X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fexec.c;h=92c87e4e02f096c2ec04bf305465649c876153f8;hb=1c5c938ad860811644774ecea66e044110967cf2;hp=809a0b2f8fe10b728dda4f81364a8ba8148785e9;hpb=b55e14c72c74ad4bcab302f9a81651ced881c415;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/exec.c b/gdb/exec.c index 809a0b2f8f..92c87e4e02 100644 --- a/gdb/exec.c +++ b/gdb/exec.c @@ -1,6 +1,6 @@ /* Work with executable files, for GDB. - Copyright (C) 1988-2014 Free Software Foundation, Inc. + Copyright (C) 1988-2017 Free Software Foundation, Inc. This file is part of GDB. @@ -34,15 +34,16 @@ #include "gdbthread.h" #include "progspace.h" #include "gdb_bfd.h" +#include "gcore.h" #include #include "readline/readline.h" -#include - #include "gdbcore.h" #include #include +#include "solist.h" +#include void (*deprecated_file_changed_hook) (char *); @@ -60,10 +61,7 @@ void _initialize_exec (void); /* The target vector for executable files. */ -struct target_ops exec_ops; - -/* True if the exec target is pushed on the stack. */ -static int using_exec_ops; +static struct target_ops exec_ops; /* Whether to open exec and core files read-only or read-write. */ @@ -78,7 +76,7 @@ show_write_files (struct ui_file *file, int from_tty, static void -exec_open (char *args, int from_tty) +exec_open (const char *args, int from_tty) { target_preopen (from_tty); exec_file_attach (args, from_tty); @@ -112,29 +110,17 @@ exec_close (void) sections and closes all executable bfds from all program spaces. */ static void -exec_close_1 (void) +exec_close_1 (struct target_ops *self) { - using_exec_ops = 0; - - { - struct program_space *ss; - struct cleanup *old_chain; + struct program_space *ss; + scoped_restore_current_program_space restore_pspace; - old_chain = save_current_program_space (); - ALL_PSPACES (ss) + ALL_PSPACES (ss) { set_current_program_space (ss); - - /* Delete all target sections. */ - resize_section_table - (current_target_sections, - -resize_section_table (current_target_sections, 0)); - + clear_section_table (current_target_sections); exec_close (); } - - do_cleanups (old_chain); - } } void @@ -147,6 +133,102 @@ exec_file_clear (int from_tty) printf_unfiltered (_("No executable file now.\n")); } +/* See exec.h. */ + +void +try_open_exec_file (const char *exec_file_host, struct inferior *inf, + symfile_add_flags add_flags) +{ + struct cleanup *old_chain; + struct gdb_exception prev_err = exception_none; + + old_chain = make_cleanup (free_current_contents, &prev_err.message); + + /* 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 (err, RETURN_MASK_ERROR) + { + if (err.message != NULL) + warning ("%s", err.message); + + prev_err = err; + + /* Save message so it doesn't get trashed by the catch below. */ + if (err.message != NULL) + prev_err.message = xstrdup (err.message); + } + END_CATCH + + if (exec_file_host != NULL) + { + TRY + { + symbol_file_add_main (exec_file_host, add_flags); + } + CATCH (err, RETURN_MASK_ERROR) + { + if (!exception_print_same (prev_err, err)) + warning ("%s", err.message); + } + END_CATCH + } + + do_cleanups (old_chain); +} + +/* See gdbcore.h. */ + +void +exec_file_locate_attach (int pid, int defer_bp_reset, int from_tty) +{ + char *exec_file_target, *exec_file_host; + struct cleanup *old_chain; + 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; + } + + exec_file_host = exec_file_find (exec_file_target, NULL); + old_chain = make_cleanup (xfree, exec_file_host); + + 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, current_inferior (), add_flags); + do_cleanups (old_chain); +} + /* Set FILENAME as the new exec file. This function is intended to be behave essentially the same @@ -165,8 +247,14 @@ exec_file_clear (int from_tty) we're supplying the exec pathname late for good reason.) */ void -exec_file_attach (char *filename, int from_tty) +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 (exec_bfd); + gdb_bfd_ref_ptr exec_bfd_holder (exec_bfd); + /* Remove any previous exec file. */ exec_close (); @@ -181,50 +269,87 @@ exec_file_attach (char *filename, int from_tty) } else { - struct cleanup *cleanups; - char *scratch_pathname, *canonical_pathname; + int load_via_target = 0; + const char *scratch_pathname, *canonical_pathname; int scratch_chan; struct target_section *sections = NULL, *sections_end = NULL; char **matching; - scratch_chan = openp (getenv ("PATH"), OPF_TRY_CWD_FIRST, filename, - write_files ? O_RDWR | O_BINARY : O_RDONLY | O_BINARY, - &scratch_pathname); -#if defined(__GO32__) || defined(_WIN32) || defined(__CYGWIN__) - if (scratch_chan < 0) + if (is_target_filename (filename)) { - char *exename = alloca (strlen (filename) + 5); + if (target_filesystem_is_local ()) + filename += strlen (TARGET_SYSROOT_PREFIX); + else + load_via_target = 1; + } - 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_pathname); + gdb::unique_xmalloc_ptr 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 + { + char *temp_pathname; + + scratch_chan = openp (getenv ("PATH"), OPF_TRY_CWD_FIRST, + filename, write_files ? + O_RDWR | O_BINARY : O_RDONLY | O_BINARY, + &temp_pathname); +#if defined(__GO32__) || defined(_WIN32) || defined(__CYGWIN__) + if (scratch_chan < 0) + { + 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, + &temp_pathname); + } #endif - if (scratch_chan < 0) - perror_with_name (filename); + if (scratch_chan < 0) + perror_with_name (filename); - cleanups = make_cleanup (xfree, scratch_pathname); + scratch_storage.reset (temp_pathname); + scratch_pathname = temp_pathname; - /* gdb_bfd_open (and its variants) prefers canonicalized pathname for - better BFD caching. */ - canonical_pathname = gdb_realpath (scratch_pathname); - make_cleanup (xfree, canonical_pathname); + /* gdb_bfd_open (and its variants) prefers canonicalized + pathname for better BFD caching. */ + canonical_storage = gdb_realpath (scratch_pathname); + canonical_pathname = canonical_storage.get (); + } - if (write_files) - exec_bfd = gdb_bfd_fopen (canonical_pathname, gnutarget, - FOPEN_RUB, scratch_chan); + gdb_bfd_ref_ptr temp; + if (write_files && !load_via_target) + temp = gdb_bfd_fopen (canonical_pathname, gnutarget, + FOPEN_RUB, scratch_chan); else - exec_bfd = gdb_bfd_open (canonical_pathname, gnutarget, scratch_chan); + temp = gdb_bfd_open (canonical_pathname, gnutarget, scratch_chan); + exec_bfd = temp.release (); if (!exec_bfd) { - error (_("\"%s\": could not open as an executable file: %s"), + error (_("\"%s\": could not open as an executable file: %s."), 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); - exec_filename = gdb_realpath_keepfile (scratch_pathname); + 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)) { @@ -260,9 +385,8 @@ exec_file_attach (char *filename, int from_tty) /* Tell display code (if any) about the changed file name. */ if (deprecated_exec_file_display_hook) (*deprecated_exec_file_display_hook) (filename); - - do_cleanups (cleanups); } + bfd_cache_close_all (); observer_notify_executable_changed (); } @@ -278,7 +402,6 @@ exec_file_attach (char *filename, int from_tty) static void exec_file_command (char *args, int from_tty) { - char **argv; char *filename; if (from_tty && target_has_execution @@ -288,13 +411,11 @@ exec_file_command (char *args, int from_tty) if (args) { - struct cleanup *cleanups; - /* Scan through the args and pick up the first non option arg as the filename. */ - argv = gdb_buildargv (args); - cleanups = make_cleanup_freeargv (argv); + gdb_argv built_argv (args); + char **argv = built_argv.get (); for (; (*argv != NULL) && (**argv == '-'); argv++) {; @@ -302,11 +423,8 @@ exec_file_command (char *args, int from_tty) if (*argv == NULL) error (_("No executable file name was specified")); - filename = tilde_expand (*argv); - make_cleanup (xfree, filename); - exec_file_attach (filename, from_tty); - - do_cleanups (cleanups); + gdb::unique_xmalloc_ptr filename (tilde_expand (*argv)); + exec_file_attach (filename.get (), from_tty); } else exec_file_attach (NULL, from_tty); @@ -357,27 +475,38 @@ add_to_section_table (bfd *abfd, struct bfd_section *asect, (*table_pp)++; } -int -resize_section_table (struct target_section_table *table, int num_added) +/* 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 = num_added + old_count; + new_count = adjustment + old_count; if (new_count) { - table->sections = xrealloc (table->sections, - sizeof (struct target_section) * new_count); + table->sections = XRESIZEVEC (struct target_section, table->sections, + new_count); table->sections_end = table->sections + new_count; } else - { - xfree (table->sections); - table->sections = table->sections_end = NULL; - } + clear_section_table (table); return old_count; } @@ -394,7 +523,7 @@ build_section_table (struct bfd *some_bfd, struct target_section **start, count = bfd_count_sections (some_bfd); if (*start) xfree (* start); - *start = (struct target_section *) xmalloc (count * sizeof (**start)); + *start = XNEWVEC (struct target_section, count); *end = *start; bfd_map_over_sections (some_bfd, add_to_section_table, (char *) end); if (*end > *start + count) @@ -430,11 +559,8 @@ add_target_sections (void *owner, /* If these are the first file sections we can provide memory from, push the file_stratum target. */ - if (!using_exec_ops) - { - using_exec_ops = 1; - push_target (&exec_ops); - } + if (!target_is_pushed (&exec_ops)) + push_target (&exec_ops); } } @@ -529,7 +655,59 @@ remove_target_sections (void *owner) -VEC(mem_range_s) * +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_get_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; +} + +/* Appends 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. Returns the augmented + VEC. */ + +static VEC(mem_range_s) * section_table_available_memory (VEC(mem_range_s) *memory, CORE_ADDR memaddr, ULONGEST len, struct target_section *sections, @@ -558,17 +736,72 @@ section_table_available_memory (VEC(mem_range_s) *memory, r = VEC_safe_push (mem_range_s, memory, NULL); - r->start = max (lo1, lo2); - r->length = min (hi1, hi2) - r->start; + r->start = std::max (lo1, lo2); + r->length = std::min (hi1, hi2) - r->start; } } return memory; } -int +enum target_xfer_status +section_table_read_available_memory (gdb_byte *readbuf, ULONGEST offset, + ULONGEST len, ULONGEST *xfered_len) +{ + VEC(mem_range_s) *available_memory = NULL; + struct target_section_table *table; + struct cleanup *old_chain; + mem_range_s *r; + int i; + + table = target_get_section_table (&exec_ops); + available_memory = section_table_available_memory (available_memory, + offset, len, + table->sections, + table->sections_end); + + old_chain = make_cleanup (VEC_cleanup(mem_range_s), + &available_memory); + + normalize_mem_ranges (available_memory); + + for (i = 0; + VEC_iterate (mem_range_s, available_memory, i, r); + i++) + { + 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 (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; + } + do_cleanups (old_chain); + return status; + } + } + do_cleanups (old_chain); + + *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, const char *section_name) @@ -602,7 +835,14 @@ section_table_xfer_memory_partial (gdb_byte *readbuf, const gdb_byte *writebuf, res = bfd_get_section_contents (abfd, asect, readbuf, memaddr - p->addr, len); - return (res != 0) ? len : 0; + + if (res != 0) + { + *xfered_len = len; + return TARGET_XFER_OK; + } + else + return TARGET_XFER_EOF; } else if (memaddr >= p->endaddr) { @@ -621,12 +861,18 @@ section_table_xfer_memory_partial (gdb_byte *readbuf, const gdb_byte *writebuf, res = bfd_get_section_contents (abfd, asect, readbuf, memaddr - p->addr, len); - return (res != 0) ? len : 0; + if (res != 0) + { + *xfered_len = len; + return TARGET_XFER_OK; + } + else + return TARGET_XFER_EOF; } } } - return 0; /* We can't help. */ + return TARGET_XFER_EOF; /* We can't help. */ } static struct target_section_table * @@ -635,22 +881,22 @@ exec_get_section_table (struct target_ops *ops) return current_target_sections; } -static LONGEST +static enum target_xfer_status exec_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 offset, ULONGEST len, ULONGEST *xfered_len) { struct target_section_table *table = target_get_section_table (ops); if (object == TARGET_OBJECT_MEMORY) return section_table_xfer_memory_partial (readbuf, writebuf, - offset, len, + offset, len, xfered_len, table->sections, table->sections_end, NULL); else - return -1; + return TARGET_XFER_E_IO; } @@ -801,7 +1047,18 @@ exec_set_section_address (const char *filename, int index, CORE_ADDR address) breakpoint_init_inferior). */ static int -ignore (struct gdbarch *gdbarch, struct bp_target_info *bp_tgt) +ignore (struct target_ops *ops, struct gdbarch *gdbarch, + struct bp_target_info *bp_tgt) +{ + return 0; +} + +/* Implement the to_remove_breakpoint method. */ + +static int +exec_remove_breakpoint (struct target_ops *ops, struct gdbarch *gdbarch, + struct bp_target_info *bp_tgt, + enum remove_bp_reason reason) { return 0; } @@ -815,16 +1072,12 @@ exec_has_memory (struct target_ops *ops) != current_target_sections->sections_end); } -/* Find mapped memory. */ - -extern void -exec_set_find_memory_regions (int (*func) (find_memory_region_ftype, void *)) +static char * +exec_make_note_section (struct target_ops *self, bfd *obfd, int *note_size) { - exec_ops.to_find_memory_regions = func; + error (_("Can't create a corefile")); } -static char *exec_make_note_section (bfd *, int *); - /* Fill in the exec file target vector. Very few entries need to be defined. */ @@ -837,16 +1090,15 @@ init_exec_ops (void) Specify the filename of the executable file."; exec_ops.to_open = exec_open; exec_ops.to_close = exec_close_1; - exec_ops.to_attach = find_default_attach; exec_ops.to_xfer_partial = exec_xfer_partial; exec_ops.to_get_section_table = exec_get_section_table; exec_ops.to_files_info = exec_files_info; exec_ops.to_insert_breakpoint = ignore; - exec_ops.to_remove_breakpoint = ignore; - exec_ops.to_create_inferior = find_default_create_inferior; + exec_ops.to_remove_breakpoint = exec_remove_breakpoint; exec_ops.to_stratum = file_stratum; exec_ops.to_has_memory = exec_has_memory; exec_ops.to_make_corefile_notes = exec_make_note_section; + exec_ops.to_find_memory_regions = objfile_find_memory_regions; exec_ops.to_magic = OPS_MAGIC; } @@ -892,9 +1144,3 @@ Show writing into executable and core files."), NULL, add_target_with_completer (&exec_ops, filename_completer); } - -static char * -exec_make_note_section (bfd *obfd, int *note_size) -{ - error (_("Can't create a corefile")); -}