X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/3628146521aa93cdd499fa5058d21c7be33014bf..ea6cfe9ebd960e2cb4573c2c6f02b02931ac1f86:/src/lex.c

diff --git a/src/lex.c b/src/lex.c
index b59793bc..489fdf9c 100644
--- a/src/lex.c
+++ b/src/lex.c
@@ -1,5 +1,5 @@
 /* Token-reader for Bison's input parser,
-   Copyright (C) 1984, 1986, 1989, 1992, 2000 Free Software Foundation, Inc.
+   Copyright 1984, 1986, 1989, 1992, 2000, 2001 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -18,89 +18,50 @@
    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.  */
 
-
-/*
-   lex is the entry point.  It is called from reader.c.
-   It returns one of the token-type codes defined in lex.h.
-   When an identifier is seen, the code IDENTIFIER is returned
-   and the name is looked up in the symbol table using symtab.c;
-   symval is set to a pointer to the entry found.  */
-
-#include <stdio.h>
 #include "system.h"
+#include "getargs.h"
 #include "files.h"
-#include "getopt.h"		/* for optarg */
 #include "symtab.h"
+#include "options.h"
 #include "lex.h"
-#include "alloc.h"
 #include "complain.h"
-
-/* flags set by % directives */
-extern int definesflag;    	/* for -d */
-extern int toknumflag;   	/* for -k */
-extern int noparserflag;	/* for -n */
-extern int fixed_outfiles;  	/* for -y */
-extern int nolinesflag;    	/* for -l */
-extern int rawtoknumflag;	/* for -r */
-extern int verboseflag;	/* for -v */
-extern int debugflag;  		/* for -t */
-extern char *spec_name_prefix; 	/* for -p */
-extern char *spec_file_prefix;	/* for -b */
-/*spec_outfile is declared in files.h, for -o */
-
-extern int translations;
-
-void init_lex PARAMS((void));
-char *grow_token_buffer PARAMS((char *));
-int skip_white_space PARAMS((void));
-int safegetc PARAMS((FILE *));
-int literalchar PARAMS((char **, int *, char));
-void unlex PARAMS((int));
-int lex PARAMS((void));
-int parse_percent_token PARAMS((void));
-
-/* functions from main.c */
-extern char *printable_version PARAMS((int));
+#include "gram.h"
+#include "quote.h"
 
 /* Buffer for storing the current token.  */
-char *token_buffer;
+static struct obstack token_obstack;
+const char *token_buffer = NULL;
 
-/* Allocated size of token_buffer, not including space for terminator.  */
-int maxtoken;
-
-bucket *symval;
+bucket *symval = NULL;
 int numval;
 
-static int unlexed;		/* these two describe a token to be reread */
-static bucket *unlexed_symval;	/* by the next call to lex */
-
+/* A token to be reread, see unlex and lex. */
+static token_t unlexed = tok_undef;
+static bucket *unlexed_symval = NULL;
+static const char *unlexed_token_buffer = NULL;
 
 void
-init_lex (void)
+lex_init (void)
 {
-  maxtoken = 100;
-  token_buffer = NEW2 (maxtoken + 1, char);
-  unlexed = -1;
+  obstack_init (&token_obstack);
+  unlexed = tok_undef;
 }
 
 
-char *
-grow_token_buffer (char *p)
+void
+lex_free (void)
 {
-  int offset = p - token_buffer;
-  maxtoken *= 2;
-  token_buffer = (char *) xrealloc(token_buffer, maxtoken + 1);
-  return token_buffer + offset;
+  obstack_free (&token_obstack, NULL);
 }
 
 
 int
 skip_white_space (void)
 {
-  register int c;
-  register int inside;
+  int c;
+  int inside;
 
-  c = getc(finput);
+  c = getc (finput);
 
   for (;;)
     {
@@ -109,7 +70,8 @@ skip_white_space (void)
       switch (c)
 	{
 	case '/':
-	  c = getc(finput);
+	  /* FIXME: Should probably be merged with copy_comment.  */
+	  c = getc (finput);
 	  if (c != '*' && c != '/')
 	    {
 	      complain (_("unexpected `/' found and ignored"));
@@ -117,7 +79,7 @@ skip_white_space (void)
 	    }
 	  cplus_comment = (c == '/');
 
-	  c = getc(finput);
+	  c = getc (finput);
 
 	  inside = 1;
 	  while (inside)
@@ -125,12 +87,12 @@ skip_white_space (void)
 	      if (!cplus_comment && c == '*')
 		{
 		  while (c == '*')
-		    c = getc(finput);
+		    c = getc (finput);
 
 		  if (c == '/')
 		    {
 		      inside = 0;
-		      c = getc(finput);
+		      c = getc (finput);
 		    }
 		}
 	      else if (c == '\n')
@@ -138,12 +100,12 @@ skip_white_space (void)
 		  lineno++;
 		  if (cplus_comment)
 		    inside = 0;
-		  c = getc(finput);
+		  c = getc (finput);
 		}
 	      else if (c == EOF)
 		fatal (_("unterminated comment"));
 	      else
-		c = getc(finput);
+		c = getc (finput);
 	    }
 
 	  break;
@@ -154,7 +116,7 @@ skip_white_space (void)
 	case ' ':
 	case '\t':
 	case '\f':
-	  c = getc(finput);
+	  c = getc (finput);
 	  break;
 
 	default:
@@ -163,465 +125,484 @@ skip_white_space (void)
     }
 }
 
-/* do a getc, but give error message if EOF encountered */
+
+/*-----------------------------------------------------.
+| Do a getc, but give error message if EOF encountered |
+`-----------------------------------------------------*/
+
 int
-safegetc (FILE *f)
+xgetc (FILE *f)
 {
-  register int c = getc(f);
+  int c = getc (f);
   if (c == EOF)
     fatal (_("unexpected end of file"));
   return c;
 }
 
-/* read one literal character from finput.  process \ escapes.
-   append the normalized string version of the char to *pp.
-   assign the character code to *pcode
-   return 1 unless the character is an unescaped `term' or \n
-	report error for \n
-*/
-int
-literalchar (char **pp, int *pcode, char term)
+
+/*---------------------------------------------------------------.
+| Read one literal character from FINPUT, process \-escapes, and |
+| return the character.                                          |
+`---------------------------------------------------------------*/
+
+char
+literalchar (void)
 {
-  register int c;
-  register char *p;
-  register int code;
-  int wasquote = 0;
+  int c;
+  int res;
 
-  c = safegetc(finput);
+  c = xgetc (finput);
   if (c == '\n')
     {
       complain (_("unescaped newline in constant"));
-      ungetc(c, finput);
-      code = '?';
-      wasquote = 1;
+      ungetc (c, finput);
+      res = '?';
     }
   else if (c != '\\')
     {
-      code = c;
-      if (c == term)
-	wasquote = 1;
+      res = c;
     }
   else
     {
-      c = safegetc(finput);
-      if (c == 't')  code = '\t';
-      else if (c == 'n')  code = '\n';
-      else if (c == 'a')  code = '\007';
-      else if (c == 'r')  code = '\r';
-      else if (c == 'f')  code = '\f';
-      else if (c == 'b')  code = '\b';
-      else if (c == 'v')  code = '\013';
-      else if (c == '\\')  code = '\\';
-      else if (c == '\'')  code = '\'';
-      else if (c == '\"')  code = '\"';
+      c = xgetc (finput);
+      if (c == 't')
+	res = '\t';
+      else if (c == 'n')
+	res = '\n';
+      else if (c == 'a')
+	res = '\007';
+      else if (c == 'r')
+	res = '\r';
+      else if (c == 'f')
+	res = '\f';
+      else if (c == 'b')
+	res = '\b';
+      else if (c == 'v')
+	res = '\013';
+      else if (c == '\\')
+	res = '\\';
+      else if (c == '\'')
+	res = '\'';
+      else if (c == '\"')
+	res = '\"';
       else if (c <= '7' && c >= '0')
 	{
-	  code = 0;
+	  res = 0;
 	  while (c <= '7' && c >= '0')
 	    {
-	      code = (code * 8) + (c - '0');
-	      if (code >= 256 || code < 0)
+	      res = (res * 8) + (c - '0');
+	      if (res >= 256 || res < 0)
 		{
 		  complain (_("octal value outside range 0...255: `\\%o'"),
-			    code);
-		  code &= 0xFF;
+			    res);
+		  res &= 0xFF;
 		  break;
 		}
-	      c = safegetc(finput);
+	      c = xgetc (finput);
 	    }
-	  ungetc(c, finput);
+	  ungetc (c, finput);
 	}
       else if (c == 'x')
 	{
-	  c = safegetc(finput);
-	  code = 0;
+	  c = xgetc (finput);
+	  res = 0;
 	  while (1)
 	    {
 	      if (c >= '0' && c <= '9')
-		code *= 16,  code += c - '0';
+		res *= 16, res += c - '0';
 	      else if (c >= 'a' && c <= 'f')
-		code *= 16,  code += c - 'a' + 10;
+		res *= 16, res += c - 'a' + 10;
 	      else if (c >= 'A' && c <= 'F')
-		code *= 16,  code += c - 'A' + 10;
+		res *= 16, res += c - 'A' + 10;
 	      else
 		break;
-	      if (code >= 256 || code<0)
+	      if (res >= 256 || res < 0)
 		{
-		  complain (_("hexadecimal value above 255: `\\x%x'"),
-			    code);
-		  code &= 0xFF;
+		  complain (_("hexadecimal value above 255: `\\x%x'"), res);
+		  res &= 0xFF;
 		  break;
 		}
-	      c = safegetc(finput);
+	      c = xgetc (finput);
 	    }
-	  ungetc(c, finput);
+	  ungetc (c, finput);
 	}
       else
 	{
+	  char badchar [] = "c";
+	  badchar[0] = c;
 	  complain (_("unknown escape sequence: `\\' followed by `%s'"),
-		    printable_version(c));
-	  code = '?';
+		    quote (badchar));
+	  res = '?';
 	}
-    } /* has \ */
-
-  /* now fill token_buffer with the canonical name for this character
-     as a literal token.  Do not use what the user typed,
-     so that `\012' and `\n' can be interchangeable.  */
-
-  p = *pp;
-  if (code == term && wasquote)
-    *p++ = code;
-  else if (code == '\\')  {*p++ = '\\'; *p++ = '\\';}
-  else if (code == '\'')  {*p++ = '\\'; *p++ = '\'';}
-  else if (code == '\"')  {*p++ = '\\'; *p++ = '\"';}
-  else if (code >= 040 && code < 0177)
-    *p++ = code;
-  else if (code == '\t')  {*p++ = '\\'; *p++ = 't';}
-  else if (code == '\n')  {*p++ = '\\'; *p++ = 'n';}
-  else if (code == '\r')  {*p++ = '\\'; *p++ = 'r';}
-  else if (code == '\v')  {*p++ = '\\'; *p++ = 'v';}
-  else if (code == '\b')  {*p++ = '\\'; *p++ = 'b';}
-  else if (code == '\f')  {*p++ = '\\'; *p++ = 'f';}
-  else
-    {
-      *p++ = '\\';
-      *p++ = code / 0100 + '0';
-      *p++ = ((code / 010) & 07) + '0';
-      *p++ = (code & 07) + '0';
-    }
-  *pp = p;
-  *pcode = code;
-  return  ! wasquote;
+    }				/* has \ */
+
+  return res;
 }
 
 
 void
-unlex (int token)
+unlex (token_t token)
 {
   unlexed = token;
+  unlexed_token_buffer = token_buffer;
   unlexed_symval = symval;
 }
 
+/*-----------------------------------------------------------------.
+| We just read `<' from FIN.  Store in TOKEN_BUFFER, the type name |
+| specified between the `<...>'.                                   |
+`-----------------------------------------------------------------*/
 
-int
+void
+read_type_name (FILE *fin)
+{
+  int c = getc (fin);
+
+  while (c != '>')
+    {
+      if (c == EOF)
+	fatal (_("unterminated type name at end of file"));
+      if (c == '\n')
+	{
+	  complain (_("unterminated type name"));
+	  ungetc (c, fin);
+	  break;
+	}
+
+      obstack_1grow (&token_obstack, c);
+      c = getc (fin);
+    }
+  obstack_1grow (&token_obstack, '\0');
+  token_buffer = obstack_finish (&token_obstack);
+}
+
+
+token_t
 lex (void)
 {
-  register int c;
-  char *p;
+  int c;
+
+  /* Just to make sure. */
+  token_buffer = NULL;
 
-  if (unlexed >= 0)
+  if (unlexed != tok_undef)
     {
+      token_t res = unlexed;
       symval = unlexed_symval;
-      c = unlexed;
-      unlexed = -1;
-      return c;
+      token_buffer = unlexed_token_buffer;
+      unlexed = tok_undef;
+      return res;
     }
 
-  c = skip_white_space();
-  *token_buffer = c;	/* for error messages (token buffer always valid) */
-  token_buffer[1] = 0;
+  c = skip_white_space ();
 
   switch (c)
     {
     case EOF:
-      strcpy(token_buffer, "EOF");
-      return ENDFILE;
-
-    case 'A':  case 'B':  case 'C':  case 'D':  case 'E':
-    case 'F':  case 'G':  case 'H':  case 'I':  case 'J':
-    case 'K':  case 'L':  case 'M':  case 'N':  case 'O':
-    case 'P':  case 'Q':  case 'R':  case 'S':  case 'T':
-    case 'U':  case 'V':  case 'W':  case 'X':  case 'Y':
+      token_buffer = "EOF";
+      return tok_eof;
+
+    case 'A':    case 'B':    case 'C':    case 'D':    case 'E':
+    case 'F':    case 'G':    case 'H':    case 'I':    case 'J':
+    case 'K':    case 'L':    case 'M':    case 'N':    case 'O':
+    case 'P':    case 'Q':    case 'R':    case 'S':    case 'T':
+    case 'U':    case 'V':    case 'W':    case 'X':    case 'Y':
     case 'Z':
-    case 'a':  case 'b':  case 'c':  case 'd':  case 'e':
-    case 'f':  case 'g':  case 'h':  case 'i':  case 'j':
-    case 'k':  case 'l':  case 'm':  case 'n':  case 'o':
-    case 'p':  case 'q':  case 'r':  case 's':  case 't':
-    case 'u':  case 'v':  case 'w':  case 'x':  case 'y':
+    case 'a':    case 'b':    case 'c':    case 'd':    case 'e':
+    case 'f':    case 'g':    case 'h':    case 'i':    case 'j':
+    case 'k':    case 'l':    case 'm':    case 'n':    case 'o':
+    case 'p':    case 'q':    case 'r':    case 's':    case 't':
+    case 'u':    case 'v':    case 'w':    case 'x':    case 'y':
     case 'z':
-    case '.':  case '_':
-      p = token_buffer;
-      while (isalnum(c) || c == '_' || c == '.')
-	{
-	  if (p == token_buffer + maxtoken)
-	    p = grow_token_buffer(p);
+    case '.':    case '_':
 
-	  *p++ = c;
-	  c = getc(finput);
+      while (isalnum (c) || c == '_' || c == '.')
+	{
+	  obstack_1grow (&token_obstack, c);
+	  c = getc (finput);
 	}
-
-      *p = 0;
-      ungetc(c, finput);
-      symval = getsym(token_buffer);
-      return IDENTIFIER;
-
-    case '0':  case '1':  case '2':  case '3':  case '4':
-    case '5':  case '6':  case '7':  case '8':  case '9':
+      obstack_1grow (&token_obstack, '\0');
+      token_buffer = obstack_finish (&token_obstack);
+      ungetc (c, finput);
+      symval = getsym (token_buffer);
+      return tok_identifier;
+
+    case '0':    case '1':    case '2':    case '3':    case '4':
+    case '5':    case '6':    case '7':    case '8':    case '9':
       {
 	numval = 0;
 
-	p = token_buffer;
-	while (isdigit(c))
+	while (isdigit (c))
 	  {
-	    if (p == token_buffer + maxtoken)
-	      p = grow_token_buffer(p);
-
-	    *p++ = c;
-	    numval = numval*10 + c - '0';
-	    c = getc(finput);
+	    obstack_1grow (&token_obstack, c);
+	    numval = numval * 10 + c - '0';
+	    c = getc (finput);
 	  }
-	*p = 0;
-	ungetc(c, finput);
-	return NUMBER;
+	obstack_1grow (&token_obstack, '\0');
+	token_buffer = obstack_finish (&token_obstack);
+	ungetc (c, finput);
+	return tok_number;
       }
 
     case '\'':
-
       /* parse the literal token and compute character code in  code  */
 
-      translations = -1;
       {
-	int code, discode;
-	char discard[10], *dp;
+	int code = literalchar ();
 
-	p = token_buffer;
-	*p++ = '\'';
-	literalchar(&p, &code, '\'');
+	obstack_1grow (&token_obstack, '\'');
+	obstack_1grow (&token_obstack, code);
 
-	c = getc(finput);
+	c = getc (finput);
 	if (c != '\'')
 	  {
 	    complain (_("use \"...\" for multi-character literal tokens"));
-	    while (1)
-	      {
-		dp = discard;
-		if (! literalchar(&dp, &discode, '\''))
-		  break;
-	      }
+	    while (literalchar () != '\'')
+	      /* Skip. */;
 	  }
-	*p++ = '\'';
-	*p = 0;
-	symval = getsym(token_buffer);
-	symval->class = STOKEN;
-	if (! symval->user_token_number)
+	obstack_1grow (&token_obstack, '\'');
+	obstack_1grow (&token_obstack, '\0');
+	token_buffer = obstack_finish (&token_obstack);
+	symval = getsym (token_buffer);
+	symval->class = token_sym;
+	if (symval->user_token_number == SUNDEF)
 	  symval->user_token_number = code;
-	return IDENTIFIER;
+	return tok_identifier;
       }
 
     case '\"':
-
       /* parse the literal string token and treat as an identifier */
 
-      translations = -1;
       {
-	int code;	/* ignored here */
-	p = token_buffer;
-	*p++ = '\"';
-	while (literalchar(&p, &code, '\"'))  /* read up to and including " */
+	int code;		/* ignored here */
+
+	obstack_1grow (&token_obstack, '\"');
+	/* Read up to and including ".  */
+	do
 	  {
-	    if (p >= token_buffer + maxtoken - 4)
-	      p = grow_token_buffer(p);
+	    code = literalchar ();
+	    obstack_1grow (&token_obstack, code);
 	  }
-	*p = 0;
+	while (code != '\"');
+	obstack_1grow (&token_obstack, '\0');
+	token_buffer = obstack_finish (&token_obstack);
 
-	symval = getsym(token_buffer);
-	symval->class = STOKEN;
+	symval = getsym (token_buffer);
+	symval->class = token_sym;
 
-	return IDENTIFIER;
+	return tok_identifier;
       }
 
     case ',':
-      return COMMA;
+      token_buffer = ",";
+      return tok_comma;
 
     case ':':
-      return COLON;
+      token_buffer = ":";
+      return tok_colon;
 
     case ';':
-      return SEMICOLON;
+      token_buffer = ";";
+      return tok_semicolon;
 
     case '|':
-      return BAR;
+      token_buffer = "|";
+      return tok_bar;
 
     case '{':
-      return LEFT_CURLY;
+      token_buffer = "{";
+      return tok_left_curly;
 
     case '=':
+      obstack_1grow (&token_obstack, c);
       do
 	{
-	  c = getc(finput);
-	  if (c == '\n') lineno++;
+	  c = getc (finput);
+	  obstack_1grow (&token_obstack, c);
+	  if (c == '\n')
+	    lineno++;
 	}
-      while(c==' ' || c=='\n' || c=='\t');
+      while (c == ' ' || c == '\n' || c == '\t');
+      obstack_1grow (&token_obstack, '\0');
+      token_buffer = obstack_finish (&token_obstack);
 
       if (c == '{')
 	{
-	  strcpy(token_buffer, "={");
-	  return LEFT_CURLY;
+	  return tok_left_curly;
 	}
       else
 	{
-	  ungetc(c, finput);
-	  return ILLEGAL;
+	  ungetc (c, finput);
+	  return tok_illegal;
 	}
 
     case '<':
-      p = token_buffer;
-      c = getc(finput);
-      while (c != '>')
-	{
-	  if (c == EOF)
-	    fatal (_("unterminated type name at end of file"));
-	  if (c == '\n')
-	    {
-	      complain (_("unterminated type name"));
-	      ungetc(c, finput);
-	      break;
-	    }
-
-	  if (p == token_buffer + maxtoken)
-	    p = grow_token_buffer(p);
-
-	  *p++ = c;
-	  c = getc(finput);
-	}
-      *p = 0;
-      return TYPENAME;
-
+      read_type_name (finput);
+      return tok_typename;
 
     case '%':
-      return parse_percent_token();
+      return parse_percent_token ();
 
     default:
-      return ILLEGAL;
+      obstack_1grow (&token_obstack, c);
+      obstack_1grow (&token_obstack, '\0');
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_illegal;
     }
 }
 
-/* the following table dictates the action taken for the various
-	% directives.  A setflag value causes the named flag to be
-	set.  A retval action returns the code.
-*/
-struct percent_table_struct {
-	char *name;
-	void *setflag;
-	int retval;
-} percent_table[] =
+/* This function is a strcmp, which doesn't differentiate `-' and `_'
+   chars.  */
+
+static int
+option_strcmp (const char *left, const char *right)
 {
-  {"token", NULL, TOKEN},
-  {"term", NULL, TOKEN},
-  {"nterm", NULL, NTERM},
-  {"type", NULL, TYPE},
-  {"guard", NULL, GUARD},
-  {"union", NULL, UNION},
-  {"expect", NULL, EXPECT},
-  {"thong", NULL, THONG},
-  {"start", NULL, START},
-  {"left", NULL, LEFT},
-  {"right", NULL, RIGHT},
-  {"nonassoc", NULL, NONASSOC},
-  {"binary", NULL, NONASSOC},
-  {"semantic_parser", NULL, SEMANTIC_PARSER},
-  {"pure_parser", NULL, PURE_PARSER},
-  {"prec", NULL, PREC},
-
-  {"no_lines", &nolinesflag, NOOP}, /* -l */
-  {"raw", &rawtoknumflag, NOOP}, /* -r */
-  {"token_table", &toknumflag, NOOP}, /* -k */
-
-#if 0
-  /* These can be utilized after main is reoganized so
-     open_files() is deferred 'til after read_declarations().
-     But %{ and %union both put information into files
-     that have to be opened before read_declarations().
-     */
-  {"yacc", &fixed_outfiles, NOOP}, /* -y */
-  {"fixed_output_files", &fixed_outfiles, NOOP}, /* -y */
-  {"defines", &definesflag, NOOP}, /* -d */
-  {"no_parser", &noparserflag, NOOP}, /* -n */
-  {"output_file", &spec_outfile, SETOPT}, /* -o */
-  {"file_prefix", &spec_file_prefix, SETOPT}, /* -b */
-  {"name_prefix", &spec_name_prefix, SETOPT}, /* -p */
-
-  /* These would be acceptable, but they do not affect processing */
-  {"verbose", &verboseflag, NOOP}, /* -v */
-  {"debug", &debugflag, NOOP},	/* -t */
-  /*	{"help", <print usage stmt>, NOOP},*/	/* -h */
-  /*	{"version", <print version number> ,  NOOP},*/	/* -V */
-#endif
-
-  {NULL, NULL, ILLEGAL}
-};
+  const unsigned char *l, *r;
+  int c;
+
+  assert (left);
+  assert (right);
+  l = (const unsigned char *)left;
+  r = (const unsigned char *)right;
+  while (((c = *l - *r++) == 0 && *l != '\0')
+	 || ((*l == '-' || *l == '_') && (*r == '_' || *r == '-')))
+    l++;
+  return c;
+}
 
 /* Parse a token which starts with %.
    Assumes the % has already been read and discarded.  */
 
-int
+token_t
 parse_percent_token (void)
 {
-  register int c;
-  register char *p;
-  register struct percent_table_struct *tx;
+  const struct option_table_struct *tx = NULL;
+  const char *arg = NULL;
+  /* Where the ARG was found in token_buffer. */
+  size_t arg_offset = 0;
 
-  p = token_buffer;
-  c = getc(finput);
-  *p++ = '%';
-  *p++ = c;	/* for error msg */
-  *p = 0;
+  int c = getc (finput);
+  obstack_1grow (&token_obstack, '%');
+  obstack_1grow (&token_obstack, c);
 
   switch (c)
     {
     case '%':
-      return TWO_PERCENTS;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_two_percents;
 
     case '{':
-      return PERCENT_LEFT_CURLY;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_percent_left_curly;
 
+      /* The following guys are here for backward compatibility with
+	 very ancient Yacc versions.  The paper of Johnson mentions
+	 them (as ancient :).  */
     case '<':
-      return LEFT;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_left;
 
     case '>':
-      return RIGHT;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_right;
 
     case '2':
-      return NONASSOC;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_nonassoc;
 
     case '0':
-      return TOKEN;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_token;
 
     case '=':
-      return PREC;
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_prec;
     }
-  if (!isalpha(c))
-    return ILLEGAL;
 
-  p = token_buffer;
-  *p++ = '%';
-  while (isalpha(c) || c == '_' || c == '-')
+  if (!isalpha (c))
     {
-      if (p == token_buffer + maxtoken)
-	p = grow_token_buffer(p);
+      token_buffer = obstack_finish (&token_obstack);
+      return tok_illegal;
+    }
 
-      if (c == '-') c = '_';
-      *p++ = c;
-      c = getc(finput);
+  while (c = getc (finput), isalpha (c) || c == '_' || c == '-')
+    {
+      if (c == '_')
+	c = '-';
+      obstack_1grow (&token_obstack, c);
     }
 
-  ungetc(c, finput);
+  /* %DIRECTIVE="ARG".  Separate into
+     TOKEN_BUFFER = `%DIRECTIVE\0ARG\0'.
+     This is a bit hackish, but once we move to a Bison parser,
+     things will be cleaned up.  */
+  if (c == '=')
+    {
+      /* End of the directive.  We skip the `='. */
+      obstack_1grow (&token_obstack, '\0');
+      /* Fetch the ARG if present. */
+      c = getc (finput);
+      if (c == '"')
+	{
+	  int code;
+	  arg_offset = obstack_object_size (&token_obstack);
+	  /* Read up to and including `"'.  Do not append the closing
+	     `"' in the output: it's not part of the ARG.  */
+	  while ((code = literalchar ()) != '"')
+	    obstack_1grow (&token_obstack, code);
+	}
+      /* else: should be an error. */
+    }
+  else
+    ungetc (c, finput);
 
-  *p = 0;
+  obstack_1grow (&token_obstack, '\0');
+  token_buffer = obstack_finish (&token_obstack);
+  if (arg_offset)
+    arg = token_buffer + arg_offset;
 
   /* table lookup % directive */
-  for (tx = percent_table; tx->name; tx++)
-    if (strcmp(token_buffer+1, tx->name) == 0)
+  for (tx = option_table; tx->name; tx++)
+    if ((tx->access == opt_percent || tx->access == opt_both)
+	&& option_strcmp (token_buffer + 1, tx->name) == 0)
       break;
-  if (tx->retval == SETOPT)
-    {
-      *((char **)(tx->setflag)) = optarg;
-      return NOOP;
-    }
-  if (tx->setflag)
+
+  if (arg && tx->ret_val != tok_stropt)
+    fatal (_("`%s' supports no argument: %s"), token_buffer, quote (arg));
+
+
+  switch (tx->ret_val)
     {
-      *((int *)(tx->setflag)) = 1;
-      return NOOP;
+    case tok_stropt:
+      assert (tx->set_flag);
+      if (arg)
+	{
+	  /* Keep only the first assignment: command line options have
+	     already been processed, and we want them to have
+	     precedence.  Side effect: if this %-option is used
+	     several times, only the first is honored.  Bah.  */
+	  if (!*((char **) (tx->set_flag)))
+	    *((char **) (tx->set_flag)) = xstrdup (arg);
+	}
+      else
+	fatal (_("`%s' requires an argument"), token_buffer);
+      return tok_noop;
+      break;
+
+    case tok_intopt:
+      assert (tx->set_flag);
+      *((int *) (tx->set_flag)) = 1;
+      return tok_noop;
+      break;
+
+    case tok_obsolete:
+      fatal (_("`%s' is no longer supported"), token_buffer);
+      return tok_noop;
+      break;
+
+    default:
+      return tx->ret_val;
+      break;
     }
-  return tx->retval;
+  abort ();
 }