Libc-1158.50.2.tar.gz

[apple/libc.git] / stdlib / FreeBSD / getenv.c

diff --git a/stdlib/FreeBSD/getenv.c b/stdlib/FreeBSD/getenv.c
index aa159892652406935dd6801eb2c71d2ff2fb26a0..bde7421158357a1012895caa2aff28dcfe2054ca 100644 (file)
--- a/stdlib/FreeBSD/getenv.c
+++ b/stdlib/FreeBSD/getenv.c
@@ -10,10 +10,6 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *     This product includes software developed by the University of
- *     California, Berkeley and its contributors.
  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
@@ -35,16 +31,20 @@
 static char sccsid[] = "@(#)getenv.c   8.1 (Berkeley) 6/4/93";
 #endif /* LIBC_SCCS and not lint */
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/stdlib/getenv.c,v 1.4 2002/03/21 22:48:41 obrien Exp $");
+__FBSDID("$FreeBSD: src/lib/libc/stdlib/getenv.c,v 1.8 2007/05/01 16:02:41 ache Exp $");
 
+#include <os/lock_private.h>
 #include <stdlib.h>
 #include <stddef.h>
 #include <string.h>
+#include <crt_externs.h>
 
-inline char *__findenv(const char *, int *);
+__private_extern__ char *__findenv_locked(const char *, int *, char **);
+__private_extern__ void __environ_lock(void);
+__private_extern__ void __environ_unlock(void);
 
 /*
- * __findenv --
+ * __findenv_locked --
  *     Returns pointer to value associated with name, if any, else NULL.
  *     Sets offset to be the offset of the name/value combination in the
  *     environmental array, for use by setenv(3) and unsetenv(3).
@@ -52,12 +52,12 @@ inline char *__findenv(const char *, int *);
  *
  *     This routine *should* be a static; don't use it.
  */
-inline char *
-__findenv(name, offset)
+__private_extern__ char *
+__findenv_locked(name, offset, environ)
        const char *name;
        int *offset;
+       char **environ;
 {
-       extern char **environ;
        int len, i;
        const char *np;
        char **p, *cp;
@@ -79,6 +79,48 @@ __findenv(name, offset)
        return (NULL);
 }
 
+static os_unfair_lock __environ_lock_obj = OS_UNFAIR_LOCK_INIT;
+__private_extern__ void
+__environ_lock(void)
+{
+#if TARGET_OS_IOS && !TARGET_OS_SIMULATOR
+       os_unfair_lock_lock_with_options_4Libc(
+                       &__environ_lock_obj, OS_UNFAIR_LOCK_DATA_SYNCHRONIZATION);
+#else // TARGET_OS_IOS && !TARGET_OS_SIMULATOR
+       os_unfair_lock_lock(&__environ_lock_obj);
+#endif // TARGET_OS_IOS && !TARGET_OS_SIMULATOR
+}
+__private_extern__ void
+__environ_unlock(void)
+{
+#if TARGET_OS_IOS && !TARGET_OS_SIMULATOR
+       os_unfair_lock_unlock_4Libc(&__environ_lock_obj);
+#else // TARGET_OS_IOS && !TARGET_OS_SIMULATOR
+       os_unfair_lock_unlock(&__environ_lock_obj);
+#endif // TARGET_OS_IOS && !TARGET_OS_SIMULATOR
+}
+__private_extern__ void
+__environ_lock_fork_child(void)
+{
+       __environ_lock_obj = OS_UNFAIR_LOCK_INIT;
+}
+
+/*
+ * _getenvp -- SPI using an arbitrary pointer to string array (the array must
+ * have been created with malloc) and an env state, created by _allocenvstate().
+ *     Returns ptr to value associated with name, if any, else NULL.
+ */
+char *
+_getenvp(const char *name, char ***envp, void *state __unused)
+{
+       // envp is passed as an argument, so the lock is not protecting everything
+       int offset;
+       __environ_lock();
+       char *result = (__findenv_locked(name, &offset, *envp));
+       __environ_unlock();
+       return result;
+}
+
 /*
  * getenv --
  *     Returns ptr to value associated with name, if any, else NULL.
@@ -88,6 +130,8 @@ getenv(name)
        const char *name;
 {
        int offset;
-
-       return (__findenv(name, &offset));
+       __environ_lock();
+       char *result = __findenv_locked(name, &offset, *_NSGetEnviron());
+       __environ_unlock();
+       return result;
 }