/* opncls.c -- open and close a BFD. Copyright (C) 1990-2020 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 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, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ #include "sysdep.h" #include "bfd.h" #include "objalloc.h" #include "libbfd.h" #include "libiberty.h" #include "elf-bfd.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 /* Counters used to initialize the bfd identifier. */ static unsigned int bfd_id_counter = 0; static unsigned int bfd_reserved_id_counter = 0; /* CODE_FRAGMENT .{* Set to N to open the next N BFDs using an alternate id space. *} .extern unsigned int bfd_use_reserved_id; */ unsigned int bfd_use_reserved_id = 0; /* fdopen is a loser -- we should use stdio exclusively. Unfortunately if we do that we can't use fcntl. */ /* Return a new BFD. All BFD's are allocated through this routine. */ bfd * _bfd_new_bfd (void) { bfd *nbfd; nbfd = (bfd *) bfd_zmalloc (sizeof (bfd)); if (nbfd == NULL) return NULL; if (bfd_use_reserved_id) { nbfd->id = --bfd_reserved_id_counter; --bfd_use_reserved_id; } else nbfd->id = bfd_id_counter++; nbfd->memory = objalloc_create (); if (nbfd->memory == NULL) { bfd_set_error (bfd_error_no_memory); free (nbfd); return NULL; } nbfd->arch_info = &bfd_default_arch_struct; if (!bfd_hash_table_init_n (& nbfd->section_htab, bfd_section_hash_newfunc, sizeof (struct section_hash_entry), 13)) { objalloc_free ((struct objalloc *) nbfd->memory); free (nbfd); return NULL; } return nbfd; } static const struct bfd_iovec opncls_iovec; /* Allocate a new BFD as a member of archive OBFD. */ bfd * _bfd_new_bfd_contained_in (bfd *obfd) { bfd *nbfd; nbfd = _bfd_new_bfd (); if (nbfd == NULL) return NULL; nbfd->xvec = obfd->xvec; nbfd->iovec = obfd->iovec; if (obfd->iovec == &opncls_iovec) nbfd->iostream = obfd->iostream; nbfd->my_archive = obfd; nbfd->direction = read_direction; nbfd->target_defaulted = obfd->target_defaulted; nbfd->lto_output = obfd->lto_output; nbfd->no_export = obfd->no_export; return nbfd; } /* Delete a BFD. */ static void _bfd_delete_bfd (bfd *abfd) { if (abfd->memory) { bfd_hash_table_free (&abfd->section_htab); objalloc_free ((struct objalloc *) abfd->memory); } else free ((char *) bfd_get_filename (abfd)); free (abfd->arelt_data); free (abfd); } /* Free objalloc memory. */ bfd_boolean _bfd_free_cached_info (bfd *abfd) { if (abfd->memory) { const char *filename = bfd_get_filename (abfd); if (filename) { /* We can't afford to lose the bfd filename when freeing abfd->memory, because that would kill the cache.c scheme of closing and reopening files in order to limit the number of open files. To reopen, you need the filename. And indeed _bfd_compute_and_write_armap calls _bfd_free_cached_info to free up space used by symbols and by check_format_matches. Which we want to continue doing to handle very large archives. Later the archive elements are copied, which might require reopening files. We also want to keep using objalloc memory for the filename since that allows the name to be updated without either leaking memory or implementing some sort of reference counted string for copies of the filename. */ size_t len = strlen (filename) + 1; char *copy = bfd_malloc (len); if (copy == NULL) return FALSE; memcpy (copy, filename, len); abfd->filename = copy; } bfd_hash_table_free (&abfd->section_htab); objalloc_free ((struct objalloc *) abfd->memory); abfd->sections = NULL; abfd->section_last = NULL; abfd->outsymbols = NULL; abfd->tdata.any = NULL; abfd->usrdata = NULL; abfd->memory = NULL; } return TRUE; } /* SECTION Opening and closing BFDs SUBSECTION Functions for opening and closing */ /* FUNCTION bfd_fopen SYNOPSIS bfd *bfd_fopen (const char *filename, const char *target, const char *mode, int fd); DESCRIPTION Open the file @var{filename} with the target @var{target}. Return a pointer to the created BFD. If @var{fd} is not -1, then <> is used to open the file; otherwise, <> is used. @var{mode} is passed directly to <> or <>. Calls <>, so @var{target} is interpreted as by that function. The new BFD is marked as cacheable iff @var{fd} is -1. If <> is returned then an error has occured. Possible errors are <>, <> or <> error. On error, @var{fd} is always closed. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ bfd * bfd_fopen (const char *filename, const char *target, const char *mode, int fd) { bfd *nbfd; const bfd_target *target_vec; nbfd = _bfd_new_bfd (); if (nbfd == NULL) { if (fd != -1) close (fd); return NULL; } target_vec = bfd_find_target (target, nbfd); if (target_vec == NULL) { if (fd != -1) close (fd); _bfd_delete_bfd (nbfd); return NULL; } #ifdef HAVE_FDOPEN if (fd != -1) nbfd->iostream = fdopen (fd, mode); else #endif nbfd->iostream = _bfd_real_fopen (filename, mode); if (nbfd->iostream == NULL) { bfd_set_error (bfd_error_system_call); if (fd != -1) close (fd); _bfd_delete_bfd (nbfd); return NULL; } /* OK, put everything where it belongs. */ /* PR 11983: Do not cache the original filename, but rather make a copy - the original might go away. */ if (!bfd_set_filename (nbfd, filename)) { fclose (nbfd->iostream); _bfd_delete_bfd (nbfd); return NULL; } /* Figure out whether the user is opening the file for reading, writing, or both, by looking at the MODE argument. */ if ((mode[0] == 'r' || mode[0] == 'w' || mode[0] == 'a') && mode[1] == '+') nbfd->direction = both_direction; else if (mode[0] == 'r') nbfd->direction = read_direction; else nbfd->direction = write_direction; if (!bfd_cache_init (nbfd)) { fclose (nbfd->iostream); _bfd_delete_bfd (nbfd); return NULL; } nbfd->opened_once = TRUE; /* If we opened the file by name, mark it cacheable; we can close it and reopen it later. However, if a file descriptor was provided, then it may have been opened with special flags that make it unsafe to close and reopen the file. */ if (fd == -1) (void) bfd_set_cacheable (nbfd, TRUE); return nbfd; } /* FUNCTION bfd_openr SYNOPSIS bfd *bfd_openr (const char *filename, const char *target); DESCRIPTION Open the file @var{filename} (using <>) with the target @var{target}. Return a pointer to the created BFD. Calls <>, so @var{target} is interpreted as by that function. If <> is returned then an error has occured. Possible errors are <>, <> or <> error. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ bfd * bfd_openr (const char *filename, const char *target) { return bfd_fopen (filename, target, FOPEN_RB, -1); } /* Don't try to `optimize' this function: o - We lock using stack space so that interrupting the locking won't cause a storage leak. o - We open the file stream last, since we don't want to have to close it if anything goes wrong. Closing the stream means closing the file descriptor too, even though we didn't open it. */ /* FUNCTION bfd_fdopenr SYNOPSIS bfd *bfd_fdopenr (const char *filename, const char *target, int fd); DESCRIPTION <> is to <> much like <> is to <>. It opens a BFD on a file already described by the @var{fd} supplied. When the file is later <>d, the file descriptor will be closed. If the caller desires that this file descriptor be cached by BFD (opened as needed, closed as needed to free descriptors for other opens), with the supplied @var{fd} used as an initial file descriptor (but subject to closure at any time), call bfd_set_cacheable(bfd, 1) on the returned BFD. The default is to assume no caching; the file descriptor will remain open until <>, and will not be affected by BFD operations on other files. Possible errors are <>, <> and <>. On error, @var{fd} is closed. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ bfd * bfd_fdopenr (const char *filename, const char *target, int fd) { const char *mode; #if defined(HAVE_FCNTL) && defined(F_GETFL) int fdflags; #endif #if ! defined(HAVE_FCNTL) || ! defined(F_GETFL) mode = FOPEN_RUB; /* Assume full access. */ #else fdflags = fcntl (fd, F_GETFL, NULL); if (fdflags == -1) { int save = errno; close (fd); errno = save; bfd_set_error (bfd_error_system_call); return NULL; } /* (O_ACCMODE) parens are to avoid Ultrix header file bug. */ switch (fdflags & (O_ACCMODE)) { case O_RDONLY: mode = FOPEN_RB; break; case O_WRONLY: mode = FOPEN_RUB; break; case O_RDWR: mode = FOPEN_RUB; break; default: abort (); } #endif return bfd_fopen (filename, target, mode, fd); } /* FUNCTION bfd_fdopenw SYNOPSIS bfd *bfd_fdopenw (const char *filename, const char *target, int fd); DESCRIPTION <> is exactly like <> with the exception that the resulting BFD is suitable for output. */ bfd * bfd_fdopenw (const char *filename, const char *target, int fd) { bfd *out = bfd_fdopenr (filename, target, fd); if (out != NULL) { if (!bfd_write_p (out)) { close (fd); _bfd_delete_bfd (out); out = NULL; bfd_set_error (bfd_error_invalid_operation); } else out->direction = write_direction; } return out; } /* FUNCTION bfd_openstreamr SYNOPSIS bfd *bfd_openstreamr (const char * filename, const char * target, void * stream); DESCRIPTION Open a BFD for read access on an existing stdio stream. When the BFD is passed to <>, the stream will be closed. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ bfd * bfd_openstreamr (const char *filename, const char *target, void *streamarg) { FILE *stream = (FILE *) streamarg; bfd *nbfd; const bfd_target *target_vec; nbfd = _bfd_new_bfd (); if (nbfd == NULL) return NULL; target_vec = bfd_find_target (target, nbfd); if (target_vec == NULL) { _bfd_delete_bfd (nbfd); return NULL; } nbfd->iostream = stream; /* PR 11983: Do not cache the original filename, but rather make a copy - the original might go away. */ if (!bfd_set_filename (nbfd, filename)) { _bfd_delete_bfd (nbfd); return NULL; } nbfd->direction = read_direction; if (! bfd_cache_init (nbfd)) { _bfd_delete_bfd (nbfd); return NULL; } return nbfd; } /* FUNCTION bfd_openr_iovec SYNOPSIS bfd *bfd_openr_iovec (const char *filename, const char *target, void *(*open_func) (struct bfd *nbfd, void *open_closure), void *open_closure, file_ptr (*pread_func) (struct bfd *nbfd, void *stream, void *buf, file_ptr nbytes, file_ptr offset), int (*close_func) (struct bfd *nbfd, void *stream), int (*stat_func) (struct bfd *abfd, void *stream, struct stat *sb)); DESCRIPTION Create and return a BFD backed by a read-only @var{stream}. The @var{stream} is created using @var{open_func}, accessed using @var{pread_func} and destroyed using @var{close_func}. Calls <>, so @var{target} is interpreted as by that function. Calls @var{open_func} (which can call <> and <>) to obtain the read-only stream backing the BFD. @var{open_func} either succeeds returning the non-<> @var{stream}, or fails returning <> (setting <>). Calls @var{pread_func} to request @var{nbytes} of data from @var{stream} starting at @var{offset} (e.g., via a call to <>). @var{pread_func} either succeeds returning the number of bytes read (which can be less than @var{nbytes} when end-of-file), or fails returning -1 (setting <>). Calls @var{close_func} when the BFD is later closed using <>. @var{close_func} either succeeds returning 0, or fails returning -1 (setting <>). Calls @var{stat_func} to fill in a stat structure for bfd_stat, bfd_get_size, and bfd_get_mtime calls. @var{stat_func} returns 0 on success, or returns -1 on failure (setting <>). If <> returns <> then an error has occurred. Possible errors are <>, <> and <>. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ struct opncls { void *stream; file_ptr (*pread) (struct bfd *abfd, void *stream, void *buf, file_ptr nbytes, file_ptr offset); int (*close) (struct bfd *abfd, void *stream); int (*stat) (struct bfd *abfd, void *stream, struct stat *sb); file_ptr where; }; static file_ptr opncls_btell (struct bfd *abfd) { struct opncls *vec = (struct opncls *) abfd->iostream; return vec->where; } static int opncls_bseek (struct bfd *abfd, file_ptr offset, int whence) { struct opncls *vec = (struct opncls *) abfd->iostream; switch (whence) { case SEEK_SET: vec->where = offset; break; case SEEK_CUR: vec->where += offset; break; case SEEK_END: return -1; } return 0; } static file_ptr opncls_bread (struct bfd *abfd, void *buf, file_ptr nbytes) { struct opncls *vec = (struct opncls *) abfd->iostream; file_ptr nread = (vec->pread) (abfd, vec->stream, buf, nbytes, vec->where); if (nread < 0) return nread; vec->where += nread; return nread; } static file_ptr opncls_bwrite (struct bfd *abfd ATTRIBUTE_UNUSED, const void *where ATTRIBUTE_UNUSED, file_ptr nbytes ATTRIBUTE_UNUSED) { return -1; } static int opncls_bclose (struct bfd *abfd) { struct opncls *vec = (struct opncls *) abfd->iostream; /* Since the VEC's memory is bound to the bfd deleting the bfd will free it. */ int status = 0; if (vec->close != NULL) status = (vec->close) (abfd, vec->stream); abfd->iostream = NULL; return status; } static int opncls_bflush (struct bfd *abfd ATTRIBUTE_UNUSED) { return 0; } static int opncls_bstat (struct bfd *abfd, struct stat *sb) { struct opncls *vec = (struct opncls *) abfd->iostream; memset (sb, 0, sizeof (*sb)); if (vec->stat == NULL) return 0; return (vec->stat) (abfd, vec->stream, sb); } static void * opncls_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) { return (void *) -1; } static const struct bfd_iovec opncls_iovec = { &opncls_bread, &opncls_bwrite, &opncls_btell, &opncls_bseek, &opncls_bclose, &opncls_bflush, &opncls_bstat, &opncls_bmmap }; bfd * bfd_openr_iovec (const char *filename, const char *target, void *(*open_p) (struct bfd *, void *), void *open_closure, file_ptr (*pread_p) (struct bfd *, void *, void *, file_ptr, file_ptr), int (*close_p) (struct bfd *, void *), int (*stat_p) (struct bfd *, void *, struct stat *)) { bfd *nbfd; const bfd_target *target_vec; struct opncls *vec; void *stream; nbfd = _bfd_new_bfd (); if (nbfd == NULL) return NULL; target_vec = bfd_find_target (target, nbfd); if (target_vec == NULL) { _bfd_delete_bfd (nbfd); return NULL; } /* PR 11983: Do not cache the original filename, but rather make a copy - the original might go away. */ if (!bfd_set_filename (nbfd, filename)) { _bfd_delete_bfd (nbfd); return NULL; } nbfd->direction = read_direction; /* `open_p (...)' would get expanded by an the open(2) syscall macro. */ stream = (*open_p) (nbfd, open_closure); if (stream == NULL) { _bfd_delete_bfd (nbfd); return NULL; } vec = (struct opncls *) bfd_zalloc (nbfd, sizeof (struct opncls)); vec->stream = stream; vec->pread = pread_p; vec->close = close_p; vec->stat = stat_p; nbfd->iovec = &opncls_iovec; nbfd->iostream = vec; return nbfd; } /* bfd_openw -- open for writing. Returns a pointer to a freshly-allocated BFD on success, or NULL. See comment by bfd_fdopenr before you try to modify this function. */ /* FUNCTION bfd_openw SYNOPSIS bfd *bfd_openw (const char *filename, const char *target); DESCRIPTION Create a BFD, associated with file @var{filename}, using the file format @var{target}, and return a pointer to it. Possible errors are <>, <>, <>. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ bfd * bfd_openw (const char *filename, const char *target) { bfd *nbfd; const bfd_target *target_vec; /* nbfd has to point to head of malloc'ed block so that bfd_close may reclaim it correctly. */ nbfd = _bfd_new_bfd (); if (nbfd == NULL) return NULL; target_vec = bfd_find_target (target, nbfd); if (target_vec == NULL) { _bfd_delete_bfd (nbfd); return NULL; } /* PR 11983: Do not cache the original filename, but rather make a copy - the original might go away. */ if (!bfd_set_filename (nbfd, filename)) { _bfd_delete_bfd (nbfd); return NULL; } nbfd->direction = write_direction; if (bfd_open_file (nbfd) == NULL) { /* File not writeable, etc. */ bfd_set_error (bfd_error_system_call); _bfd_delete_bfd (nbfd); return NULL; } return nbfd; } static inline void _maybe_make_executable (bfd * abfd) { /* If the file was open for writing and is now executable, make it so. */ if (abfd->direction == write_direction && (abfd->flags & (EXEC_P | DYNAMIC)) != 0) { struct stat buf; if (stat (bfd_get_filename (abfd), &buf) == 0 /* Do not attempt to change non-regular files. This is here especially for configure scripts and kernel builds which run tests with "ld [...] -o /dev/null". */ && S_ISREG(buf.st_mode)) { unsigned int mask = umask (0); umask (mask); chmod (bfd_get_filename (abfd), (0777 & (buf.st_mode | ((S_IXUSR | S_IXGRP | S_IXOTH) &~ mask)))); } } } /* FUNCTION bfd_close SYNOPSIS bfd_boolean bfd_close (bfd *abfd); DESCRIPTION Close a BFD. If the BFD was open for writing, then pending operations are completed and the file written out and closed. If the created file is executable, then <> is called to mark it as such. All memory attached to the BFD is released. The file descriptor associated with the BFD is closed (even if it was passed in to BFD by <>). RETURNS <> is returned if all is ok, otherwise <>. */ bfd_boolean bfd_close (bfd *abfd) { if (bfd_write_p (abfd)) { if (! BFD_SEND_FMT (abfd, _bfd_write_contents, (abfd))) return FALSE; } return bfd_close_all_done (abfd); } /* FUNCTION bfd_close_all_done SYNOPSIS bfd_boolean bfd_close_all_done (bfd *); DESCRIPTION Close a BFD. Differs from <> since it does not complete any pending operations. This routine would be used if the application had just used BFD for swapping and didn't want to use any of the writing code. If the created file is executable, then <> is called to mark it as such. All memory attached to the BFD is released. RETURNS <> is returned if all is ok, otherwise <>. */ bfd_boolean bfd_close_all_done (bfd *abfd) { bfd_boolean ret; if (! BFD_SEND (abfd, _close_and_cleanup, (abfd))) return FALSE; ret = abfd->iovec->bclose (abfd) == 0; if (ret) _maybe_make_executable (abfd); _bfd_delete_bfd (abfd); return ret; } /* FUNCTION bfd_create SYNOPSIS bfd *bfd_create (const char *filename, bfd *templ); DESCRIPTION Create a new BFD in the manner of <>, but without opening a file. The new BFD takes the target from the target used by @var{templ}. The format is always set to <>. A copy of the @var{filename} argument is stored in the newly created BFD. It can be accessed via the bfd_get_filename() macro. */ bfd * bfd_create (const char *filename, bfd *templ) { bfd *nbfd; nbfd = _bfd_new_bfd (); if (nbfd == NULL) return NULL; /* PR 11983: Do not cache the original filename, but rather make a copy - the original might go away. */ if (!bfd_set_filename (nbfd, filename)) { _bfd_delete_bfd (nbfd); return NULL; } if (templ) nbfd->xvec = templ->xvec; nbfd->direction = no_direction; bfd_set_format (nbfd, bfd_object); return nbfd; } /* FUNCTION bfd_make_writable SYNOPSIS bfd_boolean bfd_make_writable (bfd *abfd); DESCRIPTION Takes a BFD as created by <> and converts it into one like as returned by <>. It does this by converting the BFD to BFD_IN_MEMORY. It's assumed that you will call <> on this bfd later. RETURNS <> is returned if all is ok, otherwise <>. */ bfd_boolean bfd_make_writable (bfd *abfd) { struct bfd_in_memory *bim; if (abfd->direction != no_direction) { bfd_set_error (bfd_error_invalid_operation); return FALSE; } bim = (struct bfd_in_memory *) bfd_malloc (sizeof (struct bfd_in_memory)); if (bim == NULL) return FALSE; /* bfd_error already set. */ abfd->iostream = bim; /* bfd_bwrite will grow these as needed. */ bim->size = 0; bim->buffer = 0; abfd->flags |= BFD_IN_MEMORY; abfd->iovec = &_bfd_memory_iovec; abfd->origin = 0; abfd->direction = write_direction; abfd->where = 0; return TRUE; } /* FUNCTION bfd_make_readable SYNOPSIS bfd_boolean bfd_make_readable (bfd *abfd); DESCRIPTION Takes a BFD as created by <> and <> and converts it into one like as returned by <>. It does this by writing the contents out to the memory buffer, then reversing the direction. RETURNS <> is returned if all is ok, otherwise <>. */ bfd_boolean bfd_make_readable (bfd *abfd) { if (abfd->direction != write_direction || !(abfd->flags & BFD_IN_MEMORY)) { bfd_set_error (bfd_error_invalid_operation); return FALSE; } if (! BFD_SEND_FMT (abfd, _bfd_write_contents, (abfd))) return FALSE; if (! BFD_SEND (abfd, _close_and_cleanup, (abfd))) return FALSE; abfd->arch_info = &bfd_default_arch_struct; abfd->where = 0; abfd->format = bfd_unknown; abfd->my_archive = NULL; abfd->origin = 0; abfd->opened_once = FALSE; abfd->output_has_begun = FALSE; abfd->section_count = 0; abfd->usrdata = NULL; abfd->cacheable = FALSE; abfd->flags |= BFD_IN_MEMORY; abfd->mtime_set = FALSE; abfd->target_defaulted = TRUE; abfd->direction = read_direction; abfd->sections = 0; abfd->symcount = 0; abfd->outsymbols = 0; abfd->tdata.any = 0; bfd_section_list_clear (abfd); bfd_check_format (abfd, bfd_object); return TRUE; } /* FUNCTION bfd_alloc SYNOPSIS void *bfd_alloc (bfd *abfd, bfd_size_type wanted); DESCRIPTION Allocate a block of @var{wanted} bytes of memory attached to <> and return a pointer to it. */ void * bfd_alloc (bfd *abfd, bfd_size_type size) { void *ret; unsigned long ul_size = (unsigned long) size; if (size != ul_size /* Note - although objalloc_alloc takes an unsigned long as its argument, internally the size is treated as a signed long. This can lead to problems where, for example, a request to allocate -1 bytes can result in just 1 byte being allocated, rather than ((unsigned long) -1) bytes. Also memory checkers will often complain about attempts to allocate a negative amount of memory. So to stop these problems we fail if the size is negative. */ || ((signed long) ul_size) < 0) { bfd_set_error (bfd_error_no_memory); return NULL; } ret = objalloc_alloc ((struct objalloc *) abfd->memory, ul_size); if (ret == NULL) bfd_set_error (bfd_error_no_memory); return ret; } /* FUNCTION bfd_zalloc SYNOPSIS void *bfd_zalloc (bfd *abfd, bfd_size_type wanted); DESCRIPTION Allocate a block of @var{wanted} bytes of zeroed memory attached to <> and return a pointer to it. */ void * bfd_zalloc (bfd *abfd, bfd_size_type size) { void *res; res = bfd_alloc (abfd, size); if (res) memset (res, 0, (size_t) size); return res; } /* Free a block allocated for a BFD. Note: Also frees all more recently allocated blocks! */ void bfd_release (bfd *abfd, void *block) { objalloc_free_block ((struct objalloc *) abfd->memory, block); } /* GNU Extension: separate debug-info files The idea here is that a special section called .gnu_debuglink might be embedded in a binary file, which indicates that some *other* file contains the real debugging information. This special section contains a filename and CRC32 checksum, which we read and resolve to another file, if it exists. This facilitates "optional" provision of debugging information, without having to provide two complete copies of every binary object (with and without debug symbols). */ #define GNU_DEBUGLINK ".gnu_debuglink" #define GNU_DEBUGALTLINK ".gnu_debugaltlink" /* FUNCTION bfd_calc_gnu_debuglink_crc32 SYNOPSIS unsigned long bfd_calc_gnu_debuglink_crc32 (unsigned long crc, const unsigned char *buf, bfd_size_type len); DESCRIPTION Computes a CRC value as used in the .gnu_debuglink section. Advances the previously computed @var{crc} value by computing and adding in the crc32 for @var{len} bytes of @var{buf}. RETURNS Return the updated CRC32 value. */ unsigned long bfd_calc_gnu_debuglink_crc32 (unsigned long crc, const unsigned char *buf, bfd_size_type len) { static const unsigned long crc32_table[256] = { 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d }; const unsigned char *end; crc = ~crc & 0xffffffff; for (end = buf + len; buf < end; ++ buf) crc = crc32_table[(crc ^ *buf) & 0xff] ^ (crc >> 8); return ~crc & 0xffffffff; } /* INTERNAL_FUNCTION bfd_get_debug_link_info_1 SYNOPSIS char *bfd_get_debug_link_info_1 (bfd *abfd, void *crc32_out); DESCRIPTION Extracts the filename and CRC32 value for any separate debug information file associated with @var{abfd}. The @var{crc32_out} parameter is an untyped pointer because this routine is used as a @code{get_func_type} function, but it is expected to be an unsigned long pointer. RETURNS The filename of the associated debug information file, or NULL if there is no such file. If the filename was found then the contents of @var{crc32_out} are updated to hold the corresponding CRC32 value for the file. The returned filename is allocated with @code{malloc}; freeing it is the responsibility of the caller. */ static char * bfd_get_debug_link_info_1 (bfd *abfd, void *crc32_out) { asection *sect; unsigned long *crc32 = (unsigned long *) crc32_out; bfd_byte *contents; unsigned int crc_offset; char *name; bfd_size_type size; ufile_ptr file_size; BFD_ASSERT (abfd); BFD_ASSERT (crc32_out); sect = bfd_get_section_by_name (abfd, GNU_DEBUGLINK); if (sect == NULL) return NULL; size = bfd_section_size (sect); file_size = bfd_get_size (abfd); /* PR 22794: Make sure that the section has a reasonable size. */ if (size < 8 || (file_size != 0 && size >= file_size)) return NULL; if (!bfd_malloc_and_get_section (abfd, sect, &contents)) { free (contents); return NULL; } /* CRC value is stored after the filename, aligned up to 4 bytes. */ name = (char *) contents; /* PR 17597: Avoid reading off the end of the buffer. */ crc_offset = strnlen (name, size) + 1; crc_offset = (crc_offset + 3) & ~3; if (crc_offset + 4 > size) return NULL; *crc32 = bfd_get_32 (abfd, contents + crc_offset); return name; } /* FUNCTION bfd_get_debug_link_info SYNOPSIS char *bfd_get_debug_link_info (bfd *abfd, unsigned long *crc32_out); DESCRIPTION Extracts the filename and CRC32 value for any separate debug information file associated with @var{abfd}. RETURNS The filename of the associated debug information file, or NULL if there is no such file. If the filename was found then the contents of @var{crc32_out} are updated to hold the corresponding CRC32 value for the file. The returned filename is allocated with @code{malloc}; freeing it is the responsibility of the caller. */ char * bfd_get_debug_link_info (bfd *abfd, unsigned long *crc32_out) { return bfd_get_debug_link_info_1 (abfd, crc32_out); } /* FUNCTION bfd_get_alt_debug_link_info SYNOPSIS char *bfd_get_alt_debug_link_info (bfd * abfd, bfd_size_type *buildid_len, bfd_byte **buildid_out); DESCRIPTION Fetch the filename and BuildID value for any alternate debuginfo associated with @var{abfd}. Return NULL if no such info found, otherwise return filename and update @var{buildid_len} and @var{buildid_out}. The returned filename and build_id are allocated with @code{malloc}; freeing them is the responsibility of the caller. */ char * bfd_get_alt_debug_link_info (bfd * abfd, bfd_size_type *buildid_len, bfd_byte **buildid_out) { asection *sect; bfd_byte *contents; unsigned int buildid_offset; char *name; bfd_size_type size; ufile_ptr file_size; BFD_ASSERT (abfd); BFD_ASSERT (buildid_len); BFD_ASSERT (buildid_out); sect = bfd_get_section_by_name (abfd, GNU_DEBUGALTLINK); if (sect == NULL) return NULL; size = bfd_section_size (sect); file_size = bfd_get_size (abfd); if (size < 8 || (file_size != 0 && size >= file_size)) return NULL; if (!bfd_malloc_and_get_section (abfd, sect, & contents)) { free (contents); return NULL; } /* BuildID value is stored after the filename. */ name = (char *) contents; buildid_offset = strnlen (name, size) + 1; if (buildid_offset >= bfd_section_size (sect)) return NULL; *buildid_len = size - buildid_offset; *buildid_out = bfd_malloc (*buildid_len); memcpy (*buildid_out, contents + buildid_offset, *buildid_len); return name; } /* INTERNAL_FUNCTION separate_debug_file_exists SYNOPSIS bfd_boolean separate_debug_file_exists (char *name, void *crc32_p); DESCRIPTION Checks to see if @var{name} is a file and if its contents match @var{crc32}, which is a pointer to an @code{unsigned long} containing a CRC32. The @var{crc32_p} parameter is an untyped pointer because this routine is used as a @code{check_func_type} function. */ static bfd_boolean separate_debug_file_exists (const char *name, void *crc32_p) { static unsigned char buffer [8 * 1024]; unsigned long file_crc = 0; FILE *f; bfd_size_type count; unsigned long crc; BFD_ASSERT (name); BFD_ASSERT (crc32_p); crc = *(unsigned long *) crc32_p; f = _bfd_real_fopen (name, FOPEN_RB); if (f == NULL) return FALSE; while ((count = fread (buffer, 1, sizeof (buffer), f)) > 0) file_crc = bfd_calc_gnu_debuglink_crc32 (file_crc, buffer, count); fclose (f); return crc == file_crc; } /* INTERNAL_FUNCTION separate_alt_debug_file_exists SYNOPSIS bfd_boolean separate_alt_debug_file_exists (char *name, void *unused); DESCRIPTION Checks to see if @var{name} is a file. */ static bfd_boolean separate_alt_debug_file_exists (const char *name, void *unused ATTRIBUTE_UNUSED) { FILE *f; BFD_ASSERT (name); f = _bfd_real_fopen (name, FOPEN_RB); if (f == NULL) return FALSE; fclose (f); return TRUE; } /* INTERNAL_FUNCTION find_separate_debug_file SYNOPSIS char *find_separate_debug_file (bfd *abfd, const char *dir, bfd_boolean include_dirs, get_func_type get, check_func_type check, void *data); DESCRIPTION Searches for a debug information file corresponding to @var{abfd}. The name of the separate debug info file is returned by the @var{get} function. This function scans various fixed locations in the filesystem, including the file tree rooted at @var{dir}. If the @var{include_dirs} parameter is true then the directory components of @var{abfd}'s filename will be included in the searched locations. @var{data} is passed unmodified to the @var{get} and @var{check} functions. It is generally used to implement build-id-like matching in the callback functions. RETURNS Returns the filename of the first file to be found which receives a TRUE result from the @var{check} function. Returns NULL if no valid file could be found. */ typedef char * (* get_func_type) (bfd *, void *); typedef bfd_boolean (* check_func_type) (const char *, void *); static char * find_separate_debug_file (bfd * abfd, const char * debug_file_directory, bfd_boolean include_dirs, get_func_type get_func, check_func_type check_func, void * func_data) { char *base; char *dir; char *debugfile; char *canon_dir; size_t dirlen; size_t canon_dirlen; BFD_ASSERT (abfd); if (debug_file_directory == NULL) debug_file_directory = "."; /* BFD may have been opened from a stream. */ if (bfd_get_filename (abfd) == NULL) { bfd_set_error (bfd_error_invalid_operation); return NULL; } base = get_func (abfd, func_data); if (base == NULL) return NULL; if (base[0] == '\0') { free (base); bfd_set_error (bfd_error_no_debug_section); return NULL; } if (include_dirs) { const char *fname = bfd_get_filename (abfd); for (dirlen = strlen (fname); dirlen > 0; dirlen--) if (IS_DIR_SEPARATOR (fname[dirlen - 1])) break; dir = (char *) bfd_malloc (dirlen + 1); if (dir == NULL) { free (base); return NULL; } memcpy (dir, fname, dirlen); dir[dirlen] = '\0'; } else { dir = (char *) bfd_malloc (1); * dir = 0; dirlen = 0; } /* Compute the canonical name of the bfd object with all symbolic links resolved, for use in the global debugfile directory. */ canon_dir = lrealpath (bfd_get_filename (abfd)); for (canon_dirlen = strlen (canon_dir); canon_dirlen > 0; canon_dirlen--) if (IS_DIR_SEPARATOR (canon_dir[canon_dirlen - 1])) break; canon_dir[canon_dirlen] = '\0'; #ifndef EXTRA_DEBUG_ROOT1 #define EXTRA_DEBUG_ROOT1 "/usr/lib/debug" #endif #ifndef EXTRA_DEBUG_ROOT2 #define EXTRA_DEBUG_ROOT2 "/usr/lib/debug/usr" #endif debugfile = (char *) bfd_malloc (strlen (debug_file_directory) + 1 + (canon_dirlen > dirlen ? canon_dirlen : dirlen) + strlen (".debug/") #ifdef EXTRA_DEBUG_ROOT1 + strlen (EXTRA_DEBUG_ROOT1) #endif #ifdef EXTRA_DEBUG_ROOT2 + strlen (EXTRA_DEBUG_ROOT2) #endif + strlen (base) + 1); if (debugfile == NULL) goto found; /* Actually this returns NULL. */ /* First try in the same directory as the original file. FIXME: Strictly speaking if we are using the build-id method, (ie include_dirs == FALSE) then we should only check absolute paths, not relative ones like this one (and the next one). The check is left in however as this allows the binutils testsuite to exercise this feature without having to install a file into the root filesystem. (See binutils/testsuite/ binutils-all/objdump.exp for the test). */ sprintf (debugfile, "%s%s", dir, base); if (check_func (debugfile, func_data)) goto found; /* Then try in a subdirectory called .debug. */ sprintf (debugfile, "%s.debug/%s", dir, base); if (check_func (debugfile, func_data)) goto found; #ifdef EXTRA_DEBUG_ROOT1 /* Try the first extra debug file root. */ sprintf (debugfile, "%s%s%s", EXTRA_DEBUG_ROOT1, include_dirs ? canon_dir : "/", base); if (check_func (debugfile, func_data)) goto found; #endif #ifdef EXTRA_DEBUG_ROOT2 /* Try the second extra debug file root. */ sprintf (debugfile, "%s%s%s", EXTRA_DEBUG_ROOT2, include_dirs ? canon_dir : "/", base); if (check_func (debugfile, func_data)) goto found; #endif /* Then try in the global debugfile directory. */ strcpy (debugfile, debug_file_directory); dirlen = strlen (debug_file_directory) - 1; if (include_dirs) { if (dirlen > 0 && debug_file_directory[dirlen] != '/' && canon_dir[0] != '/') strcat (debugfile, "/"); strcat (debugfile, canon_dir); } else { if (dirlen > 0 && debug_file_directory[dirlen] != '/') strcat (debugfile, "/"); } strcat (debugfile, base); if (check_func (debugfile, func_data)) goto found; /* Failed to find the file. */ free (debugfile); debugfile = NULL; found: free (base); free (dir); free (canon_dir); return debugfile; } /* FUNCTION bfd_follow_gnu_debuglink SYNOPSIS char *bfd_follow_gnu_debuglink (bfd *abfd, const char *dir); DESCRIPTION Takes a BFD and searches it for a .gnu_debuglink section. If this section is found, it examines the section for the name and checksum of a '.debug' file containing auxiliary debugging information. It then searches the filesystem for this .debug file in some standard locations, including the directory tree rooted at @var{dir}, and if found returns the full filename. If @var{dir} is NULL, the search will take place starting at the current directory. RETURNS <> on any errors or failure to locate the .debug file, otherwise a pointer to a heap-allocated string containing the filename. The caller is responsible for freeing this string. */ char * bfd_follow_gnu_debuglink (bfd *abfd, const char *dir) { unsigned long crc32; return find_separate_debug_file (abfd, dir, TRUE, bfd_get_debug_link_info_1, separate_debug_file_exists, &crc32); } /* Helper for bfd_follow_gnu_debugaltlink. It just returns the name of the separate debug file. */ static char * get_alt_debug_link_info_shim (bfd * abfd, void *unused ATTRIBUTE_UNUSED) { bfd_size_type len; bfd_byte *buildid = NULL; char *result = bfd_get_alt_debug_link_info (abfd, &len, &buildid); free (buildid); return result; } /* FUNCTION bfd_follow_gnu_debugaltlink SYNOPSIS char *bfd_follow_gnu_debugaltlink (bfd *abfd, const char *dir); DESCRIPTION Takes a BFD and searches it for a .gnu_debugaltlink section. If this section is found, it examines the section for the name of a file containing auxiliary debugging information. It then searches the filesystem for this file in a set of standard locations, including the directory tree rooted at @var{dir}, and if found returns the full filename. If @var{dir} is NULL, the search will take place starting at the current directory. RETURNS <> on any errors or failure to locate the debug file, otherwise a pointer to a heap-allocated string containing the filename. The caller is responsible for freeing this string. */ char * bfd_follow_gnu_debugaltlink (bfd *abfd, const char *dir) { return find_separate_debug_file (abfd, dir, TRUE, get_alt_debug_link_info_shim, separate_alt_debug_file_exists, NULL); } /* FUNCTION bfd_create_gnu_debuglink_section SYNOPSIS struct bfd_section *bfd_create_gnu_debuglink_section (bfd *abfd, const char *filename); DESCRIPTION Takes a @var{BFD} and adds a .gnu_debuglink section to it. The section is sized to be big enough to contain a link to the specified @var{filename}. RETURNS A pointer to the new section is returned if all is ok. Otherwise <> is returned and bfd_error is set. */ asection * bfd_create_gnu_debuglink_section (bfd *abfd, const char *filename) { asection *sect; bfd_size_type debuglink_size; flagword flags; if (abfd == NULL || filename == NULL) { bfd_set_error (bfd_error_invalid_operation); return NULL; } /* Strip off any path components in filename. */ filename = lbasename (filename); sect = bfd_get_section_by_name (abfd, GNU_DEBUGLINK); if (sect) { /* Section already exists. */ bfd_set_error (bfd_error_invalid_operation); return NULL; } flags = SEC_HAS_CONTENTS | SEC_READONLY | SEC_DEBUGGING; sect = bfd_make_section_with_flags (abfd, GNU_DEBUGLINK, flags); if (sect == NULL) return NULL; /* Compute the size of the section. Allow for the CRC after the filename, and padding so that it will start on a 4-byte boundary. */ debuglink_size = strlen (filename) + 1; debuglink_size += 3; debuglink_size &= ~3; debuglink_size += 4; if (!bfd_set_section_size (sect, debuglink_size)) /* XXX Should we delete the section from the bfd ? */ return NULL; /* PR 21193: Ensure that the section has 4-byte alignment for the CRC. Note - despite the name of the function being called, we are setting an alignment power, not a byte alignment value. */ bfd_set_section_alignment (sect, 2); return sect; } /* FUNCTION bfd_fill_in_gnu_debuglink_section SYNOPSIS bfd_boolean bfd_fill_in_gnu_debuglink_section (bfd *abfd, struct bfd_section *sect, const char *filename); DESCRIPTION Takes a @var{BFD} and containing a .gnu_debuglink section @var{SECT} and fills in the contents of the section to contain a link to the specified @var{filename}. The filename should be relative to the current directory. RETURNS <> is returned if all is ok. Otherwise <> is returned and bfd_error is set. */ bfd_boolean bfd_fill_in_gnu_debuglink_section (bfd *abfd, struct bfd_section *sect, const char *filename) { bfd_size_type debuglink_size; unsigned long crc32; char * contents; bfd_size_type crc_offset; FILE * handle; static unsigned char buffer[8 * 1024]; size_t count; size_t filelen; if (abfd == NULL || sect == NULL || filename == NULL) { bfd_set_error (bfd_error_invalid_operation); return FALSE; } /* Make sure that we can read the file. XXX - Should we attempt to locate the debug info file using the same algorithm as gdb ? At the moment, since we are creating the .gnu_debuglink section, we insist upon the user providing us with a correct-for-section-creation-time path, but this need not conform to the gdb location algorithm. */ handle = _bfd_real_fopen (filename, FOPEN_RB); if (handle == NULL) { bfd_set_error (bfd_error_system_call); return FALSE; } crc32 = 0; while ((count = fread (buffer, 1, sizeof buffer, handle)) > 0) crc32 = bfd_calc_gnu_debuglink_crc32 (crc32, buffer, count); fclose (handle); /* Strip off any path components in filename, now that we no longer need them. */ filename = lbasename (filename); filelen = strlen (filename); debuglink_size = filelen + 1; debuglink_size += 3; debuglink_size &= ~3; debuglink_size += 4; contents = (char *) bfd_malloc (debuglink_size); if (contents == NULL) { /* XXX Should we delete the section from the bfd ? */ return FALSE; } crc_offset = debuglink_size - 4; memcpy (contents, filename, filelen); memset (contents + filelen, 0, crc_offset - filelen); bfd_put_32 (abfd, crc32, contents + crc_offset); if (! bfd_set_section_contents (abfd, sect, contents, 0, debuglink_size)) { /* XXX Should we delete the section from the bfd ? */ free (contents); return FALSE; } return TRUE; } /* INTERNAL_FUNCTION get_build_id SYNOPSIS struct bfd_build_id * get_build_id (bfd *abfd); DESCRIPTION Finds the build-id associated with @var{abfd}. If the build-id is extracted from the note section then a build-id structure is built for it, using memory allocated to @var{abfd}, and this is then attached to the @var{abfd}. RETURNS Returns a pointer to the build-id structure if a build-id could be found. If no build-id is found NULL is returned and error code is set. */ static struct bfd_build_id * get_build_id (bfd *abfd) { struct bfd_build_id *build_id; Elf_Internal_Note inote; Elf_External_Note *enote; bfd_byte *contents; asection *sect; bfd_size_type size; BFD_ASSERT (abfd); if (abfd->build_id && abfd->build_id->size > 0) /* Save some time by using the already computed build-id. */ return (struct bfd_build_id *) abfd->build_id; sect = bfd_get_section_by_name (abfd, ".note.gnu.build-id"); if (sect == NULL) { bfd_set_error (bfd_error_no_debug_section); return NULL; } size = bfd_section_size (sect); /* FIXME: Should we support smaller build-id notes ? */ if (size < 0x24) { bfd_set_error (bfd_error_invalid_operation); return NULL; } if (!bfd_malloc_and_get_section (abfd, sect, & contents)) { free (contents); return NULL; } /* FIXME: Paranoia - allow for compressed build-id sections. Maybe we should complain if this size is different from the one obtained above... */ size = bfd_section_size (sect); if (size < sizeof (Elf_External_Note)) { bfd_set_error (bfd_error_invalid_operation); free (contents); return NULL; } enote = (Elf_External_Note *) contents; inote.type = H_GET_32 (abfd, enote->type); inote.namesz = H_GET_32 (abfd, enote->namesz); inote.namedata = enote->name; inote.descsz = H_GET_32 (abfd, enote->descsz); inote.descdata = inote.namedata + BFD_ALIGN (inote.namesz, 4); /* FIXME: Should we check for extra notes in this section ? */ if (inote.descsz <= 0 || inote.type != NT_GNU_BUILD_ID || inote.namesz != 4 /* sizeof "GNU" */ || strncmp (inote.namedata, "GNU", 4) != 0 || inote.descsz > 0x7ffffffe || size < (12 + BFD_ALIGN (inote.namesz, 4) + inote.descsz)) { free (contents); bfd_set_error (bfd_error_invalid_operation); return NULL; } build_id = bfd_alloc (abfd, sizeof (struct bfd_build_id) + inote.descsz); if (build_id == NULL) { free (contents); return NULL; } build_id->size = inote.descsz; memcpy (build_id->data, inote.descdata, inote.descsz); abfd->build_id = build_id; free (contents); return build_id; } /* INTERNAL_FUNCTION get_build_id_name SYNOPSIS char * get_build_id_name (bfd *abfd, void *build_id_out_p) DESCRIPTION Searches @var{abfd} for a build-id, and then constructs a pathname from it. The path is computed as .build-id/NN/NN+NN.debug where NNNN+NN is the build-id value as a hexadecimal string. RETURNS Returns the constructed filename or NULL upon error. It is the caller's responsibility to free the memory used to hold the filename. If a filename is returned then the @var{build_id_out_p} parameter (which points to a @code{struct bfd_build_id} pointer) is set to a pointer to the build_id structure. */ static char * get_build_id_name (bfd *abfd, void *build_id_out_p) { struct bfd_build_id **build_id_out = build_id_out_p; struct bfd_build_id *build_id; char *name; char *n; bfd_size_type s; bfd_byte *d; if (abfd == NULL || bfd_get_filename (abfd) == NULL || build_id_out == NULL) { bfd_set_error (bfd_error_invalid_operation); return NULL; } build_id = get_build_id (abfd); if (build_id == NULL) return NULL; /* Compute the debug pathname corresponding to the build-id. */ name = bfd_malloc (strlen (".build-id/") + build_id->size * 2 + 2 + strlen (".debug")); if (name == NULL) { bfd_set_error (bfd_error_no_memory); return NULL; } n = name; d = build_id->data; s = build_id->size; n += sprintf (n, ".build-id/"); n += sprintf (n, "%02x", (unsigned) *d++); s--; n += sprintf (n, "/"); while (s--) n += sprintf (n, "%02x", (unsigned) *d++); n += sprintf (n, ".debug"); *build_id_out = build_id; return name; } /* INTERNAL_FUNCTION check_build_id_file SYNOPSIS bfd_boolean check_build_id_file (char *name, void *buildid_p); DESCRIPTION Checks to see if @var{name} is a readable file and if its build-id matches @var{buildid}. RETURNS Returns TRUE if the file exists, is readable, and contains a build-id which matches the build-id pointed at by @var{build_id_p} (which is really a @code{struct bfd_build_id **}). */ static bfd_boolean check_build_id_file (const char *name, void *buildid_p) { struct bfd_build_id *orig_build_id; struct bfd_build_id *build_id; bfd * file; bfd_boolean result; BFD_ASSERT (name); BFD_ASSERT (buildid_p); file = bfd_openr (name, NULL); if (file == NULL) return FALSE; /* If the file is an archive, process all of its elements. */ if (! bfd_check_format (file, bfd_object)) { bfd_close (file); return FALSE; } build_id = get_build_id (file); if (build_id == NULL) { bfd_close (file); return FALSE; } orig_build_id = *(struct bfd_build_id **) buildid_p; result = build_id->size == orig_build_id->size && memcmp (build_id->data, orig_build_id->data, build_id->size) == 0; (void) bfd_close (file); return result; } /* FUNCTION bfd_follow_build_id_debuglink SYNOPSIS char *bfd_follow_build_id_debuglink (bfd *abfd, const char *dir); DESCRIPTION Takes @var{abfd} and searches it for a .note.gnu.build-id section. If this section is found, it extracts the value of the NT_GNU_BUILD_ID note, which should be a hexadecimal value @var{NNNN+NN} (for 32+ hex digits). It then searches the filesystem for a file named @var{.build-id/NN/NN+NN.debug} in a set of standard locations, including the directory tree rooted at @var{dir}. The filename of the first matching file to be found is returned. A matching file should contain a .note.gnu.build-id section with the same @var{NNNN+NN} note as @var{abfd}, although this check is currently not implemented. If @var{dir} is NULL, the search will take place starting at the current directory. RETURNS <> on any errors or failure to locate the debug file, otherwise a pointer to a heap-allocated string containing the filename. The caller is responsible for freeing this string. */ char * bfd_follow_build_id_debuglink (bfd *abfd, const char *dir) { struct bfd_build_id *build_id; return find_separate_debug_file (abfd, dir, FALSE, get_build_id_name, check_build_id_file, &build_id); } /* FUNCTION bfd_set_filename SYNOPSIS const char *bfd_set_filename (bfd *abfd, const char *filename); DESCRIPTION Set the filename of @var{abfd}, copying the FILENAME parameter to bfd_alloc'd memory owned by @var{abfd}. Returns a pointer the newly allocated name, or NULL if the allocation failed. */ const char * bfd_set_filename (bfd *abfd, const char *filename) { size_t len = strlen (filename) + 1; char *n = bfd_alloc (abfd, len); if (n) { memcpy (n, filename, len); abfd->filename = n; } return n; }