summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--stdlib/getenv.c64
1 files changed, 5 insertions, 59 deletions
diff --git a/stdlib/getenv.c b/stdlib/getenv.c
index e3157ce2f3..8408e641a6 100644
--- a/stdlib/getenv.c
+++ b/stdlib/getenv.c
@@ -15,76 +15,22 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <endian.h>
-#include <errno.h>
-#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
-
-/* Return the value of the environment variable NAME. This implementation
- is tuned a bit in that it assumes no environment variable has an empty
- name which of course should always be true. We have a special case for
- one character names so that for the general case we can assume at least
- two characters which we can access. By doing this we can avoid using the
- `strncmp' most of the time. */
char *
getenv (const char *name)
{
- char **ep;
- uint16_t name_start;
-
if (__environ == NULL || name[0] == '\0')
return NULL;
- if (name[1] == '\0')
- {
- /* The name of the variable consists of only one character. Therefore
- the first two characters of the environment entry are this character
- and a '=' character. */
-#if __BYTE_ORDER == __LITTLE_ENDIAN || !_STRING_ARCH_unaligned
- name_start = ('=' << 8) | *(const unsigned char *) name;
-#else
- name_start = '=' | ((*(const unsigned char *) name) << 8);
-#endif
- for (ep = __environ; *ep != NULL; ++ep)
- {
-#if _STRING_ARCH_unaligned
- uint16_t ep_start = *(uint16_t *) *ep;
-#else
- uint16_t ep_start = (((unsigned char *) *ep)[0]
- | (((unsigned char *) *ep)[1] << 8));
-#endif
- if (name_start == ep_start)
- return &(*ep)[2];
- }
- }
- else
+ size_t len = strlen (name);
+ for (char **ep = __environ; *ep != NULL; ++ep)
{
- size_t len = strlen (name);
-#if _STRING_ARCH_unaligned
- name_start = *(const uint16_t *) name;
-#else
- name_start = (((const unsigned char *) name)[0]
- | (((const unsigned char *) name)[1] << 8));
-#endif
- len -= 2;
- name += 2;
-
- for (ep = __environ; *ep != NULL; ++ep)
- {
-#if _STRING_ARCH_unaligned
- uint16_t ep_start = *(uint16_t *) *ep;
-#else
- uint16_t ep_start = (((unsigned char *) *ep)[0]
- | (((unsigned char *) *ep)[1] << 8));
-#endif
-
- if (name_start == ep_start && !strncmp (*ep + 2, name, len)
- && (*ep)[len + 2] == '=')
- return &(*ep)[len + 3];
- }
+ if (name[0] == (*ep)[0]
+ && strncmp (name, *ep, len) == 0 && (*ep)[len] == '=')
+ return *ep + len + 1;
}
return NULL;