Mercurial > mm7
diff lib/lua/lua-5.2.2/lua.c @ 1866:41cc4dd3c122
Lua 5.2.2 added.
author | Nomad |
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date | Wed, 16 Oct 2013 13:34:26 +0200 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/lib/lua/lua-5.2.2/lua.c Wed Oct 16 13:34:26 2013 +0200 @@ -0,0 +1,497 @@ +/* +** $Id: lua.c,v 1.206 2012/09/29 20:07:06 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" + + +#if !defined(LUA_PROMPT) +#define LUA_PROMPT "> " +#define LUA_PROMPT2 ">> " +#endif + +#if !defined(LUA_PROGNAME) +#define LUA_PROGNAME "lua" +#endif + +#if !defined(LUA_MAXINPUT) +#define LUA_MAXINPUT 512 +#endif + +#if !defined(LUA_INIT) +#define LUA_INIT "LUA_INIT" +#endif + +#define LUA_INITVERSION \ + LUA_INIT "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR + + +/* +** lua_stdin_is_tty detects whether the standard input is a 'tty' (that +** is, whether we're running lua interactively). +*/ +#if defined(LUA_USE_ISATTY) +#include <unistd.h> +#define lua_stdin_is_tty() isatty(0) +#elif defined(LUA_WIN) +#include <io.h> +#include <stdio.h> +#define lua_stdin_is_tty() _isatty(_fileno(stdin)) +#else +#define lua_stdin_is_tty() 1 /* assume stdin is a tty */ +#endif + + +/* +** lua_readline defines how to show a prompt and then read a line from +** the standard input. +** lua_saveline defines how to "save" a read line in a "history". +** lua_freeline defines how to free a line read by lua_readline. +*/ +#if defined(LUA_USE_READLINE) + +#include <stdio.h> +#include <readline/readline.h> +#include <readline/history.h> +#define lua_readline(L,b,p) ((void)L, ((b)=readline(p)) != NULL) +#define lua_saveline(L,idx) \ + if (lua_rawlen(L,idx) > 0) /* non-empty line? */ \ + add_history(lua_tostring(L, idx)); /* add it to history */ +#define lua_freeline(L,b) ((void)L, free(b)) + +#elif !defined(lua_readline) + +#define lua_readline(L,b,p) \ + ((void)L, fputs(p, stdout), fflush(stdout), /* show prompt */ \ + fgets(b, LUA_MAXINPUT, stdin) != NULL) /* get line */ +#define lua_saveline(L,idx) { (void)L; (void)idx; } +#define lua_freeline(L,b) { (void)L; (void)b; } + +#endif + + + + +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 (const char *badoption) { + luai_writestringerror("%s: ", progname); + if (badoption[1] == 'e' || badoption[1] == 'l') + luai_writestringerror("'%s' needs argument\n", badoption); + else + luai_writestringerror("unrecognized option '%s'\n", badoption); + luai_writestringerror( + "usage: %s [options] [script [args]]\n" + "Available options are:\n" + " -e stat execute string " LUA_QL("stat") "\n" + " -i enter interactive mode after executing " LUA_QL("script") "\n" + " -l name require library " LUA_QL("name") "\n" + " -v show version information\n" + " -E ignore environment variables\n" + " -- stop handling options\n" + " - stop handling options and execute stdin\n" + , + progname); +} + + +static void l_message (const char *pname, const char *msg) { + if (pname) luai_writestringerror("%s: ", pname); + luai_writestringerror("%s\n", msg); +} + + +static int report (lua_State *L, int status) { + if (status != LUA_OK && !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); + /* force a complete garbage collection in case of errors */ + lua_gc(L, LUA_GCCOLLECT, 0); + } + return status; +} + + +/* the next function is called unprotected, so it must avoid errors */ +static void finalreport (lua_State *L, int status) { + if (status != LUA_OK) { + const char *msg = (lua_type(L, -1) == LUA_TSTRING) ? lua_tostring(L, -1) + : NULL; + if (msg == NULL) msg = "(error object is not a string)"; + l_message(progname, msg); + lua_pop(L, 1); + } +} + + +static int traceback (lua_State *L) { + const char *msg = lua_tostring(L, 1); + if (msg) + luaL_traceback(L, L, msg, 1); + else if (!lua_isnoneornil(L, 1)) { /* is there an error object? */ + if (!luaL_callmeta(L, 1, "__tostring")) /* try its 'tostring' metamethod */ + lua_pushliteral(L, "(no error message)"); + } + return 1; +} + + +static int docall (lua_State *L, int narg, int nres) { + 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 */ + globalL = L; /* to be available to 'laction' */ + signal(SIGINT, laction); + status = lua_pcall(L, narg, nres, base); + signal(SIGINT, SIG_DFL); + lua_remove(L, base); /* remove traceback function */ + return status; +} + + +static void print_version (void) { + luai_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT)); + luai_writeline(); +} + + +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); + if (status == LUA_OK) status = docall(L, 0, 0); + 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); + if (status == LUA_OK) status = docall(L, 0, 0); + return report(L, status); +} + + +static int dolibrary (lua_State *L, const char *name) { + int status; + lua_getglobal(L, "require"); + lua_pushstring(L, name); + status = docall(L, 1, 1); /* call 'require(name)' */ + if (status == LUA_OK) + lua_setglobal(L, name); /* global[name] = require return */ + return report(L, status); +} + + +static const char *get_prompt (lua_State *L, int firstline) { + const char *p; + lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2"); + p = lua_tostring(L, -1); + if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2); + return p; +} + +/* mark in error messages for incomplete statements */ +#define EOFMARK "<eof>" +#define marklen (sizeof(EOFMARK)/sizeof(char) - 1) + +static int incomplete (lua_State *L, int status) { + if (status == LUA_ERRSYNTAX) { + size_t lmsg; + const char *msg = lua_tolstring(L, -1, &lmsg); + if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) { + 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); + int readstatus = lua_readline(L, b, prmt); + lua_pop(L, 1); /* remove result from 'get_prompt' */ + if (readstatus == 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 */ + size_t l; + const char *line = lua_tolstring(L, 1, &l); + status = luaL_loadbuffer(L, line, l, "=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 == LUA_OK) status = docall(L, 0, LUA_MULTRET); + report(L, status); + if (status == LUA_OK && lua_gettop(L) > 0) { /* any result to print? */ + luaL_checkstack(L, LUA_MINSTACK, "too many results to print"); + lua_getglobal(L, "print"); + lua_insert(L, 1); + if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != LUA_OK) + l_message(progname, lua_pushfstring(L, + "error calling " LUA_QL("print") " (%s)", + lua_tostring(L, -1))); + } + } + lua_settop(L, 0); /* clear stack */ + luai_writeline(); + 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 == LUA_OK) + status = docall(L, narg, LUA_MULTRET); + else + lua_pop(L, narg); + return report(L, status); +} + + +/* check that argument has no extra characters at the end */ +#define noextrachars(x) {if ((x)[2] != '\0') return -1;} + + +/* indices of various argument indicators in array args */ +#define has_i 0 /* -i */ +#define has_v 1 /* -v */ +#define has_e 2 /* -e */ +#define has_E 3 /* -E */ + +#define num_has 4 /* number of 'has_*' */ + + +static int collectargs (char **argv, int *args) { + int i; + for (i = 1; argv[i] != NULL; i++) { + if (argv[i][0] != '-') /* not an option? */ + return i; + switch (argv[i][1]) { /* option */ + case '-': + noextrachars(argv[i]); + return (argv[i+1] != NULL ? i+1 : 0); + case '\0': + return i; + case 'E': + args[has_E] = 1; + break; + case 'i': + noextrachars(argv[i]); + args[has_i] = 1; /* go through */ + case 'v': + noextrachars(argv[i]); + args[has_v] = 1; + break; + case 'e': + args[has_e] = 1; /* go through */ + case 'l': /* both options need an argument */ + if (argv[i][2] == '\0') { /* no concatenated argument? */ + i++; /* try next 'argv' */ + if (argv[i] == NULL || argv[i][0] == '-') + return -(i - 1); /* no next argument or it is another option */ + } + break; + default: /* invalid option; return its index... */ + return -i; /* ...as a negative value */ + } + } + return 0; +} + + +static int runargs (lua_State *L, char **argv, int n) { + int i; + for (i = 1; i < n; i++) { + 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)") != LUA_OK) + return 0; + break; + } + case 'l': { + const char *filename = argv[i] + 2; + if (*filename == '\0') filename = argv[++i]; + lua_assert(filename != NULL); + if (dolibrary(L, filename) != LUA_OK) + return 0; /* stop if file fails */ + break; + } + default: break; + } + } + return 1; +} + + +static int handle_luainit (lua_State *L) { + const char *name = "=" LUA_INITVERSION; + const char *init = getenv(name + 1); + if (init == NULL) { + name = "=" LUA_INIT; + init = getenv(name + 1); /* try alternative name */ + } + if (init == NULL) return LUA_OK; + else if (init[0] == '@') + return dofile(L, init+1); + else + return dostring(L, init, name); +} + + +static int pmain (lua_State *L) { + int argc = (int)lua_tointeger(L, 1); + char **argv = (char **)lua_touserdata(L, 2); + int script; + int args[num_has]; + args[has_i] = args[has_v] = args[has_e] = args[has_E] = 0; + if (argv[0] && argv[0][0]) progname = argv[0]; + script = collectargs(argv, args); + if (script < 0) { /* invalid arg? */ + print_usage(argv[-script]); + return 0; + } + if (args[has_v]) print_version(); + if (args[has_E]) { /* option '-E'? */ + lua_pushboolean(L, 1); /* signal for libraries to ignore env. vars. */ + lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV"); + } + /* open standard libraries */ + luaL_checkversion(L); + lua_gc(L, LUA_GCSTOP, 0); /* stop collector during initialization */ + luaL_openlibs(L); /* open libraries */ + lua_gc(L, LUA_GCRESTART, 0); + if (!args[has_E] && handle_luainit(L) != LUA_OK) + return 0; /* error running LUA_INIT */ + /* execute arguments -e and -l */ + if (!runargs(L, argv, (script > 0) ? script : argc)) return 0; + /* execute main script (if there is one) */ + if (script && handle_script(L, argv, script) != LUA_OK) return 0; + if (args[has_i]) /* -i option? */ + dotty(L); + else if (script == 0 && !args[has_e] && !args[has_v]) { /* no arguments? */ + if (lua_stdin_is_tty()) { + print_version(); + dotty(L); + } + else dofile(L, NULL); /* executes stdin as a file */ + } + lua_pushboolean(L, 1); /* signal no errors */ + return 1; +} + + +int main (int argc, char **argv) { + int status, result; + lua_State *L = luaL_newstate(); /* create state */ + if (L == NULL) { + l_message(argv[0], "cannot create state: not enough memory"); + return EXIT_FAILURE; + } + /* call 'pmain' in protected mode */ + lua_pushcfunction(L, &pmain); + lua_pushinteger(L, argc); /* 1st argument */ + lua_pushlightuserdata(L, argv); /* 2nd argument */ + status = lua_pcall(L, 2, 1, 0); + result = lua_toboolean(L, -1); /* get result */ + finalreport(L, status); + lua_close(L); + return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE; +} +