0,0 → 1,501 |
/* |
** $Id: lua.c,v 1.203 2011/12/12 16:34:03 roberto Exp $ |
** Lua stand-alone interpreter |
** See Copyright Notice in lua.h |
*/ |
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#include <signal.h> |
#include <stdio.h> |
#include <stdlib.h> |
#include <string.h> |
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#define lua_c |
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#include "lua.h" |
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#include "lauxlib.h" |
#include "lualib.h" |
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#if !defined(LUA_PROMPT) |
#define LUA_PROMPT "> " |
#define LUA_PROMPT2 ">> " |
#endif |
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#if !defined(LUA_PROGNAME) |
#define LUA_PROGNAME "lua" |
#endif |
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#if !defined(LUA_MAXINPUT) |
#define LUA_MAXINPUT 512 |
#endif |
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#if !defined(LUA_INIT) |
#define LUA_INIT "LUA_INIT" |
#endif |
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#define LUA_INITVERSION \ |
LUA_INIT "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR |
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/* |
** 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 |
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/* |
** 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) |
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#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)) |
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#elif !defined(lua_readline) |
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#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; } |
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#endif |
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static lua_State *globalL = NULL; |
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static const char *progname = LUA_PROGNAME; |
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static void lstop (lua_State *L, lua_Debug *ar) { |
(void)ar; /* unused arg. */ |
lua_sethook(L, NULL, 0, 0); |
luaL_error(L, "interrupted!"); |
} |
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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); |
} |
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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); |
} |
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static void l_message (const char *pname, const char *msg) { |
if (pname) luai_writestringerror("%s: ", pname); |
luai_writestringerror("%s\n", msg); |
} |
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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; |
} |
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/* 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); |
} |
} |
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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; |
} |
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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; |
} |
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static void print_version (void) { |
luai_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT)); |
luai_writeline(); |
} |
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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; |
} |
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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); |
} |
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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); |
} |
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static int dolibrary (lua_State *L, const char *name) { |
int status; |
lua_pushglobaltable(L); |
lua_getfield(L, -1, "require"); |
lua_pushstring(L, name); |
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); |
} |
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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); |
lua_pop(L, 1); /* remove global */ |
return p; |
} |
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/* mark in error messages for incomplete statements */ |
#define EOFMARK "<eof>" |
#define marklen (sizeof(EOFMARK)/sizeof(char) - 1) |
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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... */ |
} |
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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; |
} |
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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; |
} |
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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; |
} |
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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); |
} |
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/* check that argument has no extra characters at the end */ |
#define noextrachars(x) {if ((x)[2] != '\0') return -1;} |
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/* 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 */ |
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#define num_has 4 /* number of 'has_*' */ |
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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; |
} |
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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; |
} |
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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); |
} |
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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; |
} |
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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; |
} |
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