This patch does the conversion of to_xfer_partial from
LONGEST (*to_xfer_partial) (struct target_ops *ops,
enum target_object object, const char *annex,
gdb_byte *readbuf, const gdb_byte *writebuf,
ULONGEST offset, ULONGEST len);
to
enum target_xfer_status (*to_xfer_partial) (struct target_ops *ops,
enum target_object object, const char *annex,
gdb_byte *readbuf, const gdb_byte *writebuf,
ULONGEST offset, ULONGEST len, ULONGEST *xfered_len);
It changes to_xfer_partial return the transfer status and the transfered
length by *XFERED_LEN. Generally, the return status has three stats,
- TARGET_XFER_OK,
- TARGET_XFER_EOF,
- TARGET_XFER_E_XXXX,
See the comments to them in 'enum target_xfer_status'. Note that
Pedro suggested not name TARGET_XFER_DONE, as it is confusing,
compared with "TARGET_XFER_OK". We finally name it TARGET_XFER_EOF.
With this change, GDB core can handle unavailable data in a convenient
way.
The rationale behind this change was mentioned here
https://sourceware.org/ml/gdb-patches/2013-10/msg00761.html
Consider an object/value like this:
0 100 150 200 512
DDDDDDDDDDDxxxxxxxxxDDDDDD...DDIIIIIIIIIIII..III
where D is valid data, and xxx is unavailable data, and I is beyond
the end of the object (Invalid). Currently, if we start the
xfer at 0, requesting, say 512 bytes, we'll first get back 100 bytes.
The xfer machinery then retries fetching [100,512), and gets back
TARGET_XFER_E_UNAVAILABLE. That's sufficient when you're either
interested in either having the whole of the 512 bytes available,
or erroring out. But, in this scenario, we're interested in
the data at [150,512). The problem is that the last
TARGET_XFER_E_UNAVAILABLE gives us no indication where to
start the read next. We'd need something like:
get me [0,512) >>>
<<< here's [0,100), *xfered_len is 100, returns TARGET_XFER_OK
get me [100,512) >>> (**1)
<<< [100,150) is unavailable, *xfered_len is 50, return TARGET_XFER_E_UNAVAILABLE.
get me [150,512) >>>
<<< here's [150,200), *xfered_len is 50, return TARGET_XFER_OK.
get me [200,512) >>>
<<< no more data, return TARGET_XFER_EOF.
This naturally implies pushing down the decision of whether
to return TARGET_XFER_E_UNAVAILABLE or something else
down to the target. (Which kinds of leads back to tfile
itself reading from RO memory from file (though we could
export a function in exec.c for that that tfile delegates to,
instead of re-adding the old code).
Beside this change, we also add a macro TARGET_XFER_STATUS_ERROR_P to
check whether a status is an error or not, to stop using "status < 0".
This patch also eliminates the comparison between status and 0.
No target implementations to to_xfer_partial adapts this new
interface. The interface still behaves as before.
gdb:
2014-02-11 Yao Qi <yao@codesourcery.com>
* target.h (enum target_xfer_error): Rename to ...
(enum target_xfer_status): ... it. New. All users updated.
(enum target_xfer_status) <TARGET_XFER_OK>, <TARGET_XFER_EOF>:
New.
(TARGET_XFER_STATUS_ERROR_P): New macro.
(target_xfer_error_to_string): Remove declaration.
(target_xfer_status_to_string): Declare.
(target_xfer_partial_ftype): Adjust it.
(struct target_ops) <to_xfer_partial>: Return
target_xfer_status. Add argument xfered_len. Update
comments.
* target.c (target_xfer_error_to_string): Rename to ...
(target_xfer_status_to_string): ... it. New. All callers
updated.
(target_read_live_memory): Likewise. Call target_xfer_partial
instead of target_read.
(memory_xfer_live_readonly_partial): Return
target_xfer_status. Add argument xfered_len.
(raw_memory_xfer_partial): Likewise.
(memory_xfer_partial_1): Likewise.
(memory_xfer_partial): Likewise.
(target_xfer_partial): Likewise. Check *XFERED_LEN is set
properly. Update debug message.
(default_xfer_partial, current_xfer_partial): Likewise.
(target_write_partial): Likewise.
(target_read_partial): Likewise. All callers updated.
(read_whatever_is_readable): Likewise.
(target_write_with_progress): Likewise.
(target_read_alloc_1): Likewise.
* aix-thread.c (aix_thread_xfer_partial): Likewise.
* auxv.c (procfs_xfer_auxv): Likewise.
(ld_so_xfer_auxv, memory_xfer_auxv): Likewise.
* bfd-target.c (target_bfd_xfer_partial): Likewise.
* bsd-kvm.c (bsd_kvm_xfer_partial): Likewise.
* bsd-uthread.c (bsd_uthread_xfer_partia): Likewise.
* corefile.c (read_memory): Adjust.
* corelow.c (core_xfer_partial): Likewise.
* ctf.c (ctf_xfer_partial): Likewise.
* darwin-nat.c (darwin_read_dyld_info): Likewise. All callers
updated.
(darwin_xfer_partial): Likewise.
* exec.c (section_table_xfer_memory_partial): Likewise. All
callers updated.
(exec_xfer_partial): Likewise.
* exec.h (section_table_xfer_memory_partial): Update
declaration.
* gnu-nat.c (gnu_xfer_memory): Likewise. Assert 'res' is not
negative.
(gnu_xfer_partial): Likewise.
* ia64-hpux-nat.c (ia64_hpux_xfer_memory_no_bs): Likewise.
(ia64_hpux_xfer_memory, ia64_hpux_xfer_uregs): Likewise.
(ia64_hpux_xfer_solib_got): Likewise.
* inf-ptrace.c (inf_ptrace_xfer_partial): Likewise. Change
type of 'partial_len' to ULONGEST.
* inf-ttrace.c (inf_ttrace_xfer_partial): Likewise.
* linux-nat.c (linux_xfer_siginfo ): Likewise.
(linux_nat_xfer_partial): Likewise.
(linux_proc_xfer_partial, linux_xfer_partial): Likewise.
(linux_proc_xfer_spu, linux_nat_xfer_osdata): Likewise.
* monitor.c (monitor_xfer_memory): Likewise.
(monitor_xfer_partial): Likewise.
* procfs.c (procfs_xfer_partial): Likewise.
* record-btrace.c (record_btrace_xfer_partial): Likewise.
* record-full.c (record_full_xfer_partial): Likewise.
(record_full_core_xfer_partial): Likewise.
* remote-sim.c (gdbsim_xfer_memory): Likewise.
(gdbsim_xfer_partial): Likewise.
* remote.c (remote_write_bytes_aux): Likewise. All callers
updated.
(remote_write_bytes, remote_read_bytes): Likewise. All
callers updated.
(remote_flash_erase): Likewise. All callers updated.
(remote_write_qxfer): Likewise. All callers updated.
(remote_read_qxfer): Likewise. All callers updated.
(remote_xfer_partial): Likewise.
* rs6000-nat.c (rs6000_xfer_partial): Likewise.
(rs6000_xfer_shared_libraries): Likewise.
* sol-thread.c (sol_thread_xfer_partial): Likewise.
(sol_thread_xfer_partial): Likewise.
* sparc-nat.c (sparc_xfer_wcookie): Likewise.
(sparc_xfer_partial): Likewise.
* spu-linux-nat.c (spu_proc_xfer_spu): Likewise. All callers
updated.
(spu_xfer_partial): Likewise.
* spu-multiarch.c (spu_xfer_partial): Likewise.
* tracepoint.c (tfile_xfer_partial): Likewise.
* windows-nat.c (windows_xfer_memory): Likewise.
(windows_xfer_shared_libraries): Likewise.
(windows_xfer_partial): Likewise.
* valprint.c: Replace 'target_xfer_error' with
'target_xfer_status' in comments.
This patch fixes the target double-close problem (PR remote/15266),
and in the process removes pop_target entire (PR remote/15256).
The first issue is that pop_target calls target_close. However, it
then calls unpush_target, which also calls target_close. This means
targets must be able to be closed twice. Not only is this strange,
but it also directly contradicts the contract of to_xclose targets.
(We currently have just a single such target, and it is never pushed;
but I plan to add more, and so this latent bug is triggered.)
The second issue is that it seems to me that calling pop_target is
often unsafe. This is what cropped up in 15256, where the remote
target assumed that it could pop_target -- but there was another
target higher on the stack, leading to confusion.
But, it is always just as easy to call unpush_target as it is to call
pop_target; and it is also safer. So, removing pop_target seemed like
an improvement.
Finally, this adds an assertion to target_close to ensure that no
currently-pushed target can be closed.
Built and regtested on x86-64 Fedora 18; both natively and using the
native-gdbserver board file.
PR remote/15256, PR remote/15266:
* bfd-target.c (target_bfd_reopen): Initialize to_magic.
* monitor.c (monitor_detach): Use unpush_target.
* remote-m32r-sdi.c (m32r_detach): Use unpush_target.
* remote-mips.c (mips_detach): Use unpush_target. Don't
call mips_close.
* remote-sim.c (gdbsim_detach): Use unpush_target.
* target.c (pop_target): Remove.
(pop_all_targets_above): Don't call target_close.
(target_close): Assert that the target is unpushed.
* target.h (pop_target): Don't declare.
* tracepoint.c (tfile_open): Use unpush_target.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
gdb_bfd_unref.
(free_dwo_file): Use gdb_bfd_unref.
* cli/cli-dump.c: Include gdb_bfd.h.
(bfd_openw_with_cleanup): Use gdb_bfd_ref.
(bfd_openr_with_cleanup): Likewise.
* windows-nat.c (windows_make_so): Use gdb_bfd_ref,
gdb_bfd_unref.
* utils.c: Include gdb_bfd.h.
(do_bfd_close_cleanup): Use gdb_bfd_unref.
* symfile.c: Include gdb_bfd.h.
(separate_debug_file_exists): Use gdb_bfd_unref.
(bfd_open_maybe_remote): Use gdb_bfd_ref.
(symfile_bfd_open): Use gdb_bfd_ref, gdb_bfd_unref.
(generic_load): Use gdb_bfd_ref.
(reread_symbols): Use gdb_bfd_unref.
* symfile-mem.c: Include gdb_bfd.h.
(symbol_file_add_from_memory): Use make_cleanup_bfd_close.
* spu-linux-nat.c (spu_bfd_open): Use gdb_bfd_ref, gdb_bfd_unref.
* solib.c: Include gdb_bfd.h.
(solib_bfd_fopen): Use gdb_bfd_ref.
(solib_bfd_open): Use gdb_bfd_unref.
(free_so_symbols): Use gdb_bfd_unref.
(reload_shared_libraries_1): Use gdb_bfd_unref.
* solib-spu.c: Include gdb_bfd.h.
(spu_bfd_fopen): Use gdb_bfd_ref, gdb_bfd_unref.
* solib-pa64.c (pa64_solib_create_inferior_hook): Use gdb_bfd_ref,
gdb_bfd_unref.
* solib-frv.c: Include gdb_bfd.h.
(enable_break2): Use gdb_bfd_unref.
* solib-dsbt.c: Include gdb_bfd.h.
(enable_break2): Use gdb_bfd_unref.
* solib-darwin.c: Include gdb_bfd.h.
(darwin_solib_get_all_image_info_addr_at_init): Use gdb_bfd_ref,
gdb_bfd_unref.
(darwin_bfd_open): Use gdb_bfd_unref.
* rs6000-nat.c (add_vmap): Use gdb_bfd_ref, gdb_bfd_unref.
* remote-mips.c: Include gdb_bfd.h.
(mips_load_srec): Use gdb_bfd_ref.
(pmon_load_fast): Use gdb_bfd_ref.
* remote-m32r-sdi.c: Include gdb_bfd.h.
(m32r_load): Use gdb_bfd_ref.
* record.c: Include gdb_bfd.h.
(record_save_cleanups): Use gdb_bfd_unref.
(cmd_record_save): Use gdb_bfd_unref.
* procfs.c (insert_dbx_link_bpt_in_file): Use gdb_bfd_ref,
gdb_bfd_unref.
* objfiles.h (gdb_bfd_close_or_warn): Remove.
(gdb_bfd_ref, gdb_bfd_unref): Move to gdb_bfd.h.
* objfiles.c: Include gdb_bfd.h.
(free_objfile): Use gdb_bfd_unref.
(gdb_bfd_close_or_warn, gdb_bfd_ref, gdb_bfd_unref): Move to
gdb_bfd.c.
* machoread.c (macho_add_oso_symfile): Use gdb_bfd_unref.
(macho_symfile_read_all_oso): Use gdb_bfd_ref, gdb_bfd_unref.
(macho_check_dsym): Likewise.
* m32r-rom.c: Include gdb_bfd.h.
(m32r_load): Use gdb_bfd_ref.
(m32r_upload_command): Use gdb_bfd_ref.
* jit.c: Include gdb_bfd.h.
(jit_bfd_try_read_symtab): Use gdb_bfd_ref, gdb_bfd_unref.
* gdb_bfd.h: New file.
* gdb_bfd.c: New file.
* gcore.c: Include gdb_bfd.h.
(create_gcore_bfd): Use gdb_bfd_ref.
(do_bfd_delete_cleanup): Use gdb_bfd_unref.
(gcore_command): Use gdb_bfd_unref.
* exec.c: Include gdb_bfd.h.
(exec_close): Use gdb_bfd_unref.
(exec_close_1): Use gdb_bfd_unref.
(exec_file_attach): Use gdb_bfd_ref.
* elfread.c: Include gdb_bfd.h.
(build_id_verify): Use gdb_bfd_unref.
* dsrec.c: Include gdb_bfd.h.
(load_srec): Use gdb_bfd_ref.
* corelow.c: Include gdb_bfd.h.
(core_close): Use gdb_bfd_unref.
(core_open): Use gdb_bfd_ref.
* bfd-target.c: Include gdb_bfd.h.
(target_bfd_xclose): Use gdb_bfd_unref.
(target_bfd_reopen): Use gdb_bfd_ref.
* Makefile.in (SFILES): Add gdb_bfd.c.
(HFILES_NO_SRCDIR): Add gdb_bfd.h.
(COMMON_OBS): Add gdb_bfd.o.
(target_bfd_xfer_partial): Adjust to get at the section table from
the new structure.
(target_bfd_get_section_table): Ditto.
(target_bfd_xclose): Ditto. Get the bfd pointer from the
target_bfd_data structure, from the section table.
(target_bfd_reopen): Store a struct target_bfd_data in the
target_ops to_data field, instead of a target_section_table.
(update_current_target): Don't inherit to_sections or
to_sections_end.
(target_get_section_table): New.
(target_section_by_addr): Fetch the section table from the passed
in target.
(memory_xfer_partial): Handle unmapped overlay sections before
anything else. Get the overlay mapped address here. Adjust to
use section_table_xfer_memory_partial.
(get_target_memory): Request a TARGET_OBJECT_RAW_MEMORY object
instead of TARGET_OBJECT_MEMORY.
(target_resize_to_sections): Delete.
(remove_target_sections): Adjust to remove target sections from
`current_target_sections', and use resize_section_table.
* target.h (struct target_ops) <to_sections, to_sections_end>:
Remove fields.
<to_get_section_table>: New method.
(xfer_memory, print_section_info): Delete declarations.
(struct target_section_table): New type.
(target_get_section_table): Declare.
(target_resize_to_sections): Delete declaration.
(remove_target_sections): Delete declaration.
* bfd-target.c (target_bfd_xfer_partial): Get the section table
from to_data.
(target_bfd_get_section_table): New.
(target_bfd_xclose): Adjust.
(target_bfd_reopen): Store the section table in the to_data field.
* corelow.c (core_data): New.
(core_close): Adjust to release core_data and its sections.
(core_open): Allocate core_data, and build its target sections
table.
(deprecated_core_resize_section_table): New.
(core_files_info): Pass core_data to print_section_info.
(core_xfer_partial): Adjust to use
section_table_xfer_memory_partial for TARGET_OBJECT_MEMORY xfers.
(init_core_ops): Do not install a deprecated_xfer_memory callback
anymore.
* solib.c (update_solib_list): Add the shared library sections
to the current target sections table.
* exec.c (current_target_sections_1): New global.
(current_target_sections): New global.
(exec_close_1): New function, refactored from exec_close. Remove
the exec_bfd's sections from the current target sections table.
Adjust to not use to_sections.
(exec_close): Remove all target sections. Call exec_close_1.
(exec_file_clear): Use exec_close_1 instead of unpushing the
target.
(exec_file_attach): Likewise. Adjust to not use to_sections. Add
exec_bfd's sections to the current target sections table. Don't
push the exec_ops target here.
(resize_section_table): New.
(add_target_sections): New.
(remove_target_sections): Moved here.
(section_table_xfer_memory): Adjust to implement the xfer_partial
interface, and rename to...
(section_table_xfer_memory_partial): ... this, replacing the
current function of that same name.
(exec_get_section_table): New.
(exec_xfer_partial): New.
(xfer_memory): Delete.
(print_section_info): Replace the target_ops parameter by a
target_section_table parameter.
(exec_files_info, set_section_command, exec_set_section_address):
Adjust to use the current sections table.
(init_exec_ops): Do not register a deprecated_xfer_memory
callback. Register to_xfer_partial and to_get_section_table
callbacks.
* infrun.c (handle_inferior_event): Update comments around
solib_add.
* rs6000-nat.c (xcoff_relocate_core): Adjust to use
deprecated_core_resize_section_table.
* exec.h (resize_section_table): Declare.
(section_table_xfer_memory_partial): Add const char * argument.
(remove_target_sections): Declare here.
(add_target_sections): Declare.
(print_section_info): Declare here.
* gdbcore.h (deprecated_core_resize_section_table): Declare.
Include exec.h.
(struct section_closure): Delete.
(add_to_section_table): Delete.
(build_target_sections_from_bfd): Delete.
(target_bfd_xfer_partial): Use section_table_xfer_memory_partial.
(target_bfd_reopen): Use build_section_table.
* exec.c (xfer_memory): Move most code except for overlay
debugging support from here...
(section_table_xfer_memory): ... to this new function.
(section_table_xfer_memory_partial): New.
* exec.h (section_table_xfer_memory_partial): Declare.
* bfd-target.h (build_target_sections_from_bfd): Delete
declaration.
Silence a few -Wmissing-prototypes warnings.
PR build/9877:
* amd64-nat.c: Include "amd64-nat.h".
* fork-child.c (_initialize_fork_child): Ditto.
* gcore.c (_initialize_gcore): Ditto.
* inf-ptrace.c: Include "inf-ptrace.h".
(inf_ptrace_store_registers): Make it static.
* linux-nat.c (linux_nat_terminal_ours): Make it static.
(_initialize_linux_nat): Declare before definition.
* linux-tdep.c: Include "linux-tdep.h".
* linux-thread-db.c (_initialize_thread_db): Declare before
definition.
* proc-service.c (_initialize_proc_service): Ditto.
* remote.c (remote_send_printf): Make it static.
* solib.c: Include "solib.h".
* symfile-mem.c (_initialize_symfile_mem): Declare before
definition.
* ada-lang.c (ada_la_decode, ada_match_name)
(ada_suppress_symbol_printing, ada_is_array_type)
(ada_value_ptr_subscript, ada_array_length)
(ada_to_static_fixed_value): Make them static.
(_initialize_ada_language): Declare before definition.
* ada-tasks.c (ada_get_task_number, ada_get_environment_task)
(ada_task_list_changed, ada_new_objfile_observer): Make them
static.
(_initialize_tasks): Declare before definition.
* addrmap.c (_initialize_addrmap): Declare before definition.
* auxv.c (default_auxv_parse): Make it static.
* bfd-target.c (target_bfd_xfer_partial, target_bfd_xclose): Make
them static.
* breakpoint.c (remove_sal): Add line break.
(expand_line_sal_maybe): Make it static.
* cp-name-parser.y: Include "cp-support.h".
* cp-valprint.c (cp_find_class_member): Make it static.
* eval.c (value_f90_subarray): Ditto.
* exceptions.c (print_any_exception): Ditto.
* findcmd.c (_initialize_mem_search): Declare before definition.
* frame.c (frame_observer_target_changed): Make it static.
* gnu-v3-abi.c (gnuv3_find_method_in): Make it static.
* inf-child.c: Include "inf-child.h".
* inferior.h (valid_inferior_id): Rename to ...
(valid_gdb_inferior_id): ... this.
* infrun.c (infrun_thread_stop_requested, siginfo_make_value):
Make them static.
* jv-lang.c (java_language_arch_info): Make it static.
* m2-typeprint.c (m2_get_discrete_bounds): Ditto.
* osdata.c (info_osdata_command): Make it static.
* regcache.c (regcache_observer_target_changed): Make it static.
* reverse.c (_initialize_reverse): Declare before definition.
* stabsread.c (cleanup_undefined_types_noname)
(cleanup_undefined_types_1): Make them static.
* symfile.c (place_section): Make it static.
* symtab.c (find_pc_sect_psymtab_closer): Make it static.
* target-descriptions.c (_initialize_target_descriptions): Declare
before definition.
* target.c (default_get_ada_task_ptid, find_default_can_async_p)
(find_default_is_async_p, find_default_supports_non_stop): Make
them static.
(target_supports_non_stop): Add prototype.
(dummy_pid_to_str): Make it static.
* utils.c (_initialize_utils): Declare before definition.
* ada-exp.y (_initialize_ada_exp): Declare before definition.
* solib-svr4.c (HAS_LM_DYNAMIC_FROM_LINK_MAP): Add a prototype.
* target.h (struct target_ops): Add a prototype to the
to_can_execute_reverse callback.
* macroscope.c (_initialize_macroscope): Declare before definition.
* cp-namespace.c (_initialize_cp_namespace): Declare before definition.
* python/python.c (_initialize_python): Declare before definition.
* tui/tui-command.c: Include "tui/tui-command.h".
* tui/tui-data.c (init_content_element, init_win_info): Make them
static.
* tui/tui-disasm.c: Include "tui/tui-disasm.h".
* tui/tui-interp.c (_initialize_tui_interp): Declare before
definition.
* tui/tui-layout.c: Include "tui/tui-layout.h".
(_initialize_tui_layout): Declare before definition.
* tui/tui-regs.c: Include "tui/tui-regs.h".
(tui_display_reg_element_at_line): Make it static.
(_initialize_tui_regs): Declare before definition.
* tui/tui-stack.c (_initialize_tui_stack): Declare before
definition.
* tui/tui-win.c: Include "tui/tui-win.h".
(_initialize_tui_win): Declare before definition.
(tui_sigwinch_handler): Make it static. Wrap in ifdef SIGWINCH.
* tui/tui-win.h (tui_sigwinch_handler): Delete declaration.
(tui_get_cmd_list): Add a prototype.
* tui/tui-windata.c: Include tui-windata.h.
* tui/tui-wingeneral.c (box_win): Make it static.
* cli/cli-logging.c (show_logging_command): Make it static.
(_initialize_cli_logging): Declare before definition.
* mi/mi-common.c (_initialize_gdb_mi_common): Declare before
definition.
writebuf to `gdb_byte *'.
* sparc-nat.c (sparc_xfer_wcookie, sparc_xfer_partial): Change
type of readbuf and writebuf to `gdb_byte *'.
* bsd-uthread.c (bsd_uthread_xfer_partial): Change type of readbuf
and writebuf to `gdb_byte *'.
* inf-ptrace.c (inf_ptrace_xfer_partial): Change type of readbuf
and writebuf to `gdb_byte *'.
* bsd-kvm.c (bsd_kvm_xfer_memory): Replace.
(bsd_kvm_xfer_partial): New function.
(bsd_kvm_add_target): Set to_xfer_partial instead of
to_xfer_memory.
* bfd-target.c (target_bfd_xfer_partial): Change type of readbuf
and writebuf to `gdb_byte *'.
* target.c (deprecated_debug_xfer_memory): Remove prototype.
(deprecated_debug_xfer_memory): Change type of second argument to
`gdb_byte *'.
* remote.c (remote_xfer_memory): Remove prototype.
(remote_xfer_memory): Change type of second argument to `gdb_byte
*'.
(remote_xfer_partial): Change type of readbuf and writebuf to
`gdb_byte *'.
