From 0b44a0315b47dd8eced9f3b7f31580cf14bbfc01 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 12 Feb 2011 00:22:29 -0500 Subject: initial check-in, version 0.5.0 --- src/env/__environ.c | 7 ++++++ src/env/__libc_start_main.c | 26 ++++++++++++++++++++ src/env/clearenv.c | 9 +++++++ src/env/getenv.c | 14 +++++++++++ src/env/putenv.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ src/env/setenv.c | 31 ++++++++++++++++++++++++ src/env/unsetenv.c | 32 ++++++++++++++++++++++++ 7 files changed, 178 insertions(+) create mode 100644 src/env/__environ.c create mode 100644 src/env/__libc_start_main.c create mode 100644 src/env/clearenv.c create mode 100644 src/env/getenv.c create mode 100644 src/env/putenv.c create mode 100644 src/env/setenv.c create mode 100644 src/env/unsetenv.c (limited to 'src/env') 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 + +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 +#include +#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 +#include +#include +#include + +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 +#include +#include + +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 +#include +#include +#include + +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; +} -- cgit v1.2.1