-/* Copyright (C) 1992,1995-2001,2004, 2008 Free Software Foundation, Inc.
+/* Copyright (C) 1992-2019 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
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, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
+ License along with the GNU C Library; if not, see
+ <https://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
#if _LIBC
/* This lock protects against simultaneous modifications of `environ'. */
-# include <bits/libc-lock.h>
+# include <libc-lock.h>
__libc_lock_define_initialized (static, envlock)
# define LOCK __libc_lock_lock (envlock)
# define UNLOCK __libc_lock_unlock (envlock)
to reuse values once generated for a `setenv' call since we can never
free the strings. */
int
-__add_to_environ (name, value, combined, replace)
- const char *name;
- const char *value;
- const char *combined;
- int replace;
+__add_to_environ (const char *name, const char *value, const char *combined,
+ int replace)
{
- register char **ep;
- register size_t size;
+ 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);
- const size_t vallen = value != NULL ? strlen (value) + 1 : 0;
+ size_t vallen;
+ if (combined == NULL)
+ vallen = strlen (value) + 1;
LOCK;
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
-# ifdef __GNUC__
- char new_value[namelen + 1 + vallen];
-# else
- char *new_value = (char *) alloca (namelen + 1 + vallen);
-# endif
-# 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 (__builtin_expect (new_environ[size] == NULL, 1))
-#endif
- {
- new_environ[size] = (char *) malloc (namelen + 1 + vallen);
- if (__builtin_expect (new_environ[size] == NULL, 0))
- {
- __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]);
- }
- }
-
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;
}
- else if (replace)
+ if (*ep == NULL || replace)
{
char *np;
np = (char *) combined;
else
{
+ const size_t varlen = namelen + 1 + vallen;
#ifdef USE_TSEARCH
-# ifdef __GNUC__
- char new_value[namelen + 1 + vallen];
-# else
- char *new_value = (char *) alloca (namelen + 1 + vallen);
-# endif
+ 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);
# endif
np = KNOWN_VALUE (new_value);
- if (__builtin_expect (np == NULL, 1))
+ if (__glibc_likely (np == NULL))
#endif
{
- np = malloc (namelen + 1 + vallen);
- if (__builtin_expect (np == NULL, 0))
+#ifdef USE_TSEARCH
+ if (__glibc_unlikely (! use_alloca))
+ np = new_value;
+ else
+#endif
{
- UNLOCK;
- return -1;
- }
+ np = malloc (varlen);
+ if (__glibc_unlikely (np == NULL))
+ {
+ UNLOCK;
+ return -1;
+ }
#ifdef USE_TSEARCH
- memcpy (np, new_value, namelen + 1 + vallen);
+ memcpy (np, new_value, varlen);
#else
- memcpy (np, name, namelen);
- np[namelen] = '=';
- memcpy (&np[namelen + 1], value, vallen);
+ 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;
}
int
-setenv (name, value, replace)
- const char *name;
- const char *value;
- int replace;
+setenv (const char *name, const char *value, int replace)
{
if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
{
}
int
-unsetenv (name)
- const char *name;
+unsetenv (const char *name)
{
size_t len;
char **ep;
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;
+ {
+ 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;
never made it. Nevertheless the POSIX.9 standard (POSIX bindings
for Fortran 77) requires this function. */
int
-clearenv ()
+clearenv (void)
{
LOCK;
projects / thirdparty / glibc.git / blobdiff