X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=bfd%2Fcache.c;h=995cf1f9ebac02282ea87ef5c5d2ff1a76ea84c2;hb=7db9a74e9f03427ed2844a17cebecc5e793f38ef;hp=e2524fbf15f06cca89031a6f972266bee5cb3f74;hpb=1b74d0942e058e211902a843647e6487f907e3ec;p=deliverable%2Fbinutils-gdb.git diff --git a/bfd/cache.c b/bfd/cache.c index e2524fbf15..995cf1f9eb 100644 --- a/bfd/cache.c +++ b/bfd/cache.c @@ -1,25 +1,25 @@ /* BFD library -- caching of file descriptors. - Copyright 1990, 1991, 1992, 1993, 1994, 1996, 2000, 2001, 2002, - 2003, 2004 Free Software Foundation, Inc. + Copyright (C) 1990-2016 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 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 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. + 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. */ + 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. */ /* SECTION @@ -30,7 +30,7 @@ SECTION regard to the underlying operating system's file descriptor limit (often as low as 20 open files). The module in <> maintains a least recently used list of - <> files, and exports the name + <> files, and exports the name <>, 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 @@ -40,24 +40,254 @@ SUBSECTION Caching functions */ -#include "bfd.h" #include "sysdep.h" +#include "bfd.h" #include "libbfd.h" #include "libiberty.h" +#include "bfd_stdint.h" + +#ifdef HAVE_MMAP +#include +#endif + +/* In some cases we can optimize cache operation when reopening files. + For instance, a flush is entirely unnecessary if the file is already + closed, so a flush would use CACHE_NO_OPEN. Similarly, a seek using + SEEK_SET or SEEK_END need not first seek to the current position. + For stat we ignore seek errors, just in case the file has changed + while we weren't looking. If it has, then it's possible that the + file is shorter and we don't want a seek error to prevent us doing + the stat. */ +enum cache_flag { + CACHE_NORMAL = 0, + CACHE_NO_OPEN = 1, + CACHE_NO_SEEK = 2, + CACHE_NO_SEEK_ERROR = 4 +}; + +/* The maximum number of files which the cache will keep open at + one time. When needed call bfd_cache_max_open to initialize. */ + +static int max_open_files = 0; + +/* Set max_open_files, if not already set, to 12.5% of the allowed open + file descriptors, but at least 10, and return the value. */ +static int +bfd_cache_max_open (void) +{ + if (max_open_files == 0) + { + int max; +#if defined(__sun) && !defined(__sparcv9) && !defined(__x86_64__) + /* PR ld/19260: 32-bit Solaris has very inelegant handling of the 255 + file descriptor limit. The problem is that setrlimit(2) can raise + RLIMIT_NOFILE to a value that is not supported by libc, resulting + in "Too many open files" errors. This can happen here even though + max_open_files is set to rlim.rlim_cur / 8. For example, if + a parent process has set rlim.rlim_cur to 65536, then max_open_files + will be computed as 8192. + + This check essentially reverts to the behavior from binutils 2.23.1 + for 32-bit Solaris only. (It is hoped that the 32-bit libc + limitation will be removed soon). 64-bit Solaris libc does not have + this limitation. */ + max = 16; +#else +#ifdef HAVE_GETRLIMIT + struct rlimit rlim; + + if (getrlimit (RLIMIT_NOFILE, &rlim) == 0 + && rlim.rlim_cur != (rlim_t) RLIM_INFINITY) + max = rlim.rlim_cur / 8; + else +#endif +#ifdef _SC_OPEN_MAX + max = sysconf (_SC_OPEN_MAX) / 8; +#else + max = 10; +#endif +#endif /* not 32-bit Solaris */ + + max_open_files = max < 10 ? 10 : max; + } + + return max_open_files; +} + +/* The number of BFD files we have open. */ -static bfd_boolean bfd_cache_delete (bfd *); +static int open_files; + +/* Zero, or a pointer to the topmost BFD on the chain. This is + used by the <> macro in @file{libbfd.h} to + determine when it can avoid a function call. */ +static bfd *bfd_last_cache = NULL; + +/* Insert a BFD into the cache. */ + +static void +insert (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 void +snip (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; + } +} + +/* Close a BFD and remove it from the cache. */ + +static bfd_boolean +bfd_cache_delete (bfd *abfd) +{ + bfd_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; +} + +/* We need to open a new file, and the cache is full. Find the least + recently used cacheable BFD and close it. */ + +static bfd_boolean +close_one (void) +{ + register bfd *to_kill; + + if (bfd_last_cache == NULL) + to_kill = NULL; + else + { + for (to_kill = bfd_last_cache->lru_prev; + ! to_kill->cacheable; + to_kill = to_kill->lru_prev) + { + if (to_kill == bfd_last_cache) + { + to_kill = NULL; + break; + } + } + } + + if (to_kill == NULL) + { + /* There are no open cacheable BFD's. */ + return TRUE; + } + + to_kill->where = real_ftell ((FILE *) to_kill->iostream); + + return bfd_cache_delete (to_kill); +} + +/* 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, flag) \ + ((x) == bfd_last_cache \ + ? (FILE *) (bfd_last_cache->iostream) \ + : bfd_cache_lookup_worker (x, flag)) + +/* Called when the macro <> fails to find a + quick answer. Find a file descriptor for @var{abfd}. If + necessary, it open it. If there are already more than + <> files open, it tries to close one first, to + avoid running out of file descriptors. It will return NULL + if it is unable to (re)open the @var{abfd}. */ + +static FILE * +bfd_cache_lookup_worker (bfd *abfd, enum cache_flag flag) +{ + bfd *orig_bfd = abfd; + if ((abfd->flags & BFD_IN_MEMORY) != 0) + abort (); + + while (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); + } + return (FILE *) abfd->iostream; + } + + if (flag & CACHE_NO_OPEN) + return NULL; + + if (bfd_open_file (abfd) == NULL) + ; + else if (!(flag & CACHE_NO_SEEK) + && real_fseek ((FILE *) abfd->iostream, abfd->where, SEEK_SET) != 0 + && !(flag & CACHE_NO_SEEK_ERROR)) + bfd_set_error (bfd_error_system_call); + else + return (FILE *) abfd->iostream; + + (*_bfd_error_handler) (_("reopening %B: %s\n"), + orig_bfd, bfd_errmsg (bfd_get_error ())); + return NULL; +} static file_ptr cache_btell (struct bfd *abfd) { - return real_ftell (bfd_cache_lookup (abfd)); + FILE *f = bfd_cache_lookup (abfd, CACHE_NO_OPEN); + if (f == NULL) + return abfd->where; + return real_ftell (f); } static int cache_bseek (struct bfd *abfd, file_ptr offset, int whence) { - return real_fseek (bfd_cache_lookup (abfd), offset, whence); + FILE *f = bfd_cache_lookup (abfd, whence != SEEK_CUR ? CACHE_NO_SEEK : CACHE_NORMAL); + if (f == NULL) + return -1; + return real_fseek (f, offset, whence); } /* Note that archive entries don't have streams; they share their parent's. @@ -68,8 +298,9 @@ cache_bseek (struct bfd *abfd, file_ptr offset, int whence) first octet in the file, NOT the beginning of the archive header. */ static file_ptr -cache_bread (struct bfd *abfd, void *buf, file_ptr nbytes) +cache_bread_1 (struct bfd *abfd, void *buf, file_ptr nbytes) { + FILE *f; file_ptr nread; /* FIXME - this looks like an optimization, but it's really to cover up for a feature of some OSs (not solaris - sigh) that @@ -83,37 +314,87 @@ cache_bread (struct bfd *abfd, void *buf, file_ptr nbytes) if (nbytes == 0) return 0; + f = bfd_cache_lookup (abfd, CACHE_NORMAL); + if (f == NULL) + return 0; + #if defined (__VAX) && defined (VMS) /* Apparently fread on Vax VMS does not keep the record length information. */ - nread = read (fileno (bfd_cache_lookup (abfd)), buf, nbytes); + nread = read (fileno (f), buf, nbytes); /* Set bfd_error if we did not read as much data as we expected. If the read failed due to an error set the bfd_error_system_call, else set bfd_error_file_truncated. */ if (nread == (file_ptr)-1) { bfd_set_error (bfd_error_system_call); - return -1; + return nread; } #else - nread = fread (buf, 1, nbytes, bfd_cache_lookup (abfd)); + nread = fread (buf, 1, nbytes, f); /* Set bfd_error if we did not read as much data as we expected. If the read failed due to an error set the bfd_error_system_call, else set bfd_error_file_truncated. */ - if (nread < nbytes && ferror (bfd_cache_lookup (abfd))) + if (nread < nbytes && ferror (f)) { bfd_set_error (bfd_error_system_call); - return -1; + return nread; } #endif + if (nread < nbytes) + /* This may or may not be an error, but in case the calling code + bails out because of it, set the right error code. */ + bfd_set_error (bfd_error_file_truncated); + return nread; +} + +static file_ptr +cache_bread (struct bfd *abfd, void *buf, file_ptr nbytes) +{ + file_ptr nread = 0; + + /* Some filesystems are unable to handle reads that are too large + (for instance, NetApp shares with oplocks turned off). To avoid + hitting this limitation, we read the buffer in chunks of 8MB max. */ + while (nread < nbytes) + { + const file_ptr max_chunk_size = 0x800000; + file_ptr chunk_size = nbytes - nread; + file_ptr chunk_nread; + + if (chunk_size > max_chunk_size) + chunk_size = max_chunk_size; + + chunk_nread = cache_bread_1 (abfd, (char *) buf + nread, chunk_size); + + /* Update the nread count. + + We just have to be careful of the case when cache_bread_1 returns + a negative count: If this is our first read, then set nread to + that negative count in order to return that negative value to the + caller. Otherwise, don't add it to our total count, or we would + end up returning a smaller number of bytes read than we actually + did. */ + if (nread == 0 || chunk_nread > 0) + nread += chunk_nread; + + if (chunk_nread < chunk_size) + break; + } + return nread; } static file_ptr cache_bwrite (struct bfd *abfd, const void *where, file_ptr nbytes) { - file_ptr nwrite = fwrite (where, 1, nbytes, bfd_cache_lookup (abfd)); - if (nwrite < nbytes && ferror (bfd_cache_lookup (abfd))) + file_ptr nwrite; + FILE *f = bfd_cache_lookup (abfd, CACHE_NORMAL); + + if (f == NULL) + return 0; + nwrite = fwrite (where, 1, nbytes, f); + if (nwrite < nbytes && ferror (f)) { bfd_set_error (bfd_error_system_call); return -1; @@ -124,13 +405,18 @@ cache_bwrite (struct bfd *abfd, const void *where, file_ptr nbytes) static int cache_bclose (struct bfd *abfd) { - return bfd_cache_close (abfd); + return bfd_cache_close (abfd) - 1; } static int cache_bflush (struct bfd *abfd) { - int sts = fflush (bfd_cache_lookup (abfd)); + int sts; + FILE *f = bfd_cache_lookup (abfd, CACHE_NO_OPEN); + + if (f == NULL) + return 0; + sts = fflush (f); if (sts < 0) bfd_set_error (bfd_error_system_call); return sts; @@ -139,158 +425,75 @@ cache_bflush (struct bfd *abfd) static int cache_bstat (struct bfd *abfd, struct stat *sb) { - int sts = fstat (fileno (bfd_cache_lookup (abfd)), sb); + int sts; + FILE *f = bfd_cache_lookup (abfd, CACHE_NO_SEEK_ERROR); + + if (f == NULL) + return -1; + sts = fstat (fileno (f), sb); if (sts < 0) bfd_set_error (bfd_error_system_call); return sts; } -static const struct bfd_iovec cache_iovec = { - &cache_bread, &cache_bwrite, &cache_btell, &cache_bseek, - &cache_bclose, &cache_bflush, &cache_bstat -}; - -/* -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 <> macro in @file{libbfd.h} to - determine when it can avoid a function call. -*/ - -bfd *bfd_last_cache = NULL; - -/* - 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 void -insert (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 void -snip (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 bfd_boolean -close_one (void) +static void * +cache_bmmap (struct bfd *abfd ATTRIBUTE_UNUSED, + void *addr ATTRIBUTE_UNUSED, + bfd_size_type len ATTRIBUTE_UNUSED, + int prot ATTRIBUTE_UNUSED, + int flags ATTRIBUTE_UNUSED, + file_ptr offset ATTRIBUTE_UNUSED, + void **map_addr ATTRIBUTE_UNUSED, + bfd_size_type *map_len ATTRIBUTE_UNUSED) { - register bfd *kill; + void *ret = (void *) -1; - if (bfd_last_cache == NULL) - kill = NULL; + if ((abfd->flags & BFD_IN_MEMORY) != 0) + abort (); +#ifdef HAVE_MMAP else { - for (kill = bfd_last_cache->lru_prev; - ! kill->cacheable; - kill = kill->lru_prev) - { - if (kill == bfd_last_cache) - { - kill = NULL; - break; - } - } - } + static uintptr_t pagesize_m1; + FILE *f; + file_ptr pg_offset; + bfd_size_type pg_len; - if (kill == NULL) - { - /* There are no open cacheable BFD's. */ - return TRUE; - } + f = bfd_cache_lookup (abfd, CACHE_NO_SEEK_ERROR); + if (f == NULL) + return ret; - kill->where = real_ftell ((FILE *) kill->iostream); + if (pagesize_m1 == 0) + pagesize_m1 = getpagesize () - 1; - return bfd_cache_delete (kill); -} + /* Handle archive members. */ + if (abfd->my_archive != NULL) + offset += abfd->origin; -/* Close a BFD and remove it from the cache. */ + /* Align. */ + pg_offset = offset & ~pagesize_m1; + pg_len = (len + (offset - pg_offset) + pagesize_m1) & ~pagesize_m1; -static bfd_boolean -bfd_cache_delete (bfd *abfd) -{ - bfd_boolean ret; - - if (fclose ((FILE *) abfd->iostream) == 0) - ret = TRUE; - else - { - ret = FALSE; - bfd_set_error (bfd_error_system_call); + ret = mmap (addr, pg_len, prot, flags, fileno (f), pg_offset); + if (ret == (void *) -1) + bfd_set_error (bfd_error_system_call); + else + { + *map_addr = ret; + *map_len = pg_len; + ret = (char *) ret + (offset & pagesize_m1); + } } - - snip (abfd); - - abfd->iostream = NULL; - --open_files; +#endif return ret; } +static const struct bfd_iovec cache_iovec = +{ + &cache_bread, &cache_bwrite, &cache_btell, &cache_bseek, + &cache_bclose, &cache_bflush, &cache_bstat, &cache_bmmap +}; + /* INTERNAL_FUNCTION bfd_cache_init @@ -306,7 +509,7 @@ bfd_boolean bfd_cache_init (bfd *abfd) { BFD_ASSERT (abfd->iostream != NULL); - if (open_files >= BFD_CACHE_MAX_OPEN) + if (open_files >= bfd_cache_max_open ()) { if (! close_one ()) return FALSE; @@ -363,7 +566,7 @@ RETURNS */ bfd_boolean -bfd_cache_close_all () +bfd_cache_close_all (void) { bfd_boolean ret = TRUE; @@ -393,7 +596,7 @@ bfd_open_file (bfd *abfd) { abfd->cacheable = TRUE; /* Allow it to be closed later. */ - if (open_files >= BFD_CACHE_MAX_OPEN) + if (open_files >= bfd_cache_max_open ()) { if (! close_one ()) return NULL; @@ -403,15 +606,15 @@ bfd_open_file (bfd *abfd) { case read_direction: case no_direction: - abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_RB); + abfd->iostream = real_fopen (abfd->filename, FOPEN_RB); break; case both_direction: case write_direction: if (abfd->opened_once) { - abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_RUB); + abfd->iostream = real_fopen (abfd->filename, FOPEN_RUB); if (abfd->iostream == NULL) - abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_WUB); + abfd->iostream = real_fopen (abfd->filename, FOPEN_WUB); } else { @@ -441,13 +644,15 @@ bfd_open_file (bfd *abfd) if (stat (abfd->filename, &s) == 0 && s.st_size != 0) unlink_if_ordinary (abfd->filename); #endif - abfd->iostream = (PTR) fopen (abfd->filename, FOPEN_WUB); + abfd->iostream = real_fopen (abfd->filename, FOPEN_WUB); abfd->opened_once = TRUE; } break; } - if (abfd->iostream != NULL) + if (abfd->iostream == NULL) + bfd_set_error (bfd_error_system_call); + else { if (! bfd_cache_init (abfd)) return NULL; @@ -455,48 +660,3 @@ bfd_open_file (bfd *abfd) return (FILE *) abfd->iostream; } - -/* -INTERNAL_FUNCTION - bfd_cache_lookup_worker - -SYNOPSIS - FILE *bfd_cache_lookup_worker (bfd *abfd); - -DESCRIPTION - Called when the macro <> fails to find a - quick answer. Find a file descriptor for @var{abfd}. If - necessary, it open it. If there are already more than - <> files open, it tries to close one first, to - avoid running out of file descriptors. It will abort rather than - returning NULL if it is unable to (re)open the @var{abfd}. -*/ - -FILE * -bfd_cache_lookup_worker (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 - || abfd->where != (unsigned long) abfd->where - || real_fseek ((FILE *) abfd->iostream, abfd->where, SEEK_SET) != 0) - abort (); - } - - return (FILE *) abfd->iostream; -}