diff options
Diffstat (limited to 'lua/lua.c')
| -rw-r--r-- | lua/lua.c | 317 |
1 files changed, 213 insertions, 104 deletions
@@ -1,5 +1,5 @@ /* -** $Id: lua.c,v 1.160.1.2 2007/12/28 15:32:23 roberto Exp $ +** $Id: lua.c,v 1.203 2011/12/12 16:34:03 roberto Exp $ ** Lua stand-alone interpreter ** See Copyright Notice in lua.h */ @@ -18,6 +18,72 @@ #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; @@ -39,77 +105,87 @@ static void laction (int i) { } -static void print_usage (void) { - fprintf(stderr, - "usage: %s [options] [script [args]].\n" +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" - " -l name require library " LUA_QL("name") "\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" - " - execute stdin and stop handling options\n" + " - stop handling options and execute stdin\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); + if (pname) luai_writestringerror("%s: ", pname); + luai_writestringerror("%s\n", msg); } static int report (lua_State *L, int status) { - if (status && !lua_isnil(L, -1)) { + 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; } -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)) { +/* 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); - return 1; } - lua_getfield(L, -1, "traceback"); - if (!lua_isfunction(L, -1)) { - lua_pop(L, 2); - return 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)"); } - 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) { +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, (clear ? 0 : LUA_MULTRET), base); + status = lua_pcall(L, narg, nres, 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); + luai_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT)); + luai_writeline(); } @@ -132,40 +208,53 @@ static int getargs (lua_State *L, char **argv, int n) { static int dofile (lua_State *L, const char *name) { - int status = luaL_loadfile(L, name) || docall(L, 0, 1); + 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) || docall(L, 0, 1); + 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) { - lua_getglobal(L, "require"); + int status; + lua_pushglobaltable(L); + lua_getfield(L, -1, "require"); lua_pushstring(L, name); - return report(L, docall(L, 1, 1)); + status = docall(L, 1, 1); + if (status == LUA_OK) { + lua_setfield(L, -2, name); /* global[name] = require return */ + lua_pop(L, 1); /* remove global table */ + } + else + lua_remove(L, -2); /* remove global table (below error msg.) */ + return report(L, status); } static const char *get_prompt (lua_State *L, int firstline) { const char *p; - lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2"); + lua_getglobal(L, 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; } +/* 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); - const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1); - if (strstr(msg, LUA_QL("<eof>")) == tp) { + if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) { lua_pop(L, 1); return 1; } @@ -199,7 +288,9 @@ static int loadline (lua_State *L) { 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"); + 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; @@ -218,20 +309,20 @@ static void dotty (lua_State *L) { const char *oldprogname = progname; progname = NULL; while ((status = loadline(L)) != -1) { - if (status == 0) status = docall(L, 0, 0); + if (status == LUA_OK) status = docall(L, 0, LUA_MULTRET); report(L, status); - if (status == 0 && lua_gettop(L) > 0) { /* any result to print? */ + 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) != 0) + 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 */ - fputs("\n", stdout); - fflush(stdout); + luai_writeline(); progname = oldprogname; } @@ -242,49 +333,63 @@ static int handle_script (lua_State *L, char **argv, int n) { int narg = getargs(L, argv, n); /* collect arguments */ lua_setglobal(L, "arg"); fname = argv[n]; - if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0) + 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); + if (status == LUA_OK) + status = docall(L, narg, LUA_MULTRET); else - lua_pop(L, narg); + 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;} +#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 *pi, int *pv, int *pe) { + +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 '-': - notail(argv[i]); + noextrachars(argv[i]); return (argv[i+1] != NULL ? i+1 : 0); case '\0': return i; + case 'E': + args[has_E] = 1; + break; case 'i': - notail(argv[i]); - *pi = 1; /* go through */ + noextrachars(argv[i]); + args[has_i] = 1; /* go through */ case 'v': - notail(argv[i]); - *pv = 1; + noextrachars(argv[i]); + args[has_v] = 1; break; case 'e': - *pe = 1; /* go through */ - case 'l': - if (argv[i][2] == '\0') { - i++; - if (argv[i] == NULL) return -1; + 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: return -1; /* invalid option */ + default: /* invalid option; return its index... */ + return -i; /* ...as a negative value */ } } return 0; @@ -294,99 +399,103 @@ static int collectargs (char **argv, int *pi, int *pv, int *pe) { 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; + 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)) - return 1; /* stop if file fails */ + if (dolibrary(L, filename) != LUA_OK) + return 0; /* stop if file fails */ break; } default: break; } } - return 0; + return 1; } static int handle_luainit (lua_State *L) { - const char *init = getenv(LUA_INIT); - if (init == NULL) return 0; /* status OK */ + 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, "=" LUA_INIT); + return dostring(L, init, name); } -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 argc = (int)lua_tointeger(L, 1); + char **argv = (char **)lua_touserdata(L, 2); int script; - int has_i = 0, has_v = 0, has_e = 0; - globalL = L; + 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); - 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) + 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 && !has_e && !has_v) { + 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 */ } - return 0; + lua_pushboolean(L, 1); /* signal no errors */ + return 1; } int main (int argc, char **argv) { - int status; - struct Smain s; - lua_State *L = lua_open(); /* create state */ + 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; } - s.argc = argc; - s.argv = argv; - status = lua_cpcall(L, &pmain, &s); - report(L, status); + /* 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 (status || s.status) ? EXIT_FAILURE : EXIT_SUCCESS; + return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE; } |