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-rw-r--r--src/lua.c392
1 files changed, 392 insertions, 0 deletions
diff --git a/src/lua.c b/src/lua.c
new file mode 100644
index 0000000..3a46609
--- /dev/null
+++ b/src/lua.c
@@ -0,0 +1,392 @@
+/*
+** $Id: lua.c,v 1.160.1.2 2007/12/28 15:32:23 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"
+
+
+
+static lua_State *globalL = NULL;
+
+static const char *progname = LUA_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"
+ " -e stat execute string " LUA_QL("stat") "\n"
+ " -l name require library " LUA_QL("name") "\n"
+ " -i enter interactive mode after executing " LUA_QL("script") "\n"
+ " -v show version information\n"
+ " -- stop handling options\n"
+ " - execute stdin and stop handling options\n"
+ ,
+ progname);
+ fflush(stderr);
+}
+
+
+static void l_message (const char *pname, const char *msg) {
+ if (pname) fprintf(stderr, "%s: ", pname);
+ fprintf(stderr, "%s\n", msg);
+ fflush(stderr);
+}
+
+
+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 traceback (lua_State *L) {
+ if (!lua_isstring(L, 1)) /* 'message' not a string? */
+ return 1; /* keep it intact */
+ lua_getfield(L, LUA_GLOBALSINDEX, "debug");
+ if (!lua_istable(L, -1)) {
+ lua_pop(L, 1);
+ return 1;
+ }
+ lua_getfield(L, -1, "traceback");
+ if (!lua_isfunction(L, -1)) {
+ lua_pop(L, 2);
+ return 1;
+ }
+ lua_pushvalue(L, 1); /* pass error message */
+ lua_pushinteger(L, 2); /* skip this function and traceback */
+ lua_call(L, 2, 1); /* call debug.traceback */
+ return 1;
+}
+
+
+static int docall (lua_State *L, int narg, int clear) {
+ int status;
+ int base = lua_gettop(L) - narg; /* function index */
+ lua_pushcfunction(L, traceback); /* push 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 */
+ /* force a complete garbage collection in case of errors */
+ if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
+ return status;
+}
+
+
+static void print_version (void) {
+ l_message(NULL, LUA_RELEASE " " LUA_COPYRIGHT);
+}
+
+
+static int getargs (lua_State *L, char **argv, int n) {
+ int narg;
+ int i;
+ int argc = 0;
+ while (argv[argc]) argc++; /* count total number of arguments */
+ narg = argc - (n + 1); /* number of arguments to the script */
+ luaL_checkstack(L, narg + 3, "too many arguments to script");
+ for (i=n+1; i < argc; i++)
+ lua_pushstring(L, argv[i]);
+ lua_createtable(L, narg, n + 1);
+ for (i=0; i < argc; 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) {
+ lua_getglobal(L, "require");
+ lua_pushstring(L, name);
+ return report(L, docall(L, 1, 1));
+}
+
+
+static const char *get_prompt (lua_State *L, int firstline) {
+ const char *p;
+ lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2");
+ p = lua_tostring(L, -1);
+ if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);
+ lua_pop(L, 1); /* remove global */
+ return p;
+}
+
+
+static int incomplete (lua_State *L, int status) {
+ if (status == LUA_ERRSYNTAX) {
+ size_t lmsg;
+ const char *msg = lua_tolstring(L, -1, &lmsg);
+ const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1);
+ if (strstr(msg, LUA_QL("<eof>")) == tp) {
+ lua_pop(L, 1);
+ return 1;
+ }
+ }
+ return 0; /* else... */
+}
+
+
+static int pushline (lua_State *L, int firstline) {
+ char buffer[LUA_MAXINPUT];
+ char *b = buffer;
+ size_t l;
+ const char *prmt = get_prompt(L, firstline);
+ if (lua_readline(L, b, prmt) == 0)
+ return 0; /* no input */
+ l = strlen(b);
+ if (l > 0 && b[l-1] == '\n') /* line ends with newline? */
+ b[l-1] = '\0'; /* remove it */
+ if (firstline && b[0] == '=') /* first line starts with `=' ? */
+ lua_pushfstring(L, "return %s", b+1); /* change it to `return' */
+ else
+ lua_pushstring(L, b);
+ lua_freeline(L, b);
+ return 1;
+}
+
+
+static int loadline (lua_State *L) {
+ int status;
+ lua_settop(L, 0);
+ if (!pushline(L, 1))
+ return -1; /* no input */
+ 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 (!pushline(L, 0)) /* no more input? */
+ return -1;
+ lua_pushliteral(L, "\n"); /* add a new line... */
+ lua_insert(L, -2); /* ...between the two lines */
+ lua_concat(L, 3); /* join them */
+ }
+ lua_saveline(L, 1);
+ lua_remove(L, 1); /* remove line */
+ return status;
+}
+
+
+static void dotty (lua_State *L) {
+ int status;
+ const char *oldprogname = progname;
+ progname = NULL;
+ 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 " LUA_QL("print") " (%s)",
+ lua_tostring(L, -1)));
+ }
+ }
+ lua_settop(L, 0); /* clear stack */
+ fputs("\n", stdout);
+ fflush(stdout);
+ progname = oldprogname;
+}
+
+
+static int handle_script (lua_State *L, char **argv, int n) {
+ int status;
+ const char *fname;
+ int narg = getargs(L, argv, n); /* collect arguments */
+ lua_setglobal(L, "arg");
+ fname = argv[n];
+ if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0)
+ fname = NULL; /* stdin */
+ status = luaL_loadfile(L, fname);
+ lua_insert(L, -(narg+1));
+ if (status == 0)
+ status = docall(L, narg, 0);
+ else
+ lua_pop(L, narg);
+ return report(L, status);
+}
+
+
+/* check that argument has no extra characters at the end */
+#define notail(x) {if ((x)[2] != '\0') return -1;}
+
+
+static int collectargs (char **argv, int *pi, int *pv, int *pe) {
+ int i;
+ for (i = 1; argv[i] != NULL; i++) {
+ if (argv[i][0] != '-') /* not an option? */
+ return i;
+ switch (argv[i][1]) { /* option */
+ case '-':
+ notail(argv[i]);
+ return (argv[i+1] != NULL ? i+1 : 0);
+ case '\0':
+ return i;
+ case 'i':
+ notail(argv[i]);
+ *pi = 1; /* go through */
+ case 'v':
+ notail(argv[i]);
+ *pv = 1;
+ break;
+ case 'e':
+ *pe = 1; /* go through */
+ case 'l':
+ if (argv[i][2] == '\0') {
+ i++;
+ if (argv[i] == NULL) return -1;
+ }
+ break;
+ default: return -1; /* invalid option */
+ }
+ }
+ return 0;
+}
+
+
+static int runargs (lua_State *L, char **argv, int n) {
+ int i;
+ for (i = 1; i < n; i++) {
+ if (argv[i] == NULL) continue;
+ lua_assert(argv[i][0] == '-');
+ switch (argv[i][1]) { /* option */
+ case 'e': {
+ const char *chunk = argv[i] + 2;
+ if (*chunk == '\0') chunk = argv[++i];
+ lua_assert(chunk != NULL);
+ if (dostring(L, chunk, "=(command line)") != 0)
+ return 1;
+ break;
+ }
+ case 'l': {
+ const char *filename = argv[i] + 2;
+ if (*filename == '\0') filename = argv[++i];
+ lua_assert(filename != NULL);
+ if (dolibrary(L, filename))
+ return 1; /* stop if file fails */
+ break;
+ }
+ default: break;
+ }
+ }
+ 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);
+ char **argv = s->argv;
+ int script;
+ int has_i = 0, has_v = 0, has_e = 0;
+ globalL = L;
+ if (argv[0] && argv[0][0]) progname = argv[0];
+ lua_gc(L, LUA_GCSTOP, 0); /* stop collector during initialization */
+ luaL_openlibs(L); /* open libraries */
+ lua_gc(L, LUA_GCRESTART, 0);
+ s->status = handle_luainit(L);
+ if (s->status != 0) return 0;
+ script = collectargs(argv, &has_i, &has_v, &has_e);
+ if (script < 0) { /* invalid args? */
+ print_usage();
+ s->status = 1;
+ return 0;
+ }
+ if (has_v) print_version();
+ s->status = runargs(L, argv, (script > 0) ? script : s->argc);
+ if (s->status != 0) return 0;
+ if (script)
+ s->status = handle_script(L, argv, script);
+ if (s->status != 0) return 0;
+ if (has_i)
+ dotty(L);
+ else if (script == 0 && !has_e && !has_v) {
+ if (lua_stdin_is_tty()) {
+ print_version();
+ dotty(L);
+ }
+ else dofile(L, NULL); /* executes stdin as a file */
+ }
+ 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;
+}
+