/*

 * POSIX library for Lua 5.1, 5.2 & 5.3.

 * (c) Gary V. Vaughan <gary@vaughan.pe>, 2013-2015

 * (c) Reuben Thomas <rrt@sc3d.org> 2010-2013

 * (c) Natanael Copa <natanael.copa@gmail.com> 2008-2010

 * Clean up and bug fixes by Leo Razoumov <slonik.az@gmail.com> 2006-10-11

 * Luiz Henrique de Figueiredo <lhf@tecgraf.puc-rio.br> 07 Apr 2006 23:17:49

 * Based on original by Claudio Terra for Lua 3.x.

 * With contributions by Roberto Ierusalimschy.

 * With documentation from Steve Donovan 2012

 */

/***

 Wait for Process Termination.

@module posix.sys.wait

*/

#include <config.h>

#include <sys/wait.h>

#include "_helpers.c"

/***

Wait for child process to terminate.

@function wait

@int[opt=-1] pid child process id to wait for, or -1 for any child process

@int[opt] options bitwise OR of `WNOHANG` and `WUNTRACED`

@treturn[1] int pid of terminated child, if successful

@treturn[1] string "exited", "killed" or "stopped"

@treturn[1] int exit status, or signal number responsible for "killed" or "stopped"

@return[2] nil

@treturn[2] string error message

@treturn[2] int errnum

@see waitpid(2)

@see posix.unistd.fork

*/

static int

Pwait(lua_State *L)

{

	int status = 0;

	pid_t pid = optint(L, 1, -1);

	int options = optint(L, 2, 0);

	checknargs(L, 2);

	pid = waitpid(pid, &status, options);

	if (pid == -1)

		return pusherror(L, NULL);

	lua_pushinteger(L, pid);

	if (WIFEXITED(status))

	{

		lua_pushliteral(L,"exited");

		lua_pushinteger(L, WEXITSTATUS(status));

		return 3;

	}

	else if (WIFSIGNALED(status))

	{

		lua_pushliteral(L,"killed");

		lua_pushinteger(L, WTERMSIG(status));

		return 3;

	}

	else if (WIFSTOPPED(status))

	{

		lua_pushliteral(L,"stopped");

		lua_pushinteger(L, WSTOPSIG(status));

		return 3;

	}

	return 1;

}

static const luaL_Reg posix_sys_wait_fns[] =

{

	LPOSIX_FUNC( Pwait		),

	{NULL, NULL}

};

/***

Constants.

@section constants

*/

/***

Wait constants.

Any constants not available in the underlying system will be `nil` valued.

@table posix.sys.wait

@int WNOHANG don't block waiting

@int WUNTRACED report status of stopped children

@usage

  -- Print wait constants supported on this host.

  for name, value in pairs (require "posix.sys.wait") do

    if type (value) == "number" then

      print (name, value)

     end

  end

*/

LUALIB_API int

luaopen_posix_sys_wait(lua_State *L)

{

	luaL_register(L, "posix.sys.wait", posix_sys_wait_fns);

	lua_pushliteral(L, "posix.sys.wait for " LUA_VERSION " / " PACKAGE_STRING);

	lua_setfield(L, -2, "version");

	LPOSIX_CONST( WNOHANG		);

	LPOSIX_CONST( WUNTRACED		);

	return 1;

}