Lua 5.05.0

1 files changed, 433 insertions, 58 deletions

diff --git a/src/lib/lauxlib.c b/src/lib/lauxlib.c
index 4bdaeeff..ee2d1339 100644
--- a/src/lib/lauxlib.c
+++ b/src/lib/lauxlib.c
@@ -1,25 +1,101 @@
 /*
-** $Id: lauxlib.c,v 1.43 2000/10/30 13:07:48 roberto Exp $
+** $Id: lauxlib.c,v 1.100 2003/04/07 14:35:00 roberto Exp $
 ** Auxiliary functions for building Lua libraries
 ** See Copyright Notice in lua.h
 */
 
 
+#include <ctype.h>
+#include <errno.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
 
+
 /* This file uses only the official API of Lua.
 ** Any function declared here could be written as an application function.
-** With care, these functions can be used by other libraries.
 */
 
+#define lauxlib_c
+
 #include "lua.h"
 
 #include "lauxlib.h"
-#include "luadebug.h"
 
 
+/* number of prereserved references (for internal use) */
+#define RESERVED_REFS	2
+
+/* reserved references */
+#define FREELIST_REF	1	/* free list of references */
+#define ARRAYSIZE_REF	2	/* array sizes */
+
+
+/* convert a stack index to positive */
+#define abs_index(L, i)		((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
+					lua_gettop(L) + (i) + 1)
+
+
+/*
+** {======================================================
+** Error-report functions
+** =======================================================
+*/
+
+
+LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
+  lua_Debug ar;
+  lua_getstack(L, 0, &ar);
+  lua_getinfo(L, "n", &ar);
+  if (strcmp(ar.namewhat, "method") == 0) {
+    narg--;  /* do not count `self' */
+    if (narg == 0)  /* error is in the self argument itself? */
+      return luaL_error(L, "calling `%s' on bad self (%s)", ar.name, extramsg);
+  }
+  if (ar.name == NULL)
+    ar.name = "?";
+  return luaL_error(L, "bad argument #%d to `%s' (%s)",
+                        narg, ar.name, extramsg);
+}
+
+
+LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
+  const char *msg = lua_pushfstring(L, "%s expected, got %s",
+                                    tname, lua_typename(L, lua_type(L,narg)));
+  return luaL_argerror(L, narg, msg);
+}
+
+
+static void tag_error (lua_State *L, int narg, int tag) {
+  luaL_typerror(L, narg, lua_typename(L, tag)); 
+}
+
+
+LUALIB_API void luaL_where (lua_State *L, int level) {
+  lua_Debug ar;
+  if (lua_getstack(L, level, &ar)) {  /* check function at level */
+    lua_getinfo(L, "Snl", &ar);  /* get info about it */
+    if (ar.currentline > 0) {  /* is there info? */
+      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
+      return;
+    }
+  }
+  lua_pushliteral(L, "");  /* else, no information available... */
+}
+
+
+LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  luaL_where(L, 1);
+  lua_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_concat(L, 2);
+  return lua_error(L);
+}
+
+/* }====================================================== */
+
 
 LUALIB_API int luaL_findstring (const char *name, const char *const list[]) {
   int i;
@@ -29,34 +105,55 @@ LUALIB_API int luaL_findstring (const char *name, const char *const list[]) {
   return -1;  /* name not found */
 }
 
-LUALIB_API void luaL_argerror (lua_State *L, int narg, const char *extramsg) {
-  lua_Debug ar;
-  lua_getstack(L, 0, &ar);
-  lua_getinfo(L, "n", &ar);
-  if (ar.name == NULL)
-    ar.name = "?";
-  luaL_verror(L, "bad argument #%d to `%.50s' (%.100s)",
-              narg, ar.name, extramsg);
+
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+  lua_pushstring(L, tname);
+  lua_rawget(L, LUA_REGISTRYINDEX);  /* get registry.name */
+  if (!lua_isnil(L, -1))  /* name already in use? */
+    return 0;  /* leave previous value on top, but return 0 */
+  lua_pop(L, 1);
+  lua_newtable(L);  /* create metatable */
+  lua_pushstring(L, tname);
+  lua_pushvalue(L, -2);
+  lua_rawset(L, LUA_REGISTRYINDEX);  /* registry.name = metatable */
+  lua_pushvalue(L, -1);
+  lua_pushstring(L, tname);
+  lua_rawset(L, LUA_REGISTRYINDEX);  /* registry[metatable] = name */
+  return 1;
 }
 
 
-static void type_error (lua_State *L, int narg, int t) {
-  char buff[50];
-  sprintf(buff, "%.8s expected, got %.8s", lua_typename(L, t),
-                                           lua_typename(L, lua_type(L, narg)));
-  luaL_argerror(L, narg, buff);
+LUALIB_API void  luaL_getmetatable (lua_State *L, const char *tname) {
+  lua_pushstring(L, tname);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+  const char *tn;
+  if (!lua_getmetatable(L, ud)) return NULL;  /* no metatable? */
+  lua_rawget(L, LUA_REGISTRYINDEX);  /* get registry[metatable] */
+  tn = lua_tostring(L, -1);
+  if (tn && (strcmp(tn, tname) == 0)) {
+    lua_pop(L, 1);
+    return lua_touserdata(L, ud);
+  }
+  else {
+    lua_pop(L, 1);
+    return NULL;
+  }
 }
 
 
 LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
-  if (space > lua_stackspace(L))
-    luaL_verror(L, "stack overflow (%.30s)", mes);
+  if (!lua_checkstack(L, space))
+    luaL_error(L, "stack overflow (%s)", mes);
 }
 
 
-LUALIB_API void luaL_checktype(lua_State *L, int narg, int t) {
+LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
   if (lua_type(L, narg) != t)
-    type_error(L, narg, t);
+    tag_error(L, narg, t);
 }
 
 
@@ -66,55 +163,164 @@ LUALIB_API void luaL_checkany (lua_State *L, int narg) {
 }
 
 
-LUALIB_API const char *luaL_check_lstr (lua_State *L, int narg, size_t *len) {
+LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
   const char *s = lua_tostring(L, narg);
-  if (!s) type_error(L, narg, LUA_TSTRING);
+  if (!s) tag_error(L, narg, LUA_TSTRING);
   if (len) *len = lua_strlen(L, narg);
   return s;
 }
 
 
-LUALIB_API const char *luaL_opt_lstr (lua_State *L, int narg, const char *def, size_t *len) {
-  if (lua_isnull(L, narg)) {
+LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
+                                        const char *def, size_t *len) {
+  if (lua_isnoneornil(L, narg)) {
     if (len)
       *len = (def ? strlen(def) : 0);
     return def;
   }
-  else return luaL_check_lstr(L, narg, len);
+  else return luaL_checklstring(L, narg, len);
 }
 
 
-LUALIB_API double luaL_check_number (lua_State *L, int narg) {
-  double d = lua_tonumber(L, narg);
+LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
+  lua_Number d = lua_tonumber(L, narg);
   if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
-    type_error(L, narg, LUA_TNUMBER);
+    tag_error(L, narg, LUA_TNUMBER);
   return d;
 }
 
 
-LUALIB_API double luaL_opt_number (lua_State *L, int narg, double def) {
-  if (lua_isnull(L, narg)) return def;
-  else return luaL_check_number(L, narg);
+LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
+  if (lua_isnoneornil(L, narg)) return def;
+  else return luaL_checknumber(L, narg);
 }
 
 
-LUALIB_API void luaL_openlib (lua_State *L, const struct luaL_reg *l, int n) {
-  int i;
-  for (i=0; i<n; i++)
-    lua_register(L, l[i].name, l[i].func);
+LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
+  if (!lua_getmetatable(L, obj))  /* no metatable? */
+    return 0;
+  lua_pushstring(L, event);
+  lua_rawget(L, -2);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 2);  /* remove metatable and metafield */
+    return 0;
+  }
+  else {
+    lua_remove(L, -2);  /* remove only metatable */
+    return 1;
+  }
 }
 
 
-LUALIB_API void luaL_verror (lua_State *L, const char *fmt, ...) {
-  char buff[500];
-  va_list argp;
-  va_start(argp, fmt);
-  vsprintf(buff, fmt, argp);
-  va_end(argp);
-  lua_error(L, buff);
+LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
+  obj = abs_index(L, obj);
+  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
+    return 0;
+  lua_pushvalue(L, obj);
+  lua_call(L, 1, 1);
+  return 1;
 }
 
 
+LUALIB_API void luaL_openlib (lua_State *L, const char *libname,
+                              const luaL_reg *l, int nup) {
+  if (libname) {
+    lua_pushstring(L, libname);
+    lua_gettable(L, LUA_GLOBALSINDEX);  /* check whether lib already exists */
+    if (lua_isnil(L, -1)) {  /* no? */
+      lua_pop(L, 1);
+      lua_newtable(L);  /* create it */
+      lua_pushstring(L, libname);
+      lua_pushvalue(L, -2);
+      lua_settable(L, LUA_GLOBALSINDEX);  /* register it with given name */
+    }
+    lua_insert(L, -(nup+1));  /* move library table to below upvalues */
+  }
+  for (; l->name; l++) {
+    int i;
+    lua_pushstring(L, l->name);
+    for (i=0; i<nup; i++)  /* copy upvalues to the top */
+      lua_pushvalue(L, -(nup+1));
+    lua_pushcclosure(L, l->func, nup);
+    lua_settable(L, -(nup+3));
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+
+/*
+** {======================================================
+** getn-setn: size for arrays
+** =======================================================
+*/
+
+static int checkint (lua_State *L, int topop) {
+  int n = (int)lua_tonumber(L, -1);
+  if (n == 0 && !lua_isnumber(L, -1)) n = -1;
+  lua_pop(L, topop);
+  return n;
+}
+
+
+static void getsizes (lua_State *L) {
+  lua_rawgeti(L, LUA_REGISTRYINDEX, ARRAYSIZE_REF);
+  if (lua_isnil(L, -1)) {  /* no `size' table? */
+    lua_pop(L, 1);  /* remove nil */
+    lua_newtable(L);  /* create it */
+    lua_pushvalue(L, -1);  /* `size' will be its own metatable */
+    lua_setmetatable(L, -2);
+    lua_pushliteral(L, "__mode");
+    lua_pushliteral(L, "k");
+    lua_rawset(L, -3);  /* metatable(N).__mode = "k" */
+    lua_pushvalue(L, -1);
+    lua_rawseti(L, LUA_REGISTRYINDEX, ARRAYSIZE_REF);  /* store in register */
+  }
+}
+
+
+void luaL_setn (lua_State *L, int t, int n) {
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");
+  lua_rawget(L, t);
+  if (checkint(L, 1) >= 0) {  /* is there a numeric field `n'? */
+    lua_pushliteral(L, "n");  /* use it */
+    lua_pushnumber(L, (lua_Number)n);
+    lua_rawset(L, t);
+  }
+  else {  /* use `sizes' */
+    getsizes(L);
+    lua_pushvalue(L, t);
+    lua_pushnumber(L, (lua_Number)n);
+    lua_rawset(L, -3);  /* sizes[t] = n */
+    lua_pop(L, 1);  /* remove `sizes' */
+  }
+}
+
+
+int luaL_getn (lua_State *L, int t) {
+  int n;
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");  /* try t.n */
+  lua_rawget(L, t);
+  if ((n = checkint(L, 1)) >= 0) return n;
+  getsizes(L);  /* else try sizes[t] */
+  lua_pushvalue(L, t);
+  lua_rawget(L, -2);
+  if ((n = checkint(L, 2)) >= 0) return n;
+  for (n = 1; ; n++) {  /* else must count elements */
+    lua_rawgeti(L, t, n);
+    if (lua_isnil(L, -1)) break;
+    lua_pop(L, 1);
+  }
+  lua_pop(L, 1);
+  return n - 1;
+}
+
+/* }====================================================== */
+
+
+
 /*
 ** {======================================================
 ** Generic Buffer manipulation
@@ -122,7 +328,6 @@ LUALIB_API void luaL_verror (lua_State *L, const char *fmt, ...) {
 */
 
 
-#define buffempty(B)	((B)->p == (B)->buffer)
 #define bufflen(B)	((B)->p - (B)->buffer)
 #define bufffree(B)	((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
 
@@ -135,29 +340,27 @@ static int emptybuffer (luaL_Buffer *B) {
   else {
     lua_pushlstring(B->L, B->buffer, l);
     B->p = B->buffer;
-    B->level++;
+    B->lvl++;
     return 1;
   }
 }
 
 
 static void adjuststack (luaL_Buffer *B) {
-  if (B->level > 1) {
+  if (B->lvl > 1) {
     lua_State *L = B->L;
     int toget = 1;  /* number of levels to concat */
     size_t toplen = lua_strlen(L, -1);
     do {
       size_t l = lua_strlen(L, -(toget+1));
-      if (B->level - toget + 1 >= LIMIT || toplen > l) {
+      if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
         toplen += l;
         toget++;
       }
       else break;
-    } while (toget < B->level);
-    if (toget >= 2) {
-      lua_concat(L, toget);
-      B->level = B->level - toget + 1;
-    }
+    } while (toget < B->lvl);
+    lua_concat(L, toget);
+    B->lvl = B->lvl - toget + 1;
   }
 }
 
@@ -182,11 +385,8 @@ LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
 
 LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
   emptybuffer(B);
-  if (B->level == 0)
-    lua_pushlstring(B->L, NULL, 0);
-  else if (B->level > 1)
-    lua_concat(B->L, B->level);
-  B->level = 1;
+  lua_concat(B->L, B->lvl);
+  B->lvl = 1;
 }
 
 
@@ -201,7 +401,7 @@ LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
   else {
     if (emptybuffer(B))
       lua_insert(L, -2);  /* put buffer before new value */
-    B->level++;  /* add new value into B stack */
+    B->lvl++;  /* add new value into B stack */
     adjuststack(B);
   }
 }
@@ -210,7 +410,182 @@ LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
 LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
   B->L = L;
   B->p = B->buffer;
-  B->level = 0;
+  B->lvl = 0;
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_ref (lua_State *L, int t) {
+  int ref;
+  t = abs_index(L, t);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 1);  /* remove from stack */
+    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
+  }
+  lua_rawgeti(L, t, FREELIST_REF);  /* get first free element */
+  ref = (int)lua_tonumber(L, -1);  /* ref = t[FREELIST_REF] */
+  lua_pop(L, 1);  /* remove it from stack */
+  if (ref != 0) {  /* any free element? */
+    lua_rawgeti(L, t, ref);  /* remove it from list */
+    lua_rawseti(L, t, FREELIST_REF);  /* (t[FREELIST_REF] = t[ref]) */
+  }
+  else {  /* no free elements */
+    ref = luaL_getn(L, t);
+    if (ref < RESERVED_REFS)
+      ref = RESERVED_REFS;  /* skip reserved references */
+    ref++;  /* create new reference */
+    luaL_setn(L, t, ref);
+  }
+  lua_rawseti(L, t, ref);
+  return ref;
+}
+
+
+LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
+  if (ref >= 0) {
+    t = abs_index(L, t);
+    lua_rawgeti(L, t, FREELIST_REF);
+    lua_rawseti(L, t, ref);  /* t[ref] = t[FREELIST_REF] */
+    lua_pushnumber(L, (lua_Number)ref);
+    lua_rawseti(L, t, FREELIST_REF);  /* t[FREELIST_REF] = ref */
+  }
+}
+
+
+
+/*
+** {======================================================
+** Load functions
+** =======================================================
+*/
+
+typedef struct LoadF {
+  FILE *f;
+  char buff[LUAL_BUFFERSIZE];
+} LoadF;
+
+
+static const char *getF (lua_State *L, void *ud, size_t *size) {
+  LoadF *lf = (LoadF *)ud;
+  (void)L;
+  if (feof(lf->f)) return NULL;
+  *size = fread(lf->buff, 1, LUAL_BUFFERSIZE, lf->f);
+  return (*size > 0) ? lf->buff : NULL;
+}
+
+
+static int errfile (lua_State *L, int fnameindex) {
+  const char *filename = lua_tostring(L, fnameindex) + 1;
+  lua_pushfstring(L, "cannot read %s: %s", filename, strerror(errno));
+  lua_remove(L, fnameindex);
+  return LUA_ERRFILE;
+}
+
+
+LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
+  LoadF lf;
+  int status, readstatus;
+  int c;
+  int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
+  if (filename == NULL) {
+    lua_pushliteral(L, "=stdin");
+    lf.f = stdin;
+  }
+  else {
+    lua_pushfstring(L, "@%s", filename);
+    lf.f = fopen(filename, "r");
+  }
+  if (lf.f == NULL) return errfile(L, fnameindex);  /* unable to open file */
+  c = ungetc(getc(lf.f), lf.f);
+  if (!(isspace(c) || isprint(c)) && lf.f != stdin) {  /* binary file? */
+    fclose(lf.f);
+    lf.f = fopen(filename, "rb");  /* reopen in binary mode */
+    if (lf.f == NULL) return errfile(L, fnameindex); /* unable to reopen file */
+  }
+  status = lua_load(L, getF, &lf, lua_tostring(L, -1));
+  readstatus = ferror(lf.f);
+  if (lf.f != stdin) fclose(lf.f);  /* close file (even in case of errors) */
+  if (readstatus) {
+    lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
+    return errfile(L, fnameindex);
+  }
+  lua_remove(L, fnameindex);
+  return status;
+}
+
+
+typedef struct LoadS {
+  const char *s;
+  size_t size;
+} LoadS;
+
+
+static const char *getS (lua_State *L, void *ud, size_t *size) {
+  LoadS *ls = (LoadS *)ud;
+  (void)L;
+  if (ls->size == 0) return NULL;
+  *size = ls->size;
+  ls->size = 0;
+  return ls->s;
+}
+
+
+LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
+                                const char *name) {
+  LoadS ls;
+  ls.s = buff;
+  ls.size = size;
+  return lua_load(L, getS, &ls, name);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** compatibility code
+** =======================================================
+*/
+
+
+static void callalert (lua_State *L, int status) {
+  if (status != 0) {
+    lua_getglobal(L, "_ALERT");
+    if (lua_isfunction(L, -1)) {
+      lua_insert(L, -2);
+      lua_call(L, 1, 0);
+    }
+    else {  /* no _ALERT function; print it on stderr */
+      fprintf(stderr, "%s\n", lua_tostring(L, -2));
+      lua_pop(L, 2);  /* remove error message and _ALERT */
+    }
+  }
+}
+
+
+static int aux_do (lua_State *L, int status) {
+  if (status == 0) {  /* parse OK? */
+    status = lua_pcall(L, 0, LUA_MULTRET, 0);  /* call main */
+  }
+  callalert(L, status);
+  return status;
+}
+
+
+LUALIB_API int lua_dofile (lua_State *L, const char *filename) {
+  return aux_do(L, luaL_loadfile(L, filename));
+}
+
+
+LUALIB_API int lua_dobuffer (lua_State *L, const char *buff, size_t size,
+                          const char *name) {
+  return aux_do(L, luaL_loadbuffer(L, buff, size, name));
+}
+
+
+LUALIB_API int lua_dostring (lua_State *L, const char *str) {
+  return lua_dobuffer(L, str, strlen(str), str);
 }
 
 /* }====================================================== */