* data/Makefile.am (dist_pkgdata_DATA): Remove push.c.

[bison.git] / src / scan-gram.l

diff --git a/src/scan-gram.l b/src/scan-gram.l
index fd384061e28bf220b66dfe839d5bad74f10502df..697f52f054a73058ae287624c6fdf6ff9f757d46 100644 (file)
--- a/src/scan-gram.l
+++ b/src/scan-gram.l
@@ -1,12 +1,13 @@
 /* Bison Grammar Scanner                             -*- C -*-
 
 /* Bison Grammar Scanner                             -*- C -*-
 

-   Copyright (C) 2002 Free Software Foundation, Inc.
+   Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation,
+   Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 

-   This program is free software; you can redistribute it and/or modify
+   This program is free software: you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by
    it under the terms of the GNU General Public License as published by

-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation, either version 3 of the License, or

    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,


@@ -15,105 +16,83 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License

-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-   02111-1307  USA
-*/
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

 
 

-%option debug nodefault noyywrap never-interactive
+%option debug nodefault nounput noyywrap never-interactive

 %option prefix="gram_" outfile="lex.yy.c"
 
 %{
 %option prefix="gram_" outfile="lex.yy.c"
 
 %{

-#include "system.h"
+/* Work around a bug in flex 2.5.31.  See Debian bug 333231
+   <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
+#undef gram_wrap
+#define gram_wrap() 1

 
 

-#include <mbswidth.h>
-#include <get-errno.h>
-#include <quote.h>
+#define FLEX_PREFIX(Id) gram_ ## Id
+#include "flex-scanner.h"

 
 #include "complain.h"
 #include "files.h"
 
 #include "complain.h"
 #include "files.h"

-#include "getargs.h"

 #include "gram.h"
 #include "gram.h"

+#include "quotearg.h"

 #include "reader.h"
 #include "uniqstr.h"
 
 #include "reader.h"
 #include "uniqstr.h"
 

+#include <mbswidth.h>
+#include <quote.h>
+
+#include "scan-gram.h"
+
+#define YY_DECL GRAM_LEX_DECL
+

 #define YY_USER_INIT                                   \
 #define YY_USER_INIT                                   \

-  do                                                   \
-    {                                                  \
-      scanner_cursor.file = current_file;              \
-      scanner_cursor.line = 1;                         \
-      scanner_cursor.column = 1;                       \
-    }                                                  \
-  while (0)
+   code_start = scanner_cursor = loc->start;           \

 
 /* Location of scanner cursor.  */
 
 /* Location of scanner cursor.  */

-boundary scanner_cursor;
+static boundary scanner_cursor;

 
 

-static void adjust_location (location *, char const *, size_t);
-#define YY_USER_ACTION  adjust_location (loc, yytext, yyleng);
+#define YY_USER_ACTION  location_compute (loc, &scanner_cursor, yytext, yyleng);

 
 static size_t no_cr_read (FILE *, char *, size_t);
 #define YY_INPUT(buf, result, size) ((result) = no_cr_read (yyin, buf, size))
 
 
 static size_t no_cr_read (FILE *, char *, size_t);
 #define YY_INPUT(buf, result, size) ((result) = no_cr_read (yyin, buf, size))
 

-
-/* OBSTACK_FOR_STRING -- Used to store all the characters that we need to
-   keep (to construct ID, STRINGS etc.).  Use the following macros to
-   use it.
-
-   Use STRING_GROW to append what has just been matched, and
-   STRING_FINISH to end the string (it puts the ending 0).
-   STRING_FINISH also stores this string in LAST_STRING, which can be
-   used, and which is used by STRING_FREE to free the last string.  */
-
-static struct obstack obstack_for_string;
-

 /* A string representing the most recently saved token.  */
 static char *last_string;
 
 /* A string representing the most recently saved token.  */
 static char *last_string;
 

-
-#define STRING_GROW   \
-  obstack_grow (&obstack_for_string, yytext, yyleng)
-
-#define STRING_FINISH                                  \
-  do {                                                 \
-    obstack_1grow (&obstack_for_string, '\0');         \
-    last_string = obstack_finish (&obstack_for_string);        \
-  } while (0)
-
-#define STRING_FREE \
-  obstack_free (&obstack_for_string, last_string)
-

 void
 void

-scanner_last_string_free (void)
+gram_scanner_last_string_free (void)

 {
   STRING_FREE;
 }
 
 {
   STRING_FREE;
 }
 

-/* Within well-formed rules, RULE_LENGTH is the number of values in
-   the current rule so far, which says where to find `$0' with respect
-   to the top of the stack.  It is not the same as the rule->length in
-   the case of mid rule actions.
-
-   Outside of well-formed rules, RULE_LENGTH has an undefined value.  */
-static int rule_length;
-
-static void handle_dollar (braced_code code_kind, char *cp, location loc);
-static void handle_at (braced_code code_kind, char *cp, location loc);
-static void handle_syncline (char *args);
+static void handle_syncline (char *, location);
+static unsigned long int scan_integer (char const *p, int base, location loc);

 static int convert_ucn_to_byte (char const *hex_text);
 static int convert_ucn_to_byte (char const *hex_text);

-static void unexpected_end_of_file (boundary, char const *);
+static void unexpected_eof (boundary, char const *);
+static void unexpected_newline (boundary, char const *);

 
 %}
 
 %}

-%x SC_COMMENT SC_LINE_COMMENT SC_YACC_COMMENT
-%x SC_STRING SC_CHARACTER
-%x SC_AFTER_IDENTIFIER
+ /* A C-like comment in directives/rules. */
+%x SC_YACC_COMMENT
+ /* Strings and characters in directives/rules. */

 %x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER
 %x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER

-%x SC_BRACED_CODE SC_PROLOGUE SC_EPILOGUE
+ /* A identifier was just read in directives/rules.  Special state
+    to capture the sequence `identifier :'. */
+%x SC_AFTER_IDENTIFIER
+
+ /* Three types of user code:
+    - prologue (code between `%{' `%}' in the first section, before %%);
+    - actions, printers, union, etc, (between braced in the middle section);
+    - epilogue (everything after the second %%). */
+%x SC_PROLOGUE SC_BRACED_CODE SC_EPILOGUE
+ /* C and C++ comments in code. */
+%x SC_COMMENT SC_LINE_COMMENT
+ /* Strings and characters in code. */
+%x SC_STRING SC_CHARACTER

 
 letter   [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]
 id       {letter}({letter}|[0-9])*
 directive %{letter}({letter}|[0-9]|-)*
 
 letter   [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]
 id       {letter}({letter}|[0-9])*
 directive %{letter}({letter}|[0-9]|-)*

-int      [0-9]+
+int      [0-9]+

 
 /* POSIX says that a tag must be both an id and a C union member, but
    historically almost any character is allowed in a tag.  We disallow
 
 /* POSIX says that a tag must be both an id and a C union member, but
    historically almost any character is allowed in a tag.  We disallow


@@ -133,14 +112,16 @@ splice     (\\[ \f\t\v]*\n)*
   int context_state IF_LINT (= 0);
 
   /* Location of most recent identifier, when applicable.  */
   int context_state IF_LINT (= 0);
 
   /* Location of most recent identifier, when applicable.  */

-  location id_loc IF_LINT (= *loc);
+  location id_loc IF_LINT (= empty_location);

 
 

-  /* Where containing code started, when applicable.  */
-  boundary code_start IF_LINT (= loc->start);
+  /* Where containing code started, when applicable.  Its initial
+     value is relevant only when yylex is invoked in the SC_EPILOGUE
+     start condition.  */
+  boundary code_start = scanner_cursor;

 
   /* Where containing comment or string or character literal started,
      when applicable.  */
 
   /* Where containing comment or string or character literal started,
      when applicable.  */

-  boundary token_start IF_LINT (= loc->start);
+  boundary token_start IF_LINT (= scanner_cursor);

 %}
 
 
 %}
 
 


@@ -150,16 +131,20 @@ splice     (\\[ \f\t\v]*\n)*
 
 <INITIAL,SC_AFTER_IDENTIFIER>
 {
 
 <INITIAL,SC_AFTER_IDENTIFIER>
 {

-  [ \f\n\t\v]  ;
-
-  /* Comments. */
-  "/*"         token_start = loc->start; context_state = YY_START; BEGIN SC_YACC_COMMENT;
+  /* Comments and white space.  */
+  ","         warn_at (*loc, _("stray `,' treated as white space"));
+  [ \f\n\t\v]  |

   "//".*       ;
   "//".*       ;

+  "/*" {
+    token_start = loc->start;
+    context_state = YY_START;
+    BEGIN SC_YACC_COMMENT;
+  }

 
   /* #line directives are not documented, and may be withdrawn or
      modified in future versions of Bison.  */
   ^"#line "{int}" \"".*"\"\n" {
 
   /* #line directives are not documented, and may be withdrawn or
      modified in future versions of Bison.  */
   ^"#line "{int}" \"".*"\"\n" {

-    handle_syncline (yytext + sizeof "#line " - 1);
+    handle_syncline (yytext + sizeof "#line " - 1, *loc);

   }
 }
 
   }
 }
 


@@ -169,70 +154,71 @@ splice     (\\[ \f\t\v]*\n)*
   `----------------------------*/
 <INITIAL>
 {
   `----------------------------*/
 <INITIAL>
 {

-  "%binary"               return PERCENT_NONASSOC;
-  "%debug"                return PERCENT_DEBUG;
-  "%define"               return PERCENT_DEFINE;
-  "%defines"              return PERCENT_DEFINES;
-  "%destructor"           return PERCENT_DESTRUCTOR;
-  "%dprec"               return PERCENT_DPREC;
-  "%error"[-_]"verbose"   return PERCENT_ERROR_VERBOSE;
-  "%expect"               return PERCENT_EXPECT;
-  "%file-prefix"          return PERCENT_FILE_PREFIX;
+  "%binary"                        return PERCENT_NONASSOC;
+  "%code"                           return PERCENT_CODE;
+  "%debug"                         return PERCENT_DEBUG;
+  "%default"[-_]"prec"             return PERCENT_DEFAULT_PREC;
+  "%define"                        return PERCENT_DEFINE;
+  "%defines"                       return PERCENT_DEFINES;
+  "%destructor"                            return PERCENT_DESTRUCTOR;
+  "%dprec"                         return PERCENT_DPREC;
+  "%error"[-_]"verbose"            return PERCENT_ERROR_VERBOSE;
+  "%expect"                        return PERCENT_EXPECT;
+  "%expect"[-_]"rr"                return PERCENT_EXPECT_RR;
+  "%file-prefix"                   return PERCENT_FILE_PREFIX;

   "%fixed"[-_]"output"[-_]"files"   return PERCENT_YACC;
   "%fixed"[-_]"output"[-_]"files"   return PERCENT_YACC;

-  "%glr-parser"           return PERCENT_GLR_PARSER;
-  "%left"                 return PERCENT_LEFT;
-  "%locations"            return PERCENT_LOCATIONS;
-  "%merge"               return PERCENT_MERGE;
-  "%name"[-_]"prefix"     return PERCENT_NAME_PREFIX;
-  "%no"[-_]"lines"        return PERCENT_NO_LINES;
-  "%nonassoc"             return PERCENT_NONASSOC;
-  "%nterm"                return PERCENT_NTERM;
-  "%output"               return PERCENT_OUTPUT;
-  "%parse-param"          return PERCENT_PARSE_PARAM;
-  "%prec"                 rule_length--; return PERCENT_PREC;
-  "%printer"              return PERCENT_PRINTER;
-  "%pure"[-_]"parser"     return PERCENT_PURE_PARSER;
-  "%right"                return PERCENT_RIGHT;
-  "%lex-param"            return PERCENT_LEX_PARAM;
-  "%skeleton"             return PERCENT_SKELETON;
-  "%start"                return PERCENT_START;
-  "%term"                 return PERCENT_TOKEN;
-  "%token"                return PERCENT_TOKEN;
-  "%token"[-_]"table"     return PERCENT_TOKEN_TABLE;
-  "%type"                 return PERCENT_TYPE;
-  "%union"                return PERCENT_UNION;
-  "%verbose"              return PERCENT_VERBOSE;
-  "%yacc"                 return PERCENT_YACC;
+  "%initial-action"                return PERCENT_INITIAL_ACTION;
+  "%glr-parser"                    return PERCENT_GLR_PARSER;
+  "%language"                      return PERCENT_LANGUAGE;
+  "%left"                          return PERCENT_LEFT;
+  "%lex-param"                     return PERCENT_LEX_PARAM;
+  "%locations"                     return PERCENT_LOCATIONS;
+  "%merge"                         return PERCENT_MERGE;
+  "%name"[-_]"prefix"              return PERCENT_NAME_PREFIX;
+  "%no"[-_]"default"[-_]"prec"     return PERCENT_NO_DEFAULT_PREC;
+  "%no"[-_]"lines"                 return PERCENT_NO_LINES;
+  "%nonassoc"                      return PERCENT_NONASSOC;
+  "%nondeterministic-parser"               return PERCENT_NONDETERMINISTIC_PARSER;
+  "%nterm"                         return PERCENT_NTERM;
+  "%output"                        return PERCENT_OUTPUT;
+  "%parse-param"                   return PERCENT_PARSE_PARAM;
+  "%prec"                          return PERCENT_PREC;
+  "%printer"                       return PERCENT_PRINTER;
+  "%pure"[-_]"parser"              return PERCENT_PURE_PARSER;
+  "%require"                       return PERCENT_REQUIRE;
+  "%right"                         return PERCENT_RIGHT;
+  "%skeleton"                      return PERCENT_SKELETON;
+  "%start"                         return PERCENT_START;
+  "%term"                          return PERCENT_TOKEN;
+  "%token"                         return PERCENT_TOKEN;
+  "%token"[-_]"table"              return PERCENT_TOKEN_TABLE;
+  "%type"                          return PERCENT_TYPE;
+  "%union"                         return PERCENT_UNION;
+  "%verbose"                       return PERCENT_VERBOSE;
+  "%yacc"                          return PERCENT_YACC;

 
   {directive} {
     complain_at (*loc, _("invalid directive: %s"), quote (yytext));
   }
 
   "="                     return EQUAL;
 
   {directive} {
     complain_at (*loc, _("invalid directive: %s"), quote (yytext));
   }
 
   "="                     return EQUAL;

-  "|"                     rule_length = 0; return PIPE;
+  "|"                     return PIPE;

   ";"                     return SEMICOLON;
   ";"                     return SEMICOLON;

-
-  "," {
-    warn_at (*loc, _("stray `,' treated as white space"));
-  }
+  "<*>"                   return TYPE_TAG_ANY;
+  "<>"                    return TYPE_TAG_NONE;

 
   {id} {
 
   {id} {

-    val->symbol = symbol_get (yytext, *loc);
+    val->uniqstr = uniqstr_new (yytext);

     id_loc = *loc;
     id_loc = *loc;

-    rule_length++;

     BEGIN SC_AFTER_IDENTIFIER;
   }
 
   {int} {
     BEGIN SC_AFTER_IDENTIFIER;
   }
 
   {int} {

-    unsigned long num;
-    set_errno (0);
-    num = strtoul (yytext, 0, 10);
-    if (INT_MAX < num || get_errno ())
-      {
-       complain_at (*loc, _("integer out of range: %s"), quote (yytext));
-       num = INT_MAX;
-      }
-    val->integer = num;
+    val->integer = scan_integer (yytext, 10, *loc);
+    return INT;
+  }
+  0[xX][0-9abcdefABCDEF]+ {
+    val->integer = scan_integer (yytext, 16, *loc);

     return INT;
   }
 
     return INT;
   }
 


@@ -240,7 +226,7 @@ splice       (\\[ \f\t\v]*\n)*
   "'"        STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER;
 
   /* Strings. */
   "'"        STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER;
 
   /* Strings. */

-  "\""       STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_STRING;
+  "\""       token_start = loc->start; BEGIN SC_ESCAPED_STRING;

 
   /* Prologue. */
   "%{"        code_start = loc->start; BEGIN SC_PROLOGUE;
 
   /* Prologue. */
   "%{"        code_start = loc->start; BEGIN SC_PROLOGUE;


@@ -265,16 +251,18 @@ splice     (\\[ \f\t\v]*\n)*
   "%%" {
     static int percent_percent_count;
     if (++percent_percent_count == 2)
   "%%" {
     static int percent_percent_count;
     if (++percent_percent_count == 2)

-      {
-       code_start = loc->start;
-       BEGIN SC_EPILOGUE;
-      }
+      BEGIN SC_EPILOGUE;

     return PERCENT_PERCENT;
   }
 
   . {
     complain_at (*loc, _("invalid character: %s"), quote (yytext));
   }
     return PERCENT_PERCENT;
   }
 
   . {
     complain_at (*loc, _("invalid character: %s"), quote (yytext));
   }

+
+  <<EOF>> {
+    loc->start = loc->end = scanner_cursor;
+    yyterminate ();
+  }

 }
 
 
 }
 
 


@@ -285,7 +273,6 @@ splice       (\\[ \f\t\v]*\n)*
 <SC_AFTER_IDENTIFIER>
 {
   ":" {
 <SC_AFTER_IDENTIFIER>
 {
   ":" {

-    rule_length = 0;

     *loc = id_loc;
     BEGIN INITIAL;
     return ID_COLON;
     *loc = id_loc;
     BEGIN INITIAL;
     return ID_COLON;


@@ -313,7 +300,7 @@ splice       (\\[ \f\t\v]*\n)*
 {
   "*/"     BEGIN context_state;
   .|\n    ;
 {
   "*/"     BEGIN context_state;
   .|\n    ;

-  <<EOF>>  unexpected_end_of_file (token_start, "*/");
+  <<EOF>>  unexpected_eof (token_start, "*/"); BEGIN context_state;

 }
 
 
 }
 
 


@@ -324,7 +311,7 @@ splice       (\\[ \f\t\v]*\n)*
 <SC_COMMENT>
 {
   "*"{splice}"/"  STRING_GROW; BEGIN context_state;
 <SC_COMMENT>
 {
   "*"{splice}"/"  STRING_GROW; BEGIN context_state;

-  <<EOF>>        unexpected_end_of_file (token_start, "*/");
+  <<EOF>>        unexpected_eof (token_start, "*/"); BEGIN context_state;

 }
 
 
 }
 
 


@@ -340,51 +327,67 @@ splice     (\\[ \f\t\v]*\n)*
 }
 
 
 }
 
 

-  /*----------------------------------------------------------------.
-  | Scanning a C string, including its escapes.  The initial `"' is |
-  | already eaten.                                                  |
-  `----------------------------------------------------------------*/
+  /*------------------------------------------------.
+  | Scanning a Bison string, including its escapes. |
+  | The initial quote is already eaten.             |
+  `------------------------------------------------*/

 
 <SC_ESCAPED_STRING>
 {
 
 <SC_ESCAPED_STRING>
 {

-  "\"" {
-    STRING_GROW;
+  "\""|"\n" {
+    if (yytext[0] == '\n')
+      unexpected_newline (token_start, "\"");
+    STRING_FINISH;
+    loc->start = token_start;
+    val->chars = last_string;
+    BEGIN INITIAL;
+    return STRING;
+  }
+  <<EOF>> {
+    unexpected_eof (token_start, "\"");

     STRING_FINISH;
     loc->start = token_start;
     val->chars = last_string;
     STRING_FINISH;
     loc->start = token_start;
     val->chars = last_string;

-    rule_length++;

     BEGIN INITIAL;
     return STRING;
   }
     BEGIN INITIAL;
     return STRING;
   }

-
-  .|\n     STRING_GROW;
-  <<EOF>>   unexpected_end_of_file (token_start, "\"");

 }
 
 }
 

-  /*---------------------------------------------------------------.
-  | Scanning a C character, decoding its escapes.  The initial "'" |
-  | is already eaten.                                              |
-  `---------------------------------------------------------------*/
+  /*----------------------------------------------------------.
+  | Scanning a Bison character literal, decoding its escapes. |
+  | The initial quote is already eaten.                              |
+  `----------------------------------------------------------*/

 
 <SC_ESCAPED_CHARACTER>
 {
 
 <SC_ESCAPED_CHARACTER>
 {

-  "'" {
-    unsigned char last_string_1;
+  "'"|"\n" {
+    if (yytext[0] == '\n')
+      unexpected_newline (token_start, "'");

     STRING_GROW;
     STRING_FINISH;
     loc->start = token_start;
     STRING_GROW;
     STRING_FINISH;
     loc->start = token_start;

-    val->symbol = symbol_get (last_string, *loc);
-    symbol_class_set (val->symbol, token_sym, *loc);
-    last_string_1 = last_string[1];
-    symbol_user_token_number_set (val->symbol, last_string_1, *loc);
+    val->character = last_string[1];

     STRING_FREE;
     STRING_FREE;

-    rule_length++;

     BEGIN INITIAL;
     BEGIN INITIAL;

-    return ID;
+    return CHAR;

   }
   }

+  <<EOF>> {
+    unexpected_eof (token_start, "'");
+    STRING_FINISH;
+    loc->start = token_start;
+    if (strlen(last_string) > 1)
+      val->character = last_string[1];
+    else
+      val->character = last_string[0];
+    STRING_FREE;
+    BEGIN INITIAL;
+    return CHAR;
+  }
+}

 
 

-  .|\n     STRING_GROW;
-  <<EOF>>   unexpected_end_of_file (token_start, "'");
+<SC_ESCAPED_CHARACTER,SC_ESCAPED_STRING>
+{
+  \0       complain_at (*loc, _("invalid null character"));

 }
 
 
 }
 
 


@@ -395,19 +398,22 @@ splice     (\\[ \f\t\v]*\n)*
 <SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>
 {
   \\[0-7]{1,3} {
 <SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>
 {
   \\[0-7]{1,3} {

-    unsigned long c = strtoul (yytext + 1, 0, 8);
+    unsigned long int c = strtoul (yytext + 1, NULL, 8);

     if (UCHAR_MAX < c)
       complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
     if (UCHAR_MAX < c)
       complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));

+    else if (! c)
+      complain_at (*loc, _("invalid null character: %s"), quote (yytext));

     else
       obstack_1grow (&obstack_for_string, c);
   }
 
   \\x[0-9abcdefABCDEF]+ {
     else
       obstack_1grow (&obstack_for_string, c);
   }
 
   \\x[0-9abcdefABCDEF]+ {

-    unsigned long c;
-    set_errno (0);
-    c = strtoul (yytext + 2, 0, 16);
-    if (UCHAR_MAX < c || get_errno ())
+    verify (UCHAR_MAX < ULONG_MAX);
+    unsigned long int c = strtoul (yytext + 2, NULL, 16);
+    if (UCHAR_MAX < c)

       complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
       complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));

+    else if (! c)
+      complain_at (*loc, _("invalid null character: %s"), quote (yytext));

     else
       obstack_1grow (&obstack_for_string, c);
   }
     else
       obstack_1grow (&obstack_for_string, c);
   }


@@ -427,6 +433,8 @@ splice       (\\[ \f\t\v]*\n)*
     int c = convert_ucn_to_byte (yytext);
     if (c < 0)
       complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
     int c = convert_ucn_to_byte (yytext);
     if (c < 0)
       complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));

+    else if (! c)
+      complain_at (*loc, _("invalid null character: %s"), quote (yytext));

     else
       obstack_1grow (&obstack_for_string, c);
   }
     else
       obstack_1grow (&obstack_for_string, c);
   }


@@ -436,30 +444,27 @@ splice     (\\[ \f\t\v]*\n)*
   }
 }
 
   }
 }
 

+  /*--------------------------------------------.
+  | Scanning user-code characters and strings.  |
+  `--------------------------------------------*/

 
 

-  /*----------------------------------------------------------.
-  | Scanning a C character without decoding its escapes.  The |
-  | initial "'" is already eaten.                             |
-  `----------------------------------------------------------*/
+<SC_CHARACTER,SC_STRING>
+{
+  {splice}|\\{splice}[^\n\[\]] STRING_GROW;
+}

 
 <SC_CHARACTER>
 {
 
 <SC_CHARACTER>
 {

-  "'"                  STRING_GROW; BEGIN context_state;
-  \\{splice}[^$@\[\]]  STRING_GROW;
-  <<EOF>>              unexpected_end_of_file (token_start, "'");
+  "'"          STRING_GROW; BEGIN context_state;
+  \n           unexpected_newline (token_start, "'"); BEGIN context_state;
+  <<EOF>>      unexpected_eof (token_start, "'"); BEGIN context_state;

 }
 
 }
 

-
-  /*----------------------------------------------------------------.
-  | Scanning a C string, without decoding its escapes.  The initial |
-  | `"' is already eaten.                                           |
-  `----------------------------------------------------------------*/
-

 <SC_STRING>
 {
 <SC_STRING>
 {

-  "\""                 STRING_GROW; BEGIN context_state;
-  \\{splice}[^$@\[\]]  STRING_GROW;
-  <<EOF>>              unexpected_end_of_file (token_start, "\"");
+  "\""         STRING_GROW; BEGIN context_state;
+  \n           unexpected_newline (token_start, "\""); BEGIN context_state;
+  <<EOF>>      unexpected_eof (token_start, "\""); BEGIN context_state;

 }
 
 
 }
 
 


@@ -495,24 +500,25 @@ splice     (\\[ \f\t\v]*\n)*
 }
 
 
 }
 
 

-  /*---------------------------------------------------------------.
-  | Scanning some code in braces (%union and actions). The initial |
-  | "{" is already eaten.                                          |
-  `---------------------------------------------------------------*/
+
+  /*-----------------------------------------------------------.
+  | Scanning some code in braces (actions). The initial "{" is |
+  | already eaten.                                             |
+  `-----------------------------------------------------------*/

 
 <SC_BRACED_CODE>
 {
   "{"|"<"{splice}"%"  STRING_GROW; braces_level++;
   "%"{splice}">"      STRING_GROW; braces_level--;
   "}" {
 
 <SC_BRACED_CODE>
 {
   "{"|"<"{splice}"%"  STRING_GROW; braces_level++;
   "%"{splice}">"      STRING_GROW; braces_level--;
   "}" {

-    STRING_GROW;
-    braces_level--;
+    obstack_1grow (&obstack_for_string, '}');
+
+    --braces_level;

     if (braces_level < 0)
       {
        STRING_FINISH;
        loc->start = code_start;
     if (braces_level < 0)
       {
        STRING_FINISH;
        loc->start = code_start;

-       val->chars = last_string;
-       rule_length++;
+       val->code = last_string;

        BEGIN INITIAL;
        return BRACED_CODE;
       }
        BEGIN INITIAL;
        return BRACED_CODE;
       }


@@ -522,12 +528,14 @@ splice     (\\[ \f\t\v]*\n)*
      (as `<' `<%').  */
   "<"{splice}"<"  STRING_GROW;
 
      (as `<' `<%').  */
   "<"{splice}"<"  STRING_GROW;
 

-  "$"("<"{tag}">")?(-?[0-9]+|"$") { handle_dollar (current_braced_code,
-                                                  yytext, *loc); }
-  "@"(-?[0-9]+|"$")               { handle_at (current_braced_code,
-                                              yytext, *loc); }
-
-  <<EOF>>  unexpected_end_of_file (code_start, "}");
+  <<EOF>> {
+    unexpected_eof (code_start, "}");
+    STRING_FINISH;
+    loc->start = code_start;
+    val->code = last_string;
+    BEGIN INITIAL;
+    return BRACED_CODE;
+  }

 }
 
 
 }
 
 


@@ -545,7 +553,14 @@ splice      (\\[ \f\t\v]*\n)*
     return PROLOGUE;
   }
 
     return PROLOGUE;
   }
 

-  <<EOF>>  unexpected_end_of_file (code_start, "%}");
+  <<EOF>> {
+    unexpected_eof (code_start, "%}");
+    STRING_FINISH;
+    loc->start = code_start;
+    val->chars = last_string;
+    BEGIN INITIAL;
+    return PROLOGUE;
+  }

 }
 
 
 }
 
 


@@ -566,60 +581,15 @@ splice     (\\[ \f\t\v]*\n)*
 }
 
 
 }
 
 

-  /*----------------------------------------------------------------.
-  | By default, grow the string obstack with the input, escaping M4 |
-  | quoting characters.                                                    |
-  `----------------------------------------------------------------*/
-
-<SC_COMMENT,SC_LINE_COMMENT,SC_STRING,SC_CHARACTER,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>
-{
-  \$   obstack_sgrow (&obstack_for_string, "$][");
-  \@   obstack_sgrow (&obstack_for_string, "@@");
-  \[   obstack_sgrow (&obstack_for_string, "@{");
-  \]   obstack_sgrow (&obstack_for_string, "@}");
-  .|\n  STRING_GROW;
-}
+  /*-----------------------------------------------------.
+  | By default, grow the string obstack with the input.  |
+  `-----------------------------------------------------*/

 
 

+<SC_COMMENT,SC_LINE_COMMENT,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE,SC_STRING,SC_CHARACTER,SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>.     |
+<SC_COMMENT,SC_LINE_COMMENT,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>\n  STRING_GROW;

 
 %%
 
 
 %%
 

-/* Set *LOC and adjust scanner cursor to account for token TOKEN of
-   size SIZE.  */
-
-static void
-adjust_location (location *loc, char const *token, size_t size)
-{
-  int line = scanner_cursor.line;
-  int column = scanner_cursor.column;
-  char const *p0 = token;
-  char const *p = token;
-  char const *lim = token + size;
-
-  loc->start = scanner_cursor;
-
-  for (p = token; p < lim; p++)
-    switch (*p)
-      {
-      case '\n':
-       line++;
-       column = 1;
-       p0 = p + 1;
-       break;
-
-      case '\t':
-       column += mbsnwidth (p0, p - p0, 0);
-       column += 8 - ((column - 1) & 7);
-       p0 = p + 1;
-       break;
-      }
-
-  scanner_cursor.line = line;
-  scanner_cursor.column = column + mbsnwidth (p0, p - p0, 0);
-
-  loc->end = scanner_cursor;
-}
-
-

 /* Read bytes from FP into buffer BUF of size SIZE.  Return the
    number of bytes read.  Remove '\r' from input, treating \r\n
    and isolated \r as \n.  */
 /* Read bytes from FP into buffer BUF of size SIZE.  Return the
    number of bytes read.  Remove '\r' from input, treating \r\n
    and isolated \r as \n.  */


@@ -627,14 +597,14 @@ adjust_location (location *loc, char const *token, size_t size)
 static size_t
 no_cr_read (FILE *fp, char *buf, size_t size)
 {
 static size_t
 no_cr_read (FILE *fp, char *buf, size_t size)
 {

-  size_t s = fread (buf, 1, size, fp);
-  if (s)
+  size_t bytes_read = fread (buf, 1, size, fp);
+  if (bytes_read)

     {
     {

-      char *w = memchr (buf, '\r', s);
+      char *w = memchr (buf, '\r', bytes_read);

       if (w)
        {
          char const *r = ++w;
       if (w)
        {
          char const *r = ++w;

-         char const *lim = buf + s;
+         char const *lim = buf + bytes_read;

 
          for (;;)
            {
 
          for (;;)
            {


@@ -663,178 +633,28 @@ no_cr_read (FILE *fp, char *buf, size_t size)
        }
     }
 
        }
     }
 

-  return s;
-}
-
-
-/*------------------------------------------------------------------.
-| TEXT is pointing to a wannabee semantic value (i.e., a `$').      |
-|                                                                   |
-| Possible inputs: $[<TYPENAME>]($|integer)                         |
-|                                                                   |
-| Output to OBSTACK_FOR_STRING a reference to this semantic value.  |
-`------------------------------------------------------------------*/
-
-static inline void
-handle_action_dollar (char *text, location loc)
-{
-  const char *type_name = NULL;
-  char *cp = text + 1;
-
-  /* Get the type name if explicit. */
-  if (*cp == '<')
-    {
-      type_name = ++cp;
-      while (*cp != '>')
-       ++cp;
-      *cp = '\0';
-      ++cp;
-    }
-
-  if (*cp == '$')
-    {
-      if (!type_name)
-       type_name = symbol_list_n_type_name_get (current_rule, loc, 0);
-      if (!type_name && typed)
-       complain_at (loc, _("$$ of `%s' has no declared type"),
-                    current_rule->sym->tag);
-      if (!type_name)
-       type_name = "";
-      obstack_fgrow1 (&obstack_for_string,
-                     "]b4_lhs_value([%s])[", type_name);
-    }
-  else
-    {
-      long num;
-      set_errno (0);
-      num = strtol (cp, 0, 10);
-
-      if (INT_MIN <= num && num <= rule_length && ! get_errno ())
-       {
-         int n = num;
-         if (!type_name && n > 0)
-           type_name = symbol_list_n_type_name_get (current_rule, loc, n);
-         if (!type_name && typed)
-           complain_at (loc, _("$%d of `%s' has no declared type"),
-                        n, current_rule->sym->tag);
-         if (!type_name)
-           type_name = "";
-         obstack_fgrow3 (&obstack_for_string,
-                         "]b4_rhs_value([%d], [%d], [%s])[",
-                         rule_length, n, type_name);
-       }
-      else
-       complain_at (loc, _("integer out of range: %s"), quote (text));
-    }
-}
-
-
-/*---------------------------------------------------------------.
-| TEXT is expected to be $$ in some code associated to a symbol: |
-| destructor or printer.                                         |
-`---------------------------------------------------------------*/
-
-static inline void
-handle_symbol_code_dollar (char *text, location loc)
-{
-  char *cp = text + 1;
-  if (*cp == '$')
-    obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
-  else
-    complain_at (loc, _("invalid value: %s"), quote (text));
+  return bytes_read;

 }
 
 
 }
 
 

-/*-----------------------------------------------------------------.
-| Dispatch onto handle_action_dollar, or handle_destructor_dollar, |
-| depending upon CODE_KIND.                                        |
-`-----------------------------------------------------------------*/
-
-static void
-handle_dollar (braced_code braced_code_kind, char *text, location loc)
-{
-  switch (braced_code_kind)
-    {
-    case action_braced_code:
-      handle_action_dollar (text, loc);
-      break;
-
-    case destructor_braced_code:
-    case printer_braced_code:
-      handle_symbol_code_dollar (text, loc);
-      break;
-    }
-}
-

 
 /*------------------------------------------------------.
 
 /*------------------------------------------------------.

-| TEXT is a location token (i.e., a `@...').  Output to |
-| OBSTACK_FOR_STRING a reference to this location.      |
+| Scan NUMBER for a base-BASE integer at location LOC.  |

 `------------------------------------------------------*/
 
 `------------------------------------------------------*/
 

-static inline void
-handle_action_at (char *text, location loc)
+static unsigned long int
+scan_integer (char const *number, int base, location loc)

 {
 {

-  char *cp = text + 1;
-  locations_flag = 1;
+  verify (INT_MAX < ULONG_MAX);
+  unsigned long int num = strtoul (number, NULL, base);

 
 

-  if (*cp == '$')
+  if (INT_MAX < num)

     {
     {

-      obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
+      complain_at (loc, _("integer out of range: %s"), quote (number));
+      num = INT_MAX;

     }
     }

-  else
-    {
-      long num;
-      set_errno (0);
-      num = strtol (cp, 0, 10);

 
 

-      if (INT_MIN <= num && num <= rule_length && ! get_errno ())
-       {
-         int n = num;
-         obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location([%d], [%d])[",
-                         rule_length, n);
-       }
-      else
-       complain_at (loc, _("integer out of range: %s"), quote (text));
-    }
-}
-
-
-/*---------------------------------------------------------------.
-| TEXT is expected to be @$ in some code associated to a symbol: |
-| destructor or printer.                                         |
-`---------------------------------------------------------------*/
-
-static inline void
-handle_symbol_code_at (char *text, location loc)
-{
-  char *cp = text + 1;
-  if (*cp == '$')
-    obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
-  else
-    complain_at (loc, _("invalid value: %s"), quote (text));
-}
-
-
-/*-------------------------------------------------------------------.
-| Dispatch onto handle_action_at, or handle_destructor_at, depending |
-| upon CODE_KIND.                                                    |
-`-------------------------------------------------------------------*/
-
-static void
-handle_at (braced_code braced_code_kind, char *text, location loc)
-{
-  switch (braced_code_kind)
-    {
-    case action_braced_code:
-      handle_action_at (text, loc);
-      break;
-
-    case destructor_braced_code:
-    case printer_braced_code:
-      handle_symbol_code_at (text, loc);
-      break;
-    }
+  return num;

 }
 
 
 }
 
 


@@ -847,7 +667,8 @@ handle_at (braced_code braced_code_kind, char *text, location loc)
 static int
 convert_ucn_to_byte (char const *ucn)
 {
 static int
 convert_ucn_to_byte (char const *ucn)
 {

-  unsigned long code = strtoul (ucn + 2, 0, 16);
+  verify (UCHAR_MAX <= INT_MAX);
+  unsigned long int code = strtoul (ucn + 2, NULL, 16);

 
   /* FIXME: Currently we assume Unicode-compatible unibyte characters
      on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes).  On
 
   /* FIXME: Currently we assume Unicode-compatible unibyte characters
      on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes).  On


@@ -899,40 +720,58 @@ convert_ucn_to_byte (char const *ucn)
 `----------------------------------------------------------------*/
 
 static void
 `----------------------------------------------------------------*/
 
 static void

-handle_syncline (char *args)
+handle_syncline (char *args, location loc)

 {
 {

-  int lineno = strtol (args, &args, 10);
-  const char *file = NULL;
-  file = strchr (args, '"') + 1;
-  *strchr (file, '"') = 0;
-  scanner_cursor.file = current_file = xstrdup (file);
-  scanner_cursor.line = lineno;
-  scanner_cursor.column = 1;
+  char *after_num;
+  unsigned long int lineno = strtoul (args, &after_num, 10);
+  char *file = strchr (after_num, '"') + 1;
+  *strchr (file, '"') = '\0';
+  if (INT_MAX <= lineno)
+    {
+      warn_at (loc, _("line number overflow"));
+      lineno = INT_MAX;
+    }
+  current_file = uniqstr_new (file);
+  boundary_set (&scanner_cursor, current_file, lineno, 1);
+}
+
+
+/*----------------------------------------------------------------.
+| For a token or comment starting at START, report message MSGID, |
+| which should say that an end marker was found before           |
+| the expected TOKEN_END.                                        |
+`----------------------------------------------------------------*/
+
+static void
+unexpected_end (boundary start, char const *msgid, char const *token_end)
+{
+  location loc;
+  loc.start = start;
+  loc.end = scanner_cursor;
+  complain_at (loc, _(msgid), token_end);

 }
 
 
 /*------------------------------------------------------------------------.
 | Report an unexpected EOF in a token or comment starting at START.       |
 | An end of file was encountered and the expected TOKEN_END was missing.  |
 }
 
 
 /*------------------------------------------------------------------------.
 | Report an unexpected EOF in a token or comment starting at START.       |
 | An end of file was encountered and the expected TOKEN_END was missing.  |

-| After reporting the problem, pretend that TOKEN_END was found.          |

 `------------------------------------------------------------------------*/
 
 static void
 `------------------------------------------------------------------------*/
 
 static void

-unexpected_end_of_file (boundary start, char const *token_end)
+unexpected_eof (boundary start, char const *token_end)

 {
 {

-  size_t i = strlen (token_end);
+  unexpected_end (start, N_("missing `%s' at end of file"), token_end);
+}

 
 

-  location loc;
-  loc.start = start;
-  loc.end = scanner_cursor;
-  complain_at (loc, _("missing `%s' at end of file"), token_end);

 
 

-  /* Adjust scanner cursor so that any later message does not count
-     the characters about to be inserted.  */
-  scanner_cursor.column -= i;
+/*----------------------------------------.
+| Likewise, but for unexpected newlines.  |
+`----------------------------------------*/

 
 

-  while (i != 0)
-    unput (token_end[--i]);
+static void
+unexpected_newline (boundary start, char const *token_end)
+{
+  unexpected_end (start, N_("missing `%s' at end of line"), token_end);

 }
 
 
 }
 
 


@@ -941,7 +780,7 @@ unexpected_end_of_file (boundary start, char const *token_end)
 `-------------------------*/
 
 void
 `-------------------------*/
 
 void

-scanner_initialize (void)
+gram_scanner_initialize (void)

 {
   obstack_init (&obstack_for_string);
 }
 {
   obstack_init (&obstack_for_string);
 }


@@ -952,9 +791,9 @@ scanner_initialize (void)
 `-----------------------------------------------*/
 
 void
 `-----------------------------------------------*/
 
 void

-scanner_free (void)
+gram_scanner_free (void)

 {
   obstack_free (&obstack_for_string, 0);
   /* Reclaim Flex's buffers.  */
 {
   obstack_free (&obstack_for_string, 0);
   /* Reclaim Flex's buffers.  */

-  yy_delete_buffer (YY_CURRENT_BUFFER);
+  yylex_destroy ();

 }
 }