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-rw-r--r--src/lua.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/src/lua.c b/src/lua.c
new file mode 100644
index 00000000..6a21a6ae
--- /dev/null
+++ b/src/lua.c
@@ -0,0 +1,388 @@
+/*
+** $Id: lua.c,v 1.133 2004/11/18 19:53:49 roberto Exp $
+** Lua stand-alone interpreter
+** See Copyright Notice in lua.h
+*/
+
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lua_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** generic extra include file
+*/
+#ifdef LUA_USERCONFIG
+#include LUA_USERCONFIG
+#endif
+
+
+
+
+static lua_State *globalL = NULL;
+
+static const char *progname = PROGNAME;
+
+
+
+static void lstop (lua_State *L, lua_Debug *ar) {
+ (void)ar; /* unused arg. */
+ lua_sethook(L, NULL, 0, 0);
+ luaL_error(L, "interrupted!");
+}
+
+
+static void laction (int i) {
+ signal(i, SIG_DFL); /* if another SIGINT happens before lstop,
+ terminate process (default action) */
+ lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);
+}
+
+
+static void print_usage (void) {
+ fprintf(stderr,
+ "usage: %s [options] [script [args]].\n"
+ "Available options are:\n"
+ " - execute stdin as a file\n"
+ " -e stat execute string `stat'\n"
+ " -i enter interactive mode after executing `script'\n"
+ " -l name load and run library `name'\n"
+ " -v show version information\n"
+ " -- stop handling options\n" ,
+ progname);
+}
+
+
+static void l_message (const char *pname, const char *msg) {
+ if (pname) fprintf(stderr, "%s: ", pname);
+ fprintf(stderr, "%s\n", msg);
+}
+
+
+static int report (lua_State *L, int status) {
+ if (status && !lua_isnil(L, -1)) {
+ const char *msg = lua_tostring(L, -1);
+ if (msg == NULL) msg = "(error object is not a string)";
+ l_message(progname, msg);
+ lua_pop(L, 1);
+ }
+ return status;
+}
+
+
+static int docall (lua_State *L, int narg, int clear) {
+ int status;
+ int base = lua_gettop(L) - narg; /* function index */
+ lua_pushliteral(L, "_TRACEBACK");
+ lua_rawget(L, LUA_GLOBALSINDEX); /* get traceback function */
+ lua_insert(L, base); /* put it under chunk and args */
+ signal(SIGINT, laction);
+ status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base);
+ signal(SIGINT, SIG_DFL);
+ lua_remove(L, base); /* remove traceback function */
+ return status;
+}
+
+
+static void print_version (void) {
+ l_message(NULL, LUA_VERSION " " LUA_COPYRIGHT);
+}
+
+
+static int getargs (lua_State *L, char *argv[], int n) {
+ int i, narg;
+ for (i=n+1; argv[i]; i++) {
+ luaL_checkstack(L, 1, "too many arguments to script");
+ lua_pushstring(L, argv[i]);
+ }
+ narg = i-(n+1); /* number of arguments to the script (not to `lua.c') */
+ lua_newtable(L);
+ for (i=0; argv[i]; i++) {
+ lua_pushstring(L, argv[i]);
+ lua_rawseti(L, -2, i - n);
+ }
+ return narg;
+}
+
+
+static int dofile (lua_State *L, const char *name) {
+ int status = luaL_loadfile(L, name) || docall(L, 0, 1);
+ return report(L, status);
+}
+
+
+static int dostring (lua_State *L, const char *s, const char *name) {
+ int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1);
+ return report(L, status);
+}
+
+
+static int dolibrary (lua_State *L, const char *name) {
+ luaL_getfield(L, LUA_GLOBALSINDEX, "package.path");
+ if (!lua_isstring(L, -1)) {
+ l_message(progname, "`package.path' must be a string");
+ return 1;
+ }
+ name = luaL_searchpath(L, name, lua_tostring(L, -1));
+ if (name == NULL) return report(L, 1);
+ else return dofile(L, name);
+}
+
+
+
+/*
+** this macro defines a function to show the prompt and reads the
+** next line for manual input
+*/
+#ifndef lua_readline
+#define lua_readline(L,prompt) readline(L,prompt)
+
+/* maximum length of an input line */
+#ifndef MAXINPUT
+#define MAXINPUT 512
+#endif
+
+
+static int readline (lua_State *L, const char *prompt) {
+ static char buffer[MAXINPUT];
+ if (prompt) {
+ fputs(prompt, stdout);
+ fflush(stdout);
+ }
+ if (fgets(buffer, sizeof(buffer), stdin) == NULL)
+ return 0; /* read fails */
+ else {
+ lua_pushstring(L, buffer);
+ return 1;
+ }
+}
+
+#endif
+
+
+static const char *get_prompt (lua_State *L, int firstline) {
+ const char *p = NULL;
+ lua_pushstring(L, firstline ? "_PROMPT" : "_PROMPT2");
+ lua_rawget(L, LUA_GLOBALSINDEX);
+ p = lua_tostring(L, -1);
+ if (p == NULL) p = (firstline ? PROMPT : PROMPT2);
+ lua_pop(L, 1); /* remove global */
+ return p;
+}
+
+
+static int incomplete (lua_State *L, int status) {
+ if (status == LUA_ERRSYNTAX &&
+ strstr(lua_tostring(L, -1), "near `<eof>'") != NULL) {
+ lua_pop(L, 1);
+ return 1;
+ }
+ else
+ return 0;
+}
+
+
+static int loadline (lua_State *L) {
+ int status;
+ lua_settop(L, 0);
+ if (lua_readline(L, get_prompt(L, 1)) == 0) /* no input? */
+ return -1;
+ if (lua_tostring(L, -1)[0] == '=') { /* line starts with `=' ? */
+ lua_pushfstring(L, "return %s", lua_tostring(L, -1)+1);/* `=' -> `return' */
+ lua_remove(L, -2); /* remove original line */
+ }
+ for (;;) { /* repeat until gets a complete line */
+ status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
+ if (!incomplete(L, status)) break; /* cannot try to add lines? */
+ if (lua_readline(L, get_prompt(L, 0)) == 0) /* no more input? */
+ return -1;
+ lua_concat(L, lua_gettop(L)); /* join lines */
+ }
+ lua_saveline(L, lua_tostring(L, 1));
+ lua_remove(L, 1); /* remove line */
+ return status;
+}
+
+
+static void dotty (lua_State *L) {
+ int status;
+ const char *oldprogname = progname;
+ progname = NULL;
+ print_version();
+ while ((status = loadline(L)) != -1) {
+ if (status == 0) status = docall(L, 0, 0);
+ report(L, status);
+ if (status == 0 && lua_gettop(L) > 0) { /* any result to print? */
+ lua_getglobal(L, "print");
+ lua_insert(L, 1);
+ if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
+ l_message(progname, lua_pushfstring(L, "error calling `print' (%s)",
+ lua_tostring(L, -1)));
+ }
+ }
+ lua_settop(L, 0); /* clear stack */
+ fputs("\n", stdout);
+ progname = oldprogname;
+}
+
+
+static int checkvar (lua_State *L) {
+ const char *name = lua_tostring(L, 2);
+ if (name)
+ luaL_error(L, "attempt to access undefined variable `%s'", name);
+ return 0;
+}
+
+
+#define clearinteractive(i) (*i &= 2)
+
+static int handle_argv (lua_State *L, char *argv[], int *interactive) {
+ if (argv[1] == NULL) { /* no arguments? */
+ *interactive = 0;
+ if (stdin_is_tty())
+ dotty(L);
+ else
+ dofile(L, NULL); /* executes stdin as a file */
+ }
+ else { /* other arguments; loop over them */
+ int i;
+ for (i = 1; argv[i] != NULL; i++) {
+ if (argv[i][0] != '-') break; /* not an option? */
+ switch (argv[i][1]) { /* option */
+ case '-': { /* `--' */
+ if (argv[i][2] != '\0') {
+ print_usage();
+ return 1;
+ }
+ i++; /* skip this argument */
+ goto endloop; /* stop handling arguments */
+ }
+ case '\0': {
+ clearinteractive(interactive);
+ dofile(L, NULL); /* executes stdin as a file */
+ break;
+ }
+ case 'i': {
+ *interactive = 2; /* force interactive mode after arguments */
+ break;
+ }
+ case 'v': {
+ clearinteractive(interactive);
+ print_version();
+ break;
+ }
+ case 'w': {
+ if (lua_getmetatable(L, LUA_GLOBALSINDEX)) {
+ lua_pushcfunction(L, checkvar);
+ lua_setfield(L, -2, "__index");
+ }
+ break;
+ }
+ case 'e': {
+ const char *chunk = argv[i] + 2;
+ clearinteractive(interactive);
+ if (*chunk == '\0') chunk = argv[++i];
+ if (chunk == NULL) {
+ print_usage();
+ return 1;
+ }
+ if (dostring(L, chunk, "=(command line)") != 0)
+ return 1;
+ break;
+ }
+ case 'l': {
+ const char *filename = argv[i] + 2;
+ if (*filename == '\0') filename = argv[++i];
+ if (filename == NULL) {
+ print_usage();
+ return 1;
+ }
+ if (dolibrary(L, filename))
+ return 1; /* stop if file fails */
+ break;
+ }
+ default: {
+ clearinteractive(interactive);
+ print_usage();
+ return 1;
+ }
+ }
+ } endloop:
+ if (argv[i] != NULL) {
+ const char *filename = argv[i];
+ int narg = getargs(L, argv, i); /* collect arguments */
+ int status;
+ lua_setglobal(L, "arg");
+ clearinteractive(interactive);
+ status = luaL_loadfile(L, filename);
+ lua_insert(L, -(narg+1));
+ if (status == 0)
+ status = docall(L, narg, 0);
+ else
+ lua_pop(L, narg);
+ return report(L, status);
+ }
+ }
+ return 0;
+}
+
+
+static int handle_luainit (lua_State *L) {
+ const char *init = getenv("LUA_INIT");
+ if (init == NULL) return 0; /* status OK */
+ else if (init[0] == '@')
+ return dofile(L, init+1);
+ else
+ return dostring(L, init, "=LUA_INIT");
+}
+
+
+struct Smain {
+ int argc;
+ char **argv;
+ int status;
+};
+
+
+static int pmain (lua_State *L) {
+ struct Smain *s = (struct Smain *)lua_touserdata(L, 1);
+ int status;
+ int interactive = 1;
+ if (s->argv[0] && s->argv[0][0]) progname = s->argv[0];
+ globalL = L;
+ lua_userinit(L); /* open libraries */
+ status = handle_luainit(L);
+ if (status == 0) {
+ status = handle_argv(L, s->argv, &interactive);
+ if (status == 0 && interactive) dotty(L);
+ }
+ s->status = status;
+ return 0;
+}
+
+
+int main (int argc, char *argv[]) {
+ int status;
+ struct Smain s;
+ lua_State *L = lua_open(); /* create state */
+ if (L == NULL) {
+ l_message(argv[0], "cannot create state: not enough memory");
+ return EXIT_FAILURE;
+ }
+ s.argc = argc;
+ s.argv = argv;
+ status = lua_cpcall(L, &pmain, &s);
+ report(L, status);
+ lua_close(L);
+ return (status || s.status) ? EXIT_FAILURE : EXIT_SUCCESS;
+}
+
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