[deliverable/binutils-gdb.git] / bfd / bfdio.c

/* Low-level I/O routines for BFDs.

   Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   1999, 2000, 2001, 2002, 2003, 2004, 2005
   Free Software Foundation, Inc.

   Written by Cygnus Support.

This file is part of BFD, the Binary File Descriptor library.

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 2 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, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */

#include "sysdep.h"

#include "bfd.h"
#include "libbfd.h"

#include <limits.h>

#ifndef S_IXUSR
#define S_IXUSR 0100    /* Execute by owner.  */
#endif
#ifndef S_IXGRP
#define S_IXGRP 0010    /* Execute by group.  */
#endif
#ifndef S_IXOTH
#define S_IXOTH 0001    /* Execute by others.  */
#endif

file_ptr
real_ftell (FILE *file)
{
#if defined (HAVE_FTELLO64)
  return ftello64 (file);
#elif defined (HAVE_FTELLO)
  return ftello (file);
#else
  return ftell (file);
#endif
}

int
real_fseek (FILE *file, file_ptr offset, int whence)
{
#if defined (HAVE_FSEEKO64)
  return fseeko64 (file, offset, whence);
#elif defined (HAVE_FSEEKO)
  return fseeko (file, offset, whence);
#else
  return fseek (file, offset, whence);
#endif
}

FILE *
real_fopen (const char *filename, const char *modes)
{
#if defined (HAVE_FOPEN64)
  return fopen64 (filename, modes);
#else
  return fopen (filename, modes);
#endif
}

/*
INTERNAL_DEFINITION
	struct bfd_iovec

DESCRIPTION

	The <<struct bfd_iovec>> contains the internal file I/O class.
	Each <<BFD>> has an instance of this class and all file I/O is
	routed through it (it is assumed that the instance implements
	all methods listed below).

.struct bfd_iovec
.{
.  {* To avoid problems with macros, a "b" rather than "f"
.     prefix is prepended to each method name.  *}
.  {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching
.     bytes starting at PTR.  Return the number of bytes actually
.     transfered (a read past end-of-file returns less than NBYTES),
.     or -1 (setting <<bfd_error>>) if an error occurs.  *}
.  file_ptr (*bread) (struct bfd *abfd, void *ptr, file_ptr nbytes);
.  file_ptr (*bwrite) (struct bfd *abfd, const void *ptr,
.                      file_ptr nbytes);
.  {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>>
.     if an error occurs.  *}
.  file_ptr (*btell) (struct bfd *abfd);
.  {* For the following, on successful completion a value of 0 is returned.
.     Otherwise, a value of -1 is returned (and  <<bfd_error>> is set).  *}
.  int (*bseek) (struct bfd *abfd, file_ptr offset, int whence);
.  int (*bclose) (struct bfd *abfd);
.  int (*bflush) (struct bfd *abfd);
.  int (*bstat) (struct bfd *abfd, struct stat *sb);
.};

*/


/* Return value is amount read.  */

bfd_size_type
bfd_bread (void *ptr, bfd_size_type size, bfd *abfd)
{
  size_t nread;

  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    {
      struct bfd_in_memory *bim;
      bfd_size_type get;

      bim = abfd->iostream;
      get = size;
      if (abfd->where + get > bim->size)
	{
	  if (bim->size < (bfd_size_type) abfd->where)
	    get = 0;
	  else
	    get = bim->size - abfd->where;
	  bfd_set_error (bfd_error_file_truncated);
	}
      memcpy (ptr, bim->buffer + abfd->where, (size_t) get);
      abfd->where += get;
      return get;
    }

  if (abfd->iovec)
    nread = abfd->iovec->bread (abfd, ptr, size);
  else
    nread = 0;
  if (nread != (size_t) -1)
    abfd->where += nread;

  return nread;
}

bfd_size_type
bfd_bwrite (const void *ptr, bfd_size_type size, bfd *abfd)
{
  size_t nwrote;

  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    {
      struct bfd_in_memory *bim = abfd->iostream;

      size = (size_t) size;
      if (abfd->where + size > bim->size)
	{
	  bfd_size_type newsize, oldsize;

	  oldsize = (bim->size + 127) & ~(bfd_size_type) 127;
	  bim->size = abfd->where + size;
	  /* Round up to cut down on memory fragmentation */
	  newsize = (bim->size + 127) & ~(bfd_size_type) 127;
	  if (newsize > oldsize)
	    {
	      bim->buffer = bfd_realloc (bim->buffer, newsize);
	      if (bim->buffer == 0)
		{
		  bim->size = 0;
		  return 0;
		}
	    }
	}
      memcpy (bim->buffer + abfd->where, ptr, (size_t) size);
      abfd->where += size;
      return size;
    }

  if (abfd->iovec)
    nwrote = abfd->iovec->bwrite (abfd, ptr, size);
  else
    nwrote = 0;

  if (nwrote != (size_t) -1)
    abfd->where += nwrote;
  if (nwrote != size)
    {
#ifdef ENOSPC
      errno = ENOSPC;
#endif
      bfd_set_error (bfd_error_system_call);
    }
  return nwrote;
}

file_ptr
bfd_tell (bfd *abfd)
{
  file_ptr ptr;

  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    return abfd->where;

  if (abfd->iovec)
    {
      ptr = abfd->iovec->btell (abfd);

      if (abfd->my_archive)
	ptr -= abfd->origin;
    }
  else
    ptr = 0;

  abfd->where = ptr;
  return ptr;
}

int
bfd_flush (bfd *abfd)
{
  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    return 0;

  if (abfd->iovec)
    return abfd->iovec->bflush (abfd);
  return 0;
}

/* Returns 0 for success, negative value for failure (in which case
   bfd_get_error can retrieve the error code).  */
int
bfd_stat (bfd *abfd, struct stat *statbuf)
{
  int result;

  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    abort ();

  if (abfd->iovec)
    result = abfd->iovec->bstat (abfd, statbuf);
  else
    result = -1;

  if (result < 0)
    bfd_set_error (bfd_error_system_call);
  return result;
}

/* Returns 0 for success, nonzero for failure (in which case bfd_get_error
   can retrieve the error code).  */

int
bfd_seek (bfd *abfd, file_ptr position, int direction)
{
  int result;
  file_ptr file_position;
  /* For the time being, a BFD may not seek to it's end.  The problem
     is that we don't easily have a way to recognize the end of an
     element in an archive.  */

  BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR);

  if (direction == SEEK_CUR && position == 0)
    return 0;

  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    {
      struct bfd_in_memory *bim;

      bim = abfd->iostream;

      if (direction == SEEK_SET)
	abfd->where = position;
      else
	abfd->where += position;

      if (abfd->where > bim->size)
	{
	  if ((abfd->direction == write_direction) ||
	      (abfd->direction == both_direction))
	    {
	      bfd_size_type newsize, oldsize;

	      oldsize = (bim->size + 127) & ~(bfd_size_type) 127;
	      bim->size = abfd->where;
	      /* Round up to cut down on memory fragmentation */
	      newsize = (bim->size + 127) & ~(bfd_size_type) 127;
	      if (newsize > oldsize)
	        {
		  bim->buffer = bfd_realloc (bim->buffer, newsize);
		  if (bim->buffer == 0)
		    {
		      bim->size = 0;
		      return -1;
		    }
	        }
	    }
	  else
	    {
	      abfd->where = bim->size;
	      bfd_set_error (bfd_error_file_truncated);
	      return -1;
	    }
	}
      return 0;
    }

  if (abfd->format != bfd_archive && abfd->my_archive == 0)
    {
      if (direction == SEEK_SET && (bfd_vma) position == abfd->where)
	return 0;
    }
  else
    {
      /* We need something smarter to optimize access to archives.
	 Currently, anything inside an archive is read via the file
	 handle for the archive.  Which means that a bfd_seek on one
	 component affects the `current position' in the archive, as
	 well as in any other component.

	 It might be sufficient to put a spike through the cache
	 abstraction, and look to the archive for the file position,
	 but I think we should try for something cleaner.

	 In the meantime, no optimization for archives.  */
    }

  file_position = position;
  if (direction == SEEK_SET && abfd->my_archive != NULL)
    file_position += abfd->origin;

  if (abfd->iovec)
    result = abfd->iovec->bseek (abfd, file_position, direction);
  else
    result = -1;

  if (result != 0)
    {
      int hold_errno = errno;

      /* Force redetermination of `where' field.  */
      bfd_tell (abfd);

      /* An EINVAL error probably means that the file offset was
         absurd.  */
      if (hold_errno == EINVAL)
	bfd_set_error (bfd_error_file_truncated);
      else
	{
	  bfd_set_error (bfd_error_system_call);
	  errno = hold_errno;
	}
    }
  else
    {
      /* Adjust `where' field.  */
      if (direction == SEEK_SET)
	abfd->where = position;
      else
	abfd->where += position;
    }
  return result;
}

/*
FUNCTION
	bfd_get_mtime

SYNOPSIS
	long bfd_get_mtime (bfd *abfd);

DESCRIPTION
	Return the file modification time (as read from the file system, or
	from the archive header for archive members).

*/

long
bfd_get_mtime (bfd *abfd)
{
  struct stat buf;

  if (abfd->mtime_set)
    return abfd->mtime;

  if (abfd->iovec == NULL)
    return 0;

  if (abfd->iovec->bstat (abfd, &buf) != 0)
    return 0;

  abfd->mtime = buf.st_mtime;		/* Save value in case anyone wants it */
  return buf.st_mtime;
}

/*
FUNCTION
	bfd_get_size

SYNOPSIS
	long bfd_get_size (bfd *abfd);

DESCRIPTION
	Return the file size (as read from file system) for the file
	associated with BFD @var{abfd}.

	The initial motivation for, and use of, this routine is not
	so we can get the exact size of the object the BFD applies to, since
	that might not be generally possible (archive members for example).
	It would be ideal if someone could eventually modify
	it so that such results were guaranteed.

	Instead, we want to ask questions like "is this NNN byte sized
	object I'm about to try read from file offset YYY reasonable?"
	As as example of where we might do this, some object formats
	use string tables for which the first <<sizeof (long)>> bytes of the
	table contain the size of the table itself, including the size bytes.
	If an application tries to read what it thinks is one of these
	string tables, without some way to validate the size, and for
	some reason the size is wrong (byte swapping error, wrong location
	for the string table, etc.), the only clue is likely to be a read
	error when it tries to read the table, or a "virtual memory
	exhausted" error when it tries to allocate 15 bazillon bytes
	of space for the 15 bazillon byte table it is about to read.
	This function at least allows us to answer the question, "is the
	size reasonable?".
*/

long
bfd_get_size (bfd *abfd)
{
  struct stat buf;

  if ((abfd->flags & BFD_IN_MEMORY) != 0)
    return ((struct bfd_in_memory *) abfd->iostream)->size;

  if (abfd->iovec == NULL)
    return 0;

  if (abfd->iovec->bstat (abfd, &buf) != 0)
    return 0;

  return buf.st_size;
}
Commit	Line	Data
93509525	1	/* Low-level I/O routines for BFDs.
7c192733 AC	2
7c192733 AC	3	Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
9553c638 AM	4	1999, 2000, 2001, 2002, 2003, 2004, 2005
9553c638 AM	5	Free Software Foundation, Inc.
7c192733	6
93509525 KD	7	Written by Cygnus Support.
	8
	9	This file is part of BFD, the Binary File Descriptor library.
	10
	11	This program is free software; you can redistribute it and/or modify
	12	it under the terms of the GNU General Public License as published by
	13	the Free Software Foundation; either version 2 of the License, or
	14	(at your option) any later version.
	15
	16	This program is distributed in the hope that it will be useful,
	17	but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	19	GNU General Public License for more details.
	20
	21	You should have received a copy of the GNU General Public License
	22	along with this program; if not, write to the Free Software
3e110533	23	Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
93509525 KD	24
	25	#include "sysdep.h"
	26
	27	#include "bfd.h"
	28	#include "libbfd.h"
	29
	30	#include <limits.h>
	31
	32	#ifndef S_IXUSR
	33	#define S_IXUSR 0100 /* Execute by owner. */
	34	#endif
	35	#ifndef S_IXGRP
	36	#define S_IXGRP 0010 /* Execute by group. */
	37	#endif
	38	#ifndef S_IXOTH
	39	#define S_IXOTH 0001 /* Execute by others. */
	40	#endif
	41
7c192733 AC	42	file_ptr
	43	real_ftell (FILE *file)
	44	{
	45	#if defined (HAVE_FTELLO64)
	46	return ftello64 (file);
	47	#elif defined (HAVE_FTELLO)
	48	return ftello (file);
	49	#else
	50	return ftell (file);
	51	#endif
	52	}
	53
	54	int
	55	real_fseek (FILE *file, file_ptr offset, int whence)
	56	{
	57	#if defined (HAVE_FSEEKO64)
	58	return fseeko64 (file, offset, whence);
	59	#elif defined (HAVE_FSEEKO)
	60	return fseeko (file, offset, whence);
	61	#else
	62	return fseek (file, offset, whence);
	63	#endif
	64	}
	65
2e6f4fae DJ	66	FILE *
	67	real_fopen (const char filename, const char modes)
	68	{
	69	#if defined (HAVE_FOPEN64)
	70	return fopen64 (filename, modes);
	71	#else
	72	return fopen (filename, modes);
	73	#endif
	74	}
	75
40838a72 AC	76	/*
	77	INTERNAL_DEFINITION
	78	struct bfd_iovec
93509525	79
40838a72	80	DESCRIPTION
93509525	81
40838a72 AC	82	The <<struct bfd_iovec>> contains the internal file I/O class.
	83	Each <<BFD>> has an instance of this class and all file I/O is
	84	routed through it (it is assumed that the instance implements
	85	all methods listed below).
	86
	87	.struct bfd_iovec
	88	.{
	89	. {* To avoid problems with macros, a "b" rather than "f"
	90	. prefix is prepended to each method name. *}
	91	. {* Attempt to read/write NBYTES on ABFD's IOSTREAM storing/fetching
	92	. bytes starting at PTR. Return the number of bytes actually
	93	. transfered (a read past end-of-file returns less than NBYTES),
	94	. or -1 (setting <<bfd_error>>) if an error occurs. *}
	95	. file_ptr (bread) (struct bfd abfd, void *ptr, file_ptr nbytes);
	96	. file_ptr (bwrite) (struct bfd abfd, const void *ptr,
	97	. file_ptr nbytes);
	98	. {* Return the current IOSTREAM file offset, or -1 (setting <<bfd_error>>
	99	. if an error occurs. *}
	100	. file_ptr (btell) (struct bfd abfd);
	101	. {* For the following, on successful completion a value of 0 is returned.
	102	. Otherwise, a value of -1 is returned (and <<bfd_error>> is set). *}
	103	. int (bseek) (struct bfd abfd, file_ptr offset, int whence);
	104	. int (bclose) (struct bfd abfd);
	105	. int (bflush) (struct bfd abfd);
	106	. int (bstat) (struct bfd abfd, struct stat *sb);
	107	.};
93509525	108
40838a72	109	*/
93509525	110
93509525 KD	111
	112	/* Return value is amount read. */
	113
	114	bfd_size_type
c58b9523	115	bfd_bread (void ptr, bfd_size_type size, bfd abfd)
93509525 KD	116	{
	117	size_t nread;
	118
	119	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	120	{
	121	struct bfd_in_memory *bim;
	122	bfd_size_type get;
	123
c58b9523	124	bim = abfd->iostream;
93509525 KD	125	get = size;
	126	if (abfd->where + get > bim->size)
	127	{
	128	if (bim->size < (bfd_size_type) abfd->where)
	129	get = 0;
	130	else
	131	get = bim->size - abfd->where;
	132	bfd_set_error (bfd_error_file_truncated);
	133	}
	134	memcpy (ptr, bim->buffer + abfd->where, (size_t) get);
	135	abfd->where += get;
	136	return get;
	137	}
	138
69fd4758 NC	139	if (abfd->iovec)
	140	nread = abfd->iovec->bread (abfd, ptr, size);
	141	else
	142	nread = 0;
93509525 KD	143	if (nread != (size_t) -1)
	144	abfd->where += nread;
	145
93509525 KD	146	return nread;
	147	}
	148
	149	bfd_size_type
c58b9523	150	bfd_bwrite (const void ptr, bfd_size_type size, bfd abfd)
93509525 KD	151	{
	152	size_t nwrote;
	153
	154	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	155	{
c58b9523	156	struct bfd_in_memory *bim = abfd->iostream;
69fd4758	157
93509525 KD	158	size = (size_t) size;
	159	if (abfd->where + size > bim->size)
	160	{
	161	bfd_size_type newsize, oldsize;
	162
	163	oldsize = (bim->size + 127) & ~(bfd_size_type) 127;
	164	bim->size = abfd->where + size;
	165	/* Round up to cut down on memory fragmentation */
	166	newsize = (bim->size + 127) & ~(bfd_size_type) 127;
	167	if (newsize > oldsize)
	168	{
c58b9523	169	bim->buffer = bfd_realloc (bim->buffer, newsize);
93509525 KD	170	if (bim->buffer == 0)
	171	{
	172	bim->size = 0;
	173	return 0;
	174	}
	175	}
	176	}
	177	memcpy (bim->buffer + abfd->where, ptr, (size_t) size);
	178	abfd->where += size;
	179	return size;
	180	}
	181
69fd4758 NC	182	if (abfd->iovec)
	183	nwrote = abfd->iovec->bwrite (abfd, ptr, size);
	184	else
	185	nwrote = 0;
	186
93509525 KD	187	if (nwrote != (size_t) -1)
	188	abfd->where += nwrote;
	189	if (nwrote != size)
	190	{
	191	#ifdef ENOSPC
	192	errno = ENOSPC;
	193	#endif
	194	bfd_set_error (bfd_error_system_call);
	195	}
	196	return nwrote;
	197	}
	198
7c192733	199	file_ptr
c58b9523	200	bfd_tell (bfd *abfd)
93509525 KD	201	{
	202	file_ptr ptr;
	203
	204	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	205	return abfd->where;
	206
69fd4758 NC	207	if (abfd->iovec)
	208	{
	209	ptr = abfd->iovec->btell (abfd);
	210
	211	if (abfd->my_archive)
	212	ptr -= abfd->origin;
	213	}
	214	else
	215	ptr = 0;
93509525	216
93509525 KD	217	abfd->where = ptr;
	218	return ptr;
	219	}
	220
	221	int
c58b9523	222	bfd_flush (bfd *abfd)
93509525 KD	223	{
	224	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	225	return 0;
69fd4758 NC	226
	227	if (abfd->iovec)
	228	return abfd->iovec->bflush (abfd);
	229	return 0;
93509525 KD	230	}
	231
	232	/* Returns 0 for success, negative value for failure (in which case
	233	bfd_get_error can retrieve the error code). */
	234	int
c58b9523	235	bfd_stat (bfd abfd, struct stat statbuf)
93509525	236	{
93509525 KD	237	int result;
	238
	239	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	240	abort ();
	241
69fd4758 NC	242	if (abfd->iovec)
	243	result = abfd->iovec->bstat (abfd, statbuf);
	244	else
	245	result = -1;
	246
93509525 KD	247	if (result < 0)
	248	bfd_set_error (bfd_error_system_call);
	249	return result;
	250	}
	251
	252	/* Returns 0 for success, nonzero for failure (in which case bfd_get_error
	253	can retrieve the error code). */
	254
	255	int
c58b9523	256	bfd_seek (bfd *abfd, file_ptr position, int direction)
93509525 KD	257	{
93509525 KD	258	int result;
7c192733	259	file_ptr file_position;
93509525 KD	260	/* For the time being, a BFD may not seek to it's end. The problem
	261	is that we don't easily have a way to recognize the end of an
	262	element in an archive. */
	263
	264	BFD_ASSERT (direction == SEEK_SET \|\| direction == SEEK_CUR);
	265
	266	if (direction == SEEK_CUR && position == 0)
	267	return 0;
	268
	269	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	270	{
	271	struct bfd_in_memory *bim;
	272
c58b9523	273	bim = abfd->iostream;
93509525 KD	274
	275	if (direction == SEEK_SET)
	276	abfd->where = position;
	277	else
	278	abfd->where += position;
	279
	280	if (abfd->where > bim->size)
	281	{
	282	if ((abfd->direction == write_direction) \|\|
	283	(abfd->direction == both_direction))
	284	{
	285	bfd_size_type newsize, oldsize;
69fd4758	286
93509525 KD	287	oldsize = (bim->size + 127) & ~(bfd_size_type) 127;
	288	bim->size = abfd->where;
	289	/* Round up to cut down on memory fragmentation */
	290	newsize = (bim->size + 127) & ~(bfd_size_type) 127;
	291	if (newsize > oldsize)
	292	{
c58b9523	293	bim->buffer = bfd_realloc (bim->buffer, newsize);
93509525 KD	294	if (bim->buffer == 0)
	295	{
	296	bim->size = 0;
	297	return -1;
	298	}
	299	}
	300	}
	301	else
	302	{
	303	abfd->where = bim->size;
	304	bfd_set_error (bfd_error_file_truncated);
	305	return -1;
	306	}
	307	}
	308	return 0;
	309	}
	310
	311	if (abfd->format != bfd_archive && abfd->my_archive == 0)
	312	{
93509525 KD	313	if (direction == SEEK_SET && (bfd_vma) position == abfd->where)
	314	return 0;
	315	}
	316	else
	317	{
	318	/* We need something smarter to optimize access to archives.
	319	Currently, anything inside an archive is read via the file
	320	handle for the archive. Which means that a bfd_seek on one
	321	component affects the `current position' in the archive, as
	322	well as in any other component.
	323
	324	It might be sufficient to put a spike through the cache
	325	abstraction, and look to the archive for the file position,
	326	but I think we should try for something cleaner.
	327
	328	In the meantime, no optimization for archives. */
	329	}
	330
93509525 KD	331	file_position = position;
	332	if (direction == SEEK_SET && abfd->my_archive != NULL)
	333	file_position += abfd->origin;
	334
69fd4758 NC	335	if (abfd->iovec)
	336	result = abfd->iovec->bseek (abfd, file_position, direction);
	337	else
	338	result = -1;
	339
93509525 KD	340	if (result != 0)
	341	{
	342	int hold_errno = errno;
	343
	344	/* Force redetermination of `where' field. */
	345	bfd_tell (abfd);
	346
	347	/* An EINVAL error probably means that the file offset was
	348	absurd. */
	349	if (hold_errno == EINVAL)
	350	bfd_set_error (bfd_error_file_truncated);
	351	else
	352	{
	353	bfd_set_error (bfd_error_system_call);
	354	errno = hold_errno;
	355	}
	356	}
	357	else
	358	{
	359	/* Adjust `where' field. */
	360	if (direction == SEEK_SET)
	361	abfd->where = position;
	362	else
	363	abfd->where += position;
	364	}
	365	return result;
	366	}
	367
	368	/*
	369	FUNCTION
	370	bfd_get_mtime
	371
	372	SYNOPSIS
c58b9523	373	long bfd_get_mtime (bfd *abfd);
93509525 KD	374
	375	DESCRIPTION
	376	Return the file modification time (as read from the file system, or
	377	from the archive header for archive members).
	378
	379	*/
	380
	381	long
c58b9523	382	bfd_get_mtime (bfd *abfd)
93509525	383	{
93509525 KD	384	struct stat buf;
	385
	386	if (abfd->mtime_set)
	387	return abfd->mtime;
	388
69fd4758 NC	389	if (abfd->iovec == NULL)
	390	return 0;
	391
40838a72	392	if (abfd->iovec->bstat (abfd, &buf) != 0)
93509525 KD	393	return 0;
	394
	395	abfd->mtime = buf.st_mtime; /* Save value in case anyone wants it */
	396	return buf.st_mtime;
	397	}
	398
	399	/*
	400	FUNCTION
	401	bfd_get_size
	402
	403	SYNOPSIS
c58b9523	404	long bfd_get_size (bfd *abfd);
93509525 KD	405
	406	DESCRIPTION
	407	Return the file size (as read from file system) for the file
	408	associated with BFD @var{abfd}.
	409
	410	The initial motivation for, and use of, this routine is not
	411	so we can get the exact size of the object the BFD applies to, since
	412	that might not be generally possible (archive members for example).
	413	It would be ideal if someone could eventually modify
	414	it so that such results were guaranteed.
	415
	416	Instead, we want to ask questions like "is this NNN byte sized
	417	object I'm about to try read from file offset YYY reasonable?"
	418	As as example of where we might do this, some object formats
	419	use string tables for which the first <<sizeof (long)>> bytes of the
	420	table contain the size of the table itself, including the size bytes.
	421	If an application tries to read what it thinks is one of these
	422	string tables, without some way to validate the size, and for
	423	some reason the size is wrong (byte swapping error, wrong location
	424	for the string table, etc.), the only clue is likely to be a read
	425	error when it tries to read the table, or a "virtual memory
	426	exhausted" error when it tries to allocate 15 bazillon bytes
	427	of space for the 15 bazillon byte table it is about to read.
5c4491d3	428	This function at least allows us to answer the question, "is the
93509525 KD	429	size reasonable?".
	430	*/
	431
	432	long
c58b9523	433	bfd_get_size (bfd *abfd)
93509525	434	{
93509525 KD	435	struct stat buf;
	436
	437	if ((abfd->flags & BFD_IN_MEMORY) != 0)
	438	return ((struct bfd_in_memory *) abfd->iostream)->size;
	439
69fd4758 NC	440	if (abfd->iovec == NULL)
	441	return 0;
	442
40838a72	443	if (abfd->iovec->bstat (abfd, &buf) != 0)
93509525 KD	444	return 0;
	445
	446	return buf.st_size;
	447	}