removed checkuserdata -- use 5.1 luaL_checkudata

fix check_file to work with a negative index (luaL_checkudata does not)
refactor spawn.c interface; use spawn_params_init instead of spawn_params_default; spawm_param_execute() creates proc
ex_pipe needs to create FILE* userdata with the __close environment table

posix/Makefile

@@ -1,5 +1,8 @@
 CFLAGS = -std=c99 $(WARNINGS) $(DEFINES) $(INCLUDES)
-DEFINES = -D_POSIX_SOURCE -D_XOPEN_SOURCE=600 -D_POSIX_C_SOURCE=200112L -U__STRICT_ANSI__ -DMISSING_POSIX_SPAWN
+DEFINES = -D_POSIX_SOURCE -D_XOPEN_SOURCE=600 -D_POSIX_C_SOURCE=200112L \
+	-U__STRICT_ANSI__ \
+	-D_GNU_SOURCE -DMISSING_POSIX_SPAWN \
+	-D'debug(...)=fprintf(stderr,__VA_ARGS__)'
 INCLUDES = -I$(LUA)/include
 WARNINGS = -W -Wall
 #LUA = /home/mark/src/lang/lua/lua-5.1-rc2

posix/ex.c

@@ -17,14 +17,7 @@
 #include "spawn.h"
 
 
-/* Generally useful function -- what luaL_checkudata() should do */
-extern void *checkuserdata(lua_State *L, int idx, const char *tname)
-{
-    void *ud;
-    luaL_argcheck(L, ud = luaL_checkudata(L, idx, tname), idx, tname);
-    return ud;
-}
-
+#define absindex(L,i) ((i)>0?(i):lua_gettop(L)+(i)+1)
 
 /* -- nil error */
 extern int push_error(lua_State *L)
@@ -123,9 +116,19 @@ static int ex_currentdir(lua_State *L)
 }
 
 
-static FILE *check_file(lua_State *L, int idx)
+FILE *check_file(lua_State *L, int idx, const char *argname)
 {
-	FILE **pf = checkuserdata(L, idx, LUA_FILEHANDLE);
+	FILE **pf;
+	if (idx > 0) pf = luaL_checkudata(L, idx, LUA_FILEHANDLE);
+	else {
+		idx = absindex(idx);
+		pf = lua_touserdata(L, idx);
+		luaL_getmetatable(L, LUA_FILEHANDLE);
+		if (!pf || !lua_getmetatable(L, idx) || !lua_rawequal(L, -1, -2))
+			luaL_error(L, "%s option: expected %s, got %s",
+				argname, LUA_FILEHANDLE, luaL_typename(L, idx));
+		lua_pop(L, 2);
+	}
 	if (!*pf) return luaL_error(L, "attempt to use a closed file"), NULL;
 	return *pf;
 }
@@ -142,7 +145,7 @@ static int ex_dirent(lua_State *L)
 			return push_error(L);
 		} break;
 	case LUA_TUSERDATA: {
-		FILE *f = check_file(L, 1);
+		FILE *f = check_file(L, 1, NULL);
 		if (-1 == fstat(fileno(f), &st))
 			return push_error(L);
 		} break;
@@ -186,9 +189,9 @@ static int diriter_setpathname(lua_State *L, int index)
 		lua_pushliteral(L, LUA_DIRSEP);
 		lua_concat(L, 2);
 	}
-	lua_pushvalue(L, index);               /* ... pathname diriter */
-	lua_insert(L, -2);                     /* ... diriter pathname */
-	lua_settable(L, LUA_REGISTRYINDEX);    /* ... */
+	lua_pushvalue(L, index);            /* ... pathname diriter */
+	lua_insert(L, -2);                  /* ... diriter pathname */
+	lua_settable(L, LUA_REGISTRYINDEX); /* ... */
 	return 0;
 }
 
@@ -216,32 +219,32 @@ static int ex_dir(lua_State *L)
 	default: return luaL_argerror(L, 1, "expected pathname");
 	case LUA_TSTRING:
 		pathname = lua_tostring(L, 1);
-		lua_pushcfunction(L, ex_dir);          /* pathname ... iter */
-		pi = lua_newuserdata(L, sizeof *pi);   /* pathname ... iter state */
+		lua_pushcfunction(L, ex_dir);       /* pathname ... iter */
+		pi = lua_newuserdata(L, sizeof *pi);/* pathname ... iter state */
 		pi->dir = opendir(pathname);
 		if (!pi->dir) return push_error(L);
-		luaL_getmetatable(L, DIR_HANDLE);      /* pathname ... iter state M */
-		lua_setmetatable(L, -2);               /* pathname ... iter state */
-		lua_pushvalue(L, 1);                   /* pathname ... iter state pathname */
-		diriter_setpathname(L, -2);            /* pathname ... iter state */
+		luaL_getmetatable(L, DIR_HANDLE);   /* pathname ... iter state M */
+		lua_setmetatable(L, -2);            /* pathname ... iter state */
+		lua_pushvalue(L, 1);                /* pathname ... iter state pathname */
+		diriter_setpathname(L, -2);         /* pathname ... iter state */
 		return 2;
 	case LUA_TUSERDATA:
-		pi = checkuserdata(L, 1, DIR_HANDLE);
+		pi = luaL_checkudata(L, 1, DIR_HANDLE);
 		d = readdir(pi->dir);
 		if (!d) {
 			closedir(pi->dir);
 			pi->dir = 0;
 			return push_error(L);
 		}
-		lua_newtable(L);                       /* diriter ... entry */
-		diriter_getpathname(L, 1);             /* diriter ... entry dirpath */
-		lua_pushstring(L, d->d_name);          /* diriter ... entry dirpath name */
-		lua_pushliteral(L, "name");            /* diriter ... entry dirpath name "name" */
-		lua_pushvalue(L, -2);                  /* diriter ... entry dirpath name "name" name */
-		lua_settable(L, -5);                   /* diriter ... entry dirpath name */
-		lua_concat(L, 2);                      /* diriter ... entry fullpath */
-		lua_replace(L, 1);                     /* fullpath ... entry */
-		lua_replace(L, 2);                     /* fullpath entry ... */
+		lua_newtable(L);                    /* diriter ... entry */
+		diriter_getpathname(L, 1);          /* diriter ... entry dirpath */
+		lua_pushstring(L, d->d_name);       /* diriter ... entry dirpath name */
+		lua_pushliteral(L, "name");         /* diriter ... entry dirpath name "name" */
+		lua_pushvalue(L, -2);               /* diriter ... entry dirpath name "name" name */
+		lua_settable(L, -5);                /* diriter ... entry dirpath name */
+		lua_concat(L, 2);                   /* diriter ... entry fullpath */
+		lua_replace(L, 1);                  /* fullpath ... entry */
+		lua_replace(L, 2);                  /* fullpath entry ... */
 		return ex_dirent(L);
 	}
 	/*NOTREACHED*/
@@ -269,7 +272,7 @@ static int file_lock(lua_State *L, FILE *f, const char *mode, long offset, long
 /* file mode [offset [length]] -- true/nil error */
 static int ex_lock(lua_State *L)
 {
-	FILE *f = check_file(L, 1);
+	FILE *f = check_file(L, 1, NULL);
 	const char *mode = luaL_checkstring(L, 2);
 	long offset = luaL_optnumber(L, 3, 0);
 	long length = luaL_optnumber(L, 4, 0);
@@ -310,86 +313,88 @@ static int ex_pipe(lua_State *L)
 	FILE *i, *o, **pf;
 	if (!make_pipe(&i, &o))
 		return push_error(L);
-	luaL_getmetatable(L, LUA_FILEHANDLE);
-	*(pf = lua_newuserdata(L, sizeof *pf)) = i;
-	lua_pushvalue(L, -2);
-	lua_setmetatable(L, -2);
-	*(pf = lua_newuserdata(L, sizeof *pf)) = o;
-	lua_pushvalue(L, -3);
-	lua_setmetatable(L, -2);
+	debug("make_pipe returns %p<-%p\n", i, o);
+	luaL_getmetatable(L, LUA_FILEHANDLE);       /* M */
+	*(pf = lua_newuserdata(L, sizeof *pf)) = i; /* M i */
+	lua_pushvalue(L, -2);                       /* M i M */
+	lua_setmetatable(L, -2);                    /* M i */
+	*(pf = lua_newuserdata(L, sizeof *pf)) = o; /* M i o */
+	lua_pushvalue(L, -3);                       /* M i o M */
+	lua_setmetatable(L, -2);                    /* M i o */
 	return 2;
 }
 
 
+static void get_redirect(lua_State *L, int idx, const char *stdname, struct spawn_params *p)
+{
+	lua_getfield(L, idx, stdname);
+	if (!lua_isnil(L, -1))
+		spawn_param_redirect(p, stdname, check_file(L, -1, stdname));
+	lua_pop(L, 1);
+}
+
 /* filename [args-opts] -- true/nil error */
 /* args-opts -- true/nil error */
 static int ex_spawn(lua_State *L)
 {
-	struct spawn_params params = {L};
-	struct process *proc;
+	struct spawn_params *params = spawn_param_init(L);
 
 	if (lua_type(L, 1) == LUA_TTABLE) {
-		lua_getfield(L, 1, "command");             /* opts ... cmd */
+		lua_getfield(L, 1, "command");          /* opts ... cmd */
 		if (!lua_isnil(L, -1)) {
 			/* convert {command=command,arg1,...} to command {arg1,...} */
-			lua_insert(L, 1);                      /* cmd opts ... */
+			lua_insert(L, 1);                   /* cmd opts ... */
 		}
 		else {
 			/* convert {arg0,arg1,...} to arg0 {arg1,...} */
 			size_t i, n = lua_objlen(L, 1);
-			lua_rawgeti(L, 1, 1);                  /* opts ... nil cmd */
-			if (lua_isnil(L, -1))
-				return luaL_error(L, "no command specified");
-			/* XXX check LUA_TSTRING */
-			lua_insert(L, 1);                      /* cmd opts ... nil */
+			lua_rawgeti(L, 1, 1);               /* opts ... nil cmd */
+			lua_insert(L, 1);                   /* cmd opts ... nil */
 			for (i = 2; i <= n; i++) {
-				lua_rawgeti(L, 2, i);              /* cmd opts ... nil argi */
-				lua_rawseti(L, 2, i - 1);          /* cmd opts ... nil */
+				lua_rawgeti(L, 2, i);           /* cmd opts ... nil argi */
+				lua_rawseti(L, 2, i - 1);       /* cmd opts ... nil */
 			}
-			lua_rawseti(L, 2, n);                  /* cmd opts ... */
+			lua_rawseti(L, 2, n);               /* cmd opts ... */
 		}
 	}
 
 	/* get filename to execute */
-	spawn_param_filename(&params);
+	if (lua_type(L, 1) != LUA_TSTRING)
+		return luaL_error(L, "command option: expected string, got %s", luaL_typename(L, 1));
+	spawn_param_filename(params, lua_tostring(L, 1));
 
 	/* get arguments, environment, and redirections */
 	switch (lua_type(L, 2)) {
 	default: return luaL_argerror(L, 2, "expected options table");
-	case LUA_TNONE:
-		spawn_param_defaults(&params);             /* cmd opts ... */
-		break;
+	case LUA_TNONE: break;
 	case LUA_TTABLE:
-		lua_getfield(L, 2, "args");                /* cmd opts ... argtab */
+		lua_getfield(L, 2, "args");             /* cmd opts ... argtab */
 		switch (lua_type(L, -1)) {
 		default: return luaL_error(L, "args option must be an array");
 		case LUA_TNIL:
-			lua_pop(L, 1);                         /* cmd opts ... */
-			lua_pushvalue(L, 2);                   /* cmd opts ... opts */
+			lua_pop(L, 1);                      /* cmd opts ... */
+			lua_pushvalue(L, 2);                /* cmd opts ... opts */
 			if (0) /*FALLTHRU*/
 		case LUA_TTABLE:
 			if (lua_objlen(L, 2) > 0)
 				return luaL_error(L, "cannot specify both the args option and array values");
-			spawn_param_args(&params);             /* cmd opts ... */
+			spawn_param_args(params);           /* cmd opts ... */
 			break;
 		}
-		lua_getfield(L, 2, "env");                 /* cmd opts ... envtab */
+		lua_getfield(L, 2, "env");              /* cmd opts ... envtab */
 		switch (lua_type(L, -1)) {
 		default: return luaL_error(L, "env option must be a table");
 		case LUA_TNIL:
 		case LUA_TTABLE:
-			spawn_param_env(&params);              /* cmd opts ... */
+			spawn_param_env(params);            /* cmd opts ... */
 			break;
 		}
-		spawn_param_redirects(&params);            /* cmd opts ... */
+		get_redirect(L, 2, "stdin", params);    /* cmd opts ... */
+		get_redirect(L, 2, "stdout", params);   /* cmd opts ... */
+		get_redirect(L, 2, "stderr", params);   /* cmd opts ... */
 		break;
 	}
-	proc = lua_newuserdata(L, sizeof *proc);       /* cmd opts ... proc */
-	luaL_getmetatable(L, PROCESS_HANDLE);          /* cmd opts ... proc M */
-	lua_setmetatable(L, -2);                       /* cmd opts ... proc */
-	if (!spawn_param_execute(&params, proc))
-		return push_error(L);
-	return 1; /* ... proc */
+	return spawn_param_execute(params);         /* proc/nil error */
 }
 
 
@@ -422,47 +427,69 @@ static const luaL_reg ex_oslib[] = {
 };
 static const luaL_reg ex_diriter_methods[] = {
 	{"__gc",       diriter_close},
+/*	{"__tostring", diriter_tostring}, */
 	{0,0}
 };
 static const luaL_reg ex_process_methods[] = {
-	{"wait",       process_wait},
 	{"__tostring", process_tostring},
+	{"wait",       process_wait},
 	{0,0}
 };
 
+/* copy the fields given in 'l' from one table to another; insert missing fields */
+static void copy_fields(lua_State *L, const luaL_reg *l, int from, int to)
+{
+	from = absindex(L, from);
+	to = absindex(L, to);
+	for (; l->name; l++) {
+		lua_getfield(L, from, l->name);
+		if (lua_isnil(L, -1)) {
+			lua_pop(L, 1);
+			lua_pushcfunction(L, l->func);
+		}
+		lua_setfield(L, to, l->name);
+	}
+}
+
 int luaopen_ex(lua_State *L)
 {
-	/* extend the io table */
-	lua_getglobal(L, "io");
-	if (lua_isnil(L, -1)) return luaL_error(L, "io not loaded");
-	luaL_openlib(L, 0, ex_iolib, 0);
+	/* Make all functions available via ex. namespace */
+	luaL_register(L, "ex", ex_iolib);           /* . ex */
+	luaL_register(L, 0, ex_oslib);
+	luaL_register(L, 0, ex_iofile_methods);
+	luaL_register(L, 0, ex_process_methods + 1); /* XXX don't insert __tostring */
+	lua_replace(L, 1);                          /* ex . */
 
 	/* extend the os table */
-	lua_getglobal(L, "os");
+	lua_getglobal(L, "os");                     /* ex . os */
 	if (lua_isnil(L, -1)) return luaL_error(L, "os not loaded");
-	luaL_openlib(L, "os", ex_oslib, 0);
+	copy_fields(L, ex_oslib, 1, -1);            /* ex . os */
+
+	/* extend the io table */
+	lua_getglobal(L, "io");                     /* ex . io */
+	if (lua_isnil(L, -1)) return luaL_error(L, "io not loaded");
+	copy_fields(L, ex_iolib, 1, -1);            /* ex . io */
+	lua_getfield(L, 1, "pipe");                 /* ex . io ex_pipe */
+	lua_getfield(L, -2, "stderr");              /* ex . io ex_pipe io_stderr */
+	lua_getfenv(L, -1);                         /* ex . io ex_pipe io_stderr E */
+	lua_setfenv(L, -3);                         /* ex . io ex_pipe io_stderr */
 
 	/* extend the io.file metatable */
-	luaL_getmetatable(L, LUA_FILEHANDLE);
+	luaL_getmetatable(L, LUA_FILEHANDLE);       /* ex . F  */
 	if (lua_isnil(L, -1)) return luaL_error(L, "can't find FILE* metatable");
-	luaL_openlib(L, 0, ex_iofile_methods, 0);
+	copy_fields(L, ex_iofile_methods, 1, -1);   /* ex . F */
 
 	/* diriter metatable */
-	luaL_newmetatable(L, DIR_HANDLE);
-	luaL_openlib(L, 0, ex_diriter_methods, 0);
+	luaL_newmetatable(L, DIR_HANDLE);           /* ex . D */
+	luaL_register(L, 0, ex_diriter_methods);    /* ex . D */
 
 	/* proc metatable */
-	luaL_newmetatable(L, PROCESS_HANDLE);       /* proc */
-	luaL_openlib(L, 0, ex_process_methods, 0);  /* proc */
-	lua_pushliteral(L, "__index");              /* proc __index */
-	lua_pushvalue(L, -2);                       /* proc __index proc */
-	lua_settable(L, -3);                        /* proc */
-
-	/* Make all functions available via ex. namespace */
-	luaL_openlib(L, "ex", ex_iolib, 0);
-	luaL_openlib(L, 0, ex_oslib, 0);
-	luaL_openlib(L, 0, ex_iofile_methods, 0);
-	luaL_openlib(L, 0, ex_process_methods, 0);
+	luaL_newmetatable(L, PROCESS_HANDLE);       /* ex . P */
+	copy_fields(L, ex_process_methods, 1, -1);  /* ex . P */
+	lua_pushliteral(L, "__index");              /* ex . P __index */
+	lua_pushvalue(L, -2);                       /* ex . P __index P */
+	lua_settable(L, -3);                        /* ex . P */
 
+	lua_settop(L, 1);                           /* ex */
 	return 1;
 }

posix/spawn.c

@@ -4,27 +4,36 @@
 
 #include <unistd.h>
 #include <sys/wait.h>
+#ifndef MISSING_POSIX_SPAWN
+#include <spawn.h>
+#else
+#include "posix_spawn.h"
+#endif
 
 #include "spawn.h"
 
+struct spawn_params {
+	lua_State *L;
+	const char *command, **argv, **envp;
+	posix_spawn_file_actions_t redirect;
+};
+
 extern int push_error(lua_State *L);
-extern void *checkuserdata(lua_State *L, int index, const char *name);
+extern FILE *check_file(lua_State *L, int idx, const char *argname);
 
-/* filename ... */
-void spawn_param_filename(struct spawn_params *p)
+struct spawn_params *spawn_param_init(lua_State *L)
 {
-	/* XXX confusing */
-	p->command = luaL_checkstring(p->L, 1);
+	struct spawn_params *p = lua_newuserdata(L, sizeof *p);
+	p->L = L;
+	p->command = 0;
+	p->argv = p->envp = 0;
+	posix_spawn_file_actions_init(&p->redirect);
+	return p;
 }
 
-/* -- */
-void spawn_param_defaults(struct spawn_params *p)
+void spawn_param_filename(struct spawn_params *p, const char *filename)
 {
-	p->argv = lua_newuserdata(p->L, 2 * sizeof *p->argv);
-	p->argv[0] = p->command;
-	p->argv[1] = 0;
-	p->envp = (const char **)environ;
-	p->has_actions = 0;
+	p->command = filename;
 }
 
 /* Converts a Lua array of strings to a null-terminated array of char pointers.
@@ -86,44 +95,50 @@ void spawn_param_env(struct spawn_params *p)
 	make_vector(p->L);                     /* ... arr */
 }
 
-/* _ opts ... */
-static int get_redirect(struct spawn_params *p, const char *stdname, int descriptor)
+void spawn_param_redirect(struct spawn_params *p, const char *stdname, FILE *f)
 {
-	int ret;
-	lua_getfield(p->L, 2, stdname);
-	if ((ret = !lua_isnil(p->L, -1)))
-		/* XXX checkuserdata is confusing here */
-		posix_spawn_file_actions_adddup2(&p->file_actions, 
-			fileno(checkuserdata(p->L, -1, LUA_FILEHANDLE)), descriptor);
-	lua_pop(p->L, 1);
-	return ret;
+	int d;
+	switch (stdname[3]) {
+	case 'i': d = STDIN_FILENO; break;
+	case 'o': d = STDOUT_FILENO; break;
+	case 'e': d = STDERR_FILENO; break;
+	}
+	debug("duplicating %d to %d\n", fileno(f), d);
+	posix_spawn_file_actions_adddup2(&p->redirect, fileno(f), d);
 }
 
-/* _ opts ... */
-void spawn_param_redirects(struct spawn_params *p)
-{
-	posix_spawn_file_actions_init(&p->file_actions);
-	p->has_actions = 1;
-	get_redirect(p, "stdin", STDIN_FILENO);
-	get_redirect(p, "stdout", STDOUT_FILENO);
-	get_redirect(p, "stderr", STDERR_FILENO);
-}
+struct process {
+	int status;
+	pid_t pid;
+};
 
-int spawn_param_execute(struct spawn_params *p, struct process *proc)
+int spawn_param_execute(struct spawn_params *p)
 {
+	lua_State *L = p->L;
+	struct process *proc = lua_newuserdata(L, sizeof *proc);
 	int ret;
+	luaL_getmetatable(L, PROCESS_HANDLE);
+	lua_setmetatable(L, -2);
 	proc->status = -1;
-	ret = posix_spawnp(&proc->pid, p->command, &p->file_actions, 0, (char *const *)p->argv, (char *const *)p->envp);
-	if (p->has_actions)
-		posix_spawn_file_actions_destroy(&p->file_actions);
-	return ret == 0;
+	if (!p->argv) {
+		p->argv = lua_newuserdata(L, 2 * sizeof *p->argv);
+		p->argv[0] = p->command;
+		p->argv[1] = 0;
+	}
+	if (!p->envp)
+		p->envp = (const char **)environ;
+	ret = posix_spawnp(&proc->pid, p->command, &p->redirect, 0, (char *const *)p->argv, (char *const *)p->envp);
+	posix_spawn_file_actions_destroy(&p->redirect);
+	return ret != 0 ? push_error(L) : 1;
 }
 
 
+extern int push_error(lua_State *L);
+
 /* proc -- exitcode/nil error */
 int process_wait(lua_State *L)
 {
-	struct process *p = checkuserdata(L, 1, PROCESS_HANDLE);
+	struct process *p = luaL_checkudata(L, 1, PROCESS_HANDLE);
 	if (p->status == -1) {
 		int status;
 		if (-1 == waitpid(p->pid, &status, 0))
@@ -137,7 +152,7 @@ int process_wait(lua_State *L)
 /* proc -- string */
 int process_tostring(lua_State *L)
 {
-	struct process *p = checkuserdata(L, 1, PROCESS_HANDLE);
+	struct process *p = luaL_checkudata(L, 1, PROCESS_HANDLE);
 	char buf[40];
 	lua_pushlstring(L, buf,
 		sprintf(buf, "process (%lu, %s)", (unsigned long)p->pid,

posix/spawn.h

@@ -1,32 +1,18 @@
 #ifndef SPAWN_H
 #define SPAWN_H
 
-#ifdef MISSING_POSIX_SPAWN
-#include "posix_spawn.h"
-#endif
-
 #include <lua.h>
-#include <sys/types.h>
 
 #define PROCESS_HANDLE "process"
-struct process {
-	int status;
-	pid_t pid;
-};
-
-struct spawn_params {
-	lua_State *L;
-	const char *command, **argv, **envp;
-	posix_spawn_file_actions_t file_actions;
-	int has_actions;
-};
+struct process;
+struct spawn_params;
 
-void spawn_param_filename(struct spawn_params *p);
-void spawn_param_defaults(struct spawn_params *p);
+struct spawn_params *spawn_param_init(lua_State *L);
+void spawn_param_filename(struct spawn_params *p, const char *filename);
 void spawn_param_args(struct spawn_params *p);
 void spawn_param_env(struct spawn_params *p);
-void spawn_param_redirects(struct spawn_params *p);
-int spawn_param_execute(struct spawn_params *p, struct process *proc);
+void spawn_param_redirect(struct spawn_params *p, const char *stdname, FILE *f);
+int spawn_param_execute(struct spawn_params *p);
 int process_wait(lua_State *L);
 int process_tostring(lua_State *L);
 

tests/rt5.lua

@@ -1,7 +1,7 @@
 #!/usr/bin/env lua
 require "ex"
 
-local proc
-proc = assert(os.spawn(arg[1]))
+assert(arg[1], "argument required")
+local proc = assert(os.spawn(arg[1]))
 print(proc)
 print(assert(proc:wait()))

tests/rt6.lua

@@ -0,0 +1,14 @@
+#!/usr/bin/env lua
+require "ex"
+
+for e in assert(os.dir(".")) do
+	print(string.format("%.3s %9d  %s", e.type or 'Unknown', e.size or -1, e.name))
+end
+--[[
+local f,s,i = assert(os.dir(".."))
+print(f,s,i)
+i=assert(f(s,i))
+for e in f,s,i do
+	print(e.name,e.type,e.size)
+end
+--]]

tests/rt7.lua

@@ -0,0 +1,18 @@
+#!/usr/bin/env lua
+require "ex"
+assert(arg[1], "need a command name")
+print"io.pipe()"
+local i, o = assert(io.pipe())
+print("got", i, o)
+print"os.spawn()"
+local t = {command = arg[1], stdin = i}
+print(t.stdin)
+local proc = assert(os.spawn(t))
+print"i:close()"
+i:close()
+print"o:write()"
+o:write("Hello\nWorld\n")
+print"o:close()"
+o:close()
+print"proc:wait()"
+print("exit status:", assert(proc:wait()))

w32api/ex.c

@@ -15,13 +15,7 @@
 #include "spawn.h"
 
 
-/* Generally useful function -- what luaL_checkudata() should do */
-extern void *checkuserdata(lua_State *L, int idx, const char *tname)
-{
-    void *ud;
-    luaL_argcheck(L, ud = luaL_checkudata(L, idx, tname), idx, tname);
-    return ud;
-}
+#define absindex(L,i) ((i)>0?(i):lua_gettop(L)+(i)+1)
 
 /* return HANDLE from a FILE */
 extern HANDLE get_handle(FILE *f)
@@ -144,9 +138,19 @@ static int ex_currentdir(lua_State *L)
 }
 
 
-static FILE *check_file(lua_State *L, int idx)
+FILE *check_file(lua_State *L, int idx, const char *argname)
 {
-	FILE **pf = checkuserdata(L, idx, LUA_FILEHANDLE);
+	FILE **pf;
+	if (idx > 0) pf = luaL_checkudata(L, idx, LUA_FILEHANDLE);
+	else {
+		idx = absindex(idx);
+		pf = lua_touserdata(L, idx);
+		luaL_getmetatable(L, LUA_FILEHANDLE);
+		if (!pf || !lua_getmetatable(L, idx - 1) || !lua_rawequal(L, -1, -2))
+			luaL_error(L, "%s option: expected %s, got %s",
+				argname, LUA_FILEHANDLE, luaL_typename(L, idx - 2));
+		lua_pop(L, 2);
+	}
 	if (!*pf) return luaL_error(L, "attempt to use a closed file"), NULL;
 	return *pf;
 }
@@ -187,7 +191,7 @@ static int ex_dirent(lua_State *L)
 			size = get_size(name);
 		} break;
 	case LUA_TUSERDATA: {
-		FILE *f = check_file(L, 1);
+		FILE *f = check_file(L, 1, NULL);
 		BY_HANDLE_FILE_INFORMATION info;
 		if (!GetFileInformationByHandle(get_handle(f), &info))
 			return push_error(L);
@@ -235,9 +239,9 @@ static int diriter_setpathname(lua_State *L, int index)
 		lua_pushliteral(L, LUA_DIRSEP);
 		lua_concat(L, 2);
 	}
-	lua_pushvalue(L, index);               /* ... pathname diriter */
-	lua_insert(L, -2);                     /* ... diriter pathname */
-	lua_settable(L, LUA_REGISTRYINDEX);    /* ... */
+	lua_pushvalue(L, index);            /* ... pathname diriter */
+	lua_insert(L, -2);                  /* ... diriter pathname */
+	lua_settable(L, LUA_REGISTRYINDEX); /* ... */
 	return 0;
 }
 
@@ -263,37 +267,37 @@ static int ex_dir(lua_State *L)
 	switch (lua_type(L, 1)) {
 	default: return luaL_argerror(L, 1, "expected pathname");
 	case LUA_TSTRING:
-		lua_pushvalue(L, 1);                   /* pathname ... pathname */
-		lua_pushliteral(L, "\\*");             /* pathname ... pathname "\\*" */
-		lua_concat(L, 2);                      /* pathname ... pattern */
+		lua_pushvalue(L, 1);                /* pathname ... pathname */
+		lua_pushliteral(L, "\\*");          /* pathname ... pathname "\\*" */
+		lua_concat(L, 2);                   /* pathname ... pattern */
 		pathname = lua_tostring(L, -1);
-		lua_pushcfunction(L, ex_dir);          /* pathname ... pat iter */
-		pi = lua_newuserdata(L, sizeof *pi);   /* pathname ... pat iter state */
+		lua_pushcfunction(L, ex_dir);       /* pathname ... pat iter */
+		pi = lua_newuserdata(L, sizeof *pi);/* pathname ... pat iter state */
 		pi->hf = FindFirstFile(pathname, &pi->fd);
 		if (pi->hf == INVALID_HANDLE_VALUE)
 			return push_error(L);
-		luaL_getmetatable(L, DIR_HANDLE);      /* pathname ... pat iter state M */
-		lua_setmetatable(L, -2);               /* pathname ... pat iter state */
-		lua_pushvalue(L, 1);                   /* pathname ... pat iter state pathname */
-		diriter_setpathname(L, -2);            /* pathname ... pat iter state */
+		luaL_getmetatable(L, DIR_HANDLE);   /* pathname ... pat iter state M */
+		lua_setmetatable(L, -2);            /* pathname ... pat iter state */
+		lua_pushvalue(L, 1);                /* pathname ... pat iter state pathname */
+		diriter_setpathname(L, -2);         /* pathname ... pat iter state */
 		return 2;
 	case LUA_TUSERDATA:
-		pi = checkuserdata(L, 1, DIR_HANDLE);
+		pi = luaL_checkudata(L, 1, DIR_HANDLE);
 		if (pi->hf == INVALID_HANDLE_VALUE)
 			return 0;
-		lua_newtable(L);                       /* diriter ... entry */
-		diriter_getpathname(L, 1);             /* diriter ... entry dirpath */
-		lua_pushstring(L, pi->fd.cFileName);   /* diriter ... entry dirpath name */
-		lua_pushliteral(L, "name");            /* diriter ... entry dirpath name "name" */
-		lua_pushvalue(L, -2);                  /* diriter ... entry dirpath name "name" name */
-		lua_settable(L, -5);                   /* diriter ... entry dirpath name */
-		lua_concat(L, 2);                      /* diriter ... entry fullpath */
+		lua_newtable(L);                    /* diriter ... entry */
+		diriter_getpathname(L, 1);          /* diriter ... entry dirpath */
+		lua_pushstring(L, pi->fd.cFileName);/* diriter ... entry dirpath name */
+		lua_pushliteral(L, "name");         /* diriter ... entry dirpath name "name" */
+		lua_pushvalue(L, -2);               /* diriter ... entry dirpath name "name" name */
+		lua_settable(L, -5);                /* diriter ... entry dirpath name */
+		lua_concat(L, 2);                   /* diriter ... entry fullpath */
 		if (!FindNextFile(pi->hf, &pi->fd)) {
 			FindClose(pi->hf);
 			pi->hf = INVALID_HANDLE_VALUE;
 		}
-		lua_replace(L, 1);                     /* fullpath ... entry */
-		lua_replace(L, 2);                     /* fullpath entry ... */
+		lua_replace(L, 1);                  /* fullpath ... entry */
+		lua_replace(L, 2);                  /* fullpath entry ... */
 		return ex_dirent(L);
 	}
 	/*NOTREACHED*/
@@ -304,8 +308,8 @@ static int file_lock(lua_State *L, FILE *f, const char *mode, long offset, long
 {
 	HANDLE h = get_handle(f);
 	DWORD flags;
-	LARGE_INTEGER len = {0};
-	OVERLAPPED ov = {0};
+	LARGE_INTEGER len = {0,0};
+	OVERLAPPED ov = {.hEvent = INVALID_HANDLE_VALUE};
 	BOOL ret;
 	if (length) len.LowPart = length;
 	else len.LowPart = GetFileSize(h, &len.HighPart);
@@ -327,7 +331,7 @@ static int file_lock(lua_State *L, FILE *f, const char *mode, long offset, long
 /* file mode [offset [length]] -- true/nil error */
 static int ex_lock(lua_State *L)
 {
-	FILE *f = check_file(L, 1);
+	FILE *f = check_file(L, 1, NULL);
 	const char *mode = luaL_checkstring(L, 2);
 	long offset = luaL_optnumber(L, 3, 0);
 	long length = luaL_optnumber(L, 4, 0);
@@ -362,86 +366,87 @@ static int ex_pipe(lua_State *L)
 	FILE *i, *o, **pf;
 	if (!make_pipe(&i, &o))
 		return push_error(L);
-	luaL_getmetatable(L, LUA_FILEHANDLE);
-	*(pf = lua_newuserdata(L, sizeof *pf)) = i;
-	lua_pushvalue(L, -2);
-	lua_setmetatable(L, -2);
-	*(pf = lua_newuserdata(L, sizeof *pf)) = o;
-	lua_pushvalue(L, -3);
-	lua_setmetatable(L, -2);
+	luaL_getmetatable(L, LUA_FILEHANDLE);       /* M */
+	*(pf = lua_newuserdata(L, sizeof *pf)) = i; /* M i */
+	lua_pushvalue(L, -2);                       /* M i M */
+	lua_setmetatable(L, -2);                    /* M i */
+	*(pf = lua_newuserdata(L, sizeof *pf)) = o; /* M i o */
+	lua_pushvalue(L, -3);                       /* M i o M */
+	lua_setmetatable(L, -2);                    /* M i o */
 	return 2;
 }
 
 
+static void get_redirect(lua_State *L, int idx, const char *stdname, struct spawn_params *p)
+{
+	lua_getfield(L, idx, stdname);
+	if (!lua_isnil(L, -1))
+		spawn_param_redirect(p, stdname, check_file(L, -1, stdname));
+	lua_pop(L, 1);
+}
+
 /* filename [args-opts] -- true/nil error */
 /* args-opts -- true/nil error */
 static int ex_spawn(lua_State *L)
 {
-	struct spawn_params params = {L};
-	struct process *proc;
+	struct spawn_params *params = spawn_param_init(L);
 
 	if (lua_type(L, 1) == LUA_TTABLE) {
-		lua_getfield(L, 1, "command");             /* opts ... cmd */
+		lua_getfield(L, 1, "command");          /* opts ... cmd */
 		if (!lua_isnil(L, -1)) {
 			/* convert {command=command,arg1,...} to command {arg1,...} */
-			lua_insert(L, 1);                      /* cmd opts ... */
+			lua_insert(L, 1);                   /* cmd opts ... */
 		}
 		else {
 			/* convert {arg0,arg1,...} to arg0 {arg1,...} */
 			size_t i, n = lua_objlen(L, 1);
-			lua_rawgeti(L, 1, 1);                  /* opts ... nil cmd */
-			if (lua_isnil(L, -1))
-				return luaL_error(L, "no command specified");
-			/* XXX check LUA_TSTRING */
-			lua_insert(L, 1);                      /* cmd opts ... nil */
+			lua_rawgeti(L, 1, 1);               /* opts ... nil cmd */
+			lua_insert(L, 1);                   /* cmd opts ... nil */
 			for (i = 2; i <= n; i++) {
-				lua_rawgeti(L, 2, i);              /* cmd opts ... nil argi */
-				lua_rawseti(L, 2, i - 1);          /* cmd opts ... nil */
+				lua_rawgeti(L, 2, i);           /* cmd opts ... nil argi */
+				lua_rawseti(L, 2, i - 1);       /* cmd opts ... nil */
 			}
-			lua_rawseti(L, 2, n);                  /* cmd opts ... */
+			lua_rawseti(L, 2, n);               /* cmd opts ... */
 		}
 	}
 
 	/* get filename to execute */
-	spawn_param_filename(&params);
+	if (lua_type(L, 1) != LUA_TSTRING)
+		return luaL_error(L, "command option: expected string, got %s", luaL_typename(L, 1));
+	spawn_param_filename(params, lua_tostring(L, 1));
 
 	/* get arguments, environment, and redirections */
 	switch (lua_type(L, 2)) {
 	default: return luaL_argerror(L, 2, "expected options table");
-	case LUA_TNONE:
-		spawn_param_defaults(&params);             /* cmd opts ... */
-		break;
+	case LUA_TNONE: break;
 	case LUA_TTABLE:
-		lua_getfield(L, 2, "args");                /* cmd opts ... argtab */
+		lua_getfield(L, 2, "args");             /* cmd opts ... argtab */
 		switch (lua_type(L, -1)) {
 		default: return luaL_error(L, "args option must be an array");
 		case LUA_TNIL:
-			lua_pop(L, 1);                         /* cmd opts ... */
-			lua_pushvalue(L, 2);                   /* cmd opts ... opts */
+			lua_pop(L, 1);                      /* cmd opts ... */
+			lua_pushvalue(L, 2);                /* cmd opts ... opts */
 			if (0) /*FALLTHRU*/
 		case LUA_TTABLE:
 			if (lua_objlen(L, 2) > 0)
 				return luaL_error(L, "cannot specify both the args option and array values");
-			spawn_param_args(&params);             /* cmd opts ... */
+			spawn_param_args(params);           /* cmd opts ... */
 			break;
 		}
-		lua_getfield(L, 2, "env");                 /* cmd opts ... envtab */
+		lua_getfield(L, 2, "env");              /* cmd opts ... envtab */
 		switch (lua_type(L, -1)) {
 		default: return luaL_error(L, "env option must be a table");
 		case LUA_TNIL:
 		case LUA_TTABLE:
-			spawn_param_env(&params);              /* cmd opts ... */
+			spawn_param_env(params);            /* cmd opts ... */
 			break;
 		}
-		spawn_param_redirects(&params);            /* cmd opts ... */
+		get_redirect(L, 2, "stdin", params);    /* cmd opts ... */
+		get_redirect(L, 2, "stdout", params);   /* cmd opts ... */
+		get_redirect(L, 2, "stderr", params);   /* cmd opts ... */
 		break;
 	}
-	proc = lua_newuserdata(L, sizeof *proc);       /* cmd opts ... proc */
-	luaL_getmetatable(L, PROCESS_HANDLE);          /* cmd opts ... proc M */
-	lua_setmetatable(L, -2);                       /* cmd opts ... proc */
-	if (!spawn_param_execute(&params, proc))
-		return push_error(L);
-	return 1; /* ... proc */
+	return spawn_param_execute(params);         /* proc/nil error */
 }
 
 
@@ -474,47 +479,69 @@ static const luaL_reg ex_oslib[] = {
 };
 static const luaL_reg ex_diriter_methods[] = {
 	{"__gc",       diriter_close},
+/*	{"__tostring", diriter_tostring}, */
 	{0,0}
 };
 static const luaL_reg ex_process_methods[] = {
-	{"wait",       process_wait},
 	{"__tostring", process_tostring},
+	{"wait",       process_wait},
 	{0,0}
 };
 
+/* copy the fields given in 'l' from one table to another; insert missing fields */
+static void copy_fields(lua_State *L, const luaL_reg *l, int from, int to)
+{
+	from = absindex(L, from);
+	to = absindex(L, to);
+	for (; l->name; l++) {
+		lua_getfield(L, from, l->name);
+		if (lua_isnil(L, -1)) {
+			lua_pop(L, 1);
+			lua_pushcfunction(L, l->func);
+		}
+		lua_setfield(L, to, l->name);
+	}
+}
+
 int luaopen_ex(lua_State *L)
 {
-	/* extend the io table */
-	lua_getglobal(L, "io");
-	if (lua_isnil(L, -1)) return luaL_error(L, "io not loaded");
-	luaL_openlib(L, 0, ex_iolib, 0);
+	/* Make all functions available via ex. namespace */
+	luaL_register(L, "ex", ex_iolib);           /* . ex */
+	luaL_register(L, 0, ex_oslib);
+	luaL_register(L, 0, ex_iofile_methods);
+	luaL_register(L, 0, ex_process_methods + 1); /* XXX don't insert __tostring */
+	lua_replace(L, 1);                          /* ex . */
 
 	/* extend the os table */
-	lua_getglobal(L, "os");
+	lua_getglobal(L, "os");                     /* ex . os */
 	if (lua_isnil(L, -1)) return luaL_error(L, "os not loaded");
-	luaL_openlib(L, "os", ex_oslib, 0);
+	copy_fields(L, ex_oslib, 1, -1);            /* ex . os */
+
+	/* extend the io table */
+	lua_getglobal(L, "io");                     /* ex . io */
+	if (lua_isnil(L, -1)) return luaL_error(L, "io not loaded");
+	copy_fields(L, ex_iolib, 1, -1);            /* ex . io */
+	lua_getfield(L, 1, "pipe");                 /* ex . io ex_pipe */
+	lua_getfield(L, -2, "stderr");              /* ex . io ex_pipe io_stderr */
+	lua_getfenv(L, -1);                         /* ex . io ex_pipe io_stderr E */
+	lua_setfenv(L, -3);                         /* ex . io ex_pipe io_stderr */
 
 	/* extend the io.file metatable */
-	luaL_getmetatable(L, LUA_FILEHANDLE);
+	luaL_getmetatable(L, LUA_FILEHANDLE);       /* ex . F  */
 	if (lua_isnil(L, -1)) return luaL_error(L, "can't find FILE* metatable");
-	luaL_openlib(L, 0, ex_iofile_methods, 0);
+	copy_fields(L, ex_iofile_methods, 1, -1);   /* ex . F */
 
 	/* diriter metatable */
-	luaL_newmetatable(L, DIR_HANDLE);
-	luaL_openlib(L, 0, ex_diriter_methods, 0);
+	luaL_newmetatable(L, DIR_HANDLE);           /* ex . D */
+	luaL_register(L, 0, ex_diriter_methods);    /* ex . D */
 
 	/* proc metatable */
-	luaL_newmetatable(L, PROCESS_HANDLE);       /* proc */
-	luaL_openlib(L, 0, ex_process_methods, 0);  /* proc */
-	lua_pushliteral(L, "__index");              /* proc __index */
-	lua_pushvalue(L, -2);                       /* proc __index proc */
-	lua_settable(L, -3);                        /* proc */
-
-	/* Make all functions available via ex. namespace */
-	luaL_openlib(L, "ex", ex_iolib, 0);
-	luaL_openlib(L, 0, ex_oslib, 0);
-	luaL_openlib(L, 0, ex_iofile_methods, 0);
-	luaL_openlib(L, 0, ex_process_methods, 0);
+	luaL_newmetatable(L, PROCESS_HANDLE);       /* ex . P */
+	copy_fields(L, ex_process_methods, 1, -1);  /* ex . P */
+	lua_pushliteral(L, "__index");              /* ex . P __index */
+	lua_pushvalue(L, -2);                       /* ex . P __index P */
+	lua_settable(L, -3);                        /* ex . P */
 
+	lua_settop(L, 1);                           /* ex */
 	return 1;
 }

w32api/spawn.c

@@ -8,7 +8,10 @@
 
 #include "spawn.h"
 
-extern void *checkuserdata(lua_State *L, int index, const char *name);
+#include <assert.h>
+#define debug(...) fprintf(stderr, __VA_ARGS__)
+#include "../lds.c"
+
 extern HANDLE get_handle(FILE *f);
 extern int push_error(lua_State *L);
 
@@ -17,33 +20,45 @@ static int needs_quoting(const char *s)
 	return s[0] != '"' && strchr(s, ' ');
 }
 
-/* filename ... */
-void spawn_param_filename(struct spawn_params *p)
-{
-	/* XXX luaL_checkstring is confusing here */
-	p->cmdline = luaL_checkstring(p->L, 1);
-	if (needs_quoting(p->cmdline)) {
-		lua_pushliteral(p->L, "\"");   /* cmd ... q */
-		lua_pushvalue(p->L, 1);        /* cmd ... q cmd */
-		lua_pushvalue(p->L, -2);       /* cmd ... q cmd q */
-		lua_concat(p->L, 3);           /* cmd ... "cmd" */
-		lua_replace(p->L, 1);          /* "cmd" ... */
-		p->cmdline = lua_tostring(p->L, 1);
-	}
-}
+struct spawn_params {
+	lua_State *L;
+	const char *cmdline;
+	const char *environment;
+	STARTUPINFO si;
+};
 
-/* -- */
-void spawn_param_defaults(struct spawn_params *p)
+struct spawn_params *spawn_param_init(lua_State *L)
 {
+	struct spawn_params *p = lua_newuserdata(L, sizeof *p);
+	p->L = L;
+	p->cmdline = 0;
 	p->environment = 0;
 	memset(&p->si, 0, sizeof p->si);
-	p->si.cb = sizeof p->si;
+	p->si.cb = 0;
+	p->si.hStdInput  = GetStdHandle(STD_INPUT_HANDLE);
+	p->si.hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);
+	p->si.hStdError  = GetStdHandle(STD_ERROR_HANDLE);
+	return p;
+}
+
+/* filename ... */
+void spawn_param_filename(struct spawn_params *p, const char *filename)
+{
+	p->cmdline = filename;
+	if (needs_quoting(p->cmdline)) {
+		lua_pushliteral(p->L, "\"");       /* cmd ... q */
+		lua_pushstring(p->L, p->cmdline);  /* cmd ... q cmd */
+		lua_pushvalue(p->L, -2);           /* cmd ... q cmd q */
+		lua_concat(p->L, 3);               /* cmd ... "cmd" */
+		p->cmdline = lua_tostring(p->L, -1);
+	}
 }
 
 /* cmd opts ... argtab -- cmd opts ... cmdline */
 void spawn_param_args(struct spawn_params *p)
 {
 	lua_State *L = p->L;
+	debug("spawn_param_args:"); debug_stack(L);
 	luaL_Buffer args;
 	luaL_buffinit(L, &args);
 	size_t i, n = lua_objlen(L, -1);
@@ -61,7 +76,7 @@ void spawn_param_args(struct spawn_params *p)
 	}
 	luaL_pushresult(&args);        /* ... argtab argstr */
 	lua_pushvalue(L, 1);           /* cmd opts ... argtab argstr cmd */
-	lua_replace(L, -2);            /* cmd opts ... argtab cmd argstr */
+	lua_insert(L, -2);             /* cmd opts ... argtab cmd argstr */
 	lua_concat(L, 2);              /* cmd opts ... argtab cmdline */
 	lua_replace(L, -2);            /* cmd opts ... cmdline */
 	p->cmdline = lua_tostring(L, -1);
@@ -99,53 +114,52 @@ void spawn_param_env(struct spawn_params *p)
 	p->environment = lua_tostring(L, -1);
 }
 
-/* _ opts ... */
-static int get_redirect(struct spawn_params *p, const char *stdname, HANDLE *ph)
+void spawn_param_redirect(struct spawn_params *p, const char *stdname, FILE *f)
 {
-	int ret;
-	lua_getfield(p->L, 2, stdname);
-	if ((ret = !lua_isnil(p->L, -1))) {
-		/* XXX checkuserdata is confusing here */
-		FILE **pf = checkuserdata(p->L, -1, LUA_FILEHANDLE);
-		*ph = get_handle(*pf);
+	HANDLE h = get_handle(f);
+	switch (stdname[3]) {
+	case 'i': p->si.hStdInput = h; break;
+	case 'o': p->si.hStdOutput = h; break;
+	case 'e': p->si.hStdError = h; break;
 	}
-	lua_pop(p->L, 1);
-	return ret;
+	p->si.dwFlags |= STARTF_USESTDHANDLES;
 }
 
-/* _ opts ... */
-void spawn_param_redirects(struct spawn_params *p)
-{
-	p->si.hStdInput  = GetStdHandle(STD_INPUT_HANDLE);
-	p->si.hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);
-	p->si.hStdError  = GetStdHandle(STD_ERROR_HANDLE);
-	if (get_redirect(p, "stdin",  &p->si.hStdInput)
-		| get_redirect(p, "stdout", &p->si.hStdOutput)
-		| get_redirect(p, "stderr", &p->si.hStdError))
-		p->si.dwFlags = STARTF_USESTDHANDLES;
-}
+struct process {
+    int status;
+    HANDLE hProcess;
+	DWORD dwProcessId;
+};
 
-int spawn_param_execute(struct spawn_params *p, struct process *proc)
+int spawn_param_execute(struct spawn_params *p)
 {
-	char *c = strdup(p->cmdline);
-	char *e = (char *)p->environment; // strdup(p->environment);
+	lua_State *L = p->L;
+	struct process *proc;
+	char *c, *e;
 	PROCESS_INFORMATION pi;
+	BOOL ret;
+
+	proc = lua_newuserdata(L, sizeof *proc);       /* cmd opts ... proc */
+	luaL_getmetatable(L, PROCESS_HANDLE);          /* cmd opts ... proc M */
+	lua_setmetatable(L, -2);                       /* cmd opts ... proc */
 	proc->status = -1;
+	c = strdup(p->cmdline);
+	e = (char *)p->environment; /* strdup(p->environment); */
 	/* XXX does CreateProcess modify its environment argument? */
-	int ret = CreateProcess(0, c, 0, 0, 0, 0, e, 0, &p->si, &pi);
-	if (e) free(e);
+	ret = CreateProcess(0, c, 0, 0, 0, 0, e, 0, &p->si, &pi);
+	/* if (e) free(e); */
 	free(c);
-	if (ret) {
-		proc->hProcess = pi.hProcess;
-		proc->dwProcessId = pi.dwProcessId;
-	}
-	return ret;
+	if (!ret)
+		return push_error(L);
+	proc->hProcess = pi.hProcess;
+	proc->dwProcessId = pi.dwProcessId;
+	return 1;
 }
 
 /* proc -- exitcode/nil error */
 int process_wait(lua_State *L)
 {
-	struct process *p = checkuserdata(L, 1, PROCESS_HANDLE);
+	struct process *p = luaL_checkudata(L, 1, PROCESS_HANDLE);
 	if (p->status == -1) {
 		DWORD exitcode;
 		if (WAIT_FAILED == WaitForSingleObject(p->hProcess, INFINITE)
@@ -160,7 +174,7 @@ int process_wait(lua_State *L)
 /* proc -- string */
 int process_tostring(lua_State *L)
 {
-	struct process *p = checkuserdata(L, 1, PROCESS_HANDLE);
+	struct process *p = luaL_checkudata(L, 1, PROCESS_HANDLE);
 	char buf[40];
 	lua_pushlstring(L, buf,
 		sprintf(buf, "process (%lu, %s)", (unsigned long)p->dwProcessId,

w32api/spawn.h

@@ -4,26 +4,16 @@
 
 #include <windows.h>
 
-struct spawn_params {
-	lua_State *L;
-	const char *cmdline;
-	const char *environment;
-	STARTUPINFO si;
-};
-
 #define PROCESS_HANDLE "process"
-struct process {
-    int status;
-    HANDLE hProcess;
-	DWORD dwProcessId;
-};
+struct process;
+struct spawn_params;
 
-void spawn_param_filename(struct spawn_params *p);
-void spawn_param_defaults(struct spawn_params *p);
+struct spawn_params *spawn_param_init(lua_State *L);
+void spawn_param_filename(struct spawn_params *p, const char *filename);
 void spawn_param_args(struct spawn_params *p);
 void spawn_param_env(struct spawn_params *p);
-void spawn_param_redirects(struct spawn_params *p);
-int spawn_param_execute(struct spawn_params *p, struct process *proc);
+void spawn_param_redirect(struct spawn_params *p, const char *stdname, FILE *f);
+int spawn_param_execute(struct spawn_params *p);
 
 int process_wait(lua_State *L);
 int process_tostring(lua_State *L);