Lua 5.05.0

1 files changed, 201 insertions, 164 deletions

diff --git a/src/llex.c b/src/llex.c
index 4f511ab9..045e9994 100644
--- a/src/llex.c
+++ b/src/llex.c
@@ -1,24 +1,23 @@
 /*
-** $Id: llex.c,v 1.72 2000/10/20 16:39:03 roberto Exp $
+** $Id: llex.c,v 1.119 2003/03/24 12:39:34 roberto Exp $
 ** Lexical Analyzer
 ** See Copyright Notice in lua.h
 */
 
 
 #include <ctype.h>
-#include <stdio.h>
 #include <string.h>
 
+#define llex_c
+
 #include "lua.h"
 
+#include "ldo.h"
 #include "llex.h"
-#include "lmem.h"
 #include "lobject.h"
 #include "lparser.h"
 #include "lstate.h"
 #include "lstring.h"
-#include "ltable.h"
-#include "luadebug.h"
 #include "lzio.h"
 
 
@@ -29,16 +28,22 @@
 
 /* ORDER RESERVED */
 static const char *const token2string [] = {
-    "and", "break", "do", "else", "elseif", "end", "for",
-    "function", "if", "local", "nil", "not", "or", "repeat", "return", "then",
-    "until", "while", "", "..", "...", "==", ">=", "<=", "~=", "", "", "<eof>"};
+    "and", "break", "do", "else", "elseif",
+    "end", "false", "for", "function", "if",
+    "in", "local", "nil", "not", "or", "repeat",
+    "return", "then", "true", "until", "while", "*name",
+    "..", "...", "==", ">=", "<=", "~=",
+    "*number", "*string", "<eof>"
+};
 
 
 void luaX_init (lua_State *L) {
   int i;
   for (i=0; i<NUM_RESERVED; i++) {
     TString *ts = luaS_new(L, token2string[i]);
-    ts->marked = (unsigned char)(RESERVEDMARK+i);  /* reserved word */
+    luaS_fix(ts);  /* reserved words are never collected */
+    lua_assert(strlen(token2string[i])+1 <= TOKEN_LEN);
+    ts->tsv.reserved = cast(lu_byte, i+1);  /* reserved word */
   }
 }
 
@@ -48,50 +53,64 @@ void luaX_init (lua_State *L) {
 
 void luaX_checklimit (LexState *ls, int val, int limit, const char *msg) {
   if (val > limit) {
-    char buff[100];
-    sprintf(buff, "too many %.50s (limit=%d)", msg, limit);
-    luaX_error(ls, buff, ls->t.token);
+    msg = luaO_pushfstring(ls->L, "too many %s (limit=%d)", msg, limit);
+    luaX_syntaxerror(ls, msg);
   }
 }
 
 
-void luaX_syntaxerror (LexState *ls, const char *s, const char *token) {
+void luaX_errorline (LexState *ls, const char *s, const char *token, int line) {
+  lua_State *L = ls->L;
   char buff[MAXSRC];
-  luaO_chunkid(buff, ls->source->str, sizeof(buff));
-  luaO_verror(ls->L, "%.99s;\n  last token read: `%.30s' at line %d in %.80s",
-              s, token, ls->linenumber, buff);
+  luaO_chunkid(buff, getstr(ls->source), MAXSRC);
+  luaO_pushfstring(L, "%s:%d: %s near `%s'", buff, line, s, token); 
+  luaD_throw(L, LUA_ERRSYNTAX);
 }
 
 
-void luaX_error (LexState *ls, const char *s, int token) {
-  char buff[TOKEN_LEN];
-  luaX_token2str(token, buff);
-  if (buff[0] == '\0')
-    luaX_syntaxerror(ls, s, ls->L->Mbuffer);
-  else
-    luaX_syntaxerror(ls, s, buff);
+static void luaX_error (LexState *ls, const char *s, const char *token) {
+  luaX_errorline(ls, s, token, ls->linenumber);
+}
+
+
+void luaX_syntaxerror (LexState *ls, const char *msg) {
+  const char *lasttoken;
+  switch (ls->t.token) {
+    case TK_NAME:
+      lasttoken = getstr(ls->t.seminfo.ts);
+      break;
+    case TK_STRING:
+    case TK_NUMBER:
+      lasttoken = luaZ_buffer(ls->buff);
+      break;
+    default:
+      lasttoken = luaX_token2str(ls, ls->t.token);
+      break;
+  }
+  luaX_error(ls, msg, lasttoken);
 }
 
 
-void luaX_token2str (int token, char *s) {
-  if (token < 256) {
-    s[0] = (char)token;
-    s[1] = '\0';
+const char *luaX_token2str (LexState *ls, int token) {
+  if (token < FIRST_RESERVED) {
+    lua_assert(token == (unsigned char)token);
+    return luaO_pushfstring(ls->L, "%c", token);
   }
   else
-    strcpy(s, token2string[token-FIRST_RESERVED]);
+    return token2string[token-FIRST_RESERVED];
 }
 
 
-static void luaX_invalidchar (LexState *ls, int c) {
-  char buff[8];
-  sprintf(buff, "0x%02X", c);
-  luaX_syntaxerror(ls, "invalid control char", buff);
+static void luaX_lexerror (LexState *ls, const char *s, int token) {
+  if (token == TK_EOS)
+    luaX_error(ls, s, luaX_token2str(ls, token));
+  else
+    luaX_error(ls, s, luaZ_buffer(ls->buff));
 }
 
 
 static void inclinenumber (LexState *LS) {
-  next(LS);  /* skip '\n' */
+  next(LS);  /* skip `\n' */
   ++LS->linenumber;
   luaX_checklimit(LS, LS->linenumber, MAX_INT, "lines in a chunk");
 }
@@ -122,159 +141,173 @@ void luaX_setinput (lua_State *L, LexState *LS, ZIO *z, TString *source) {
 */
 
 
-/* use Mbuffer to store names, literal strings and numbers */
+/* use buffer to store names, literal strings and numbers */
+
+/* extra space to allocate when growing buffer */
+#define EXTRABUFF	32
+
+/* maximum number of chars that can be read without checking buffer size */
+#define MAXNOCHECK	5
 
-#define EXTRABUFF	128
-#define checkbuffer(L, n, len)	if ((len)+(n) > L->Mbuffsize) \
-                                  luaO_openspace(L, (len)+(n)+EXTRABUFF)
+#define checkbuffer(LS, len)	\
+    if (((len)+MAXNOCHECK)*sizeof(char) > luaZ_sizebuffer((LS)->buff)) \
+      luaZ_openspace((LS)->L, (LS)->buff, (len)+EXTRABUFF)
 
-#define save(L, c, l)	(L->Mbuffer[l++] = (char)c)
-#define save_and_next(L, LS, l)  (save(L, LS->current, l), next(LS))
+#define save(LS, c, l) \
+	(luaZ_buffer((LS)->buff)[l++] = cast(char, c))
+#define save_and_next(LS, l)  (save(LS, LS->current, l), next(LS))
 
 
-static const char *readname (LexState *LS) {
-  lua_State *L = LS->L;
+static size_t readname (LexState *LS) {
   size_t l = 0;
-  checkbuffer(L, 10, l);
+  checkbuffer(LS, l);
   do {
-    checkbuffer(L, 10, l);
-    save_and_next(L, LS, l);
+    checkbuffer(LS, l);
+    save_and_next(LS, l);
   } while (isalnum(LS->current) || LS->current == '_');
-  save(L, '\0', l);
-  return L->Mbuffer;
+  save(LS, '\0', l);
+  return l-1;
 }
 
 
 /* LUA_NUMBER */
-static void read_number (LexState *LS, int comma, SemInfo *seminfo) {
-  lua_State *L = LS->L;
+static void read_numeral (LexState *LS, int comma, SemInfo *seminfo) {
   size_t l = 0;
-  checkbuffer(L, 10, l);
-  if (comma) save(L, '.', l);
+  checkbuffer(LS, l);
+  if (comma) save(LS, '.', l);
   while (isdigit(LS->current)) {
-    checkbuffer(L, 10, l);
-    save_and_next(L, LS, l);
+    checkbuffer(LS, l);
+    save_and_next(LS, l);
   }
   if (LS->current == '.') {
-    save_and_next(L, LS, l);
+    save_and_next(LS, l);
     if (LS->current == '.') {
-      save_and_next(L, LS, l);
-      save(L, '\0', l);
-      luaX_error(LS, "ambiguous syntax"
-           " (decimal point x string concatenation)", TK_NUMBER);
+      save_and_next(LS, l);
+      save(LS, '\0', l);
+      luaX_lexerror(LS,
+                 "ambiguous syntax (decimal point x string concatenation)",
+                 TK_NUMBER);
     }
   }
   while (isdigit(LS->current)) {
-    checkbuffer(L, 10, l);
-    save_and_next(L, LS, l);
+    checkbuffer(LS, l);
+    save_and_next(LS, l);
   }
   if (LS->current == 'e' || LS->current == 'E') {
-    save_and_next(L, LS, l);  /* read 'E' */
+    save_and_next(LS, l);  /* read `E' */
     if (LS->current == '+' || LS->current == '-')
-      save_and_next(L, LS, l);  /* optional exponent sign */
+      save_and_next(LS, l);  /* optional exponent sign */
     while (isdigit(LS->current)) {
-      checkbuffer(L, 10, l);
-      save_and_next(L, LS, l);
+      checkbuffer(LS, l);
+      save_and_next(LS, l);
     }
   }
-  save(L, '\0', l);
-  if (!luaO_str2d(L->Mbuffer, &seminfo->r))
-    luaX_error(LS, "malformed number", TK_NUMBER);
+  save(LS, '\0', l);
+  if (!luaO_str2d(luaZ_buffer(LS->buff), &seminfo->r))
+    luaX_lexerror(LS, "malformed number", TK_NUMBER);
 }
 
 
 static void read_long_string (LexState *LS, SemInfo *seminfo) {
-  lua_State *L = LS->L;
   int cont = 0;
   size_t l = 0;
-  checkbuffer(L, 10, l);
-  save(L, '[', l);  /* save first '[' */
-  save_and_next(L, LS, l);  /* pass the second '[' */
+  checkbuffer(LS, l);
+  save(LS, '[', l);  /* save first `[' */
+  save_and_next(LS, l);  /* pass the second `[' */
+  if (LS->current == '\n')  /* string starts with a newline? */
+    inclinenumber(LS);  /* skip it */
   for (;;) {
-    checkbuffer(L, 10, l);
+    checkbuffer(LS, l);
     switch (LS->current) {
       case EOZ:
-        save(L, '\0', l);
-        luaX_error(LS, "unfinished long string", TK_STRING);
+        save(LS, '\0', l);
+        luaX_lexerror(LS, (seminfo) ? "unfinished long string" :
+                                   "unfinished long comment", TK_EOS);
         break;  /* to avoid warnings */
       case '[':
-        save_and_next(L, LS, l);
+        save_and_next(LS, l);
         if (LS->current == '[') {
           cont++;
-          save_and_next(L, LS, l);
+          save_and_next(LS, l);
         }
         continue;
       case ']':
-        save_and_next(L, LS, l);
+        save_and_next(LS, l);
         if (LS->current == ']') {
           if (cont == 0) goto endloop;
           cont--;
-          save_and_next(L, LS, l);
+          save_and_next(LS, l);
         }
         continue;
       case '\n':
-        save(L, '\n', l);
+        save(LS, '\n', l);
         inclinenumber(LS);
+        if (!seminfo) l = 0;  /* reset buffer to avoid wasting space */
         continue;
       default:
-        save_and_next(L, LS, l);
+        save_and_next(LS, l);
     }
   } endloop:
-  save_and_next(L, LS, l);  /* skip the second ']' */
-  save(L, '\0', l);
-  seminfo->ts = luaS_newlstr(L, L->Mbuffer+2, l-5);
+  save_and_next(LS, l);  /* skip the second `]' */
+  save(LS, '\0', l);
+  if (seminfo)
+    seminfo->ts = luaS_newlstr(LS->L, luaZ_buffer(LS->buff) + 2, l - 5);
 }
 
 
 static void read_string (LexState *LS, int del, SemInfo *seminfo) {
-  lua_State *L = LS->L;
   size_t l = 0;
-  checkbuffer(L, 10, l);
-  save_and_next(L, LS, l);
+  checkbuffer(LS, l);
+  save_and_next(LS, l);
   while (LS->current != del) {
-    checkbuffer(L, 10, l);
+    checkbuffer(LS, l);
     switch (LS->current) {
-      case EOZ:  case '\n':
-        save(L, '\0', l);
-        luaX_error(LS, "unfinished string", TK_STRING);
+      case EOZ:
+        save(LS, '\0', l);
+        luaX_lexerror(LS, "unfinished string", TK_EOS);
+        break;  /* to avoid warnings */
+      case '\n':
+        save(LS, '\0', l);
+        luaX_lexerror(LS, "unfinished string", TK_STRING);
         break;  /* to avoid warnings */
       case '\\':
-        next(LS);  /* do not save the '\' */
+        next(LS);  /* do not save the `\' */
         switch (LS->current) {
-          case 'a': save(L, '\a', l); next(LS); break;
-          case 'b': save(L, '\b', l); next(LS); break;
-          case 'f': save(L, '\f', l); next(LS); break;
-          case 'n': save(L, '\n', l); next(LS); break;
-          case 'r': save(L, '\r', l); next(LS); break;
-          case 't': save(L, '\t', l); next(LS); break;
-          case 'v': save(L, '\v', l); next(LS); break;
-          case '\n': save(L, '\n', l); inclinenumber(LS); break;
-          case '0': case '1': case '2': case '3': case '4':
-          case '5': case '6': case '7': case '8': case '9': {
-            int c = 0;
-            int i = 0;
-            do {
-              c = 10*c + (LS->current-'0');
-              next(LS);
-            } while (++i<3 && isdigit(LS->current));
-            if (c != (unsigned char)c) {
-              save(L, '\0', l);
-              luaX_error(LS, "escape sequence too large", TK_STRING);
+          case 'a': save(LS, '\a', l); next(LS); break;
+          case 'b': save(LS, '\b', l); next(LS); break;
+          case 'f': save(LS, '\f', l); next(LS); break;
+          case 'n': save(LS, '\n', l); next(LS); break;
+          case 'r': save(LS, '\r', l); next(LS); break;
+          case 't': save(LS, '\t', l); next(LS); break;
+          case 'v': save(LS, '\v', l); next(LS); break;
+          case '\n': save(LS, '\n', l); inclinenumber(LS); break;
+          case EOZ: break;  /* will raise an error next loop */
+          default: {
+            if (!isdigit(LS->current))
+              save_and_next(LS, l);  /* handles \\, \", \', and \? */
+            else {  /* \xxx */
+              int c = 0;
+              int i = 0;
+              do {
+                c = 10*c + (LS->current-'0');
+                next(LS);
+              } while (++i<3 && isdigit(LS->current));
+              if (c > UCHAR_MAX) {
+                save(LS, '\0', l);
+                luaX_lexerror(LS, "escape sequence too large", TK_STRING);
+              }
+              save(LS, c, l);
             }
-            save(L, c, l);
-            break;
           }
-          default:  /* handles \\, \", \', and \? */
-            save_and_next(L, LS, l);
         }
         break;
       default:
-        save_and_next(L, LS, l);
+        save_and_next(LS, l);
     }
   }
-  save_and_next(L, LS, l);  /* skip delimiter */
-  save(L, '\0', l);
-  seminfo->ts = luaS_newlstr(L, L->Mbuffer+1, l-3);
+  save_and_next(LS, l);  /* skip delimiter */
+  save(LS, '\0', l);
+  seminfo->ts = luaS_newlstr(LS->L, luaZ_buffer(LS->buff) + 1, l - 3);
 }
 
 
@@ -282,58 +315,56 @@ int luaX_lex (LexState *LS, SemInfo *seminfo) {
   for (;;) {
     switch (LS->current) {
 
-      case ' ': case '\t': case '\r':  /* `\r' to avoid problems with DOS */
-        next(LS);
-        continue;
-
-      case '\n':
+      case '\n': {
         inclinenumber(LS);
         continue;
-
-      case '$':
-        luaX_error(LS, "unexpected `$' (pragmas are no longer supported)", '$');
-        break;
-
-      case '-':
+      }
+      case '-': {
         next(LS);
         if (LS->current != '-') return '-';
-        do { next(LS); } while (LS->current != '\n' && LS->current != EOZ);
+        /* else is a comment */
+        next(LS);
+        if (LS->current == '[' && (next(LS), LS->current == '['))
+          read_long_string(LS, NULL);  /* long comment */
+        else  /* short comment */
+          while (LS->current != '\n' && LS->current != EOZ)
+            next(LS);
         continue;
-
-      case '[':
+      }
+      case '[': {
         next(LS);
         if (LS->current != '[') return '[';
         else {
           read_long_string(LS, seminfo);
           return TK_STRING;
         }
-
-      case '=':
+      }
+      case '=': {
         next(LS);
         if (LS->current != '=') return '=';
         else { next(LS); return TK_EQ; }
-
-      case '<':
+      }
+      case '<': {
         next(LS);
         if (LS->current != '=') return '<';
         else { next(LS); return TK_LE; }
-
-      case '>':
+      }
+      case '>': {
         next(LS);
         if (LS->current != '=') return '>';
         else { next(LS); return TK_GE; }
-
-      case '~':
+      }
+      case '~': {
         next(LS);
         if (LS->current != '=') return '~';
         else { next(LS); return TK_NE; }
-
+      }
       case '"':
-      case '\'':
+      case '\'': {
         read_string(LS, LS->current, seminfo);
         return TK_STRING;
-
-      case '.':
+      }
+      case '.': {
         next(LS);
         if (LS->current == '.') {
           next(LS);
@@ -345,36 +376,42 @@ int luaX_lex (LexState *LS, SemInfo *seminfo) {
         }
         else if (!isdigit(LS->current)) return '.';
         else {
-          read_number(LS, 1, seminfo);
+          read_numeral(LS, 1, seminfo);
           return TK_NUMBER;
         }
-
-      case '0': case '1': case '2': case '3': case '4':
-      case '5': case '6': case '7': case '8': case '9':
-        read_number(LS, 0, seminfo);
-        return TK_NUMBER;
-
-      case EOZ:
+      }
+      case EOZ: {
         return TK_EOS;
-
-      case '_': goto tname;
-
-      default:
-        if (!isalpha(LS->current)) {
-          int c = LS->current;
-          if (iscntrl(c))
-            luaX_invalidchar(LS, c);
+      }
+      default: {
+        if (isspace(LS->current)) {
           next(LS);
-          return c;
+          continue;
+        }
+        else if (isdigit(LS->current)) {
+          read_numeral(LS, 0, seminfo);
+          return TK_NUMBER;
         }
-        tname: {  /* identifier or reserved word */
-          TString *ts = luaS_new(LS->L, readname(LS));
-          if (ts->marked >= RESERVEDMARK)  /* reserved word? */
-            return ts->marked-RESERVEDMARK+FIRST_RESERVED;
+        else if (isalpha(LS->current) || LS->current == '_') {
+          /* identifier or reserved word */
+          size_t l = readname(LS);
+          TString *ts = luaS_newlstr(LS->L, luaZ_buffer(LS->buff), l);
+          if (ts->tsv.reserved > 0)  /* reserved word? */
+            return ts->tsv.reserved - 1 + FIRST_RESERVED;
           seminfo->ts = ts;
           return TK_NAME;
         }
+        else {
+          int c = LS->current;
+          if (iscntrl(c))
+            luaX_error(LS, "invalid control char",
+                           luaO_pushfstring(LS->L, "char(%d)", c));
+          next(LS);
+          return c;  /* single-char tokens (+ - / ...) */
+        }
+      }
     }
   }
 }
 
+#undef next