8 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Joel Brobecker
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b811d2c292 |
Update copyright year range in all GDB files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
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Tom Tromey
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268a13a5a3 |
Rename common to gdbsupport
This is the next patch in the ongoing series to move gdbsever to the top level. This patch just renames the "common" directory. The idea is to do this move in two parts: first rename the directory (this patch), then move the directory to the top. This approach makes the patches a bit more tractable. I chose the name "gdbsupport" for the directory. However, as this patch was largely written by sed, we could pick a new name without too much difficulty. Tested by the buildbot. gdb/ChangeLog 2019-07-09 Tom Tromey <tom@tromey.com> * contrib/ari/gdb_ari.sh: Change common to gdbsupport. * configure: Rebuild. * configure.ac: Change common to gdbsupport. * gdbsupport: Rename from common. * acinclude.m4: Change common to gdbsupport. * Makefile.in (CONFIG_SRC_SUBDIR, COMMON_SFILES) (HFILES_NO_SRCDIR, stamp-version, ALLDEPFILES): Change common to gdbsupport. * aarch64-tdep.c, ada-lang.c, ada-lang.h, agent.c, alloc.c, amd64-darwin-tdep.c, amd64-dicos-tdep.c, amd64-fbsd-nat.c, amd64-fbsd-tdep.c, amd64-linux-nat.c, amd64-linux-tdep.c, amd64-nbsd-tdep.c, amd64-obsd-tdep.c, amd64-sol2-tdep.c, amd64-tdep.c, amd64-windows-tdep.c, arch-utils.c, arch/aarch64-insn.c, arch/aarch64.c, arch/aarch64.h, arch/amd64.c, arch/amd64.h, arch/arm-get-next-pcs.c, arch/arm-linux.c, arch/arm.c, arch/i386.c, arch/i386.h, arch/ppc-linux-common.c, arch/riscv.c, arch/riscv.h, arch/tic6x.c, arm-tdep.c, auto-load.c, auxv.c, ax-gdb.c, ax-general.c, ax.h, breakpoint.c, breakpoint.h, btrace.c, btrace.h, build-id.c, build-id.h, c-lang.h, charset.c, charset.h, cli/cli-cmds.c, cli/cli-cmds.h, cli/cli-decode.c, cli/cli-dump.c, cli/cli-option.h, cli/cli-script.c, coff-pe-read.c, command.h, compile/compile-c-support.c, compile/compile-c.h, compile/compile-cplus-symbols.c, compile/compile-cplus-types.c, compile/compile-cplus.h, compile/compile-loc2c.c, compile/compile.c, completer.c, completer.h, contrib/ari/gdb_ari.sh, corefile.c, corelow.c, cp-support.c, cp-support.h, cp-valprint.c, csky-tdep.c, ctf.c, darwin-nat.c, debug.c, defs.h, disasm-selftests.c, disasm.c, disasm.h, dtrace-probe.c, dwarf-index-cache.c, dwarf-index-cache.h, dwarf-index-write.c, dwarf2-frame.c, dwarf2expr.c, dwarf2loc.c, dwarf2read.c, event-loop.c, event-top.c, exceptions.c, exec.c, extension.h, fbsd-nat.c, features/aarch64-core.c, features/aarch64-fpu.c, features/aarch64-pauth.c, features/aarch64-sve.c, features/i386/32bit-avx.c, features/i386/32bit-avx512.c, features/i386/32bit-core.c, features/i386/32bit-linux.c, features/i386/32bit-mpx.c, features/i386/32bit-pkeys.c, features/i386/32bit-segments.c, features/i386/32bit-sse.c, features/i386/64bit-avx.c, features/i386/64bit-avx512.c, features/i386/64bit-core.c, features/i386/64bit-linux.c, features/i386/64bit-mpx.c, features/i386/64bit-pkeys.c, features/i386/64bit-segments.c, features/i386/64bit-sse.c, features/i386/x32-core.c, features/riscv/32bit-cpu.c, features/riscv/32bit-csr.c, features/riscv/32bit-fpu.c, features/riscv/64bit-cpu.c, features/riscv/64bit-csr.c, features/riscv/64bit-fpu.c, features/tic6x-c6xp.c, features/tic6x-core.c, features/tic6x-gp.c, filename-seen-cache.h, findcmd.c, findvar.c, fork-child.c, gcore.c, gdb_bfd.c, gdb_bfd.h, gdb_proc_service.h, gdb_regex.c, gdb_select.h, gdb_usleep.c, gdbarch-selftests.c, gdbthread.h, gdbtypes.h, gnu-nat.c, go32-nat.c, guile/guile.c, guile/scm-ports.c, guile/scm-safe-call.c, guile/scm-type.c, i386-fbsd-nat.c, i386-fbsd-tdep.c, i386-go32-tdep.c, i386-linux-nat.c, i386-linux-tdep.c, i386-tdep.c, i387-tdep.c, ia64-libunwind-tdep.c, ia64-linux-nat.c, inf-child.c, inf-ptrace.c, infcall.c, infcall.h, infcmd.c, inferior-iter.h, inferior.c, inferior.h, inflow.c, inflow.h, infrun.c, infrun.h, inline-frame.c, language.h, linespec.c, linux-fork.c, linux-nat.c, linux-tdep.c, linux-thread-db.c, location.c, machoread.c, macrotab.h, main.c, maint.c, maint.h, memattr.c, memrange.h, mi/mi-cmd-break.h, mi/mi-cmd-env.c, mi/mi-cmd-stack.c, mi/mi-cmd-var.c, mi/mi-interp.c, mi/mi-main.c, mi/mi-parse.h, minsyms.c, mips-linux-tdep.c, namespace.h, nat/aarch64-linux-hw-point.c, nat/aarch64-linux-hw-point.h, nat/aarch64-linux.c, nat/aarch64-sve-linux-ptrace.c, nat/amd64-linux-siginfo.c, nat/fork-inferior.c, nat/linux-btrace.c, nat/linux-btrace.h, nat/linux-namespaces.c, nat/linux-nat.h, nat/linux-osdata.c, nat/linux-personality.c, nat/linux-procfs.c, nat/linux-ptrace.c, nat/linux-ptrace.h, nat/linux-waitpid.c, nat/mips-linux-watch.c, nat/mips-linux-watch.h, nat/ppc-linux.c, nat/x86-dregs.c, nat/x86-dregs.h, nat/x86-linux-dregs.c, nat/x86-linux.c, nto-procfs.c, nto-tdep.c, objfile-flags.h, objfiles.c, objfiles.h, obsd-nat.c, observable.h, osdata.c, p-valprint.c, parse.c, parser-defs.h, ppc-linux-nat.c, printcmd.c, probe.c, proc-api.c, procfs.c, producer.c, progspace.h, psymtab.h, python/py-framefilter.c, python/py-inferior.c, python/py-ref.h, python/py-type.c, python/python.c, record-btrace.c, record-full.c, record.c, record.h, regcache-dump.c, regcache.c, regcache.h, remote-fileio.c, remote-fileio.h, remote-sim.c, remote.c, riscv-tdep.c, rs6000-aix-tdep.c, rust-exp.y, s12z-tdep.c, selftest-arch.c, ser-base.c, ser-event.c, ser-pipe.c, ser-tcp.c, ser-unix.c, skip.c, solib-aix.c, solib-target.c, solib.c, source-cache.c, source.c, source.h, sparc-nat.c, spu-linux-nat.c, stack.c, stap-probe.c, symfile-add-flags.h, symfile.c, symfile.h, symtab.c, symtab.h, target-descriptions.c, target-descriptions.h, target-memory.c, target.c, target.h, target/waitstatus.c, target/waitstatus.h, thread-iter.h, thread.c, tilegx-tdep.c, top.c, top.h, tracefile-tfile.c, tracefile.c, tracepoint.c, tracepoint.h, tui/tui-io.c, ui-file.c, ui-out.h, unittests/array-view-selftests.c, unittests/child-path-selftests.c, unittests/cli-utils-selftests.c, unittests/common-utils-selftests.c, unittests/copy_bitwise-selftests.c, unittests/environ-selftests.c, unittests/format_pieces-selftests.c, unittests/function-view-selftests.c, unittests/lookup_name_info-selftests.c, unittests/memory-map-selftests.c, unittests/memrange-selftests.c, unittests/mkdir-recursive-selftests.c, unittests/observable-selftests.c, unittests/offset-type-selftests.c, unittests/optional-selftests.c, unittests/parse-connection-spec-selftests.c, unittests/ptid-selftests.c, unittests/rsp-low-selftests.c, unittests/scoped_fd-selftests.c, unittests/scoped_mmap-selftests.c, unittests/scoped_restore-selftests.c, unittests/string_view-selftests.c, unittests/style-selftests.c, unittests/tracepoint-selftests.c, unittests/unpack-selftests.c, unittests/utils-selftests.c, unittests/xml-utils-selftests.c, utils.c, utils.h, valarith.c, valops.c, valprint.c, value.c, value.h, varobj.c, varobj.h, windows-nat.c, x86-linux-nat.c, xml-support.c, xml-support.h, xml-tdesc.h, xstormy16-tdep.c, xtensa-linux-nat.c, dwarf2read.h: Change common to gdbsupport. gdb/gdbserver/ChangeLog 2019-07-09 Tom Tromey <tom@tromey.com> * configure: Rebuild. * configure.ac: Change common to gdbsupport. * acinclude.m4: Change common to gdbsupport. * Makefile.in (SFILES, OBS, GDBREPLAY_OBS, IPA_OBJS) (version-generated.c, gdbsupport/%-ipa.o, gdbsupport/%.o): Change common to gdbsupport. * ax.c, event-loop.c, fork-child.c, gdb_proc_service.h, gdbreplay.c, gdbthread.h, hostio-errno.c, hostio.c, i387-fp.c, inferiors.c, inferiors.h, linux-aarch64-tdesc-selftest.c, linux-amd64-ipa.c, linux-i386-ipa.c, linux-low.c, linux-tic6x-low.c, linux-x86-low.c, linux-x86-tdesc-selftest.c, linux-x86-tdesc.c, lynx-i386-low.c, lynx-low.c, mem-break.h, nto-x86-low.c, regcache.c, regcache.h, remote-utils.c, server.c, server.h, spu-low.c, symbol.c, target.h, tdesc.c, tdesc.h, thread-db.c, tracepoint.c, win32-i386-low.c, win32-low.c: Change common to gdbsupport. |
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Joel Brobecker
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42a4f53d2b |
Update copyright year range in all GDB files.
This commit applies all changes made after running the gdb/copyright.py script. Note that one file was flagged by the script, due to an invalid copyright header (gdb/unittests/basic_string_view/element_access/char/empty.cc). As the file was copied from GCC's libstdc++-v3 testsuite, this commit leaves this file untouched for the time being; a patch to fix the header was sent to gcc-patches first. gdb/ChangeLog: Update copyright year range in all GDB files. |
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Joel Brobecker
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e2882c8578 |
Update copyright year range in all GDB files
gdb/ChangeLog:
Update copyright year range in all GDB files
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Simon Marchi
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798a7429f9 |
Remove some unused variables
This patch removes some unused variables, found with -Wunused. I have not removed everything reported by -Wunused, because some expressions such as struct type *arg_type = check_typedef (value_type); in bfin-tdep.c could have an unexpected but important side-effect. I removed others that I considered more low-risk, such as: struct gdbarch *gdbarch = get_objfile_arch (objfile); I tested building with Python 2/Python 3/no Python, with/without expat, with/without libipt and with/without babeltrace. gdb/ChangeLog: * ada-lang.c (ada_collect_symbol_completion_matches): Remove unused variables. (ada_is_redundant_range_encoding): Likewise. * ada-varobj.c (ada_varobj_get_value_of_array_variable): Likewise. * alpha-tdep.c (alpha_software_single_step): Likewise. * arm-tdep.c (_initialize_arm_tdep): Likewise. * auto-load.c (info_auto_load_cmd): Likewise. * break-catch-syscall.c (insert_catch_syscall): Likewise. (remove_catch_syscall): Likewise. * breakpoint.c (condition_completer): Likewise. (clear_command): Likewise. (update_breakpoint_locations): Likewise. * btrace.c (btrace_disable): Likewise. (btrace_teardown): Likewise. (btrace_maint_update_pt_packets): Likewise. (maint_btrace_clear_cmd): Likewise. * cli/cli-decode.c (lookup_cmd_1): Likewise. (lookup_cmd_composition): Likewise. * cli/cli-dump.c (scan_filename): Likewise. (restore_command): Likewise. * compile/compile-loc2c.c (compute_stack_depth): Likewise. * compile/compile-object-load.c (compile_object_load): Likewise. * compile/compile-object-run.c (compile_object_run): Likewise. * compile/compile.c (compile_to_object): Likewise. * completer.c (filename_completer): Likewise. (complete_files_symbols): Likewise. (complete_expression): Likewise. * corelow.c (core_open): Likewise. * ctf.c (ctf_start): Likewise. (ctf_write_status): Likewise. (ctf_write_uploaded_tsv): Likewise. (ctf_write_definition_end): Likewise. (ctf_open_dir): Likewise. (ctf_xfer_partial): Likewise. (ctf_trace_find): Likewise. * disasm.c (gdb_pretty_print_disassembler::pretty_print_insn): Likewise. * dwarf2loc.c (allocate_piece_closure): Likewise. (indirect_pieced_value): Likewise. (dwarf2_evaluate_loc_desc_full): Likewise. * dwarf2read.c (dw2_expand_marked_cus): Likewise. (dw2_expand_symtabs_matching): Likewise. (dw2_map_symbol_filenames): Likewise. (read_and_check_comp_unit_head): Likewise. (read_cutu_die_from_dwo): Likewise. (lookup_dwo_unit): Likewise. (read_comp_units_from_section): Likewise. (dwarf2_compute_name): Likewise. (handle_DW_AT_stmt_list): Likewise. (create_cus_hash_table): Likewise. (create_dwp_v2_section): Likewise. (dwarf2_rnglists_process): Likewise. (dwarf2_ranges_process): Likewise. (dwarf2_record_block_ranges): Likewise. (is_vtable_name): Likewise. (read_formatted_entries): Likewise. (skip_form_bytes): Likewise. * elfread.c (elf_symtab_read): Likewise. * exec.c (exec_file_command): Likewise. * f-valprint.c (f_val_print): Likewise. (info_common_command_for_block): Likewise. * guile/guile.c (initialize_scheme_side): Likewise. * guile/scm-breakpoint.c (gdbscm_breakpoint_commands): Likewise. * guile/scm-cmd.c (cmdscm_completer): Likewise. (gdbscm_register_command_x): Likewise. * guile/scm-frame.c (gdbscm_frame_read_var): Likewise. * guile/scm-param.c (gdbscm_parameter_value): Likewise. * guile/scm-ports.c (file_port_magic): Likewise. * guile/scm-pretty-print.c (ppscm_search_pp_list): Likewise. (ppscm_pretty_print_one_value): Likewise. (ppscm_print_children): Likewise. * guile/scm-string.c (gdbscm_string_to_argv): Likewise. * guile/scm-symtab.c (gdbscm_sal_symtab): Likewise. * guile/scm-type.c (gdbscm_type_next_field_x): Likewise. * guile/scm-utils.c (gdbscm_parse_function_args): Likewise. * i386-tdep.c (i386_register_reggroup_p): Likewise. * infcmd.c (run_command_1): Likewise. (until_next_fsm_clean_up): Likewise. * linespec.c (linespec_complete): Likewise. (find_label_symbols): Likewise. * m2-valprint.c (m2_val_print): Likewise. * memattr.c (require_user_regions): Likewise. (lookup_mem_region): Likewise. (disable_mem_command): Likewise. (mem_delete): Likewise. * mep-tdep.c (mep_register_name): Likewise. (mep_analyze_prologue): Likewise. * mi/mi-cmd-file.c (mi_cmd_file_list_shared_libraries): Likewise. * mi/mi-interp.c (mi_on_sync_execution_done): Likewise. * mi/mi-main.c (mi_cmd_trace_frame_collected): Likewise. * microblaze-linux-tdep.c (microblaze_linux_init_abi): Likewise. * minidebug.c (lzma_open): Likewise. * minsyms.c (lookup_minimal_symbol): Likewise. * mips-linux-tdep.c (mips64_fill_fpregset): Likewise. * mips-tdep.c (mips_stub_frame_sniffer): Likewise. (mips_o64_return_value): Likewise. (mips_single_step_through_delay): Likewise. (_initialize_mips_tdep): Likewise. * nios2-tdep.c (nios2_push_dummy_call): Likewise. (nios2_software_single_step): Likewise. * parse.c (find_minsym_type_and_address): Likewise. * psymtab.c (psym_relocate): Likewise. * python/py-breakpoint.c (bppy_get_commands): Likewise. (gdbpy_breakpoint_modified): Likewise. * python/py-infevents.c (create_inferior_call_event_object): Likewise. * python/py-record-btrace.c (btpy_list_item): Likewise. * python/py-type.c (typy_str): Likewise. * python/py-value.c (valpy_call): Likewise. * python/python.c (do_start_initialization): Likewise. * record-btrace.c (record_btrace_insn_history_range): Likewise. (record_btrace_call_history_range): Likewise. (record_btrace_record_method): Likewise. (record_btrace_xfer_partial): Likewise. (btrace_get_frame_function): Likewise. * record-full.c (record_full_open): Likewise. * record.c (get_context_size): Likewise. * registry.h (DEFINE_REGISTRY): Likewise. * remote-fileio.c (remote_fileio_request): Likewise. * remote.c (remote_update_thread_list): Likewise. (remote_check_symbols): Likewise. (remote_commit_resume): Likewise. (remote_interrupt): Likewise. (remote_insert_breakpoint): Likewise. (compare_sections_command): Likewise. * rust-exp.y (super_name): Likewise. (lex_string): Likewise. (convert_ast_to_type): Likewise. (convert_ast_to_expression): Likewise. * rust-lang.c (rust_print_struct_def): Likewise. (rust_print_type): Likewise. (rust_evaluate_subexp): Likewise. * rx-tdep.c (rx_register_type): Likewise. * ser-event.c (serial_event_clear): Likewise. * serial.c (serial_open): Likewise. * spu-tdep.c (spu_overlay_new_objfile): Likewise. * symfile.c (section_is_overlay): Likewise. (overlay_unmapped_address): Likewise. (overlay_mapped_address): Likewise. (simple_overlay_update_1): Likewise. (simple_overlay_update): Likewise. * symtab.c (symbol_find_demangled_name): Likewise. (search_symbols): Likewise. * target-descriptions.c (tdesc_predefined_type): Likewise. * target.c (target_commit_resume): Likewise. * thread.c (print_selected_thread_frame): Likewise. * top.c (new_ui_command): Likewise. (gdb_readline_no_editing): Likewise. * tracefile-tfile.c (tfile_open): Likewise. * tracepoint.c (create_tsv_from_upload): Likewise. * utils.c (quit): Likewise. (defaulted_query): Likewise. * valarith.c (value_concat): Likewise. * xml-syscall.c (xml_list_syscalls_by_group): Likewise. * xml-tdesc.c (target_fetch_description_xml): Likewise. * xtensa-tdep.c (xtensa_pseudo_register_read): Likewise. (xtensa_pseudo_register_write): Likewise. gdb/gdbserver/ChangeLog: * regcache.c (registers_to_string): Remove unused variable. |
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Pedro Alves
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726e13564b |
Assume termios is available, remove support for termio and sgtty
This commit garbage collects the termio and sgtty support. GDB's terminal handling code still has support for the old termio and sgtty interfaces in addition to termios. However, I think it's pretty safe to assume that for a long, long time, Unix-like systems provide termios. GNU/Linux, Solaris, Cygwin, AIX, DJGPP, macOS and the BSDs all have had termios.h for many years. Looking around the web, I found discussions about FreeBSD folks trying to get rid of old sgtty.h a decade ago: https://lists.freebsd.org/pipermail/freebsd-hackers/2007-March/019983.html So I think support for termio and sgtty in GDB is just dead code that is never compiled anywhere and is just getting in the way. For example, serial_noflush_set_tty_state and the raw<->cooked concerns mentioned in inflow.c only exist because of sgtty (see hardwire_noflush_set_tty_state). Regtested on GNU/Linux. Confirmed that I can still build Solaris, DJGPP and AIX GDB and that the resulting GDBs still include the termios.h-guarded code. Confirmed mingw-w64 GDB still builds and skips the termios.h-guarded code. gdb/ChangeLog: 2017-11-06 Pedro Alves <palves@redhat.com> * Makefile.in (SER_HARDWIRE): Update comment. (HFILES_NO_SRCDIR): Remove gdb_termios.h. * common/gdb_termios.h: Delete file. * common/job-control.c: Include termios.h and unistd.h instead of gdb_termios.h. (gdb_setpgid): Remove HAVE_TERMIOS || TIOCGPGRP preprocessor check. (have_job_control): Check HAVE_TERMIOS_H instead of HAVE_TERMIOS. Remove sgtty code. * configure.ac: No longer check for termio.h and sgtty.h. * configure: Regenerate. * inflow.c: Include termios.h instead of gdb_termios.h. Replace PROCESS_GROUP_TYPE checks with HAVE_TERMIOS_H checks throughout. Replace PROCESS_GROUP_TYPE references with pid_t references throughout. (gdb_getpgrp): Delete. (set_initial_gdb_ttystate): Use tcgetpgrp instead of gdb_getpgrp. (child_terminal_inferior): Remove comment. Remove sgtty code. (child_terminal_ours_1): Use tcgetpgrp directly instead of gdb_getpgrp. Use serial_set_tty_state instead aof serial_noflush_set_tty_state. Remove sgtty code. * inflow.h: Include unistd.h instead of gdb_termios.h. Replace PROCESS_GROUP_TYPE check with HAVE_TERMIOS_H check. (inferior_process_group): Now returns pid_t. * ser-base.c (ser_base_noflush_set_tty_state): Delete. * ser-base.h (ser_base_noflush_set_tty_state): Delete. * ser-event.c (serial_event_ops): Update. * ser-go32.c (dos_noflush_set_tty_state): Delete. (dos_ops): Update. * ser-mingw.c (hardwire_ops, tty_ops, pipe_ops, tcp_ops): Update. * ser-pipe.c (pipe_ops): Update. * ser-tcp.c (tcp_ops): Update. * ser-unix.c: Include termios.h instead of gdb_termios.h. Remove HAVE_TERMIOS checks. [HAVE_TERMIO] (struct hardwire_ttystate): Delete. [HAVE_SGTTY] (struct hardwire_ttystate): Delete. (get_tty_state, set_tty_state): Drop termio and sgtty code, and assume termios. (hardwire_noflush_set_tty_state): Delete. (hardwire_print_tty_state, hardwire_drain_output) (hardwire_flush_output, hardwire_flush_input) (hardwire_send_break, hardwire_raw, hardwire_setbaudrate) (hardwire_setstopbits, hardwire_setparity): Drop termio and sgtty code, and assume termios. (hardwire_ops): Update. (_initialize_ser_hardwire): Remove HAVE_TERMIOS check. * serial.c (serial_noflush_set_tty_state): Delete. * serial.h (serial_noflush_set_tty_state): Delete. (serial_ops::noflush_set_tty_state): Delete. gdb/gdbserver/ChangeLog: 2017-11-06 Pedro Alves <palves@redhat.com> * configure.ac: No longer check for termio.h and sgtty.h. * configure: Regenerate. * remote-utils.c: Include termios.h instead of gdb_termios.h. (remote_open): Check HAVE_TERMIOS_H instead of HAVE_TERMIOS. Remove termio and sgtty code. |
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Joel Brobecker
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61baf725ec |
update copyright year range in GDB files
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
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Pedro Alves
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00340e1b91 |
Introduce a serial interface for select'able events
This patch adds a new "event" struct serial type, that is an
abstraction specifically for waking up blocking waits/selects,
implemented on top of a pipe on POSIX, and on top of a native Windows
event (CreateEvent, etc.) on Windows.
This will be used to plug signal handler / mainline code races.
For example, GDB can indefinitely delay handling a quit request if the
user presses Ctrl-C between the last QUIT call and the next (blocking)
gdb_select call in the event loop:
QUIT;
<<< press ctrl-c here and end up blocked in gdb_select
indefinitely.
gdb_select (...); // whoops, SIGINT was already handled, no EINTR.
A global alone (either the quit flag, or the "ready" flag of the async
signal handlers in the event loop) is not sufficient.
To plug races such as these on POSIX systems, we have to register some
waitable file descriptor in the set of files gdb_select waits on, and
write to it from the signal handler. This is classically a pipe, and
the pattern called the self-pipe trick. On Linux, it could be a more
efficient eventfd instead, but I'm sticking with a pipe for
simplifity, as we need it for portability anyway.
(Alternatively, we could use pselect/ppoll, and block signals until
the pselect. The latter is not a design I think GDB could use,
because we want the QUIT macro to be super cheap, as it is used in
loops. Plus, Windows.)
This is a "struct serial" because Windows's gdb_select relies on that.
Windows's gdb_select, our "select" replacement, knows how to wait on
all kinds of handles (regular files, pipes, sockets, console, etc.)
unlike the native Windows "select" function, which can only wait on
sockets. Each file descriptor for a "serial" type that is not
normally waitable with WaitForMultipleObjects must have a
corresponding struct serial instance. gdb_select then internally
looks up the struct serial instance that wraps each file descriptor,
and asks it for the corresponding Windows waitable handle.
We could use serial_pipe() to create a "struct serial"-wrapped pipe
that is usable everywhere, including Windows. That's what currently
python/python.c uses for cross-thread posting of events.
However, serial_write and serial_readchar are not designed to be
async-signal-safe on POSIX hosts. It's easier to bypass those when
setting/clearing the event source.
And writing and a serial pipe is a bit heavy weight on Windows.
gdb_select requires an extra thread to wait on the pipe and several
Windows events, when a single manual-reset Windows event, with no
extra thread is sufficient.
The intended usage is simply:
- Call make_serial_event to create a serial event object.
- From the signal handler call serial_event_set to set the event.
- From mainline code, have select/poll wait for serial_event_fd(), in
addition to whatever other files you're about to wait for.
gdb/ChangeLog:
2016-04-12 Pedro Alves <palves@redhat.com>
* Makefile.in (SFILES): Add ser-event.c.
(HFILES_NO_SRCDIR): Add ser-event.h.
(COMMON_OBS): Add ser-event.o.
* ser-event.c, ser-event.h: New files.
* serial.c (new_serial): New function, factored out from
(serial_fdopen_ops): ... this.
(serial_open_ops_1): New function, factored out from
(serial_open): ... this.
(serial_open_ops): New function.
* serial.h (struct serial): Forware declare.
(serial_open_ops): New declaration.
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