elua: utility func to exec a process (without spawning a shell like os.execute)

src/bin/elua/main.c

@@ -1,6 +1,11 @@
 /* The Lua runtime component of the EFL */
 
 #include <getopt.h>
+#ifndef _WIN32
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#endif
 
 #include "main.h"
 
@@ -192,6 +197,81 @@ static int register_callbacks(lua_State *L) {
     return 1;
 }
 
+static int elua_exec(lua_State *L) {
+#ifndef _WIN32
+    pid_t cpid = fork();
+    if (cpid < 0) {
+        lua_pushnil(L);
+        lua_pushstring(L, strerror(errno));
+        return 2;
+    }
+    if (!cpid) {
+        const char **argv = alloca((lua_gettop(L) + 1) * sizeof(char*));
+        int  i;
+        for (i = 0; i < lua_gettop(L); ++i) {
+            argv[i] = lua_tostring(L, i + 1);
+        }
+        argv[lua_gettop(L)] = NULL;
+        execv(argv[0], (char*const*)argv);
+        exit(1);
+    } else {
+        int status;
+        if (waitpid(cpid, &status, 0) < 0) {
+            lua_pushnil(L);
+            lua_pushstring(L, strerror(errno));
+            return 2;
+        }
+        lua_pushinteger(L, status);
+        return 1;
+    }
+#else
+    char buf[4096]; /* temporary, only because Windows API is retarded */
+    char *cptr = buf;
+
+    STARTUPINFO si;
+    PROCESS_INFORMATION pi;
+    ZeroMemory(&si, sizeof(si));
+    si.cb = sizeof(si);
+    ZeroMemory(&si, sizeof(pi));
+
+    int  i;
+    for (i = 1; i < lua_gettop(L); ++i) {
+        size_t l;
+        const char *arg = lua_tolstring(L, i + 1, &l);
+        *(cptr++) = '"';
+        memcpy(cptr, l + 1, arg);
+        cptr += l;
+        *(cptr++) = '"'
+        if (i != (lua_gettop(L) - 1)) {
+            *(cptr++) = ' ';
+        } else {
+            cptr[0] = '\0';
+        }
+    }
+
+    if (!CreateProcess(lua_tostring(L, 1), buf, NULL, NULL, FALSE, 0, NULL,
+    NULL, &si, &pi)) {
+        LPVOID msgbuf;
+        DWORD dw = GetLastError();
+        FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER
+            | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+            NUL, dw, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&msgbuf,
+            0, NULL);
+        lua_pushnil(L);
+        lua_pushstring(L, (const char*)msgbuf);
+        LocalFree(msgbuf);
+        return 2;
+    }
+
+    int status;
+    if (!GetExitCodeProcess(pi.hProcess, &status)) status = 0;
+    CloseHandle(pi.hProcess);
+    CloseHandle(pi.hThread);
+    lua_pushinteger(L, status);
+    return 1;
+#endif
+}
+
 struct Main_Data {
     int    argc;
     char **argv;
@@ -201,6 +281,7 @@ struct Main_Data {
 const luaL_reg cutillib[] = {
     { "init_module", init_module },
     { "register_callbacks", register_callbacks },
+    { "exec", elua_exec },
     { NULL, NULL }
 };
 

src/bin/elua/xgettext.lua

@@ -2,6 +2,7 @@
 -- provides a drop-in replacement of xgettext that supports Lua (but not any
 -- other language)
 
+local cutil  = require("cutil")
 local getopt = require("getopt")
 
 local VERSION = "1.0.0"
@@ -164,16 +165,16 @@ end
 
 local hasxgettext = os.getenv("XGETTEXT")
 if hasxgettext then
-    local gargs = { "\"" .. hasxgettext .. "\"" }
+    local gargs = { hasxgettext }
     for i = 1, #opts do
-        gargs[#gargs + 1] = "\"" .. arg[i] .. "\""
+        gargs[#gargs + 1] = arg[i]
     end
     for i, v in ipairs(args) do
         if not v:match("^.+%.lua$") then
             gargs[#gargs + 1] = v
         end
     end
-    os.execute(table.concat(gargs, " "))
+    cutil.exec(unpack(gargs))
 end
 
 return true