When an LTO linker plugin claims an external member of a thin archive, gold
does not properly unlock the file and make its file descriptor available for
reuse. This patch fixes the problem by modifying Archive::include_member to
unlock the object file via an RAII class instance, ensuring that it will be
unlocked no matter what path is taken through the function.
gold/
PR gold/15660
* archive.cc (Thin_archive_object_unlocker): New class.
(Archive::include_member): Unlock external members of thin archives.
* testsuite/Makefile.am (plugin_test_1): Rename .syms files.
(plugin_test_2): Likewise.
(plugin_test_3): Likewise.
(plugin_test_4): Likewise.
(plugin_test_5): Likewise.
(plugin_test_6): Likewise.
(plugin_test_7): Likewise.
(plugin_test_8): Likewise.
(plugin_test_9): Likewise.
(plugin_test_10): Likewise.
(plugin_test_11): New test case.
* testsuite/Makefile.in: Regenerate.
* testsuite/plugin_test.c (claim_file_hook): Check for parallel .syms
file to decide whether to claim file.
(all_symbols_read_hook): Likewise.
* testsuite/plugin_test_1.sh: Adjust expected output.
* testsuite/plugin_test_2.sh: Likewise.
* testsuite/plugin_test_3.sh: Likewise.
* testsuite/plugin_test_6.sh: Likewise.
* testsuite/plugin_test_tls.sh: Likewise.
* testsuite/plugin_test_11.sh: New testcase.
readelf output for ELFv2 includes st_other bits specifying a
function's local entry offset.
* testsuite/plugin_test.c (parse_readelf_line): Skip non-visibility
st_other output.
* plugin-api.h
(ld_plugin_section): New struct.
(ld_plugin_get_section_count): New typedef.
(ld_plugin_get_section_type): New typedef.
(ld_plugin_get_section_name): New typedef.
(ld_plugin_get_section_contents): New typedef.
(ld_plugin_update_section_order): New typedef.
(ld_plugin_allow_section_ordering): New typedef.
(LDPT_GET_SECTION_COUNT): New enum value.
(LDPT_GET_SECTION_TYPE): New enum value.
(LDPT_GET_SECTION_NAME): New enum value.
(LDPT_GET_SECTION_CONTENTS): New enum value.
(LDPT_UPDATE_SECTION_ORDER): New enum value.
(LDPT_ALLOW_SECTION_ORDERING): New enum value.
(tv_get_section_count): New struct members.
(tv_get_section_type): New struct members.
(tv_get_section_name): New struct members.
(tv_get_section_contents): New struct members.
(tv_update_section_order): New struct members.
(tv_allow_section_ordering): New struct members.
* archive.cc (Archive::get_elf_object_for_member): Add extra parameter
to claim_file call.
* layout.cc (Layout::Layout): Initialize section_ordering_specified_,
input_section_position_, and input_section_glob_.
(read_layout_from_file): Call function section_ordering_specified.
* layout.h (is_section_ordering_specified): New function.
(section_ordering_specified): New function.
(section_ordering_specified_): New boolean member.
* main.cc(main): Call load_plugins after layout object is defined.
* output.cc (Output_section::add_input_section): Use
function section_ordering_specified to check if section ordering is
needed.
* output.cc (Output_section::add_relaxed_input_section): Use
function section_ordering_specified to check if section ordering is
needed.
(Output_section::update_section_layout): New function.
(Output_section::sort_attached_input_sections): Check if input section
must be reordered.
* output.h (Output_section::update_section_layout): New function.
* plugin.cc (get_section_count): New function.
(get_section_type): New function.
(get_section_name): New function.
(get_section_contents): New function.
(update_section_order): New function.
(allow_section_ordering): New function.
(Plugin::load): Add the new interfaces to the transfer vector.
(Plugin_manager::load_plugins): New parameter.
(Plugin_manager::all_symbols_read): New parameter.
(Plugin_manager::claim_file): New parameter. Save the elf object for
unclaimed objects.
(Plugin_manager::get_elf_object): New function.
(Plugin_manager::get_view): Change to directly use the bool to check
if get_view is called from claim_file_hook.
* plugin.h (input_objects): New function
(Plugin__manager::load_plugins): New parameter.
(Plugin_manager::claim_file): New parameter.
(Plugin_manager::get_elf_object): New function.
(Plugin_manager::in_claim_file_handler): New function.
(Plugin_manager::in_claim_file_handler_): New member.
(layout): New function.
* readsyms.cc (Read_symbols::do_read_symbols): Call the claim_file
handler with an extra parameter. Make the elf object before calling
claim_file handler.
* testsuite/plugin_test.c (get_section_count): New function pointer.
(get_section_type): New function pointer.
(get_section_name): New function pointer.
(get_section_contents): New function pointer.
(update_section_order): New function pointer.
(allow_section_ordering): New function pointer.
(onload): Check if the new interfaces exist.
to File_read::claim_for_plugin.
* descriptors.cc (Descriptors::open): Remove reference to
is_claimed.
(Descriptors::claim_for_plugin): Remove.
* descriptors.h (Descriptors::claim_for_plugin): Remove.
(Descriptors::is_claimed): Remove.
(claim_descriptor_for_plugin): Remove.
* fileread.cc (File_read::claim_for_plugin): Remove.
* fileread.h (File_read::claim_for_plugin): Remove.
(File_read::descriptor): Reopen descriptor if necessary.
* plugin.cc (Plugin::load): Add two new APIs to transfer vector.
(Plugin_manager::all_symbols_read): Add task parameter. Change
all callers.
(Plugin_manager::get_input_file): New function.
(Plugin_manager::release_input_file): New function.
(Pluginobj::Pluginobj): Add filesize parameter and initialize
corresponding data member.
(Sized_pluginobj::Sized_pluginobj): Add filesize parameter
and pass to base constructor. Change all callers.
(get_input_file, release_input_file): New functions.
(make_sized_plugin_object): Add filesize parameter. Change all callers.
* plugin.h (Plugin_manager::Plugin_manager): Initialize task_ member.
(Plugin_manager::all_symbols_read): Add task parameter.
(Plugin_manager::get_input_file): New function.
(Plugin_manager::release_input_file): New function.
(Plugin_manager::task_): New data member.
(Pluginobj::Pluginobj): Add filesize parameter.
(Pluginobj::filename): New function.
(Pluginobj::descriptor): New function.
(Pluginobj::filesize): New function.
(Pluginobj::filesize_): New data member.
(Sized_pluginobj::Sized_pluginobj): Add filesize parameter.
* readsyms.cc (Read_symbols::do_read_symbols): Remove call to
File_read::claim_for_plugin; use Object::unlock to unlock the file.
* testsuite/Makefile.am (plugin_test_4): New test case for plugins
with archive libraries.
* testsuite/Makefile.in: Regenerate.
* testsuite/plugin_test.c (struct sym_info): New type.
(get_input_file, release_input_file): New static variables.
(onload): Capture new transfer vector entries.
(claim_file_hook): Stop reading at end of file according to filesize.
Factor out parsing of readelf output into separate function.
(all_symbols_read_hook): Exercise get_input_file and release_input_file
APIs and get the source file name from the symbol table. Convert
source file name to corresponding object file name. Print info
message when adding new input files.
(parse_readelf_line): New function.
* testsuite/plugin_test_1.sh: Add checks for new info messages.
* testsuite/plugin_test_2.sh: Likewise.
* testsuite/plugin_test_3.sh: Likewise.
* testsuite/plugin_test_4.sh: New test case.
vector.
(Plugin_manager::claim_file): Create plugin object even if
plugin did not call the add_symbols callback.
(Plugin_obj::get_symbol_resolution_info): Guard against plugin
asking for more symbols than were added.
* testsuite/Makefile.am (plugin_test_1): Add test case with
no global symbols.
(empty.syms): New target.
* testsuite/Makefile.in: Regenerate.
* testsuite/plugin_test.c (claim_file_hook): Add new debug
message. Don't call add_symbols if no globals.
(all_symbols_read_hook): Don't provide replacement for empty
claimed file.
include/:
* plugin-api.h: New file.
gold/:
* configure.ac (plugins): Add --enable-plugins option.
* configure: Regenerate.
* config.in: Regenerate.
* Makefile.am (LIBDL): New variable.
(CCFILES): Add plugin.cc.
(HFILES): Add plugin.h.
(ldadd_var): Add LIBDL.
* Makefile.in: Regenerate.
* archive.cc: Include "plugin.h".
(Archive::setup): Don't preread archive symbols when using a plugin.
(Archive::get_file_and_offset): Add memsize parameter. Change callers.
(Archive::get_elf_object_for_member): Call plugin hooks for claiming
files.
(Archive::include_member): Add symbols from plugin objects.
* archive.h (Archive::get_file_and_offset): Add memsize parameter.
* descriptors.cc (Descriptors::open): Check for file descriptors
abandoned by plugins.
(Descriptors::claim_for_plugin): New function.
* descriptors.h (Descriptors::claim_for_plugin): New function.
(Open_descriptor::is_claimed): New field.
(claim_descriptor_for_plugin): New function.
* fileread.cc (File_read::claim_for_plugin): New function.
* fileread.h (File_read::claim_for_plugin): New function.
(File_read::descriptor): New function.
* gold.cc: Include "plugin.h".
(queue_initial_tasks): Add task to call plugin hooks for generating
new object files.
* main.cc: Include "plugin.h".
(main): Load plugin libraries.
* object.h (Pluginobj): Declare.
(Object::pluginobj): New function.
(Object::do_pluginobj): New function.
(Object::set_target): New function.
* options.cc: Include "plugin.h".
(General_options::parse_plugin): New function.
(General_options::General_options): Initialize plugins_ field.
(General_options::add_plugin): New function.
* options.h (Plugin_manager): Declare.
(General_options): Add --plugin option.
(General_options::has_plugins): New function.
(General_options::plugins): New function.
(General_options::add_plugin): New function.
(General_options::plugins_): New field.
* plugin.cc: New file.
* plugin.h: New file.
* readsyms.cc: Include "plugin.h".
(Read_symbols::do_read_symbols): Check for archive before checking
for ELF file. Call plugin hooks to claim files.
* resolve.cc (Symbol_table::resolve): Record when symbol is referenced
from a real object file; force override when processing replacement
files.
* symtab.cc (Symbol::init_fields): Initialize in_real_elf_ field.
(Symbol::init_base_object): Likewise.
(Symbol::init_base_output_data): Likewise.
(Symbol::init_base_output_segment): Likewise.
(Symbol::init_base_constant): Likewise.
(Symbol::init_base_undefined): Likewise.
(Symbol::output_section): Assert that object is not a plugin.
(Symbol_table::add_from_pluginobj): New function.
(Symbol_table::sized_finalize_symbol): Treat symbols from plugins as
undefined.
(Symbol_table::sized_write_globals): Likewise.
(Symbol_table::add_from_pluginobj): Instantiate template.
* symtab.h (Sized_pluginobj): Declare.
(Symbol::in_real_elf): New function.
(Symbol::set_in_real_elf): New function.
(Symbol::in_real_elf_): New field.
(Symbol_table::add_from_pluginobj): New function.
* testsuite/Makefile.am (AM_CFLAGS): New variable.
(LIBDL): New variable.
(LDADD): Add LIBDL.
(check_PROGRAMS): Add plugin_test_1 and plugin_test_2.
(check_SCRIPTS): Add plugin_test_1.sh and plugin_test_2.sh.
(check_DATA): Add plugin_test_1.err and plugin_test_2.err.
(MOSTLYCLEANFILES): Likewise.
* testsuite/Makefile.in: Regenerate.
* testsuite/plugin_test.c: New file.
* testsuite/plugin_test_1.sh: New file.
* testsuite/plugin_test_2.sh: New file.
