Re: [Monotone-devel] [PATCH] New lua command execute_redirout which executes an os command and captures standard output

[Alex Queiroz]

Hallo,

On 8/14/06, Daniel Dickinson <address@hidden> wrote:
============================================================
> - --- luaext_platform.cc        d6b2a9e14b19d3fe6bc6105f3574048a333b118b
> +++ luaext_platform.cc  186f18019b766de62254ea6e1a53dd82c08ac00b
> @@ -1,7 +1,8 @@
>
>  #include "lua.hh"
>
>  #include <signal.h>
> +#include <string>
>
>  #include "platform.hh"
>
> @@ -74,6 +75,28 @@ LUAEXT(spawn_redirected, )
>    return 1;
>  }
>
> +LUAEXT(execute_redirout, )
> +{
> +  std::string out;
> +  int n = -lua_gettop(L);
> +  const char *path = luaL_checkstring(L, n);
> +  n = -n;
> +  char **argv = (char**)malloc((n+1)*sizeof(char*));
> +  int i;
> +  pid_t ret;
> +  if (argv==NULL)
> +    return 0;
> +  argv[0] = (char*)path;
> +  for (i=1; i<n; i++) argv[i] = (char*)luaL_checkstring(L, -(n - i));
> +  argv[i] = NULL;
> +
> +  ret = process_execute_redirout(out, argv);
> +  free(argv);
> +  lua_pushnumber(L, ret);
> +  lua_pushstring(L, out.c_str());
> +  return 2;
> +}
> +
>  LUAEXT(wait, )
>  {
>    pid_t pid = static_cast<pid_t>(luaL_checknumber(L, -1));
> ============================================================

    Don't do this because:

1) It's deprecated. In Lua 5.1, negative arguments to the
luaL_check*() functions cause an error.
2) It's not needed. The stack is adjusted upon entry of Lua
CFunctions. Your arguments are in the range [1..lua_gettop(L)].

--
-alex
http://www.ventonegro.org/