| /* Work with executable files, for GDB. |
| |
| Copyright (C) 1988-2021 Free Software Foundation, Inc. |
| |
| 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/>. */ |
| |
| #include "defs.h" |
| #include "frame.h" |
| #include "inferior.h" |
| #include "target.h" |
| #include "gdbcmd.h" |
| #include "language.h" |
| #include "filenames.h" |
| #include "symfile.h" |
| #include "objfiles.h" |
| #include "completer.h" |
| #include "value.h" |
| #include "exec.h" |
| #include "observable.h" |
| #include "arch-utils.h" |
| #include "gdbthread.h" |
| #include "progspace.h" |
| #include "progspace-and-thread.h" |
| #include "gdb_bfd.h" |
| #include "gcore.h" |
| #include "source.h" |
| #include "build-id.h" |
| |
| #include <fcntl.h> |
| #include "readline/tilde.h" |
| #include "gdbcore.h" |
| |
| #include <ctype.h> |
| #include <sys/stat.h> |
| #include "solist.h" |
| #include <algorithm> |
| #include "gdbsupport/pathstuff.h" |
| #include "cli/cli-style.h" |
| |
| void (*deprecated_file_changed_hook) (const char *); |
| |
| static const target_info exec_target_info = { |
| "exec", |
| N_("Local exec file"), |
| N_("Use an executable file as a target.\n\ |
| Specify the filename of the executable file.") |
| }; |
| |
| /* The target vector for executable files. */ |
| |
| struct exec_target final : public target_ops |
| { |
| const target_info &info () const override |
| { return exec_target_info; } |
| |
| strata stratum () const override { return file_stratum; } |
| |
| void close () override; |
| enum target_xfer_status xfer_partial (enum target_object object, |
| const char *annex, |
| gdb_byte *readbuf, |
| const gdb_byte *writebuf, |
| ULONGEST offset, ULONGEST len, |
| ULONGEST *xfered_len) override; |
| struct target_section_table *get_section_table () override; |
| void files_info () override; |
| |
| bool has_memory () override; |
| char *make_corefile_notes (bfd *, int *) override; |
| int find_memory_regions (find_memory_region_ftype func, void *data) override; |
| }; |
| |
| static exec_target exec_ops; |
| |
| /* How to handle a mismatch between the current exec file and the exec |
| file determined from target. */ |
| |
| static const char *const exec_file_mismatch_names[] |
| = {"ask", "warn", "off", NULL }; |
| enum exec_file_mismatch_mode |
| { |
| exec_file_mismatch_ask, exec_file_mismatch_warn, exec_file_mismatch_off |
| }; |
| static const char *exec_file_mismatch = exec_file_mismatch_names[0]; |
| static enum exec_file_mismatch_mode exec_file_mismatch_mode |
| = exec_file_mismatch_ask; |
| |
| /* Show command. */ |
| static void |
| show_exec_file_mismatch_command (struct ui_file *file, int from_tty, |
| struct cmd_list_element *c, const char *value) |
| { |
| fprintf_filtered (gdb_stdout, |
| _("exec-file-mismatch handling is currently \"%s\".\n"), |
| exec_file_mismatch_names[exec_file_mismatch_mode]); |
| } |
| |
| /* Set command. Change the setting for range checking. */ |
| static void |
| set_exec_file_mismatch_command (const char *ignore, |
| int from_tty, struct cmd_list_element *c) |
| { |
| for (enum exec_file_mismatch_mode mode = exec_file_mismatch_ask; |
| ; |
| mode = static_cast<enum exec_file_mismatch_mode>(1 + (int) mode)) |
| { |
| if (strcmp (exec_file_mismatch, exec_file_mismatch_names[mode]) == 0) |
| { |
| exec_file_mismatch_mode = mode; |
| return; |
| } |
| if (mode == exec_file_mismatch_off) |
| internal_error (__FILE__, __LINE__, |
| _("Unrecognized exec-file-mismatch setting: \"%s\""), |
| exec_file_mismatch); |
| } |
| } |
| |
| /* Whether to open exec and core files read-only or read-write. */ |
| |
| bool write_files = false; |
| static void |
| show_write_files (struct ui_file *file, int from_tty, |
| struct cmd_list_element *c, const char *value) |
| { |
| fprintf_filtered (file, _("Writing into executable and core files is %s.\n"), |
| value); |
| } |
| |
| |
| static void |
| exec_target_open (const char *args, int from_tty) |
| { |
| target_preopen (from_tty); |
| exec_file_attach (args, from_tty); |
| } |
| |
| /* Close and clear exec_bfd. If we end up with no target sections to |
| read memory from, this unpushes the exec_ops target. */ |
| |
| void |
| exec_close (void) |
| { |
| if (exec_bfd) |
| { |
| bfd *abfd = exec_bfd; |
| |
| gdb_bfd_unref (abfd); |
| |
| /* Removing target sections may close the exec_ops target. |
| Clear exec_bfd before doing so to prevent recursion. */ |
| exec_bfd = NULL; |
| exec_bfd_mtime = 0; |
| |
| remove_target_sections (&exec_bfd); |
| |
| xfree (exec_filename); |
| exec_filename = NULL; |
| } |
| } |
| |
| /* This is the target_close implementation. Clears all target |
| sections and closes all executable bfds from all program spaces. */ |
| |
| void |
| exec_target::close () |
| { |
| scoped_restore_current_program_space restore_pspace; |
| |
| for (struct program_space *ss : program_spaces) |
| { |
| set_current_program_space (ss); |
| clear_section_table (current_target_sections); |
| exec_close (); |
| } |
| } |
| |
| /* See gdbcore.h. */ |
| |
| void |
| try_open_exec_file (const char *exec_file_host, struct inferior *inf, |
| symfile_add_flags add_flags) |
| { |
| struct gdb_exception prev_err; |
| |
| /* exec_file_attach and symbol_file_add_main may throw an error if the file |
| cannot be opened either locally or remotely. |
| |
| This happens for example, when the file is first found in the local |
| sysroot (above), and then disappears (a TOCTOU race), or when it doesn't |
| exist in the target filesystem, or when the file does exist, but |
| is not readable. |
| |
| Even without a symbol file, the remote-based debugging session should |
| continue normally instead of ending abruptly. Hence we catch thrown |
| errors/exceptions in the following code. */ |
| try |
| { |
| /* We must do this step even if exec_file_host is NULL, so that |
| exec_file_attach will clear state. */ |
| exec_file_attach (exec_file_host, add_flags & SYMFILE_VERBOSE); |
| } |
| catch (gdb_exception_error &err) |
| { |
| if (err.message != NULL) |
| warning ("%s", err.what ()); |
| |
| prev_err = std::move (err); |
| } |
| |
| if (exec_file_host != NULL) |
| { |
| try |
| { |
| symbol_file_add_main (exec_file_host, add_flags); |
| } |
| catch (const gdb_exception_error &err) |
| { |
| if (!exception_print_same (prev_err, err)) |
| warning ("%s", err.what ()); |
| } |
| } |
| } |
| |
| /* See gdbcore.h. */ |
| |
| void |
| validate_exec_file (int from_tty) |
| { |
| /* If user asked to ignore the mismatch, do nothing. */ |
| if (exec_file_mismatch_mode == exec_file_mismatch_off) |
| return; |
| |
| const char *current_exec_file = get_exec_file (0); |
| struct inferior *inf = current_inferior (); |
| /* Try to determine a filename from the process itself. */ |
| const char *pid_exec_file = target_pid_to_exec_file (inf->pid); |
| bool build_id_mismatch = false; |
| |
| /* If we cannot validate the exec file, return. */ |
| if (current_exec_file == NULL || pid_exec_file == NULL) |
| return; |
| |
| /* Try validating via build-id, if available. This is the most |
| reliable check. */ |
| |
| /* In case current_exec_file was changed, reopen_exec_file ensures |
| an up to date build_id (will do nothing if the file timestamp |
| did not change). If exec file changed, reopen_exec_file has |
| allocated another file name, so get_exec_file again. */ |
| reopen_exec_file (); |
| current_exec_file = get_exec_file (0); |
| |
| const bfd_build_id *exec_file_build_id = build_id_bfd_get (exec_bfd); |
| if (exec_file_build_id != nullptr) |
| { |
| /* Prepend the target prefix, to force gdb_bfd_open to open the |
| file on the remote file system (if indeed remote). */ |
| std::string target_pid_exec_file |
| = std::string (TARGET_SYSROOT_PREFIX) + pid_exec_file; |
| |
| gdb_bfd_ref_ptr abfd (gdb_bfd_open (target_pid_exec_file.c_str (), |
| gnutarget, -1, false)); |
| if (abfd != nullptr) |
| { |
| const bfd_build_id *target_exec_file_build_id |
| = build_id_bfd_get (abfd.get ()); |
| |
| if (target_exec_file_build_id != nullptr) |
| { |
| if (exec_file_build_id->size == target_exec_file_build_id->size |
| && memcmp (exec_file_build_id->data, |
| target_exec_file_build_id->data, |
| exec_file_build_id->size) == 0) |
| { |
| /* Match. */ |
| return; |
| } |
| else |
| build_id_mismatch = true; |
| } |
| } |
| } |
| |
| if (build_id_mismatch) |
| { |
| std::string exec_file_target (pid_exec_file); |
| |
| /* In case the exec file is not local, exec_file_target has to point at |
| the target file system. */ |
| if (is_target_filename (current_exec_file) && !target_filesystem_is_local ()) |
| exec_file_target = TARGET_SYSROOT_PREFIX + exec_file_target; |
| |
| warning |
| (_("Build ID mismatch between current exec-file %ps\n" |
| "and automatically determined exec-file %ps\n" |
| "exec-file-mismatch handling is currently \"%s\""), |
| styled_string (file_name_style.style (), current_exec_file), |
| styled_string (file_name_style.style (), exec_file_target.c_str ()), |
| exec_file_mismatch_names[exec_file_mismatch_mode]); |
| if (exec_file_mismatch_mode == exec_file_mismatch_ask) |
| { |
| symfile_add_flags add_flags = SYMFILE_MAINLINE; |
| if (from_tty) |
| { |
| add_flags |= SYMFILE_VERBOSE; |
| add_flags |= SYMFILE_ALWAYS_CONFIRM; |
| } |
| try |
| { |
| symbol_file_add_main (exec_file_target.c_str (), add_flags); |
| exec_file_attach (exec_file_target.c_str (), from_tty); |
| } |
| catch (gdb_exception_error &err) |
| { |
| warning (_("loading %ps %s"), |
| styled_string (file_name_style.style (), |
| exec_file_target.c_str ()), |
| err.message != NULL ? err.what () : "error"); |
| } |
| } |
| } |
| } |
| |
| /* See gdbcore.h. */ |
| |
| void |
| exec_file_locate_attach (int pid, int defer_bp_reset, int from_tty) |
| { |
| char *exec_file_target; |
| symfile_add_flags add_flags = 0; |
| |
| /* Do nothing if we already have an executable filename. */ |
| if (get_exec_file (0) != NULL) |
| return; |
| |
| /* Try to determine a filename from the process itself. */ |
| exec_file_target = target_pid_to_exec_file (pid); |
| if (exec_file_target == NULL) |
| { |
| warning (_("No executable has been specified and target does not " |
| "support\n" |
| "determining executable automatically. " |
| "Try using the \"file\" command.")); |
| return; |
| } |
| |
| gdb::unique_xmalloc_ptr<char> exec_file_host |
| = exec_file_find (exec_file_target, NULL); |
| |
| if (defer_bp_reset) |
| add_flags |= SYMFILE_DEFER_BP_RESET; |
| |
| if (from_tty) |
| add_flags |= SYMFILE_VERBOSE; |
| |
| /* Attempt to open the exec file. */ |
| try_open_exec_file (exec_file_host.get (), current_inferior (), add_flags); |
| } |
| |
| /* Set FILENAME as the new exec file. |
| |
| This function is intended to be behave essentially the same |
| as exec_file_command, except that the latter will detect when |
| a target is being debugged, and will ask the user whether it |
| should be shut down first. (If the answer is "no", then the |
| new file is ignored.) |
| |
| This file is used by exec_file_command, to do the work of opening |
| and processing the exec file after any prompting has happened. |
| |
| And, it is used by child_attach, when the attach command was |
| given a pid but not a exec pathname, and the attach command could |
| figure out the pathname from the pid. (In this case, we shouldn't |
| ask the user whether the current target should be shut down -- |
| we're supplying the exec pathname late for good reason.) */ |
| |
| void |
| exec_file_attach (const char *filename, int from_tty) |
| { |
| /* First, acquire a reference to the current exec_bfd. We release |
| this at the end of the function; but acquiring it now lets the |
| BFD cache return it if this call refers to the same file. */ |
| gdb_bfd_ref_ptr exec_bfd_holder = gdb_bfd_ref_ptr::new_reference (exec_bfd); |
| |
| /* Remove any previous exec file. */ |
| exec_close (); |
| |
| /* Now open and digest the file the user requested, if any. */ |
| |
| if (!filename) |
| { |
| if (from_tty) |
| printf_unfiltered (_("No executable file now.\n")); |
| |
| set_gdbarch_from_file (NULL); |
| } |
| else |
| { |
| int load_via_target = 0; |
| const char *scratch_pathname, *canonical_pathname; |
| int scratch_chan; |
| struct target_section *sections = NULL, *sections_end = NULL; |
| char **matching; |
| |
| if (is_target_filename (filename)) |
| { |
| if (target_filesystem_is_local ()) |
| filename += strlen (TARGET_SYSROOT_PREFIX); |
| else |
| load_via_target = 1; |
| } |
| |
| gdb::unique_xmalloc_ptr<char> canonical_storage, scratch_storage; |
| if (load_via_target) |
| { |
| /* gdb_bfd_fopen does not support "target:" filenames. */ |
| if (write_files) |
| warning (_("writing into executable files is " |
| "not supported for %s sysroots"), |
| TARGET_SYSROOT_PREFIX); |
| |
| scratch_pathname = filename; |
| scratch_chan = -1; |
| canonical_pathname = scratch_pathname; |
| } |
| else |
| { |
| scratch_chan = openp (getenv ("PATH"), OPF_TRY_CWD_FIRST, |
| filename, write_files ? |
| O_RDWR | O_BINARY : O_RDONLY | O_BINARY, |
| &scratch_storage); |
| #if defined(__GO32__) || defined(_WIN32) || defined(__CYGWIN__) |
| if (scratch_chan < 0) |
| { |
| int first_errno = errno; |
| char *exename = (char *) alloca (strlen (filename) + 5); |
| |
| strcat (strcpy (exename, filename), ".exe"); |
| scratch_chan = openp (getenv ("PATH"), OPF_TRY_CWD_FIRST, |
| exename, write_files ? |
| O_RDWR | O_BINARY |
| : O_RDONLY | O_BINARY, |
| &scratch_storage); |
| if (scratch_chan < 0) |
| errno = first_errno; |
| } |
| #endif |
| if (scratch_chan < 0) |
| perror_with_name (filename); |
| |
| scratch_pathname = scratch_storage.get (); |
| |
| /* gdb_bfd_open (and its variants) prefers canonicalized |
| pathname for better BFD caching. */ |
| canonical_storage = gdb_realpath (scratch_pathname); |
| canonical_pathname = canonical_storage.get (); |
| } |
| |
| gdb_bfd_ref_ptr temp; |
| if (write_files && !load_via_target) |
| temp = gdb_bfd_fopen (canonical_pathname, gnutarget, |
| FOPEN_RUB, scratch_chan); |
| else |
| temp = gdb_bfd_open (canonical_pathname, gnutarget, scratch_chan); |
| exec_bfd = temp.release (); |
| |
| if (!exec_bfd) |
| { |
| error (_("\"%ps\": could not open as an executable file: %s."), |
| styled_string (file_name_style.style (), scratch_pathname), |
| bfd_errmsg (bfd_get_error ())); |
| } |
| |
| /* gdb_realpath_keepfile resolves symlinks on the local |
| filesystem and so cannot be used for "target:" files. */ |
| gdb_assert (exec_filename == NULL); |
| if (load_via_target) |
| exec_filename = xstrdup (bfd_get_filename (exec_bfd)); |
| else |
| exec_filename = gdb_realpath_keepfile (scratch_pathname).release (); |
| |
| if (!bfd_check_format_matches (exec_bfd, bfd_object, &matching)) |
| { |
| /* Make sure to close exec_bfd, or else "run" might try to use |
| it. */ |
| exec_close (); |
| error (_("\"%ps\": not in executable format: %s"), |
| styled_string (file_name_style.style (), scratch_pathname), |
| gdb_bfd_errmsg (bfd_get_error (), matching).c_str ()); |
| } |
| |
| if (build_section_table (exec_bfd, §ions, §ions_end)) |
| { |
| /* Make sure to close exec_bfd, or else "run" might try to use |
| it. */ |
| exec_close (); |
| error (_("\"%ps\": can't find the file sections: %s"), |
| styled_string (file_name_style.style (), scratch_pathname), |
| bfd_errmsg (bfd_get_error ())); |
| } |
| |
| exec_bfd_mtime = bfd_get_mtime (exec_bfd); |
| |
| validate_files (); |
| |
| set_gdbarch_from_file (exec_bfd); |
| |
| /* Add the executable's sections to the current address spaces' |
| list of sections. This possibly pushes the exec_ops |
| target. */ |
| add_target_sections (&exec_bfd, sections, sections_end); |
| xfree (sections); |
| |
| /* Tell display code (if any) about the changed file name. */ |
| if (deprecated_exec_file_display_hook) |
| (*deprecated_exec_file_display_hook) (filename); |
| } |
| |
| bfd_cache_close_all (); |
| gdb::observers::executable_changed.notify (); |
| } |
| |
| /* Process the first arg in ARGS as the new exec file. |
| |
| Note that we have to explicitly ignore additional args, since we can |
| be called from file_command(), which also calls symbol_file_command() |
| which can take multiple args. |
| |
| If ARGS is NULL, we just want to close the exec file. */ |
| |
| static void |
| exec_file_command (const char *args, int from_tty) |
| { |
| if (from_tty && target_has_execution |
| && !query (_("A program is being debugged already.\n" |
| "Are you sure you want to change the file? "))) |
| error (_("File not changed.")); |
| |
| if (args) |
| { |
| /* Scan through the args and pick up the first non option arg |
| as the filename. */ |
| |
| gdb_argv built_argv (args); |
| char **argv = built_argv.get (); |
| |
| for (; (*argv != NULL) && (**argv == '-'); argv++) |
| {; |
| } |
| if (*argv == NULL) |
| error (_("No executable file name was specified")); |
| |
| gdb::unique_xmalloc_ptr<char> filename (tilde_expand (*argv)); |
| exec_file_attach (filename.get (), from_tty); |
| } |
| else |
| exec_file_attach (NULL, from_tty); |
| } |
| |
| /* Set both the exec file and the symbol file, in one command. |
| What a novelty. Why did GDB go through four major releases before this |
| command was added? */ |
| |
| static void |
| file_command (const char *arg, int from_tty) |
| { |
| /* FIXME, if we lose on reading the symbol file, we should revert |
| the exec file, but that's rough. */ |
| exec_file_command (arg, from_tty); |
| symbol_file_command (arg, from_tty); |
| if (deprecated_file_changed_hook) |
| deprecated_file_changed_hook (arg); |
| } |
| |
| |
| /* Locate all mappable sections of a BFD file. |
| table_pp_char is a char * to get it through bfd_map_over_sections; |
| we cast it back to its proper type. */ |
| |
| static void |
| add_to_section_table (bfd *abfd, struct bfd_section *asect, |
| void *table_pp_char) |
| { |
| struct target_section **table_pp = (struct target_section **) table_pp_char; |
| flagword aflag; |
| |
| gdb_assert (abfd == asect->owner); |
| |
| /* Check the section flags, but do not discard zero-length sections, since |
| some symbols may still be attached to this section. For instance, we |
| encountered on sparc-solaris 2.10 a shared library with an empty .bss |
| section to which a symbol named "_end" was attached. The address |
| of this symbol still needs to be relocated. */ |
| aflag = bfd_section_flags (asect); |
| if (!(aflag & SEC_ALLOC)) |
| return; |
| |
| (*table_pp)->owner = NULL; |
| (*table_pp)->the_bfd_section = asect; |
| (*table_pp)->addr = bfd_section_vma (asect); |
| (*table_pp)->endaddr = (*table_pp)->addr + bfd_section_size (asect); |
| (*table_pp)++; |
| } |
| |
| /* See exec.h. */ |
| |
| void |
| clear_section_table (struct target_section_table *table) |
| { |
| xfree (table->sections); |
| table->sections = table->sections_end = NULL; |
| } |
| |
| /* Resize section table TABLE by ADJUSTMENT. |
| ADJUSTMENT may be negative, in which case the caller must have already |
| removed the sections being deleted. |
| Returns the old size. */ |
| |
| static int |
| resize_section_table (struct target_section_table *table, int adjustment) |
| { |
| int old_count; |
| int new_count; |
| |
| old_count = table->sections_end - table->sections; |
| |
| new_count = adjustment + old_count; |
| |
| if (new_count) |
| { |
| table->sections = XRESIZEVEC (struct target_section, table->sections, |
| new_count); |
| table->sections_end = table->sections + new_count; |
| } |
| else |
| clear_section_table (table); |
| |
| return old_count; |
| } |
| |
| /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR. |
| Returns 0 if OK, 1 on error. */ |
| |
| int |
| build_section_table (struct bfd *some_bfd, struct target_section **start, |
| struct target_section **end) |
| { |
| unsigned count; |
| |
| count = bfd_count_sections (some_bfd); |
| xfree (*start); |
| *start = XNEWVEC (struct target_section, count); |
| *end = *start; |
| bfd_map_over_sections (some_bfd, add_to_section_table, (char *) end); |
| |
| gdb_assert (*end <= *start + count); |
| |
| /* We could realloc the table, but it probably loses for most files. */ |
| return 0; |
| } |
| |
| /* Add the sections array defined by [SECTIONS..SECTIONS_END[ to the |
| current set of target sections. */ |
| |
| void |
| add_target_sections (void *owner, |
| struct target_section *sections, |
| struct target_section *sections_end) |
| { |
| int count; |
| struct target_section_table *table = current_target_sections; |
| |
| count = sections_end - sections; |
| |
| if (count > 0) |
| { |
| int space = resize_section_table (table, count); |
| int i; |
| |
| for (i = 0; i < count; ++i) |
| { |
| table->sections[space + i] = sections[i]; |
| table->sections[space + i].owner = owner; |
| } |
| |
| scoped_restore_current_pspace_and_thread restore_pspace_thread; |
| program_space *curr_pspace = current_program_space; |
| |
| /* If these are the first file sections we can provide memory |
| from, push the file_stratum target. Must do this in all |
| inferiors sharing the program space. */ |
| for (inferior *inf : all_inferiors ()) |
| { |
| if (inf->pspace != curr_pspace) |
| continue; |
| |
| if (inf->target_is_pushed (&exec_ops)) |
| continue; |
| |
| switch_to_inferior_no_thread (inf); |
| push_target (&exec_ops); |
| } |
| } |
| } |
| |
| /* Add the sections of OBJFILE to the current set of target sections. */ |
| |
| void |
| add_target_sections_of_objfile (struct objfile *objfile) |
| { |
| struct target_section_table *table = current_target_sections; |
| struct obj_section *osect; |
| int space; |
| unsigned count = 0; |
| struct target_section *ts; |
| |
| if (objfile == NULL) |
| return; |
| |
| /* Compute the number of sections to add. */ |
| ALL_OBJFILE_OSECTIONS (objfile, osect) |
| { |
| if (bfd_section_size (osect->the_bfd_section) == 0) |
| continue; |
| count++; |
| } |
| |
| if (count == 0) |
| return; |
| |
| space = resize_section_table (table, count); |
| |
| ts = table->sections + space; |
| |
| ALL_OBJFILE_OSECTIONS (objfile, osect) |
| { |
| if (bfd_section_size (osect->the_bfd_section) == 0) |
| continue; |
| |
| gdb_assert (ts < table->sections + space + count); |
| |
| ts->addr = obj_section_addr (osect); |
| ts->endaddr = obj_section_endaddr (osect); |
| ts->the_bfd_section = osect->the_bfd_section; |
| ts->owner = (void *) objfile; |
| |
| ts++; |
| } |
| } |
| |
| /* Remove all target sections owned by OWNER. |
| OWNER must be the same value passed to add_target_sections. */ |
| |
| void |
| remove_target_sections (void *owner) |
| { |
| struct target_section *src, *dest; |
| struct target_section_table *table = current_target_sections; |
| |
| gdb_assert (owner != NULL); |
| |
| dest = table->sections; |
| for (src = table->sections; src < table->sections_end; src++) |
| if (src->owner != owner) |
| { |
| /* Keep this section. */ |
| if (dest < src) |
| *dest = *src; |
| dest++; |
| } |
| |
| /* If we've dropped any sections, resize the section table. */ |
| if (dest < src) |
| { |
| int old_count; |
| |
| old_count = resize_section_table (table, dest - src); |
| |
| /* If we don't have any more sections to read memory from, |
| remove the file_stratum target from the stack of each |
| inferior sharing the program space. */ |
| if (old_count + (dest - src) == 0) |
| { |
| scoped_restore_current_pspace_and_thread restore_pspace_thread; |
| program_space *curr_pspace = current_program_space; |
| |
| for (inferior *inf : all_inferiors ()) |
| { |
| if (inf->pspace != curr_pspace) |
| continue; |
| |
| if (inf->pspace->target_sections.sections |
| != inf->pspace->target_sections.sections_end) |
| continue; |
| |
| switch_to_inferior_no_thread (inf); |
| unpush_target (&exec_ops); |
| } |
| } |
| } |
| } |
| |
| /* See exec.h. */ |
| |
| void |
| exec_on_vfork () |
| { |
| if (current_program_space->target_sections.sections |
| != current_program_space->target_sections.sections_end) |
| push_target (&exec_ops); |
| } |
| |
| |
| |
| enum target_xfer_status |
| exec_read_partial_read_only (gdb_byte *readbuf, ULONGEST offset, |
| ULONGEST len, ULONGEST *xfered_len) |
| { |
| /* It's unduly pedantic to refuse to look at the executable for |
| read-only pieces; so do the equivalent of readonly regions aka |
| QTro packet. */ |
| if (exec_bfd != NULL) |
| { |
| asection *s; |
| bfd_size_type size; |
| bfd_vma vma; |
| |
| for (s = exec_bfd->sections; s; s = s->next) |
| { |
| if ((s->flags & SEC_LOAD) == 0 |
| || (s->flags & SEC_READONLY) == 0) |
| continue; |
| |
| vma = s->vma; |
| size = bfd_section_size (s); |
| if (vma <= offset && offset < (vma + size)) |
| { |
| ULONGEST amt; |
| |
| amt = (vma + size) - offset; |
| if (amt > len) |
| amt = len; |
| |
| amt = bfd_get_section_contents (exec_bfd, s, |
| readbuf, offset - vma, amt); |
| |
| if (amt == 0) |
| return TARGET_XFER_EOF; |
| else |
| { |
| *xfered_len = amt; |
| return TARGET_XFER_OK; |
| } |
| } |
| } |
| } |
| |
| /* Indicate failure to find the requested memory block. */ |
| return TARGET_XFER_E_IO; |
| } |
| |
| /* Return all read-only memory ranges found in the target section |
| table defined by SECTIONS and SECTIONS_END, starting at (and |
| intersected with) MEMADDR for LEN bytes. */ |
| |
| static std::vector<mem_range> |
| section_table_available_memory (CORE_ADDR memaddr, ULONGEST len, |
| struct target_section *sections, |
| struct target_section *sections_end) |
| { |
| std::vector<mem_range> memory; |
| |
| for (target_section *p = sections; p < sections_end; p++) |
| { |
| if ((bfd_section_flags (p->the_bfd_section) & SEC_READONLY) == 0) |
| continue; |
| |
| /* Copy the meta-data, adjusted. */ |
| if (mem_ranges_overlap (p->addr, p->endaddr - p->addr, memaddr, len)) |
| { |
| ULONGEST lo1, hi1, lo2, hi2; |
| |
| lo1 = memaddr; |
| hi1 = memaddr + len; |
| |
| lo2 = p->addr; |
| hi2 = p->endaddr; |
| |
| CORE_ADDR start = std::max (lo1, lo2); |
| int length = std::min (hi1, hi2) - start; |
| |
| memory.emplace_back (start, length); |
| } |
| } |
| |
| return memory; |
| } |
| |
| enum target_xfer_status |
| section_table_read_available_memory (gdb_byte *readbuf, ULONGEST offset, |
| ULONGEST len, ULONGEST *xfered_len) |
| { |
| target_section_table *table = target_get_section_table (&exec_ops); |
| std::vector<mem_range> available_memory |
| = section_table_available_memory (offset, len, |
| table->sections, table->sections_end); |
| |
| normalize_mem_ranges (&available_memory); |
| |
| for (const mem_range &r : available_memory) |
| { |
| if (mem_ranges_overlap (r.start, r.length, offset, len)) |
| { |
| CORE_ADDR end; |
| enum target_xfer_status status; |
| |
| /* Get the intersection window. */ |
| end = std::min<CORE_ADDR> (offset + len, r.start + r.length); |
| |
| gdb_assert (end - offset <= len); |
| |
| if (offset >= r.start) |
| status = exec_read_partial_read_only (readbuf, offset, |
| end - offset, |
| xfered_len); |
| else |
| { |
| *xfered_len = r.start - offset; |
| status = TARGET_XFER_UNAVAILABLE; |
| } |
| return status; |
| } |
| } |
| |
| *xfered_len = len; |
| return TARGET_XFER_UNAVAILABLE; |
| } |
| |
| enum target_xfer_status |
| section_table_xfer_memory_partial (gdb_byte *readbuf, const gdb_byte *writebuf, |
| ULONGEST offset, ULONGEST len, |
| ULONGEST *xfered_len, |
| struct target_section *sections, |
| struct target_section *sections_end, |
| gdb::function_view<bool |
| (const struct target_section *)> match_cb) |
| { |
| int res; |
| struct target_section *p; |
| ULONGEST memaddr = offset; |
| ULONGEST memend = memaddr + len; |
| |
| gdb_assert (len != 0); |
| |
| for (p = sections; p < sections_end; p++) |
| { |
| struct bfd_section *asect = p->the_bfd_section; |
| bfd *abfd = asect->owner; |
| |
| if (match_cb != nullptr && !match_cb (p)) |
| continue; /* not the section we need. */ |
| if (memaddr >= p->addr) |
| { |
| if (memend <= p->endaddr) |
| { |
| /* Entire transfer is within this section. */ |
| if (writebuf) |
| res = bfd_set_section_contents (abfd, asect, |
| writebuf, memaddr - p->addr, |
| len); |
| else |
| res = bfd_get_section_contents (abfd, asect, |
| readbuf, memaddr - p->addr, |
| len); |
| |
| if (res != 0) |
| { |
| *xfered_len = len; |
| return TARGET_XFER_OK; |
| } |
| else |
| return TARGET_XFER_EOF; |
| } |
| else if (memaddr >= p->endaddr) |
| { |
| /* This section ends before the transfer starts. */ |
| continue; |
| } |
| else |
| { |
| /* This section overlaps the transfer. Just do half. */ |
| len = p->endaddr - memaddr; |
| if (writebuf) |
| res = bfd_set_section_contents (abfd, asect, |
| writebuf, memaddr - p->addr, |
| len); |
| else |
| res = bfd_get_section_contents (abfd, asect, |
| readbuf, memaddr - p->addr, |
| len); |
| if (res != 0) |
| { |
| *xfered_len = len; |
| return TARGET_XFER_OK; |
| } |
| else |
| return TARGET_XFER_EOF; |
| } |
| } |
| } |
| |
| return TARGET_XFER_EOF; /* We can't help. */ |
| } |
| |
| struct target_section_table * |
| exec_target::get_section_table () |
| { |
| return current_target_sections; |
| } |
| |
| enum target_xfer_status |
| exec_target::xfer_partial (enum target_object object, |
| const char *annex, gdb_byte *readbuf, |
| const gdb_byte *writebuf, |
| ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
| { |
| struct target_section_table *table = get_section_table (); |
| |
| if (object == TARGET_OBJECT_MEMORY) |
| return section_table_xfer_memory_partial (readbuf, writebuf, |
| offset, len, xfered_len, |
| table->sections, |
| table->sections_end); |
| else |
| return TARGET_XFER_E_IO; |
| } |
| |
| |
| void |
| print_section_info (struct target_section_table *t, bfd *abfd) |
| { |
| struct gdbarch *gdbarch = gdbarch_from_bfd (abfd); |
| struct target_section *p; |
| /* FIXME: 16 is not wide enough when gdbarch_addr_bit > 64. */ |
| int wid = gdbarch_addr_bit (gdbarch) <= 32 ? 8 : 16; |
| |
| printf_filtered ("\t`%ps', ", |
| styled_string (file_name_style.style (), |
| bfd_get_filename (abfd))); |
| wrap_here (" "); |
| printf_filtered (_("file type %s.\n"), bfd_get_target (abfd)); |
| if (abfd == exec_bfd) |
| { |
| /* gcc-3.4 does not like the initialization in |
| <p == t->sections_end>. */ |
| bfd_vma displacement = 0; |
| bfd_vma entry_point; |
| |
| for (p = t->sections; p < t->sections_end; p++) |
| { |
| struct bfd_section *psect = p->the_bfd_section; |
| |
| if ((bfd_section_flags (psect) & (SEC_ALLOC | SEC_LOAD)) |
| != (SEC_ALLOC | SEC_LOAD)) |
| continue; |
| |
| if (bfd_section_vma (psect) <= abfd->start_address |
| && abfd->start_address < (bfd_section_vma (psect) |
| + bfd_section_size (psect))) |
| { |
| displacement = p->addr - bfd_section_vma (psect); |
| break; |
| } |
| } |
| if (p == t->sections_end) |
| warning (_("Cannot find section for the entry point of %ps."), |
| styled_string (file_name_style.style (), |
| bfd_get_filename (abfd))); |
| |
| entry_point = gdbarch_addr_bits_remove (gdbarch, |
| bfd_get_start_address (abfd) |
| + displacement); |
| printf_filtered (_("\tEntry point: %s\n"), |
| paddress (gdbarch, entry_point)); |
| } |
| for (p = t->sections; p < t->sections_end; p++) |
| { |
| struct bfd_section *psect = p->the_bfd_section; |
| bfd *pbfd = psect->owner; |
| |
| printf_filtered ("\t%s", hex_string_custom (p->addr, wid)); |
| printf_filtered (" - %s", hex_string_custom (p->endaddr, wid)); |
| |
| /* FIXME: A format of "08l" is not wide enough for file offsets |
| larger than 4GB. OTOH, making it "016l" isn't desirable either |
| since most output will then be much wider than necessary. It |
| may make sense to test the size of the file and choose the |
| format string accordingly. */ |
| /* FIXME: i18n: Need to rewrite this sentence. */ |
| if (info_verbose) |
| printf_filtered (" @ %s", |
| hex_string_custom (psect->filepos, 8)); |
| printf_filtered (" is %s", bfd_section_name (psect)); |
| if (pbfd != abfd) |
| printf_filtered (" in %ps", |
| styled_string (file_name_style.style (), |
| bfd_get_filename (pbfd))); |
| printf_filtered ("\n"); |
| } |
| } |
| |
| void |
| exec_target::files_info () |
| { |
| if (exec_bfd) |
| print_section_info (current_target_sections, exec_bfd); |
| else |
| puts_filtered (_("\t<no file loaded>\n")); |
| } |
| |
| static void |
| set_section_command (const char *args, int from_tty) |
| { |
| struct target_section *p; |
| const char *secname; |
| unsigned seclen; |
| unsigned long secaddr; |
| char secprint[100]; |
| long offset; |
| struct target_section_table *table; |
| |
| if (args == 0) |
| error (_("Must specify section name and its virtual address")); |
| |
| /* Parse out section name. */ |
| for (secname = args; !isspace (*args); args++); |
| seclen = args - secname; |
| |
| /* Parse out new virtual address. */ |
| secaddr = parse_and_eval_address (args); |
| |
| table = current_target_sections; |
| for (p = table->sections; p < table->sections_end; p++) |
| { |
| if (!strncmp (secname, bfd_section_name (p->the_bfd_section), seclen) |
| && bfd_section_name (p->the_bfd_section)[seclen] == '\0') |
| { |
| offset = secaddr - p->addr; |
| p->addr += offset; |
| p->endaddr += offset; |
| if (from_tty) |
| exec_ops.files_info (); |
| return; |
| } |
| } |
| if (seclen >= sizeof (secprint)) |
| seclen = sizeof (secprint) - 1; |
| strncpy (secprint, secname, seclen); |
| secprint[seclen] = '\0'; |
| error (_("Section %s not found"), secprint); |
| } |
| |
| /* If we can find a section in FILENAME with BFD index INDEX, adjust |
| it to ADDRESS. */ |
| |
| void |
| exec_set_section_address (const char *filename, int index, CORE_ADDR address) |
| { |
| struct target_section *p; |
| struct target_section_table *table; |
| |
| table = current_target_sections; |
| for (p = table->sections; p < table->sections_end; p++) |
| { |
| if (filename_cmp (filename, |
| bfd_get_filename (p->the_bfd_section->owner)) == 0 |
| && index == p->the_bfd_section->index) |
| { |
| p->endaddr += address - p->addr; |
| p->addr = address; |
| } |
| } |
| } |
| |
| bool |
| exec_target::has_memory () |
| { |
| /* We can provide memory if we have any file/target sections to read |
| from. */ |
| return (current_target_sections->sections |
| != current_target_sections->sections_end); |
| } |
| |
| char * |
| exec_target::make_corefile_notes (bfd *obfd, int *note_size) |
| { |
| error (_("Can't create a corefile")); |
| } |
| |
| int |
| exec_target::find_memory_regions (find_memory_region_ftype func, void *data) |
| { |
| return objfile_find_memory_regions (this, func, data); |
| } |
| |
| void _initialize_exec (); |
| void |
| _initialize_exec () |
| { |
| struct cmd_list_element *c; |
| |
| if (!dbx_commands) |
| { |
| c = add_cmd ("file", class_files, file_command, _("\ |
| Use FILE as program to be debugged.\n\ |
| It is read for its symbols, for getting the contents of pure memory,\n\ |
| and it is the program executed when you use the `run' command.\n\ |
| If FILE cannot be found as specified, your execution directory path\n\ |
| ($PATH) is searched for a command of that name.\n\ |
| No arg means to have no executable file and no symbols."), &cmdlist); |
| set_cmd_completer (c, filename_completer); |
| } |
| |
| c = add_cmd ("exec-file", class_files, exec_file_command, _("\ |
| Use FILE as program for getting contents of pure memory.\n\ |
| If FILE cannot be found as specified, your execution directory path\n\ |
| is searched for a command of that name.\n\ |
| No arg means have no executable file."), &cmdlist); |
| set_cmd_completer (c, filename_completer); |
| |
| add_com ("section", class_files, set_section_command, _("\ |
| Change the base address of section SECTION of the exec file to ADDR.\n\ |
| This can be used if the exec file does not contain section addresses,\n\ |
| (such as in the a.out format), or when the addresses specified in the\n\ |
| file itself are wrong. Each section must be changed separately. The\n\ |
| ``info files'' command lists all the sections and their addresses.")); |
| |
| add_setshow_boolean_cmd ("write", class_support, &write_files, _("\ |
| Set writing into executable and core files."), _("\ |
| Show writing into executable and core files."), NULL, |
| NULL, |
| show_write_files, |
| &setlist, &showlist); |
| |
| add_setshow_enum_cmd ("exec-file-mismatch", class_support, |
| exec_file_mismatch_names, |
| &exec_file_mismatch, |
| _("\ |
| Set exec-file-mismatch handling (ask|warn|off)."), |
| _("\ |
| Show exec-file-mismatch handling (ask|warn|off)."), |
| _("\ |
| Specifies how to handle a mismatch between the current exec-file\n\ |
| loaded by GDB and the exec-file automatically determined when attaching\n\ |
| to a process:\n\n\ |
| ask - warn the user and ask whether to load the determined exec-file.\n\ |
| warn - warn the user, but do not change the exec-file.\n\ |
| off - do not check for mismatch.\n\ |
| \n\ |
| GDB detects a mismatch by comparing the build IDs of the files.\n\ |
| If the user confirms loading the determined exec-file, then its symbols\n\ |
| will be loaded as well."), |
| set_exec_file_mismatch_command, |
| show_exec_file_mismatch_command, |
| &setlist, &showlist); |
| |
| add_target (exec_target_info, exec_target_open, filename_completer); |
| } |