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-rw-r--r--src/env/__environ.c7
-rw-r--r--src/env/__libc_start_main.c26
-rw-r--r--src/env/clearenv.c9
-rw-r--r--src/env/getenv.c14
-rw-r--r--src/env/putenv.c59
-rw-r--r--src/env/setenv.c31
-rw-r--r--src/env/unsetenv.c32
7 files changed, 178 insertions, 0 deletions
diff --git a/src/env/__environ.c b/src/env/__environ.c
new file mode 100644
index 00000000..d7bd5e50
--- /dev/null
+++ b/src/env/__environ.c
@@ -0,0 +1,7 @@
+#include "libc.h"
+
+#undef environ
+char **___environ = 0;
+weak_alias(___environ, __environ);
+weak_alias(___environ, _environ);
+weak_alias(___environ, environ);
diff --git a/src/env/__libc_start_main.c b/src/env/__libc_start_main.c
new file mode 100644
index 00000000..70af77b5
--- /dev/null
+++ b/src/env/__libc_start_main.c
@@ -0,0 +1,26 @@
+#include "libc.h"
+
+/* Any use of __environ/environ will override this symbol. */
+char **__dummy_environ = (void *)-1;
+weak_alias(__dummy_environ, ___environ);
+
+int __libc_start_main(
+ int (*main)(int, char **, char **), int argc, char **argv,
+ int (*init)(int, char **, char **), void (*fini)(void),
+ void (*ldso_fini)(void))
+{
+ /* Save the environment if it may be used by libc/application */
+ char **envp = argv+argc+1;
+ if (___environ != (void *)-1) ___environ = envp;
+
+ /* Avoid writing 0 and triggering unnecessary COW */
+ if (ldso_fini) libc.ldso_fini = ldso_fini;
+ if (fini) libc.fini = fini;
+
+ /* Execute constructors (static) linked into the application */
+ if (init) init(argc, argv, envp);
+
+ /* Pass control to to application */
+ exit(main(argc, argv, envp));
+ return 0;
+}
diff --git a/src/env/clearenv.c b/src/env/clearenv.c
new file mode 100644
index 00000000..a2475ce7
--- /dev/null
+++ b/src/env/clearenv.c
@@ -0,0 +1,9 @@
+#include <stdlib.h>
+
+extern char **__environ;
+
+int clearenv()
+{
+ __environ[0] = 0;
+ return 0;
+}
diff --git a/src/env/getenv.c b/src/env/getenv.c
new file mode 100644
index 00000000..00c1bce0
--- /dev/null
+++ b/src/env/getenv.c
@@ -0,0 +1,14 @@
+#include <stdlib.h>
+#include <string.h>
+#include "libc.h"
+
+char *getenv(const char *name)
+{
+ int i;
+ size_t l = strlen(name);
+ if (!__environ || !*name || strchr(name, '=')) return NULL;
+ for (i=0; __environ[i] && (strncmp(name, __environ[i], l)
+ || __environ[i][l] != '='); i++);
+ if (__environ[i]) return __environ[i] + l+1;
+ return NULL;
+}
diff --git a/src/env/putenv.c b/src/env/putenv.c
new file mode 100644
index 00000000..181a4181
--- /dev/null
+++ b/src/env/putenv.c
@@ -0,0 +1,59 @@
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <stdio.h>
+
+extern char **__environ;
+char **__env_map;
+
+int __putenv(char *s, int a)
+{
+ int i=0, j=0;
+ char *end = strchr(s, '=');
+ size_t l = end-s+1;
+ char **newenv = 0;
+ char **newmap = 0;
+ static char **oldenv;
+
+ if (!end || l == 1) return -1;
+ for (; __environ[i] && memcmp(s, __environ[i], l); i++);
+ if (a) {
+ if (!__env_map) {
+ __env_map = calloc(2, sizeof(char *));
+ if (__env_map) __env_map[0] = s;
+ } else {
+ for (; __env_map[j] && __env_map[j] != __environ[i]; j++);
+ if (!__env_map[j]) {
+ newmap = realloc(__env_map, sizeof(char *)*(j+2));
+ if (newmap) {
+ __env_map = newmap;
+ __env_map[j] = s;
+ __env_map[j+1] = NULL;
+ }
+ } else {
+ free(__env_map[j]);
+ }
+ }
+ }
+ if (!__environ[i]) {
+ newenv = malloc(sizeof(char *)*(i+2));
+ if (!newenv) {
+ if (a && __env_map) __env_map[j] = 0;
+ return -1;
+ }
+ memcpy(newenv, __environ, sizeof(char *)*i);
+ newenv[i] = s;
+ newenv[i+1] = 0;
+ __environ = newenv;
+ free(oldenv);
+ oldenv = __environ;
+ }
+
+ __environ[i] = s;
+ return 0;
+}
+
+int putenv(char *s)
+{
+ return __putenv(s, 0);
+}
diff --git a/src/env/setenv.c b/src/env/setenv.c
new file mode 100644
index 00000000..03e165c8
--- /dev/null
+++ b/src/env/setenv.c
@@ -0,0 +1,31 @@
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+int __putenv(char *s, int a);
+
+int setenv(const char *var, const char *value, int overwrite)
+{
+ char *s;
+ int l1, l2;
+
+ if (strchr(var, '=')) {
+ errno = EINVAL;
+ return -1;
+ }
+ if (!overwrite && getenv(var)) return 0;
+
+ l1 = strlen(var);
+ l2 = strlen(value);
+ s = malloc(l1+l2+2);
+ memcpy(s, var, l1);
+ s[l1] = '=';
+ memcpy(s+l1+1, value, l2);
+ s[l1+l2+1] = 0;
+ if (__putenv(s, 1)) {
+ free(s);
+ errno = ENOMEM;
+ return -1;
+ }
+ return 0;
+}
diff --git a/src/env/unsetenv.c b/src/env/unsetenv.c
new file mode 100644
index 00000000..7493d970
--- /dev/null
+++ b/src/env/unsetenv.c
@@ -0,0 +1,32 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+extern char **__environ;
+extern char **__env_map;
+
+int unsetenv(const char *name)
+{
+ int i, j;
+ size_t l = strlen(name);
+
+ if (!*name || strchr(name, '=')) {
+ errno = EINVAL;
+ return -1;
+ }
+again:
+ for (i=0; __environ[i] && (memcmp(name, __environ[i], l) || __environ[i][l] != '='); i++);
+ if (__environ[i]) {
+ if (__env_map) {
+ for (j=0; __env_map[j] && __env_map[j] != __environ[i]; j++);
+ free (__env_map[j]);
+ for (; __env_map[j]; j++)
+ __env_map[j] = __env_map[j+1];
+ }
+ for (; __environ[i]; i++)
+ __environ[i] = __environ[i+1];
+ goto again;
+ }
+ return 0;
+}