bison/src/scan-skel.l

/* Scan Bison Skeletons.                                       -*- C -*-

   Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
   2010 Free Software Foundation, Inc.

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

   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
   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,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   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, see <http://www.gnu.org/licenses/>.  */

%option nodefault noyywrap noinput nounput never-interactive debug
%option prefix="skel_" outfile="lex.yy.c"

%{
/* Work around a bug in flex 2.5.31.  See Debian bug 333231
   <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
#undef skel_wrap
#define skel_wrap() 1

#define FLEX_PREFIX(Id) skel_ ## Id
#include <src/flex-scanner.h>

#include <dirname.h>
#include <error.h>
#include <quotearg.h>

#include <src/complain.h>
#include <src/getargs.h>
#include <src/files.h>
#include <src/scan-skel.h>

#define YY_DECL static int skel_lex (void)
YY_DECL;

#define QPUTS(String) \
   fputs (quotearg_style (c_quoting_style, String), yyout)

static void at_directive_perform (int at_directive_argc,
                                  char *at_directive_argv[],
                                  char **outnamep, int *out_linenop);
static void fail_for_at_directive_too_many_args (char const *at_directive_name);
static void fail_for_at_directive_too_few_args (char const *at_directive_name);
static void fail_for_invalid_at (char const *at);
%}

%x SC_AT_DIRECTIVE_ARGS
%x SC_AT_DIRECTIVE_SKIP_WS

%%

%{
  int out_lineno IF_LINT (= 0);
  char *outname = NULL;

  /* Currently, only the @warn, @complain, @fatal, @warn_at, @complain_at, and
     @fatal_at directives take multiple arguments, and the last three already
     can't take more than 7.  at_directive_argv[0] is the directive name.  */
  #define AT_DIRECTIVE_ARGC_MAX 8
  int at_directive_argc = 0;
  char *at_directive_argv[AT_DIRECTIVE_ARGC_MAX];
%}

"@@" fputc ('@', yyout);
"@{" fputc ('[', yyout);
"@}" fputc (']', yyout);
"@`" /* Emtpy.  Used by b4_cat in ../data/bison.m4.  */
@\n  /* Likewise.  */

"@oline@"  fprintf (yyout, "%d", out_lineno + 1);
"@ofile@"  QPUTS (outname);
"@dir_prefix@" QPUTS (dir_prefix);

@[a-z_]+"(" {
  yytext[yyleng-1] = '\0';
  obstack_grow (&obstack_for_string, yytext, yyleng);
  at_directive_argv[at_directive_argc++] =
    obstack_finish (&obstack_for_string);
  BEGIN SC_AT_DIRECTIVE_ARGS;
}

  /* This pattern must not match more than the previous @ patterns. */
@[^@{}`(\n]* fail_for_invalid_at (yytext);
\n	   out_lineno++; ECHO;
[^@\n]+	   ECHO;

<INITIAL><<EOF>> {
  if (outname)
    {
      free (outname);
      xfclose (yyout);
    }
  return EOF;
}

<SC_AT_DIRECTIVE_ARGS>{
  [^@]+ { STRING_GROW; }

  "@@" { obstack_1grow (&obstack_for_string, '@'); }
  "@{" { obstack_1grow (&obstack_for_string, '['); }
  "@}" { obstack_1grow (&obstack_for_string, ']'); }
  "@`" /* Empty.  Useful for starting an argument
          that begins with whitespace. */
  @\n  /* Empty.  */

  @[,)] {
    if (at_directive_argc >= AT_DIRECTIVE_ARGC_MAX)
      fail_for_at_directive_too_many_args (at_directive_argv[0]);

    obstack_1grow (&obstack_for_string, '\0');
    at_directive_argv[at_directive_argc++] =
      obstack_finish (&obstack_for_string);

    /* Like M4, skip whitespace after a comma.  */
    if (yytext[1] == ',')
      BEGIN SC_AT_DIRECTIVE_SKIP_WS;
    else
      {
        at_directive_perform (at_directive_argc, at_directive_argv,
                              &outname, &out_lineno);
        obstack_free (&obstack_for_string, at_directive_argv[0]);
        at_directive_argc = 0;
        BEGIN INITIAL;
      }
  }

  @.? { fail_for_invalid_at (yytext); }
}

<SC_AT_DIRECTIVE_SKIP_WS>{
  [ \t\r\n]
  . { yyless (0); BEGIN SC_AT_DIRECTIVE_ARGS; }
}

<SC_AT_DIRECTIVE_ARGS,SC_AT_DIRECTIVE_SKIP_WS>{
  <<EOF>> {
    fatal (_("unclosed %s directive in skeleton"), at_directive_argv[0]);
  }
}

%%

/*------------------------.
| Scan a Bison skeleton.  |
`------------------------*/

void
scan_skel (FILE *in)
{
  static bool initialized = false;
  if (!initialized)
    {
      initialized = true;
      obstack_init (&obstack_for_string);
    }
  skel_in = in;
  skel__flex_debug = trace_flag & trace_skeleton;
  skel_lex ();
}

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

static void
at_directive_perform (int at_directive_argc,
                      char *at_directive_argv[],
                      char **outnamep, int *out_linenop)
{
  if (0 == strcmp (at_directive_argv[0], "@basename"))
    {
      if (at_directive_argc > 2)
        fail_for_at_directive_too_many_args (at_directive_argv[0]);
      fputs (last_component (at_directive_argv[1]), yyout);
    }
  else if (0 == strcmp (at_directive_argv[0], "@warn")
           || 0 == strcmp (at_directive_argv[0], "@complain")
           || 0 == strcmp (at_directive_argv[0], "@fatal"))
    {
      void (*func)(char const *, ...);
      switch (at_directive_argv[0][1])
        {
          case 'w': func = warn; break;
          case 'c': func = complain; break;
          case 'f': func = fatal; break;
          default: aver (false); break;
        }
      switch (at_directive_argc)
        {
          case 2:
            func (_(at_directive_argv[1]));
            break;
          case 3:
            func (_(at_directive_argv[1]), at_directive_argv[2]);
            break;
          case 4:
            func (_(at_directive_argv[1]), at_directive_argv[2],
                  at_directive_argv[3]);
            break;
          case 5:
            func (_(at_directive_argv[1]), at_directive_argv[2],
                  at_directive_argv[3], at_directive_argv[4]);
            break;
          case 6:
            func (_(at_directive_argv[1]), at_directive_argv[2],
                  at_directive_argv[3], at_directive_argv[4],
                  at_directive_argv[5]);
            break;
          default:
            fail_for_at_directive_too_many_args (at_directive_argv[0]);
            break;
        }
    }
  else if (0 == strcmp (at_directive_argv[0], "@warn_at")
           || 0 == strcmp (at_directive_argv[0], "@complain_at")
           || 0 == strcmp (at_directive_argv[0], "@fatal_at"))
    {
      void (*func)(location, char const *, ...);
      location loc;
      if (at_directive_argc < 4)
        fail_for_at_directive_too_few_args (at_directive_argv[0]);
      switch (at_directive_argv[0][1])
        {
          case 'w': func = warn_at; break;
          case 'c': func = complain_at; break;
          case 'f': func = fatal_at; break;
          default: aver (false); break;
        }
      boundary_set_from_string (&loc.start, at_directive_argv[1]);
      boundary_set_from_string (&loc.end, at_directive_argv[2]);
      switch (at_directive_argc)
        {
          case 4:
            func (loc, _(at_directive_argv[3]));
            break;
          case 5:
            func (loc, _(at_directive_argv[3]), at_directive_argv[4]);
            break;
          case 6:
            func (loc, _(at_directive_argv[3]), at_directive_argv[4],
                  at_directive_argv[5]);
            break;
          case 7:
            func (loc, _(at_directive_argv[3]), at_directive_argv[4],
                  at_directive_argv[5], at_directive_argv[6]);
            break;
          case 8:
            func (loc, _(at_directive_argv[3]), at_directive_argv[4],
                  at_directive_argv[5], at_directive_argv[6],
                  at_directive_argv[7]);
            break;
          default:
            fail_for_at_directive_too_many_args (at_directive_argv[0]);
            break;
        }
    }
  else if (0 == strcmp (at_directive_argv[0], "@output"))
    {
      if (at_directive_argc > 2)
        fail_for_at_directive_too_many_args (at_directive_argv[0]);
      if (*outnamep)
        {
          free (*outnamep);
          xfclose (yyout);
        }
      *outnamep = xstrdup (at_directive_argv[1]);
      output_file_name_check (outnamep);
      yyout = xfopen (*outnamep, "w");
      *out_linenop = 1;
    }
  else
    fail_for_invalid_at (at_directive_argv[0]);
}

static void
fail_for_at_directive_too_few_args (char const *at_directive_name)
{
  fatal (_("too few arguments for %s directive in skeleton"),
         at_directive_name);
}

static void
fail_for_at_directive_too_many_args (char const *at_directive_name)
{
  fatal (_("too many arguments for %s directive in skeleton"),
         at_directive_name);
}

static void
fail_for_invalid_at (char const *at)
{
  fatal ("invalid @ in skeleton: %s", at);
}