src/ldlex.l

%{
/* Copyright (C) 2001, 2002, 2003, 2004, 2005, 2008 Red Hat, Inc.
   This file is part of Red Hat elfutils.
   Written by Ulrich Drepper <drepper@redhat.com>, 2001.

   Red Hat elfutils 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; version 2 of the License.

   Red Hat elfutils 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 Red Hat elfutils; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

   Red Hat elfutils is an included package of the Open Invention Network.
   An included package of the Open Invention Network is a package for which
   Open Invention Network licensees cross-license their patents.  No patent
   license is granted, either expressly or impliedly, by designation as an
   included package.  Should you wish to participate in the Open Invention
   Network licensing program, please visit www.openinventionnetwork.com
   <http://www.openinventionnetwork.com>.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <assert.h>
#include <ctype.h>
#include <elf.h>
#include <error.h>
#include <inttypes.h>
#include <libintl.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>

#include <system.h>
#include <ld.h>
#include "ldscript.h"

/* We sure use no threads to read the stream, so use the _unlocked
   variants of the functions.  */
#undef getc
#define getc(s) getc_unlocked (s)
#undef ferror
#define ferror(s) ferror_unlocked (s)
#undef fread
#define fread(b, m, n, s) fread_unlocked (b, m, n, s)
#undef fwrite
#define fwrite(b, m, n, s) fwrite_unlocked (b, m, n, s)

/* ECHO must be redefined since the default implementation ignores
   the return value of fwrite_unlocked.  */
#define ECHO do { size_t n__ __attribute__ ((unused)) \
			   = fwrite (yytext, yyleng, 1, yyout); } while (0)

/* Defined in ld.c.  */
extern int ld_scan_version_script;

#define MAX_PREPDEPTH 20
static enum prepstate
{
  prep_normal,
  skip_if,
  skip_to_endif
} prepstate[MAX_PREPDEPTH];
static int prepdepth;

static void eat_comment (void);
static void eat_to_eol (bool empty);
static int attrib_convert (int c);
static void push_state (enum prepstate);
static int pop_state (void);
static int handle_ifdef (void);
static void invalid_char (int ch);
%}

ID		[a-zA-Z0-9_.*?][a-zA-Z0-9_.*?-]*
FILENAMECHAR1	[a-zA-Z0-9_/.\\~]
FILENAMECHAR	[^][{}[:space:]():;]+
HEX		0[xX][0-9a-fA-F]+[kKmM]?
OCT		0[0-7]*[kKmM]?
DEC		[0-9]+[kKmM]?
WHITE		[[:space:]]+

%option yylineno
%option never-interactive
%option noyywrap

%x IGNORE

%%
				if (unlikely (ld_scan_version_script))
				  {
				    ld_scan_version_script = -1;
				    return kVERSION_SCRIPT;
				  }

^"#"ifdef/[[:space:]]		{ BEGIN (handle_ifdef ()); }
^"#"else/[[:space:]\n]		{ eat_to_eol (true);
				  push_state (skip_to_endif);
				  BEGIN (IGNORE); }
^"#"elifdef/[[:space:]]		{ eat_to_eol (false);
				  push_state (skip_to_endif);
				  BEGIN (IGNORE); }
^"#"endif/[[:space:]\n]		{ eat_to_eol (true) ; }

<IGNORE>^"#"ifdef/[[:space:]\n] { eat_to_eol (false);
				  push_state (skip_to_endif); }
<IGNORE>^"#"else/[[:space:]\n]	{ eat_to_eol (true);
				  assert (prepdepth > 0);
				  if (prepstate[prepdepth - 1] == skip_if)
				    {
				      /* Back to normal processing.  */
				      assert (prepdepth == 1);
				      BEGIN (pop_state ());
				    }
				}
<IGNORE>^"#"elifdef/[[:space:]]	{ assert (prepdepth > 0);
				  if (prepstate[prepdepth - 1] == skip_if)
				    {
				      /* Maybe this symbol is defined.  */
				      pop_state ();
				      BEGIN (handle_ifdef ());
				    }
				}
<IGNORE>^"#"endif/[[:space:]\n] { eat_to_eol (true);
				  BEGIN (pop_state ()); }
<IGNORE>.|\n			{ /* nothing */ }


"/*"				{ eat_comment (); }

ALIGN				{ return kALIGN; }
AS_NEEDED			{ return kAS_NEEDED; }
ENTRY				{ return kENTRY; }
EXCLUDE_FILE			{ return kEXCLUDE_FILE; }
"global:"			{ return kGLOBAL; }
GROUP				{ return kGROUP; }
INPUT				{ return kINPUT; }
INTERP				{ return kINTERP; }
KEEP				{ return kKEEP; }
"local:"			{ return kLOCAL; }
OUTPUT_FORMAT			{ return kOUTPUT_FORMAT; }
PAGESIZE			{ return kPAGESIZE; }
PROVIDE				{ return kPROVIDE; }
SEARCH_DIR			{ return kSEARCH_DIR; }
SEGMENT				{ return kSEGMENT; }
SIZEOF_HEADERS			{ return kSIZEOF_HEADERS; }
SORT				{ return kSORT; }
VERSION				{ return kVERSION; }

"["([RWX]){0,3}"]"		{ int cnt = 1 ;
				  ldlval.num = 0;
				  while (cnt < yyleng - 1)
				    ldlval.num |= attrib_convert (yytext[cnt++]);
				  return kMODE; }

"{"				{ return '{'; }
"}"				{ return '}'; }
"("				{ return '('; }
")"				{ return ')'; }
":"				{ return ':'; }
";"				{ return ';'; }
"="				{ return '='; }
"+"				{ ldlval.op = exp_plus; return kADD_OP; }
"-"				{ ldlval.op = exp_minus; return kADD_OP; }
"*"				{ return '*'; }
"/"				{ ldlval.op = exp_div; return kMUL_OP; }
"%"				{ ldlval.op = exp_mod; return kMUL_OP; }
"&"				{ return '&'; }
"|"				{ return '|'; }

","				{ return ','; }

{HEX}|{OCT}|{DEC}		{ char *endp;
				  ldlval.num = strtoumax (yytext, &endp, 0);
				  if (*endp != '\0')
				    {
				      if (tolower (*endp) == 'k')
					ldlval.num *= 1024;
				      else
					{
					  assert (tolower (*endp) == 'm');
					  ldlval.num *= 1024 * 1024;
					}
				    }
				  return kNUM; }

{ID}				{ ldlval.str = obstack_strndup (&ld_state.smem,
								yytext, yyleng);
				  return kID; }

{FILENAMECHAR1}{FILENAMECHAR}	{ ldlval.str = obstack_strndup (&ld_state.smem,
								yytext, yyleng);
				  return kFILENAME; }

{WHITE}				{ /* IGNORE */ }

.				{ invalid_char (*yytext); }

%%

static void
eat_comment (void)
{
  while (1)
    {
      int c = input ();

      while (c != '*' && c != EOF)
	c = input ();

      if (c == '*')
	{
	  c = input ();
	  while (c == '*')
	    c = input ();
	  if (c == '/')
	    break;
	}

      if (c == EOF)
	{
	  /* XXX Use the setjmp buffer and signal EOF in comment */
	  error (0, 0, gettext ("EOF in comment"));
	  break;
	}
    }
}


static void
eat_to_eol (bool empty)
{
  bool warned = false;

  while (1)
    {
      int c = input ();

      if (c == EOF)
	break;
      if (c == '\n')
	{
	  ++yylineno;
	  break;
	}

      if (empty && ! isspace (c) && ! warned)
	{
	  error (0, 0, gettext ("%d: garbage at end of line"), yylineno);
	  warned = true;
	}
    }
}


static int
attrib_convert (int c)
{
  if (c == 'X')
    return PF_X;
  if (c == 'W')
    return PF_W;
  assert (c == 'R');
  return PF_R;
}


static void
push_state (enum prepstate state)
{
  if (prepdepth >= MAX_PREPDEPTH)
    error (EXIT_FAILURE, 0, gettext ("%d: conditionals nested too deep"),
	   yylineno);

  prepstate[prepdepth++] = state;
}


static int
pop_state (void)
{
  if (prepdepth == 0)
    error (0, 0, gettext ("%d: unexpected #endif"), yylineno);
  else
    --prepdepth;

  return prepdepth == 0 ? INITIAL : IGNORE;
}


static int
handle_ifdef (void)
{
  char idbuf[50];
  char *id = idbuf;
  size_t idlen = 0;
  size_t idmax = sizeof (idbuf);
  bool ignore_ws = true;
  bool defined = false;
  int result;

  while (1)
    {
      int c = input ();

      if (isspace (c) && ignore_ws)
	continue;

      if (c != '_' && (c < 'a' || c > 'z') && (c < 'A' || c > 'Z')
	  && (idlen == 0 || c < '0' || c > '9'))
	{
	  unput (c);
	  break;
	}

      if (idlen == idmax)
	{
	  char *newp = (char *) alloca (idmax *= 2);
	  id = memcpy (newp, id, idlen);
	}

      id[idlen++] = c;
      ignore_ws = false;
    }

  /* XXX Compare in a better way.  */
  if (idlen == 6 && strncmp (id, "SHARED", 6) == 0)
    defined = ld_state.file_type == dso_file_type;

  if (defined)
    result = INITIAL;
  else
    {
      push_state (skip_if);
      result = IGNORE;
    }

  return result;
}


static void
invalid_char (int ch)
{
  error (0, 0, (isascii (ch)
		? gettext ("invalid character '%c' at line %d; ignored")
		: gettext ("invalid character '\\%o' at line %d; ignored")),
	 ch, yylineno);
}


// Local Variables:
// mode: C
// End: