-/* Copyright (C) 1992, 1995, 2000 Free Software Foundation, Inc.
+/* Copyright (C) 1992,1995-1999,2000-2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
-NOTE: The canonical source of this file is maintained with the GNU C Library.
-Bugs can be reported to bug-glibc@prep.ai.mit.edu.
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
-This program is free software; you can redistribute it and/or modify it
-under the terms of the GNU General Public License as published by the
-Free Software Foundation; either version 2, 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
+ Library General Public License for more details.
-This program 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 General Public License for more details.
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
-USA. */
-
-#ifdef HAVE_CONFIG_H
+#if HAVE_CONFIG_H
# include <config.h>
#endif
+#ifdef __GNUC__
+# ifndef alloca
+# define alloca __builtin_alloca
+# endif
+#else
+# ifdef _MSC_VER
+# include <malloc.h>
+# define alloca _alloca
+# else
+# if HAVE_ALLOCA_H
+# include <alloca.h>
+# else
+# ifdef _AIX
+ #pragma alloca
+# else
+# ifdef __hpux /* This section must match that of bison generated files. */
+# ifdef __cplusplus
+extern "C" void *alloca (unsigned int);
+# else /* not __cplusplus */
+void *alloca ();
+# endif /* not __cplusplus */
+# else /* not __hpux */
+# ifndef alloca
+char *alloca ();
+# endif
+# endif /* __hpux */
+# endif
+# endif
+# endif
+#endif
+
#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>
# include <unistd.h>
#endif
-#ifndef HAVE_GNU_LD
+/* For those losing systems which don't have 'alloca' we have to add
+ some additional code emulating it. */
+#if _LIBC || HAVE_ALLOCA
+# define freea(p) /* nothing */
+#else
+# define alloca(n) malloc (n)
+# define freea(p) free (p)
+#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 <bits/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 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>
+typedef int (*compar_fn_t) (const void *, const void *);
+
+/* 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
-setenv (name, value, replace)
- const char *name;
- const char *value;
- int replace;
+__add_to_environ (const char *name, const char *value, const char *combined,
+ int replace)
{
register char **ep;
register size_t size;
const size_t namelen = strlen (name);
- const size_t vallen = strlen (value) + 1;
+ const size_t vallen = value != NULL ? strlen (value) + 1 : 0;
+
+ 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;
- for (ep = __environ; *ep != NULL; ++ep)
- if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
- break;
- else
- ++size;
+ if (ep != NULL)
+ {
+ for (; *ep != NULL; ++ep)
+ if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
+ break;
+ else
+ ++size;
+ }
- if (*ep == NULL)
+ if (ep == NULL || *ep == NULL)
{
- static char **last_environ;
char **new_environ;
- if (__environ == last_environ)
- /* We allocated this space; we can extend it. */
- new_environ = (char **) realloc (last_environ,
- (size + 2) * sizeof (char *));
- else
- new_environ = (char **) malloc ((size + 2) * sizeof (char *));
+#ifdef USE_TSEARCH
+ char *new_value;
+#endif
+ /* We allocated this space; we can extend it. */
+ new_environ =
+ (char **) (last_environ == NULL
+ ? malloc ((size + 2) * sizeof (char *))
+ : realloc (last_environ, (size + 2) * sizeof (char *)));
if (new_environ == NULL)
- return -1;
-
- new_environ[size] = malloc (namelen + 1 + vallen);
- if (new_environ[size] == NULL)
{
- free ((char *) new_environ);
- errno = ENOMEM;
+ UNLOCK;
return -1;
}
+ /* If the whole entry is given add it. */
+ if (combined != NULL)
+ /* We must not add the string to the search tree since it belongs
+ to the user. */
+ new_environ[size] = (char *) combined;
+ else
+ {
+ /* See whether the value is already known. */
+#ifdef USE_TSEARCH
+ new_value = (char *) alloca (namelen + 1 + vallen);
+# 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
+
+ new_environ[size] = KNOWN_VALUE (new_value);
+ if (new_environ[size] == NULL)
+#endif
+ {
+ new_environ[size] = (char *) malloc (namelen + 1 + vallen);
+ if (new_environ[size] == NULL)
+ {
+#ifdef USE_TSEARCH
+ freea (new_value);
+#endif
+ __set_errno (ENOMEM);
+ UNLOCK;
+ return -1;
+ }
+
+#ifdef USE_TSEARCH
+ memcpy (new_environ[size], new_value, namelen + 1 + vallen);
+#else
+ memcpy (new_environ[size], name, namelen);
+ new_environ[size][namelen] = '=';
+ memcpy (&new_environ[size][namelen + 1], value, vallen);
+#endif
+ /* And save the value now. We cannot do this when we remove
+ the string since then we cannot decide whether it is a
+ user string or not. */
+ STORE_VALUE (new_environ[size]);
+ }
+#ifdef USE_TSEARCH
+ freea (new_value);
+#endif
+ }
+
if (__environ != last_environ)
memcpy ((char *) new_environ, (char *) __environ,
size * sizeof (char *));
- memcpy (new_environ[size], name, namelen);
- new_environ[size][namelen] = '=';
- memcpy (&new_environ[size][namelen + 1], value, vallen);
-
new_environ[size + 1] = NULL;
last_environ = __environ = new_environ;
}
else if (replace)
{
- size_t len = strlen (*ep);
- if (len + 1 < namelen + 1 + vallen)
+ char *np;
+
+ /* Use the user string if given. */
+ if (combined != NULL)
+ np = (char *) combined;
+ else
{
- /* The existing string is too short; malloc a new one. */
- char *new = malloc (namelen + 1 + vallen);
- if (new == NULL)
- return -1;
- *ep = new;
+#ifdef USE_TSEARCH
+ char *new_value = alloca (namelen + 1 + vallen);
+# 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 (np == NULL)
+#endif
+ {
+ np = malloc (namelen + 1 + vallen);
+ if (np == NULL)
+ {
+#ifdef USE_TSEARCH
+ freea (new_value);
+#endif
+ UNLOCK;
+ return -1;
+ }
+
+#ifdef USE_TSEARCH
+ memcpy (np, new_value, namelen + 1 + vallen);
+#else
+ memcpy (np, name, namelen);
+ np[namelen] = '=';
+ memcpy (&np[namelen + 1], value, vallen);
+#endif
+ /* And remember the value. */
+ STORE_VALUE (np);
+ }
+#ifdef USE_TSEARCH
+ freea (new_value);
+#endif
}
- memcpy (*ep, name, namelen);
- (*ep)[namelen] = '=';
- memcpy (&(*ep)[namelen + 1], value, vallen);
+
+ *ep = np;
}
+ UNLOCK;
+
return 0;
}
-void
-unsetenv (name)
- const char *name;
+int
+setenv (const char *name, const char *value, int replace)
{
- const size_t len = strlen (name);
- char **ep;
-
- for (ep = __environ; *ep; ++ep)
- 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. */
- }
+ return __add_to_environ (name, value, NULL, replace);
}
+
+/* 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 ()
+{
+ 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
+static void
+free_mem (void)
+{
+ /* Remove all traces. */
+ clearenv ();
+
+ /* Now remove the search tree. */
+ __tdestroy (known_values, free);
+ known_values = NULL;
+}
+text_set_element (__libc_subfreeres, free_mem);
+
+
+# undef setenv
+# undef clearenv
+weak_alias (__setenv, setenv)
+weak_alias (__clearenv, clearenv)
+#endif
--- /dev/null
+/* Copyright (C) 1992,1995-1999,2000-2002 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 Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#if HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#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 <bits/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 unsetenv __unsetenv
+#endif
+
+
+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;
+ 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;
+}
+
+#ifdef _LIBC
+# undef unsetenv
+weak_alias (__unsetenv, unsetenv)
+#endif
projects / gnulib.git / commitdiff