diff options
Diffstat (limited to 'stdlib/setenv.c')
-rw-r--r-- | stdlib/setenv.c | 340 |
1 files changed, 0 insertions, 340 deletions
diff --git a/stdlib/setenv.c b/stdlib/setenv.c deleted file mode 100644 index f3c0220045..0000000000 --- a/stdlib/setenv.c +++ /dev/null @@ -1,340 +0,0 @@ -/* Copyright (C) 1992-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#if HAVE_CONFIG_H -# include <config.h> -#endif - -/* Pacify GCC; see the commentary about VALLEN below. This is needed - at least through GCC 4.9.2. Pacify GCC for the entire file, as - there seems to be no way to pacify GCC selectively, only for the - place where it's needed. Do not use DIAG_IGNORE_NEEDS_COMMENT - here, as it's not defined yet. */ -#pragma GCC diagnostic ignored "-Wmaybe-uninitialized" - -#include <errno.h> -#if !_LIBC -# if !defined errno && !defined HAVE_ERRNO_DECL -extern int errno; -# endif -# define __set_errno(ev) ((errno) = (ev)) -#endif - -#if _LIBC || HAVE_STDLIB_H -# include <stdlib.h> -#endif -#if _LIBC || HAVE_STRING_H -# include <string.h> -#endif -#if _LIBC || HAVE_UNISTD_H -# include <unistd.h> -#endif - -#if !_LIBC -# define __environ environ -# ifndef HAVE_ENVIRON_DECL -extern char **environ; -# endif -#endif - -#if _LIBC -/* This lock protects against simultaneous modifications of `environ'. */ -# include <libc-lock.h> -__libc_lock_define_initialized (static, envlock) -# define LOCK __libc_lock_lock (envlock) -# define UNLOCK __libc_lock_unlock (envlock) -#else -# define LOCK -# define UNLOCK -#endif - -/* In the GNU C library we must keep the namespace clean. */ -#ifdef _LIBC -# define setenv __setenv -# define unsetenv __unsetenv -# define clearenv __clearenv -# define tfind __tfind -# define tsearch __tsearch -#endif - -/* In the GNU C library implementation we try to be more clever and - allow arbitrarily many changes of the environment given that the used - values are from a small set. Outside glibc this will eat up all - memory after a while. */ -#if defined _LIBC || (defined HAVE_SEARCH_H && defined HAVE_TSEARCH \ - && defined __GNUC__) -# define USE_TSEARCH 1 -# include <search.h> - -/* This is a pointer to the root of the search tree with the known - values. */ -static void *known_values; - -# define KNOWN_VALUE(Str) \ - ({ \ - void *value = tfind (Str, &known_values, (__compar_fn_t) strcmp); \ - value != NULL ? *(char **) value : NULL; \ - }) -# define STORE_VALUE(Str) \ - tsearch (Str, &known_values, (__compar_fn_t) strcmp) - -#else -# undef USE_TSEARCH - -# define KNOWN_VALUE(Str) NULL -# define STORE_VALUE(Str) do { } while (0) - -#endif - - -/* If this variable is not a null pointer we allocated the current - environment. */ -static char **last_environ; - - -/* This function is used by `setenv' and `putenv'. The difference between - the two functions is that for the former must create a new string which - is then placed in the environment, while the argument of `putenv' - must be used directly. This is all complicated by the fact that we try - to reuse values once generated for a `setenv' call since we can never - free the strings. */ -int -__add_to_environ (const char *name, const char *value, const char *combined, - int replace) -{ - char **ep; - size_t size; - - /* Compute lengths before locking, so that the critical section is - less of a performance bottleneck. VALLEN is needed only if - COMBINED is null (unfortunately GCC is not smart enough to deduce - this; see the #pragma at the start of this file). Testing - COMBINED instead of VALUE causes setenv (..., NULL, ...) to dump - core now instead of corrupting memory later. */ - const size_t namelen = strlen (name); - size_t vallen; - if (combined == NULL) - vallen = strlen (value) + 1; - - LOCK; - - /* We have to get the pointer now that we have the lock and not earlier - since another thread might have created a new environment. */ - ep = __environ; - - size = 0; - if (ep != NULL) - { - for (; *ep != NULL; ++ep) - if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=') - break; - else - ++size; - } - - if (ep == NULL || __builtin_expect (*ep == NULL, 1)) - { - char **new_environ; - - /* We allocated this space; we can extend it. */ - new_environ = (char **) realloc (last_environ, - (size + 2) * sizeof (char *)); - if (new_environ == NULL) - { - UNLOCK; - return -1; - } - - if (__environ != last_environ) - memcpy ((char *) new_environ, (char *) __environ, - size * sizeof (char *)); - - new_environ[size] = NULL; - new_environ[size + 1] = NULL; - ep = new_environ + size; - - last_environ = __environ = new_environ; - } - if (*ep == NULL || replace) - { - char *np; - - /* Use the user string if given. */ - if (combined != NULL) - np = (char *) combined; - else - { - const size_t varlen = namelen + 1 + vallen; -#ifdef USE_TSEARCH - char *new_value; - int use_alloca = __libc_use_alloca (varlen); - if (__builtin_expect (use_alloca, 1)) - new_value = (char *) alloca (varlen); - else - { - new_value = malloc (varlen); - if (new_value == NULL) - { - UNLOCK; - return -1; - } - } -# ifdef _LIBC - __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1), - value, vallen); -# else - memcpy (new_value, name, namelen); - new_value[namelen] = '='; - memcpy (&new_value[namelen + 1], value, vallen); -# endif - - np = KNOWN_VALUE (new_value); - if (__glibc_likely (np == NULL)) -#endif - { -#ifdef USE_TSEARCH - if (__glibc_unlikely (! use_alloca)) - np = new_value; - else -#endif - { - np = malloc (varlen); - if (__glibc_unlikely (np == NULL)) - { - UNLOCK; - return -1; - } - -#ifdef USE_TSEARCH - memcpy (np, new_value, varlen); -#else - memcpy (np, name, namelen); - np[namelen] = '='; - memcpy (&np[namelen + 1], value, vallen); -#endif - } - /* And remember the value. */ - STORE_VALUE (np); - } -#ifdef USE_TSEARCH - else - { - if (__glibc_unlikely (! use_alloca)) - free (new_value); - } -#endif - } - - *ep = np; - } - - UNLOCK; - - return 0; -} - -int -setenv (const char *name, const char *value, int replace) -{ - if (name == NULL || *name == '\0' || strchr (name, '=') != NULL) - { - __set_errno (EINVAL); - return -1; - } - - return __add_to_environ (name, value, NULL, replace); -} - -int -unsetenv (const char *name) -{ - size_t len; - char **ep; - - if (name == NULL || *name == '\0' || strchr (name, '=') != NULL) - { - __set_errno (EINVAL); - return -1; - } - - len = strlen (name); - - LOCK; - - ep = __environ; - if (ep != NULL) - while (*ep != NULL) - { - if (!strncmp (*ep, name, len) && (*ep)[len] == '=') - { - /* Found it. Remove this pointer by moving later ones back. */ - char **dp = ep; - - do - dp[0] = dp[1]; - while (*dp++); - /* Continue the loop in case NAME appears again. */ - } - else - ++ep; - } - - UNLOCK; - - return 0; -} - -/* The `clearenv' was planned to be added to POSIX.1 but probably - never made it. Nevertheless the POSIX.9 standard (POSIX bindings - for Fortran 77) requires this function. */ -int -clearenv (void) -{ - LOCK; - - if (__environ == last_environ && __environ != NULL) - { - /* We allocated this environment so we can free it. */ - free (__environ); - last_environ = NULL; - } - - /* Clear the environment pointer removes the whole environment. */ - __environ = NULL; - - UNLOCK; - - return 0; -} -#ifdef _LIBC -libc_freeres_fn (free_mem) -{ - /* Remove all traces. */ - clearenv (); - - /* Now remove the search tree. */ - __tdestroy (known_values, free); - known_values = NULL; -} - -# undef setenv -# undef unsetenv -# undef clearenv -weak_alias (__setenv, setenv) -weak_alias (__unsetenv, unsetenv) -weak_alias (__clearenv, clearenv) -#endif |