variable "name".
 262  */
 263 int
 264 _unsetenvp(const char *name, char ***envp, void *state)
 265 {
 266         if (init__zone0(1)) return (-1);
 267         __unsetenv(name, *envp, (state ? (malloc_zone_t *)state : __zone0));
 268         return 0;
 269 }
 270
 271 #endif /* !BUILD_VARIANT */
 272
 273 /*
 274  * setenv --
 275  *      Set the value of the environmental variable "name" to be
 276  *      "value".  If rewrite is set, replace any current value.
 277  */
 278 int
 279 setenv(name, value, rewrite)
 280         const char *name;
 281         const char *value;
 282         int rewrite;
 283 {
 284         /* no null ptr or empty str */
 285         if(name == NULL || *name == 0) {
 286                 errno = EINVAL;
 287                 return (-1);
 288         }
 289
 290 #if __DARWIN_UNIX03
 291         /* no '=' in name */
 292         if (strchr(name, '=')) {
 293                 errno = EINVAL;
 294                 return (-1);
 295         }
 296 #endif /* __DARWIN_UNIX03 */
 297
 298         if (*value == '=')                      /* no `=' in value */
 299                 ++value;
 300         /* insure __zone0 is set up before calling __malloc_check_env_name */
 301         if (init__zone0(1)) return (-1);
 302         __malloc_check_env_name(name); /* see if we are changing a malloc environment variable */
 303         return (__setenv(name, value, rewrite, 1, _NSGetEnviron(), __zone0));
 304 }
 305
 306 /*
 307  * unsetenv(name) --
 308  *      Delete environmental variable "name".
 309  */
 310 #if __DARWIN_UNIX03
 311 int
 312 #else /* !__DARWIN_UNIX03 */
 313 void
 314 #endif /* __DARWIN_UNIX03 */
 315 unsetenv(name)
 316         const char *name;
 317 {
 318 #if __DARWIN_UNIX03
 319         /* no null ptr or empty str */
 320         if(name == NULL || *name == 0) {
 321                 errno = EINVAL;
 322                 return (-1);
 323         }
 324
 325         /* no '=' in name */
 326         if (strchr(name, '=')) {
 327                 errno = EINVAL;
 328                 return (-1);
 329         }
 330         /* insure __zone0 is set up before calling __malloc_check_env_name */
 331         if (init__zone0(1)) return (-1);
 332 #else /* !__DARWIN_UNIX03 */
 333         /* no null ptr or empty str */
 334         if(name == NULL || *name == 0)
 335                 return;
 336         /* insure __zone0 is set up before calling __malloc_check_env_name */
 337         if (init__zone0(0)) return;
 338 #endif /* __DARWIN_UNIX03 */
 339         __malloc_check_env_name(name); /* see if we are changing a malloc environment variable */
 340         __unsetenv(name, *_NSGetEnviron(), __zone0);
 341 #if __DARWIN_UNIX03
 342         return 0;
 343 #endif /* __DARWIN_UNIX03 */
 344 }