diff options
Diffstat (limited to 'contrib/binutils/bfd/cache.c')
| -rw-r--r-- | contrib/binutils/bfd/cache.c | 350 | 
1 files changed, 0 insertions, 350 deletions
diff --git a/contrib/binutils/bfd/cache.c b/contrib/binutils/bfd/cache.c deleted file mode 100644 index b28de4bc4b96..000000000000 --- a/contrib/binutils/bfd/cache.c +++ /dev/null @@ -1,350 +0,0 @@ -/* BFD library -- caching of file descriptors. -   Copyright 1990, 91, 92, 93, 94, 95, 1996 Free Software Foundation, Inc. -   Hacked by Steve Chamberlain of Cygnus Support (steve@cygnus.com). - -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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */ - -/* -SECTION -	File caching - -	The file caching mechanism is embedded within BFD and allows -	the application to open as many BFDs as it wants without -	regard to the underlying operating system's file descriptor -	limit (often as low as 20 open files).  The module in -	<<cache.c>> maintains a least recently used list of -	<<BFD_CACHE_MAX_OPEN>> files, and exports the name -	<<bfd_cache_lookup>>, which runs around and makes sure that -	the required BFD is open. If not, then it chooses a file to -	close, closes it and opens the one wanted, returning its file -	handle.  - -*/ - -#include "bfd.h" -#include "sysdep.h" -#include "libbfd.h" - -static void insert PARAMS ((bfd *)); -static void snip PARAMS ((bfd *)); -static boolean close_one PARAMS ((void)); -static boolean bfd_cache_delete PARAMS ((bfd *)); - -/* -INTERNAL_FUNCTION -	BFD_CACHE_MAX_OPEN macro - -DESCRIPTION -	The maximum number of files which the cache will keep open at -	one time. - -.#define BFD_CACHE_MAX_OPEN 10 - -*/ - -/* The number of BFD files we have open.  */ - -static int open_files; - -/* -INTERNAL_FUNCTION -	bfd_last_cache - -SYNOPSIS -	extern bfd *bfd_last_cache; - -DESCRIPTION -	Zero, or a pointer to the topmost BFD on the chain.  This is -	used by the <<bfd_cache_lookup>> macro in @file{libbfd.h} to -	determine when it can avoid a function call. -*/ - -bfd *bfd_last_cache; - -/* -  INTERNAL_FUNCTION -  	bfd_cache_lookup -  -  DESCRIPTION - 	Check to see if the required BFD is the same as the last one - 	looked up. If so, then it can use the stream in the BFD with - 	impunity, since it can't have changed since the last lookup; - 	otherwise, it has to perform the complicated lookup function. -  -  .#define bfd_cache_lookup(x) \ -  .    ((x)==bfd_last_cache? \ -  .      (FILE*)(bfd_last_cache->iostream): \ -  .       bfd_cache_lookup_worker(x)) -  -  - */ - -/* Insert a BFD into the cache.  */ - -static INLINE void -insert (abfd) -     bfd *abfd; -{ -  if (bfd_last_cache == NULL) -    { -      abfd->lru_next = abfd; -      abfd->lru_prev = abfd; -    } -  else -    { -      abfd->lru_next = bfd_last_cache; -      abfd->lru_prev = bfd_last_cache->lru_prev; -      abfd->lru_prev->lru_next = abfd; -      abfd->lru_next->lru_prev = abfd; -    } -  bfd_last_cache = abfd; -} - -/* Remove a BFD from the cache.  */ - -static INLINE void -snip (abfd) -     bfd *abfd; -{ -  abfd->lru_prev->lru_next = abfd->lru_next; -  abfd->lru_next->lru_prev = abfd->lru_prev; -  if (abfd == bfd_last_cache) -    { -      bfd_last_cache = abfd->lru_next; -      if (abfd == bfd_last_cache) -	bfd_last_cache = NULL; -    } -} - -/* We need to open a new file, and the cache is full.  Find the least -   recently used cacheable BFD and close it.  */ - -static boolean -close_one () -{ -  register bfd *kill; - -  if (bfd_last_cache == NULL) -    kill = NULL; -  else -    { -      for (kill = bfd_last_cache->lru_prev; -	   ! kill->cacheable; -	   kill = kill->lru_prev) -	{ -	  if (kill == bfd_last_cache) -	    { -	      kill = NULL; -	      break; -	    } -	} -    } - -  if (kill == NULL) -    { -      /* There are no open cacheable BFD's.  */ -      return true; -    } - -  kill->where = ftell ((FILE *) kill->iostream); - -  return bfd_cache_delete (kill); -} - -/* Close a BFD and remove it from the cache.  */ - -static boolean -bfd_cache_delete (abfd) -     bfd *abfd; -{ -  boolean ret; - -  if (fclose ((FILE *) abfd->iostream) == 0) -    ret = true; -  else -    { -      ret = false; -      bfd_set_error (bfd_error_system_call); -    } - -  snip (abfd); - -  abfd->iostream = NULL; -  --open_files; - -  return ret; -} - -/* -INTERNAL_FUNCTION -	bfd_cache_init - -SYNOPSIS -	boolean bfd_cache_init (bfd *abfd); - -DESCRIPTION -	Add a newly opened BFD to the cache. -*/ - -boolean -bfd_cache_init (abfd) -     bfd *abfd; -{ -  BFD_ASSERT (abfd->iostream != NULL); -  if (open_files >= BFD_CACHE_MAX_OPEN) -    { -      if (! close_one ()) -	return false; -    } -  insert (abfd); -  ++open_files; -  return true; -} - -/* -INTERNAL_FUNCTION -	bfd_cache_close - -SYNOPSIS -	boolean bfd_cache_close (bfd *abfd); - -DESCRIPTION -	Remove the BFD @var{abfd} from the cache. If the attached file is open, -	then close it too. - -RETURNS -	<<false>> is returned if closing the file fails, <<true>> is -	returned if all is well. -*/ - -boolean -bfd_cache_close (abfd) -     bfd *abfd; -{ -  if (abfd->iostream == NULL -      || (abfd->flags & BFD_IN_MEMORY) != 0) -    return true; - -  return bfd_cache_delete (abfd); -} - -/* -INTERNAL_FUNCTION -	bfd_open_file - -SYNOPSIS -	FILE* bfd_open_file(bfd *abfd); - -DESCRIPTION -	Call the OS to open a file for @var{abfd}.  Return the <<FILE *>> -	(possibly <<NULL>>) that results from this operation.  Set up the -	BFD so that future accesses know the file is open. If the <<FILE *>> -	returned is <<NULL>>, then it won't have been put in the -	cache, so it won't have to be removed from it. -*/ - -FILE * -bfd_open_file (abfd) -     bfd *abfd; -{ -  abfd->cacheable = true;	/* Allow it to be closed later. */ - -  if (open_files >= BFD_CACHE_MAX_OPEN) -    { -      if (! close_one ()) -	return NULL; -    } - -  switch (abfd->direction) -    { -    case read_direction: -    case no_direction: -      abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_RB); -      break; -    case both_direction: -    case write_direction: -      if (abfd->opened_once == true) -	{ -	  abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_RUB); -	  if (abfd->iostream == NULL) -	    abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_WUB); -	} -      else -	{ -	  /* Create the file.  Unlink it first, for the convenience of -             operating systems which worry about overwriting running -             binaries.  */ -	  unlink (abfd->filename); -	  abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_WB); -	  abfd->opened_once = true; -	} -      break; -    } - -  if (abfd->iostream != NULL) -    { -      if (! bfd_cache_init (abfd)) -	return NULL; -    } - -  return (FILE *) abfd->iostream; -} - -/* -INTERNAL_FUNCTION -	bfd_cache_lookup_worker - -SYNOPSIS -	FILE *bfd_cache_lookup_worker(bfd *abfd); - -DESCRIPTION -	Called when the macro <<bfd_cache_lookup>> fails to find a -	quick answer.  Find a file descriptor for @var{abfd}.  If -	necessary, it open it.  If there are already more than -	<<BFD_CACHE_MAX_OPEN>> files open, it tries to close one first, to -	avoid running out of file descriptors.   -*/ - -FILE * -bfd_cache_lookup_worker (abfd) -     bfd *abfd; -{ -  if ((abfd->flags & BFD_IN_MEMORY) != 0) -    abort (); - -  if (abfd->my_archive)  -    abfd = abfd->my_archive; - -  if (abfd->iostream != NULL) -    { -      /* Move the file to the start of the cache.  */ -      if (abfd != bfd_last_cache) -	{ -	  snip (abfd); -	  insert (abfd); -	} -    } -  else -    { -      if (bfd_open_file (abfd) == NULL) -	return NULL; -      if (fseek ((FILE *) abfd->iostream, abfd->where, SEEK_SET) != 0) -	return NULL; -    } - -  return (FILE *) abfd->iostream; -}  | 
