binutils-gdb/gdb/build-id.h

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fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
/* build-id-related functions.
Copyright (C) 1991-2018 Free Software Foundation, Inc.
fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
This file is part of GDB.
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, see <http://www.gnu.org/licenses/>. */
#ifndef BUILD_ID_H
#define BUILD_ID_H
Use class to manage BFD reference counts This introduces a new specialization of gdb::ref_ptr that can be used to manage BFD reference counts. Then it changes most places in gdb to use this new class, rather than explicit reference-counting or cleanups. This patch removes make_cleanup_bfd_unref. If you look you will see a couple of spots using "release" where a use of gdb_bfd_ref_ptr would be cleaner. These will be fixed in the next patch. I think this patch fixes some latent bugs. For example, it seems to me that previously objfpy_add_separate_debug_file leaked a BFD. I'm not 100% certain that the macho_symfile_read_all_oso change is correct. The existing code here is hard for me to follow. One goal of this sort of automated reference counting, though, is to make it more difficult to make logic errors; so hopefully the code is clear now. 2017-01-10 Tom Tromey <tom@tromey.com> * windows-tdep.c (windows_xfer_shared_library): Update. * windows-nat.c (windows_make_so): Update. * utils.h (make_cleanup_bfd_unref): Remove. * utils.c (do_bfd_close_cleanup, make_cleanup_bfd_unref): Remove. * symfile.h (symfile_bfd_open) (find_separate_debug_file_in_section): Return gdb_bfd_ref_ptr. * symfile.c (read_symbols, symbol_file_add) (separate_debug_file_exists): Update. (symfile_bfd_open): Return gdb_bfd_ref_ptr. (generic_load, reread_symbols): Update. * symfile-mem.c (symbol_file_add_from_memory): Update. * spu-linux-nat.c (spu_bfd_open): Return gdb_bfd_ref_ptr. (spu_symbol_file_add_from_memory): Update. * solist.h (struct target_so_ops) <bfd_open>: Return gdb_bfd_ref_ptr. (solib_bfd_fopen, solib_bfd_open): Return gdb_bfd_ref_ptr. * solib.c (solib_bfd_fopen, solib_bfd_open): Return gdb_bfd_ref_ptr. (solib_map_sections, reload_shared_libraries_1): Update. * solib-svr4.c (enable_break): Update. * solib-spu.c (spu_bfd_fopen): Return gdb_bfd_ref_ptr. * solib-frv.c (enable_break2): Update. * solib-dsbt.c (enable_break): Update. * solib-darwin.c (gdb_bfd_mach_o_fat_extract): Return gdb_bfd_ref_ptr. (darwin_solib_get_all_image_info_addr_at_init): Update. (darwin_bfd_open): Return gdb_bfd_ref_ptr. * solib-aix.c (solib_aix_bfd_open): Return gdb_bfd_ref_ptr. * record-full.c (record_full_save): Update. * python/py-objfile.c (objfpy_add_separate_debug_file): Update. * procfs.c (insert_dbx_link_bpt_in_file): Update. * minidebug.c (find_separate_debug_file_in_section): Return gdb_bfd_ref_ptr. * machoread.c (macho_add_oso_symfile): Change abfd to gdb_bfd_ref_ptr. (macho_symfile_read_all_oso): Update. (macho_check_dsym): Return gdb_bfd_ref_ptr. (macho_symfile_read): Update. * jit.c (bfd_open_from_target_memory): Return gdb_bfd_ref_ptr. (jit_bfd_try_read_symtab): Update. * gdb_bfd.h (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr) (gdb_bfd_openw, gdb_bfd_openr_iovec) (gdb_bfd_openr_next_archived_file, gdb_bfd_fdopenr): Return gdb_bfd_ref_ptr. (gdb_bfd_ref_policy): New struct. (gdb_bfd_ref_ptr): New typedef. * gdb_bfd.c (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr) (gdb_bfd_openw, gdb_bfd_openr_iovec) (gdb_bfd_openr_next_archived_file, gdb_bfd_fdopenr): Return gdb_bfd_ref_ptr. * gcore.h (create_gcore_bfd): Return gdb_bfd_ref_ptr. * gcore.c (create_gcore_bfd): Return gdb_bfd_ref_ptr. (gcore_command): Update. * exec.c (exec_file_attach): Update. * elfread.c (elf_symfile_read): Update. * dwarf2read.c (dwarf2_get_dwz_file): Update. (try_open_dwop_file, open_dwo_file): Return gdb_bfd_ref_ptr. (open_and_init_dwo_file): Update. (open_dwp_file): Return gdb_bfd_ref_ptr. (open_and_init_dwp_file): Update. * corelow.c (core_open): Update. * compile/compile-object-load.c (compile_object_load): Update. * common/gdb_ref_ptr.h (ref_ptr::operator->): New operator. * coffread.c (coff_symfile_read): Update. * cli/cli-dump.c (bfd_openr_or_error, bfd_openw_or_error): Return gdb_bfd_ref_ptr. Rename. (dump_bfd_file, restore_command): Update. * build-id.h (build_id_to_debug_bfd): Return gdb_bfd_ref_ptr. * build-id.c (build_id_to_debug_bfd): Return gdb_bfd_ref_ptr. (find_separate_debug_file_by_buildid): Update.
2016-11-22 02:12:23 +08:00
#include "gdb_bfd.h"
Add DWARF index cache New in v3: - Remove things related to the dwarf-5 format. - Fix compilation on mingw (scoped_mmap.c). GDB can generate indexes for DWARF debug information, which, when integrated in the original binary, can speed up loading object files. This can be done using the gdb-add-index script or directly by the linker itself. However, not many people know about this. And even among those who do, because it requires additional steps, I don't know a lot of people who actually go through that trouble. To help make using the DWARF index more transparent, this patch introduces a DWARF index cache. When enabled, loading an index-less binary in GDB will automatically save an index file in ~/.cache/gdb. When loading that same object file again, the index file will be looked up and used to load the DWARF index. You therefore get the benefit of the DWARF index without having to do additional manual steps or modifying your build system. When an index section is already present in the file, GDB will prefer that one over looking up the cache. When doing my edit-compile-debug cycle, I often debug multiple times the same build, so the cache helps reducing the load time of the debug sessions after the first one. - The saved index file is exactly the same as the output of the "save gdb-index" command. It is therefore the exact same content that would be found in the .gdb_index or .debug_names section. We just leave it as a standalone file instead of merging it in the binary. - The cache is just a directory with files named after the object file's build-id. It is not possible to save/load the index for an object file without build-id in the cache. - The cache uses the gdb index format. The problem with the dwarf-5 format is that we can generate an addendum to the .debug_str section that you're supposed to integrate to the original binary. This complicates a little bit loading the data from the cached index files, so I would leave this for later. - The size taken up by ~/.cache/gdb is not limited. I was thinking we could add configurable limit (like ccache does), but that would come after. Also, maybe a command to flush the cache. - The cache is disabled by default. I think once it's been out there and tested for a while, it could be turned on by default, so that everybody can enjoy it. - The code was made to follow the XDG specification: if the XDG_CACHE_HOME environment variable, it is used, otherwise it falls back to ~/.cache/gdb. It is possible to change it using "set index-cache directory". On other OSes than GNU/Linux, ~/.cache may not be the best place to put such data. On macOS it should probably default to ~/Library/Caches/... On Windows, %LocalAppData%/... I don't intend to do this part, but further patches are welcome. - I think that we need to be careful that multiple instances of GDB don't interfere with each other (not far fetched at all if you run GDB in some automated script) and the cache is always coherent (either the file is not found, or it is found and entirely valid). Writing the file directly to its final location seems like a recipe for failure. One GDB could read a file in the index while it is being written by another GDB. To mitigate this, I made write_psymtabs_to_index write to temporary files and rename them once it's done. Two GDB instances writing the index for the same file should not step on each other's toes (the last file to be renamed will stay). A GDB looking up a file will only see a complete file or no file. Also, if GDB crashes while generating the index file, it will leave a work-in-progress file, but it won't be picked up by other instances looking up in the cache. gdb/ChangeLog: * common/pathstuff.h (get_standard_cache_dir): New. * common/pathstuff.c (get_standard_cache_dir): New. * build-id.h (build_id_to_string): New. * dwarf-index-common.h (INDEX4_SUFFIX, INDEX5_SUFFIX, DEBUG_STR_SUFFIX): Move to here. * dwarf-index-write.c (INDEX4_SUFFIX, INDEX5_SUFFIX, DEBUG_STR_SUFFIX): Move from there. (write_psymtabs_to_index): Make non-static, add basename parameter. Write to temporary files, rename when done. (save_gdb_index_command): Adjust call to write_psymtabs_to_index. * dwarf2read.h (dwarf2_per_objfile) <index_cache_res>: New field. * dwarf2read.c (dwz_file) <index_cache_res>: New field. (get_gdb_index_contents_from_cache): New. (get_gdb_index_contents_from_cache_dwz): New. (dwarf2_initialize_objfile): Read index from cache. (dwarf2_build_psymtabs): Save to index. * dwarf-index-cache.h: New file. * dwarf-index-cache.c: New file. * dwarf-index-write.h: New file. gdb/testsuite/ChangeLog: * boards/index-cache-gdb.exp: New file. * gdb.dwarf2/index-cache.exp: New file. * gdb.dwarf2/index-cache.c: New file. * gdb.base/maint.exp: Check if we are using the index cache.
2018-08-08 06:14:20 +08:00
#include "common/rsp-low.h"
Use class to manage BFD reference counts This introduces a new specialization of gdb::ref_ptr that can be used to manage BFD reference counts. Then it changes most places in gdb to use this new class, rather than explicit reference-counting or cleanups. This patch removes make_cleanup_bfd_unref. If you look you will see a couple of spots using "release" where a use of gdb_bfd_ref_ptr would be cleaner. These will be fixed in the next patch. I think this patch fixes some latent bugs. For example, it seems to me that previously objfpy_add_separate_debug_file leaked a BFD. I'm not 100% certain that the macho_symfile_read_all_oso change is correct. The existing code here is hard for me to follow. One goal of this sort of automated reference counting, though, is to make it more difficult to make logic errors; so hopefully the code is clear now. 2017-01-10 Tom Tromey <tom@tromey.com> * windows-tdep.c (windows_xfer_shared_library): Update. * windows-nat.c (windows_make_so): Update. * utils.h (make_cleanup_bfd_unref): Remove. * utils.c (do_bfd_close_cleanup, make_cleanup_bfd_unref): Remove. * symfile.h (symfile_bfd_open) (find_separate_debug_file_in_section): Return gdb_bfd_ref_ptr. * symfile.c (read_symbols, symbol_file_add) (separate_debug_file_exists): Update. (symfile_bfd_open): Return gdb_bfd_ref_ptr. (generic_load, reread_symbols): Update. * symfile-mem.c (symbol_file_add_from_memory): Update. * spu-linux-nat.c (spu_bfd_open): Return gdb_bfd_ref_ptr. (spu_symbol_file_add_from_memory): Update. * solist.h (struct target_so_ops) <bfd_open>: Return gdb_bfd_ref_ptr. (solib_bfd_fopen, solib_bfd_open): Return gdb_bfd_ref_ptr. * solib.c (solib_bfd_fopen, solib_bfd_open): Return gdb_bfd_ref_ptr. (solib_map_sections, reload_shared_libraries_1): Update. * solib-svr4.c (enable_break): Update. * solib-spu.c (spu_bfd_fopen): Return gdb_bfd_ref_ptr. * solib-frv.c (enable_break2): Update. * solib-dsbt.c (enable_break): Update. * solib-darwin.c (gdb_bfd_mach_o_fat_extract): Return gdb_bfd_ref_ptr. (darwin_solib_get_all_image_info_addr_at_init): Update. (darwin_bfd_open): Return gdb_bfd_ref_ptr. * solib-aix.c (solib_aix_bfd_open): Return gdb_bfd_ref_ptr. * record-full.c (record_full_save): Update. * python/py-objfile.c (objfpy_add_separate_debug_file): Update. * procfs.c (insert_dbx_link_bpt_in_file): Update. * minidebug.c (find_separate_debug_file_in_section): Return gdb_bfd_ref_ptr. * machoread.c (macho_add_oso_symfile): Change abfd to gdb_bfd_ref_ptr. (macho_symfile_read_all_oso): Update. (macho_check_dsym): Return gdb_bfd_ref_ptr. (macho_symfile_read): Update. * jit.c (bfd_open_from_target_memory): Return gdb_bfd_ref_ptr. (jit_bfd_try_read_symtab): Update. * gdb_bfd.h (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr) (gdb_bfd_openw, gdb_bfd_openr_iovec) (gdb_bfd_openr_next_archived_file, gdb_bfd_fdopenr): Return gdb_bfd_ref_ptr. (gdb_bfd_ref_policy): New struct. (gdb_bfd_ref_ptr): New typedef. * gdb_bfd.c (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr) (gdb_bfd_openw, gdb_bfd_openr_iovec) (gdb_bfd_openr_next_archived_file, gdb_bfd_fdopenr): Return gdb_bfd_ref_ptr. * gcore.h (create_gcore_bfd): Return gdb_bfd_ref_ptr. * gcore.c (create_gcore_bfd): Return gdb_bfd_ref_ptr. (gcore_command): Update. * exec.c (exec_file_attach): Update. * elfread.c (elf_symfile_read): Update. * dwarf2read.c (dwarf2_get_dwz_file): Update. (try_open_dwop_file, open_dwo_file): Return gdb_bfd_ref_ptr. (open_and_init_dwo_file): Update. (open_dwp_file): Return gdb_bfd_ref_ptr. (open_and_init_dwp_file): Update. * corelow.c (core_open): Update. * compile/compile-object-load.c (compile_object_load): Update. * common/gdb_ref_ptr.h (ref_ptr::operator->): New operator. * coffread.c (coff_symfile_read): Update. * cli/cli-dump.c (bfd_openr_or_error, bfd_openw_or_error): Return gdb_bfd_ref_ptr. Rename. (dump_bfd_file, restore_command): Update. * build-id.h (build_id_to_debug_bfd): Return gdb_bfd_ref_ptr. * build-id.c (build_id_to_debug_bfd): Return gdb_bfd_ref_ptr. (find_separate_debug_file_by_buildid): Update.
2016-11-22 02:12:23 +08:00
/* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
Allow gdb to find debug symbols file by build-id for PE file format also This promotes BFD's struct elf_build_id to the generic struct bfd_build_id, populated when an ELF or PE BFD is read. gdb is updated to use that, and to use the build-id to find symbols for PE files also. There is currently no generic way to extract the build-id from an object file, perhaps an option to objdump to do this might make sense? On x86_64-pc-cygwin, gdb's sepdebug.exp changes: -# of unsupported tests 1 +# of expected passes 90 I don't seem to get consistent testsuite runs on i686-linux-gnu, but there don't appear to be any regressions. bfd/ChangeLog: 2015-06-10 Jon Turney <jon.turney@dronecode.org.uk> * elf-bfd.h : Remove struct elf_build_id. * bfd.c : Add struct bfd_build_id. * bfd-in2.h: Regenerate. * elf.c (elfobj_grok_gnu_build_id): Update to use bfd_build_id. * libpei.h: Add protoype and macros for bfd_XXi_slurp_codeview_record. * peXXigen.c (_bfd_XXi_slurp_codeview_record): Make public * peicode.h (pe_bfd_read_buildid): Add. (pe_bfd_object_p): Use pe_bfd_read_buildid(). gdb/ChangeLog: 2015-06-10 Jon Turney <jon.turney@dronecode.org.uk> * build-id.c: Don't include elf-bfd.h. (build_id_bfd_get): Use bfd_build_id. (build_id_verify): Ditto. * build-id.h: Ditto. (find_separate_debug_file_by_buildid): Ditto. * python/py-objfile.c: Don't include elf-bfd.h. (objfpy_get_build_id) Use bfd_build_id. (objfpy_build_id_matches, objfpy_lookup_objfile_by_build_id): Ditto. * coffread.c: Include build-id.h. (coff_symfile_read): Try find_separate_debug_file_by_buildid. gdb/doc/ChangeLog: 2015-06-10 Jon Turney <jon.turney@dronecode.org.uk> * gdb.texinfo (Separate Debug Files): Document that PE is also supported. gdb/testsuite/ChangeLog: 2015-06-10 Jon Turney <jon.turney@dronecode.org.uk> * gdb.base/sepdebug.exp: Add EXEEXT where needed. * lib/gdb.exp (get_build_id): Teach how to extract build-id from a PE file. * lib/future.exp (gdb_find_objdump): Add gdb_find_objdump. Signed-off-by: Jon Turney <jon.turney@dronecode.org.uk>
2015-04-08 03:49:08 +08:00
extern const struct bfd_build_id *build_id_bfd_get (bfd *abfd);
fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
/* Return true if ABFD has NT_GNU_BUILD_ID matching the CHECK value.
Otherwise, issue a warning and return false. */
extern int build_id_verify (bfd *abfd,
size_t check_len, const bfd_byte *check);
/* Find and open a BFD given a build-id. If no BFD can be found,
return NULL. The returned reference to the BFD must be released by
the caller. */
Use class to manage BFD reference counts This introduces a new specialization of gdb::ref_ptr that can be used to manage BFD reference counts. Then it changes most places in gdb to use this new class, rather than explicit reference-counting or cleanups. This patch removes make_cleanup_bfd_unref. If you look you will see a couple of spots using "release" where a use of gdb_bfd_ref_ptr would be cleaner. These will be fixed in the next patch. I think this patch fixes some latent bugs. For example, it seems to me that previously objfpy_add_separate_debug_file leaked a BFD. I'm not 100% certain that the macho_symfile_read_all_oso change is correct. The existing code here is hard for me to follow. One goal of this sort of automated reference counting, though, is to make it more difficult to make logic errors; so hopefully the code is clear now. 2017-01-10 Tom Tromey <tom@tromey.com> * windows-tdep.c (windows_xfer_shared_library): Update. * windows-nat.c (windows_make_so): Update. * utils.h (make_cleanup_bfd_unref): Remove. * utils.c (do_bfd_close_cleanup, make_cleanup_bfd_unref): Remove. * symfile.h (symfile_bfd_open) (find_separate_debug_file_in_section): Return gdb_bfd_ref_ptr. * symfile.c (read_symbols, symbol_file_add) (separate_debug_file_exists): Update. (symfile_bfd_open): Return gdb_bfd_ref_ptr. (generic_load, reread_symbols): Update. * symfile-mem.c (symbol_file_add_from_memory): Update. * spu-linux-nat.c (spu_bfd_open): Return gdb_bfd_ref_ptr. (spu_symbol_file_add_from_memory): Update. * solist.h (struct target_so_ops) <bfd_open>: Return gdb_bfd_ref_ptr. (solib_bfd_fopen, solib_bfd_open): Return gdb_bfd_ref_ptr. * solib.c (solib_bfd_fopen, solib_bfd_open): Return gdb_bfd_ref_ptr. (solib_map_sections, reload_shared_libraries_1): Update. * solib-svr4.c (enable_break): Update. * solib-spu.c (spu_bfd_fopen): Return gdb_bfd_ref_ptr. * solib-frv.c (enable_break2): Update. * solib-dsbt.c (enable_break): Update. * solib-darwin.c (gdb_bfd_mach_o_fat_extract): Return gdb_bfd_ref_ptr. (darwin_solib_get_all_image_info_addr_at_init): Update. (darwin_bfd_open): Return gdb_bfd_ref_ptr. * solib-aix.c (solib_aix_bfd_open): Return gdb_bfd_ref_ptr. * record-full.c (record_full_save): Update. * python/py-objfile.c (objfpy_add_separate_debug_file): Update. * procfs.c (insert_dbx_link_bpt_in_file): Update. * minidebug.c (find_separate_debug_file_in_section): Return gdb_bfd_ref_ptr. * machoread.c (macho_add_oso_symfile): Change abfd to gdb_bfd_ref_ptr. (macho_symfile_read_all_oso): Update. (macho_check_dsym): Return gdb_bfd_ref_ptr. (macho_symfile_read): Update. * jit.c (bfd_open_from_target_memory): Return gdb_bfd_ref_ptr. (jit_bfd_try_read_symtab): Update. * gdb_bfd.h (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr) (gdb_bfd_openw, gdb_bfd_openr_iovec) (gdb_bfd_openr_next_archived_file, gdb_bfd_fdopenr): Return gdb_bfd_ref_ptr. (gdb_bfd_ref_policy): New struct. (gdb_bfd_ref_ptr): New typedef. * gdb_bfd.c (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr) (gdb_bfd_openw, gdb_bfd_openr_iovec) (gdb_bfd_openr_next_archived_file, gdb_bfd_fdopenr): Return gdb_bfd_ref_ptr. * gcore.h (create_gcore_bfd): Return gdb_bfd_ref_ptr. * gcore.c (create_gcore_bfd): Return gdb_bfd_ref_ptr. (gcore_command): Update. * exec.c (exec_file_attach): Update. * elfread.c (elf_symfile_read): Update. * dwarf2read.c (dwarf2_get_dwz_file): Update. (try_open_dwop_file, open_dwo_file): Return gdb_bfd_ref_ptr. (open_and_init_dwo_file): Update. (open_dwp_file): Return gdb_bfd_ref_ptr. (open_and_init_dwp_file): Update. * corelow.c (core_open): Update. * compile/compile-object-load.c (compile_object_load): Update. * common/gdb_ref_ptr.h (ref_ptr::operator->): New operator. * coffread.c (coff_symfile_read): Update. * cli/cli-dump.c (bfd_openr_or_error, bfd_openw_or_error): Return gdb_bfd_ref_ptr. Rename. (dump_bfd_file, restore_command): Update. * build-id.h (build_id_to_debug_bfd): Return gdb_bfd_ref_ptr. * build-id.c (build_id_to_debug_bfd): Return gdb_bfd_ref_ptr. (find_separate_debug_file_by_buildid): Update.
2016-11-22 02:12:23 +08:00
extern gdb_bfd_ref_ptr build_id_to_debug_bfd (size_t build_id_len,
const bfd_byte *build_id);
fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
/* Find the separate debug file for OBJFILE, by using the build-id
associated with OBJFILE's BFD. If successful, returns the file name for the
separate debug file, otherwise, return an empty string. */
fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
extern std::string find_separate_debug_file_by_buildid
(struct objfile *objfile);
fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
Add DWARF index cache New in v3: - Remove things related to the dwarf-5 format. - Fix compilation on mingw (scoped_mmap.c). GDB can generate indexes for DWARF debug information, which, when integrated in the original binary, can speed up loading object files. This can be done using the gdb-add-index script or directly by the linker itself. However, not many people know about this. And even among those who do, because it requires additional steps, I don't know a lot of people who actually go through that trouble. To help make using the DWARF index more transparent, this patch introduces a DWARF index cache. When enabled, loading an index-less binary in GDB will automatically save an index file in ~/.cache/gdb. When loading that same object file again, the index file will be looked up and used to load the DWARF index. You therefore get the benefit of the DWARF index without having to do additional manual steps or modifying your build system. When an index section is already present in the file, GDB will prefer that one over looking up the cache. When doing my edit-compile-debug cycle, I often debug multiple times the same build, so the cache helps reducing the load time of the debug sessions after the first one. - The saved index file is exactly the same as the output of the "save gdb-index" command. It is therefore the exact same content that would be found in the .gdb_index or .debug_names section. We just leave it as a standalone file instead of merging it in the binary. - The cache is just a directory with files named after the object file's build-id. It is not possible to save/load the index for an object file without build-id in the cache. - The cache uses the gdb index format. The problem with the dwarf-5 format is that we can generate an addendum to the .debug_str section that you're supposed to integrate to the original binary. This complicates a little bit loading the data from the cached index files, so I would leave this for later. - The size taken up by ~/.cache/gdb is not limited. I was thinking we could add configurable limit (like ccache does), but that would come after. Also, maybe a command to flush the cache. - The cache is disabled by default. I think once it's been out there and tested for a while, it could be turned on by default, so that everybody can enjoy it. - The code was made to follow the XDG specification: if the XDG_CACHE_HOME environment variable, it is used, otherwise it falls back to ~/.cache/gdb. It is possible to change it using "set index-cache directory". On other OSes than GNU/Linux, ~/.cache may not be the best place to put such data. On macOS it should probably default to ~/Library/Caches/... On Windows, %LocalAppData%/... I don't intend to do this part, but further patches are welcome. - I think that we need to be careful that multiple instances of GDB don't interfere with each other (not far fetched at all if you run GDB in some automated script) and the cache is always coherent (either the file is not found, or it is found and entirely valid). Writing the file directly to its final location seems like a recipe for failure. One GDB could read a file in the index while it is being written by another GDB. To mitigate this, I made write_psymtabs_to_index write to temporary files and rename them once it's done. Two GDB instances writing the index for the same file should not step on each other's toes (the last file to be renamed will stay). A GDB looking up a file will only see a complete file or no file. Also, if GDB crashes while generating the index file, it will leave a work-in-progress file, but it won't be picked up by other instances looking up in the cache. gdb/ChangeLog: * common/pathstuff.h (get_standard_cache_dir): New. * common/pathstuff.c (get_standard_cache_dir): New. * build-id.h (build_id_to_string): New. * dwarf-index-common.h (INDEX4_SUFFIX, INDEX5_SUFFIX, DEBUG_STR_SUFFIX): Move to here. * dwarf-index-write.c (INDEX4_SUFFIX, INDEX5_SUFFIX, DEBUG_STR_SUFFIX): Move from there. (write_psymtabs_to_index): Make non-static, add basename parameter. Write to temporary files, rename when done. (save_gdb_index_command): Adjust call to write_psymtabs_to_index. * dwarf2read.h (dwarf2_per_objfile) <index_cache_res>: New field. * dwarf2read.c (dwz_file) <index_cache_res>: New field. (get_gdb_index_contents_from_cache): New. (get_gdb_index_contents_from_cache_dwz): New. (dwarf2_initialize_objfile): Read index from cache. (dwarf2_build_psymtabs): Save to index. * dwarf-index-cache.h: New file. * dwarf-index-cache.c: New file. * dwarf-index-write.h: New file. gdb/testsuite/ChangeLog: * boards/index-cache-gdb.exp: New file. * gdb.dwarf2/index-cache.exp: New file. * gdb.dwarf2/index-cache.c: New file. * gdb.base/maint.exp: Check if we are using the index cache.
2018-08-08 06:14:20 +08:00
/* Return an hex-string representation of BUILD_ID. */
static inline std::string
build_id_to_string (const bfd_build_id *build_id)
{
gdb_assert (build_id != NULL);
return bin2hex (build_id->data, build_id->size);
}
fix PR symtab/15597 This patch fixes gdb PR symtab/15597. The bug is that the .gnu_debugaltlink section includes the build-id of the alt file, but gdb does not use it. This patch fixes the problem by changing gdb to do what it ought to always have done: verify the build id of the file found using the filename in .gnu_debugaltlink; and if that does not match, try to find the correct debug file using the build-id and debug-file-directory. This patch touches BFD. Previously, gdb had its own code for parsing .gnu_debugaltlink; I changed it to use the BFD functions after those were introduced. However, the BFD functions are incorrect -- they assume that .gnu_debugaltlink is formatted like .gnu_debuglink. However, it it is not. Instead, it consists of a file name followed by the build-id -- no alignment, and the build-id is not a CRC. Fixing this properly is a bit of a pain. But, because separate_alt_debug_file_exists just has a FIXME for the build-id case, I did not fix it properly. Instead I introduced a hack. This leaves BFD working just as well as it did before my patch. I'm willing to do something better here but I could use some guidance as to what. It seems that the build-id code in BFD is largely punted on. FWIW gdb is the only user of bfd_get_alt_debug_link_info outside of BFD itself. I moved the build-id logic out of elfread.c and into a new file. This seemed cleanest to me. Writing a test case was a bit of a pain. I added a couple new features to the DWARF assembler to handle this. Built and regtested on x86-64 Fedora 18. * bfd-in2.h: Rebuild. * opncls.c (bfd_get_alt_debug_link_info): Add buildid_len parameter. Change type of buildid_out. Update. (get_alt_debug_link_info_shim): New function. (bfd_follow_gnu_debuglink): Use it. * Makefile.in (SFILES): Add build-id.c. (HFILES_NO_SRCDIR): Add build-id.h. * build-id.c: New file, largely from elfread.c. Modified most functions. * build-id.h: New file. * dwarf2read.c (dwarf2_get_dwz_file): Update for change to bfd_get_alt_debug_link_info. Verify dwz file's build-id. Search for dwz file using build-id. * elfread.c (build_id_bfd_get, build_id_verify) (build_id_to_debug_filename, find_separate_debug_file): Remove. * gdb.dwarf2/dwzbuildid.exp: New file. * lib/dwarf.exp (Dwarf::_section): Add "flags" and "type" parameters. (Dwarf::_defer_output): Change "section" parameter to "section_spec"; update. (Dwarf::gnu_debugaltlink, Dwarf::_note, Dwarf::build_id): New procs.
2013-10-09 03:56:15 +08:00
#endif /* BUILD_ID_H */