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authorJeffrey Armstrong <jeff@approximatrix.com>2020-09-28 20:25:16 -0400
committerJeffrey Armstrong <jeff@approximatrix.com>2020-09-28 20:25:16 -0400
commit334ee3f66a7aad17c9865bd9952b0c501b97721a (patch)
tree0ee71269e8c482e6a2df9cbb37dbe15302136799 /src/lua.c
downloadrainbow-lua-334ee3f66a7aad17c9865bd9952b0c501b97721a.zip
rainbow-lua-334ee3f66a7aad17c9865bd9952b0c501b97721a.tar.gz
Initial import based on Lua 5.3.5
Diffstat (limited to 'src/lua.c')
-rw-r--r--src/lua.c612
1 files changed, 612 insertions, 0 deletions
diff --git a/src/lua.c b/src/lua.c
new file mode 100644
index 0000000..ca5b298
--- /dev/null
+++ b/src/lua.c
@@ -0,0 +1,612 @@
+/*
+** $Id: lua.c,v 1.230.1.1 2017/04/19 17:29:57 roberto Exp $
+** Lua stand-alone interpreter
+** See Copyright Notice in lua.h
+*/
+
+#define lua_c
+
+#include "lprefix.h"
+
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#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_VAR)
+#define LUA_INIT_VAR "LUA_INIT"
+#endif
+
+#define LUA_INITVARVERSION LUA_INIT_VAR LUA_VERSUFFIX
+
+
+/*
+** lua_stdin_is_tty detects whether the standard input is a 'tty' (that
+** is, whether we're running lua interactively).
+*/
+#if !defined(lua_stdin_is_tty) /* { */
+
+#if defined(LUA_USE_POSIX) /* { */
+
+#include <unistd.h>
+#define lua_stdin_is_tty() isatty(0)
+
+#elif defined(LUA_USE_WINDOWS) /* }{ */
+
+#include <io.h>
+#include <windows.h>
+
+#define lua_stdin_is_tty() _isatty(_fileno(stdin))
+
+#else /* }{ */
+
+/* ISO C definition */
+#define lua_stdin_is_tty() 1 /* assume stdin is a tty */
+
+#endif /* } */
+
+#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_readline) /* { */
+
+#if defined(LUA_USE_READLINE) /* { */
+
+#include <readline/readline.h>
+#include <readline/history.h>
+#define lua_readline(L,b,p) ((void)L, ((b)=readline(p)) != NULL)
+#define lua_saveline(L,line) ((void)L, add_history(line))
+#define lua_freeline(L,b) ((void)L, free(b))
+
+#else /* }{ */
+
+#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,line) { (void)L; (void)line; }
+#define lua_freeline(L,b) { (void)L; (void)b; }
+
+#endif /* } */
+
+#endif /* } */
+
+
+
+
+static lua_State *globalL = NULL;
+
+static const char *progname = LUA_PROGNAME;
+
+
+/*
+** Hook set by signal function to stop the interpreter.
+*/
+static void lstop (lua_State *L, lua_Debug *ar) {
+ (void)ar; /* unused arg. */
+ lua_sethook(L, NULL, 0, 0); /* reset hook */
+ luaL_error(L, "interrupted!");
+}
+
+
+/*
+** Function to be called at a C signal. Because a C signal cannot
+** just change a Lua state (as there is no proper synchronization),
+** this function only sets a hook that, when called, will stop the
+** interpreter.
+*/
+static void laction (int i) {
+ signal(i, SIG_DFL); /* if another SIGINT happens, terminate process */
+ lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);
+}
+
+
+static void print_usage (const char *badoption) {
+ lua_writestringerror("%s: ", progname);
+ if (badoption[1] == 'e' || badoption[1] == 'l')
+ lua_writestringerror("'%s' needs argument\n", badoption);
+ else
+ lua_writestringerror("unrecognized option '%s'\n", badoption);
+ lua_writestringerror(
+ "usage: %s [options] [script [args]]\n"
+ "Available options are:\n"
+ " -e stat execute string 'stat'\n"
+ " -i enter interactive mode after executing 'script'\n"
+ " -l name require library 'name' into global 'name'\n"
+ " -v show version information\n"
+ " -E ignore environment variables\n"
+ " -- stop handling options\n"
+ " - stop handling options and execute stdin\n"
+ ,
+ progname);
+}
+
+
+/*
+** Prints an error message, adding the program name in front of it
+** (if present)
+*/
+static void l_message (const char *pname, const char *msg) {
+ if (pname) lua_writestringerror("%s: ", pname);
+ lua_writestringerror("%s\n", msg);
+}
+
+
+/*
+** Check whether 'status' is not OK and, if so, prints the error
+** message on the top of the stack. It assumes that the error object
+** is a string, as it was either generated by Lua or by 'msghandler'.
+*/
+static int report (lua_State *L, int status) {
+ if (status != LUA_OK) {
+ const char *msg = lua_tostring(L, -1);
+ l_message(progname, msg);
+ lua_pop(L, 1); /* remove message */
+ }
+ return status;
+}
+
+
+/*
+** Message handler used to run all chunks
+*/
+static int msghandler (lua_State *L) {
+ const char *msg = lua_tostring(L, 1);
+ if (msg == NULL) { /* is error object not a string? */
+ if (luaL_callmeta(L, 1, "__tostring") && /* does it have a metamethod */
+ lua_type(L, -1) == LUA_TSTRING) /* that produces a string? */
+ return 1; /* that is the message */
+ else
+ msg = lua_pushfstring(L, "(error object is a %s value)",
+ luaL_typename(L, 1));
+ }
+ luaL_traceback(L, L, msg, 1); /* append a standard traceback */
+ return 1; /* return the traceback */
+}
+
+
+/*
+** Interface to 'lua_pcall', which sets appropriate message function
+** and C-signal handler. Used to run all chunks.
+*/
+static int docall (lua_State *L, int narg, int nres) {
+ int status;
+ int base = lua_gettop(L) - narg; /* function index */
+ lua_pushcfunction(L, msghandler); /* push message handler */
+ lua_insert(L, base); /* put it under function and args */
+ globalL = L; /* to be available to 'laction' */
+ signal(SIGINT, laction); /* set C-signal handler */
+ status = lua_pcall(L, narg, nres, base);
+ signal(SIGINT, SIG_DFL); /* reset C-signal handler */
+ lua_remove(L, base); /* remove message handler from the stack */
+ return status;
+}
+
+
+static void print_version (void) {
+ lua_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));
+ lua_writeline();
+}
+
+
+/*
+** Create the 'arg' table, which stores all arguments from the
+** command line ('argv'). It should be aligned so that, at index 0,
+** it has 'argv[script]', which is the script name. The arguments
+** to the script (everything after 'script') go to positive indices;
+** other arguments (before the script name) go to negative indices.
+** If there is no script name, assume interpreter's name as base.
+*/
+static void createargtable (lua_State *L, char **argv, int argc, int script) {
+ int i, narg;
+ if (script == argc) script = 0; /* no script name? */
+ narg = argc - (script + 1); /* number of positive indices */
+ lua_createtable(L, narg, script + 1);
+ for (i = 0; i < argc; i++) {
+ lua_pushstring(L, argv[i]);
+ lua_rawseti(L, -2, i - script);
+ }
+ lua_setglobal(L, "arg");
+}
+
+
+static int dochunk (lua_State *L, int status) {
+ if (status == LUA_OK) status = docall(L, 0, 0);
+ return report(L, status);
+}
+
+
+static int dofile (lua_State *L, const char *name) {
+ return dochunk(L, luaL_loadfile(L, name));
+}
+
+
+static int dostring (lua_State *L, const char *s, const char *name) {
+ return dochunk(L, luaL_loadbuffer(L, s, strlen(s), name));
+}
+
+
+/*
+** Calls 'require(name)' and stores the result in a global variable
+** with the given name.
+*/
+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);
+}
+
+
+/*
+** Returns the string to be used as a prompt by the interpreter.
+*/
+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)
+
+
+/*
+** Check whether 'status' signals a syntax error and the error
+** message at the top of the stack ends with the above mark for
+** incomplete statements.
+*/
+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... */
+}
+
+
+/*
+** Prompt the user, read a line, and push it into the Lua stack.
+*/
+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);
+ if (readstatus == 0)
+ return 0; /* no input (prompt will be popped by caller) */
+ lua_pop(L, 1); /* remove prompt */
+ l = strlen(b);
+ if (l > 0 && b[l-1] == '\n') /* line ends with newline? */
+ b[--l] = '\0'; /* remove it */
+ if (firstline && b[0] == '=') /* for compatibility with 5.2, ... */
+ lua_pushfstring(L, "return %s", b + 1); /* change '=' to 'return' */
+ else
+ lua_pushlstring(L, b, l);
+ lua_freeline(L, b);
+ return 1;
+}
+
+
+/*
+** Try to compile line on the stack as 'return <line>;'; on return, stack
+** has either compiled chunk or original line (if compilation failed).
+*/
+static int addreturn (lua_State *L) {
+ const char *line = lua_tostring(L, -1); /* original line */
+ const char *retline = lua_pushfstring(L, "return %s;", line);
+ int status = luaL_loadbuffer(L, retline, strlen(retline), "=stdin");
+ if (status == LUA_OK) {
+ lua_remove(L, -2); /* remove modified line */
+ if (line[0] != '\0') /* non empty? */
+ lua_saveline(L, line); /* keep history */
+ }
+ else
+ lua_pop(L, 2); /* pop result from 'luaL_loadbuffer' and modified line */
+ return status;
+}
+
+
+/*
+** Read multiple lines until a complete Lua statement
+*/
+static int multiline (lua_State *L) {
+ for (;;) { /* repeat until gets a complete statement */
+ size_t len;
+ const char *line = lua_tolstring(L, 1, &len); /* get what it has */
+ int status = luaL_loadbuffer(L, line, len, "=stdin"); /* try it */
+ if (!incomplete(L, status) || !pushline(L, 0)) {
+ lua_saveline(L, line); /* keep history */
+ return status; /* cannot or should not try to add continuation line */
+ }
+ lua_pushliteral(L, "\n"); /* add newline... */
+ lua_insert(L, -2); /* ...between the two lines */
+ lua_concat(L, 3); /* join them */
+ }
+}
+
+
+/*
+** Read a line and try to load (compile) it first as an expression (by
+** adding "return " in front of it) and second as a statement. Return
+** the final status of load/call with the resulting function (if any)
+** in the top of the stack.
+*/
+static int loadline (lua_State *L) {
+ int status;
+ lua_settop(L, 0);
+ if (!pushline(L, 1))
+ return -1; /* no input */
+ if ((status = addreturn(L)) != LUA_OK) /* 'return ...' did not work? */
+ status = multiline(L); /* try as command, maybe with continuation lines */
+ lua_remove(L, 1); /* remove line from the stack */
+ lua_assert(lua_gettop(L) == 1);
+ return status;
+}
+
+
+/*
+** Prints (calling the Lua 'print' function) any values on the stack
+*/
+static void l_print (lua_State *L) {
+ int n = lua_gettop(L);
+ if (n > 0) { /* any result to be printed? */
+ luaL_checkstack(L, LUA_MINSTACK, "too many results to print");
+ lua_getglobal(L, "print");
+ lua_insert(L, 1);
+ if (lua_pcall(L, n, 0, 0) != LUA_OK)
+ l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",
+ lua_tostring(L, -1)));
+ }
+}
+
+
+/*
+** Do the REPL: repeatedly read (load) a line, evaluate (call) it, and
+** print any results.
+*/
+static void doREPL (lua_State *L) {
+ int status;
+ const char *oldprogname = progname;
+ progname = NULL; /* no 'progname' on errors in interactive mode */
+ while ((status = loadline(L)) != -1) {
+ if (status == LUA_OK)
+ status = docall(L, 0, LUA_MULTRET);
+ if (status == LUA_OK) l_print(L);
+ else report(L, status);
+ }
+ lua_settop(L, 0); /* clear stack */
+ lua_writeline();
+ progname = oldprogname;
+}
+
+
+/*
+** Push on the stack the contents of table 'arg' from 1 to #arg
+*/
+static int pushargs (lua_State *L) {
+ int i, n;
+ if (lua_getglobal(L, "arg") != LUA_TTABLE)
+ luaL_error(L, "'arg' is not a table");
+ n = (int)luaL_len(L, -1);
+ luaL_checkstack(L, n + 3, "too many arguments to script");
+ for (i = 1; i <= n; i++)
+ lua_rawgeti(L, -i, i);
+ lua_remove(L, -i); /* remove table from the stack */
+ return n;
+}
+
+
+static int handle_script (lua_State *L, char **argv) {
+ int status;
+ const char *fname = argv[0];
+ if (strcmp(fname, "-") == 0 && strcmp(argv[-1], "--") != 0)
+ fname = NULL; /* stdin */
+ status = luaL_loadfile(L, fname);
+ if (status == LUA_OK) {
+ int n = pushargs(L); /* push arguments to script */
+ status = docall(L, n, LUA_MULTRET);
+ }
+ return report(L, status);
+}
+
+
+
+/* bits of various argument indicators in 'args' */
+#define has_error 1 /* bad option */
+#define has_i 2 /* -i */
+#define has_v 4 /* -v */
+#define has_e 8 /* -e */
+#define has_E 16 /* -E */
+
+/*
+** Traverses all arguments from 'argv', returning a mask with those
+** needed before running any Lua code (or an error code if it finds
+** any invalid argument). 'first' returns the first not-handled argument
+** (either the script name or a bad argument in case of error).
+*/
+static int collectargs (char **argv, int *first) {
+ int args = 0;
+ int i;
+ for (i = 1; argv[i] != NULL; i++) {
+ *first = i;
+ if (argv[i][0] != '-') /* not an option? */
+ return args; /* stop handling options */
+ switch (argv[i][1]) { /* else check option */
+ case '-': /* '--' */
+ if (argv[i][2] != '\0') /* extra characters after '--'? */
+ return has_error; /* invalid option */
+ *first = i + 1;
+ return args;
+ case '\0': /* '-' */
+ return args; /* script "name" is '-' */
+ case 'E':
+ if (argv[i][2] != '\0') /* extra characters after 1st? */
+ return has_error; /* invalid option */
+ args |= has_E;
+ break;
+ case 'i':
+ args |= has_i; /* (-i implies -v) *//* FALLTHROUGH */
+ case 'v':
+ if (argv[i][2] != '\0') /* extra characters after 1st? */
+ return has_error; /* invalid option */
+ args |= has_v;
+ break;
+ case 'e':
+ args |= has_e; /* FALLTHROUGH */
+ 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 has_error; /* no next argument or it is another option */
+ }
+ break;
+ default: /* invalid option */
+ return has_error;
+ }
+ }
+ *first = i; /* no script name */
+ return args;
+}
+
+
+/*
+** Processes options 'e' and 'l', which involve running Lua code.
+** Returns 0 if some code raises an error.
+*/
+static int runargs (lua_State *L, char **argv, int n) {
+ int i;
+ for (i = 1; i < n; i++) {
+ int option = argv[i][1];
+ lua_assert(argv[i][0] == '-'); /* already checked */
+ if (option == 'e' || option == 'l') {
+ int status;
+ const char *extra = argv[i] + 2; /* both options need an argument */
+ if (*extra == '\0') extra = argv[++i];
+ lua_assert(extra != NULL);
+ status = (option == 'e')
+ ? dostring(L, extra, "=(command line)")
+ : dolibrary(L, extra);
+ if (status != LUA_OK) return 0;
+ }
+ }
+ return 1;
+}
+
+
+
+static int handle_luainit (lua_State *L) {
+ const char *name = "=" LUA_INITVARVERSION;
+ const char *init = getenv(name + 1);
+ if (init == NULL) {
+ name = "=" LUA_INIT_VAR;
+ 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);
+}
+
+
+/*
+** Main body of stand-alone interpreter (to be called in protected mode).
+** Reads the options and handles them all.
+*/
+static int pmain (lua_State *L) {
+ int argc = (int)lua_tointeger(L, 1);
+ char **argv = (char **)lua_touserdata(L, 2);
+ int script;
+ int args = collectargs(argv, &script);
+ luaL_checkversion(L); /* check that interpreter has correct version */
+ if (argv[0] && argv[0][0]) progname = argv[0];
+ if (args == has_error) { /* bad arg? */
+ print_usage(argv[script]); /* 'script' has index of bad arg. */
+ return 0;
+ }
+ if (args & has_v) /* option '-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");
+ }
+ luaL_openlibs(L); /* open standard libraries */
+ createargtable(L, argv, argc, script); /* create table 'arg' */
+ if (!(args & has_E)) { /* no option '-E'? */
+ if (handle_luainit(L) != LUA_OK) /* run LUA_INIT */
+ return 0; /* error running LUA_INIT */
+ }
+ if (!runargs(L, argv, script)) /* execute arguments -e and -l */
+ return 0; /* something failed */
+ if (script < argc && /* execute main script (if there is one) */
+ handle_script(L, argv + script) != LUA_OK)
+ return 0;
+ if (args & has_i) /* -i option? */
+ doREPL(L); /* do read-eval-print loop */
+ else if (script == argc && !(args & (has_e | has_v))) { /* no arguments? */
+ if (lua_stdin_is_tty()) { /* running in interactive mode? */
+ print_version();
+ doREPL(L); /* do read-eval-print loop */
+ }
+ 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;
+ }
+ lua_pushcfunction(L, &pmain); /* to call 'pmain' in protected mode */
+ lua_pushinteger(L, argc); /* 1st argument */
+ lua_pushlightuserdata(L, argv); /* 2nd argument */
+ status = lua_pcall(L, 2, 1, 0); /* do the call */
+ result = lua_toboolean(L, -1); /* get result */
+ report(L, status);
+ lua_close(L);
+ return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;
+}
+