+/* UID/GID functions */
+
+int lc_getuid(lua_State* L)
+{
+ lua_pushinteger(L, getuid());
+ return 1;
+}
+
+int lc_getgid(lua_State* L)
+{
+ lua_pushinteger(L, getgid());
+ return 1;
+}
+
+int lc_setuid(lua_State* L)
+{
+ int uid = -1;
+ if(lua_gettop(L) < 1)
+ return 0;
+ if(!lua_isnumber(L, 1) && lua_tostring(L, 1))
+ {
+ /* Passed UID is actually a string, so look up the UID */
+ struct passwd *p;
+ p = getpwnam(lua_tostring(L, 1));
+ if(!p)
+ {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "no-such-user");
+ return 2;
+ }
+ uid = p->pw_uid;
+ }
+ else
+ {
+ uid = lua_tonumber(L, 1);
+ }
+
+ if(uid>-1)
+ {
+ /* Ok, attempt setuid */
+ errno = 0;
+ if(setuid(uid))
+ {
+ /* Fail */
+ lua_pushboolean(L, 0);
+ switch(errno)
+ {
+ case EINVAL:
+ lua_pushstring(L, "invalid-uid");
+ break;
+ case EPERM:
+ lua_pushstring(L, "permission-denied");
+ break;
+ default:
+ lua_pushstring(L, "unknown-error");
+ }
+ return 2;
+ }
+ else
+ {
+ /* Success! */
+ lua_pushboolean(L, 1);
+ return 1;
+ }
+ }
+
+ /* Seems we couldn't find a valid UID to switch to */
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "invalid-uid");
+ return 2;
+}
+
+/* Like POSIX's setrlimit()/getrlimit() API functions.
+ *
+ * Syntax:
+ * pposix.setrlimit( resource, soft limit, hard limit)
+ *
+ * Any negative limit will be replace with the current limit by an additional call of getrlimit().
+ *
+ * Example usage:
+ * pposix.setrlimit("NOFILE", 1000, 2000)
+ */
+int string2resource(const char *s) {
+ if (!strcmp(resource, "CORE")) return RLIMIT_CORE;
+ if (!strcmp(resource, "CPU")) return RLIMIT_CPU;
+ if (!strcmp(resource, "DATA")) return RLIMIT_DATA;
+ if (!strcmp(resource, "FSIZE")) return RLIMIT_FSIZE;
+ if (!strcmp(resource, "MEMLOCK")) return RLIMIT_MEMLOCK;
+ if (!strcmp(resource, "NOFILE")) return RLIMIT_NOFILE;
+ if (!strcmp(resource, "NPROC")) return RLIMIT_NPROC;
+ if (!strcmp(resource, "RSS")) return RLIMIT_RSS;
+ if (!strcmp(resource, "STACK")) return RLIMIT_STACK;
+ return -1;
+}
+
+int lc_setrlimit(lua_State *L) {
+ int arguments = lua_gettop(L);
+ int softlimit = -1;
+ int hardlimit = -1;
+ const char *resource = NULL;
+ int rid = -1;
+ if(arguments < 1 || arguments > 3) {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "Wrong number of arguments");
+ }
+
+ resource = luaL_checkstring(L, 1);
+ softlimit = luaL_checkinteger(L, 2);
+ hardlimit = luaL_checkinteger(L, 3);
+
+ rid = string2resource(resource);
+ if (rid != -1) {
+ rlimit lim;
+ rlimit lim_current;
+
+ if (softlimit < 0 || hardlimit < 0) {
+ if (getrlimit(rid, &lim_current)) {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "getrlimit() failed.");
+ return 2;
+ }
+ }
+
+ if (softimit < 0) lim.rlim_cur = lim_current.rlim_cur;
+ else lim.rlim_cur = softlimit;
+ if (hardlimit < 0) lim.rlim_max = lim_current.rlim_max;
+ else lim.rlim_max = hardlimit;
+
+ if (setrlimit(rid, &lim)) {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "setrlimit() failed.");
+ return 2;
+ }
+ } else {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "Unsupported resoucrce. Sorry I'm pretty limited by POSIX standard.");
+ return 2;
+ }
+ lua_pushboolean(L, 1);
+ return 1;
+}
+
+int lc_getrlimit(lua_State *L) {
+ int arguments = lua_gettop(L);
+ const char *resource = NULL;
+ int rid = -1;
+ rlimit lim;
+
+ if (arguments != 1) {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "I expect one argument only, the resource string.");
+ return 2;
+ }
+
+ resource = luaL_checkstring(L, 1);
+ rid = string2resource(resource);
+ if (rid != -1) {
+ if (getrlimit(rid, &lim)) {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "getrlimit() failed.");
+ return 2;
+ }
+ } else {
+ lua_pushboolean(L, 0);
+ lua_pushstring(L, "Unsupported resoucrce. Sorry I'm pretty limited by POSIX standard.");
+ return 2;
+ }
+ lua_pushboolean(L, 1);
+ lua_pushnumber(L, lim.rlim_cur);
+ lua_pushnumber(L, lim.rlim_max);
+ return 3;
+}
+