add SkLuaCanvas

third_party/lua/src/lua.c

Index: third_party/lua/src/lua.c
diff --git a/third_party/lua/src/lua.c b/third_party/lua/src/lua.c
new file mode 100644
index 0000000000000000000000000000000000000000..6a00712920263761269735d2edf40a60ec9ed2ad
--- /dev/null
+++ b/third_party/lua/src/lua.c
@@ -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;
+}
+