diff options
Diffstat (limited to 'gdb/record.c')
-rw-r--r-- | gdb/record.c | 566 |
1 files changed, 547 insertions, 19 deletions
diff --git a/gdb/record.c b/gdb/record.c index 608673a..2ff33d6 100644 --- a/gdb/record.c +++ b/gdb/record.c @@ -23,10 +23,15 @@ #include "gdbthread.h" #include "event-top.h" #include "exceptions.h" +#include "completer.h" +#include "arch-utils.h" #include "gdbcore.h" #include "exec.h" #include "record.h" +#include "elf-bfd.h" +#include "gcore.h" +#include <byteswap.h> #include <signal.h> /* This module implements "target record", also known as "process @@ -54,6 +59,8 @@ #define RECORD_IS_REPLAY \ (record_list->next || execution_direction == EXEC_REVERSE) +#define RECORD_FILE_MAGIC netorder32(0x20091016) + /* These are the core structs of the process record functionality. A record_entry is a record of the value change of a register @@ -545,24 +552,24 @@ record_check_insn_num (int set_terminal) if (q) record_stop_at_limit = 0; else - error (_("Process record: inferior program stopped.")); + error (_("Process record: stopped by user.")); } } } } +static void +record_arch_list_cleanups (void *ignore) +{ + record_list_release (record_arch_list_tail); +} + /* Before inferior step (when GDB record the running message, inferior only can step), GDB will call this function to record the values to record_list. This function will call gdbarch_process_record to record the running message of inferior and set them to record_arch_list, and add it to record_list. */ -static void -record_message_cleanups (void *ignore) -{ - record_list_release (record_arch_list_tail); -} - struct record_message_args { struct regcache *regcache; enum target_signal signal; @@ -574,7 +581,7 @@ record_message (void *args) int ret; struct record_message_args *myargs = args; struct gdbarch *gdbarch = get_regcache_arch (myargs->regcache); - struct cleanup *old_cleanups = make_cleanup (record_message_cleanups, 0); + struct cleanup *old_cleanups = make_cleanup (record_arch_list_cleanups, 0); record_arch_list_head = NULL; record_arch_list_tail = NULL; @@ -714,8 +721,8 @@ record_exec_insn (struct regcache *regcache, struct gdbarch *gdbarch, { entry->u.mem.mem_entry_not_accessible = 1; if (record_debug) - warning (_("Process record: error reading memory at " - "addr = %s len = %d."), + warning ("Process record: error reading memory at " + "addr = %s len = %d.", paddress (gdbarch, entry->u.mem.addr), entry->u.mem.len); } @@ -727,8 +734,8 @@ record_exec_insn (struct regcache *regcache, struct gdbarch *gdbarch, { entry->u.mem.mem_entry_not_accessible = 1; if (record_debug) - warning (_("Process record: error writing memory at " - "addr = %s len = %d."), + warning ("Process record: error writing memory at " + "addr = %s len = %d.", paddress (gdbarch, entry->u.mem.addr), entry->u.mem.len); } @@ -765,6 +772,8 @@ static int (*tmp_to_insert_breakpoint) (struct gdbarch *, static int (*tmp_to_remove_breakpoint) (struct gdbarch *, struct bp_target_info *); +static void record_restore (void); + /* Open the process record target. */ static void @@ -791,6 +800,7 @@ record_core_open_1 (char *name, int from_tty) } push_target (&record_core_ops); + record_restore (); } /* "to_open" target method for 'live' processes. */ @@ -1438,8 +1448,8 @@ record_xfer_partial (struct target_ops *ops, enum target_object object, record_list_release (record_arch_list_tail); if (record_debug) fprintf_unfiltered (gdb_stdlog, - _("Process record: failed to record " - "execution log.")); + "Process record: failed to record " + "execution log."); return -1; } if (record_arch_list_add_end ()) @@ -1447,8 +1457,8 @@ record_xfer_partial (struct target_ops *ops, enum target_object object, record_list_release (record_arch_list_tail); if (record_debug) fprintf_unfiltered (gdb_stdlog, - _("Process record: failed to record " - "execution log.")); + "Process record: failed to record " + "execution log."); return -1; } record_list->next = record_arch_list_head; @@ -1885,9 +1895,513 @@ info_record_command (char *args, int from_tty) record_insn_max_num); } +/* Record log save-file format + Version 1 (never released) + + Header: + 4 bytes: magic number htonl(0x20090829). + NOTE: be sure to change whenever this file format changes! + + Records: + record_end: + 1 byte: record type (record_end, see enum record_type). + record_reg: + 1 byte: record type (record_reg, see enum record_type). + 8 bytes: register id (network byte order). + MAX_REGISTER_SIZE bytes: register value. + record_mem: + 1 byte: record type (record_mem, see enum record_type). + 8 bytes: memory length (network byte order). + 8 bytes: memory address (network byte order). + n bytes: memory value (n == memory length). + + Version 2 + 4 bytes: magic number netorder32(0x20091016). + NOTE: be sure to change whenever this file format changes! + + Records: + record_end: + 1 byte: record type (record_end, see enum record_type). + 4 bytes: signal + 4 bytes: instruction count + record_reg: + 1 byte: record type (record_reg, see enum record_type). + 4 bytes: register id (network byte order). + n bytes: register value (n == actual register size). + (eg. 4 bytes for x86 general registers). + record_mem: + 1 byte: record type (record_mem, see enum record_type). + 4 bytes: memory length (network byte order). + 8 bytes: memory address (network byte order). + n bytes: memory value (n == memory length). + +*/ + +/* bfdcore_read -- read bytes from a core file section. */ + +static inline void +bfdcore_read (bfd *obfd, asection *osec, void *buf, int len, int *offset) +{ + int ret = bfd_get_section_contents (obfd, osec, buf, *offset, len); + + if (ret) + *offset += len; + else + error (_("Failed to read %d bytes from core file %s ('%s').\n"), + len, bfd_get_filename (obfd), + bfd_errmsg (bfd_get_error ())); +} + +static inline uint64_t +netorder64 (uint64_t fromfile) +{ + return (BYTE_ORDER == LITTLE_ENDIAN) + ? bswap_64 (fromfile) + : fromfile; +} + +static inline uint32_t +netorder32 (uint32_t fromfile) +{ + return (BYTE_ORDER == LITTLE_ENDIAN) + ? bswap_32 (fromfile) + : fromfile; +} + +static inline uint16_t +netorder16 (uint16_t fromfile) +{ + return (BYTE_ORDER == LITTLE_ENDIAN) + ? bswap_16 (fromfile) + : fromfile; +} + +/* Restore the execution log from a core_bfd file. */ +static void +record_restore (void) +{ + uint32_t magic; + struct cleanup *old_cleanups; + struct record_entry *rec; + asection *osec; + uint32_t osec_size; + int bfd_offset = 0; + struct regcache *regcache; + + /* We restore the execution log from the open core bfd, + if there is one. */ + if (core_bfd == NULL) + return; + + /* "record_restore" can only be called when record list is empty. */ + gdb_assert (record_first.next == NULL); + + if (record_debug) + printf_filtered ("Restoring recording from core file.\n"); + + /* Now need to find our special note section. */ + osec = bfd_get_section_by_name (core_bfd, "null0"); + osec_size = bfd_section_size (core_bfd, osec); + if (record_debug) + printf_filtered ("Find precord section %s.\n", + osec ? "succeeded" : "failed"); + if (!osec) + return; + if (record_debug) + printf_filtered ("%s", bfd_section_name (core_bfd, osec)); + + /* Check the magic code. */ + bfdcore_read (core_bfd, osec, &magic, sizeof (magic), &bfd_offset); + if (magic != RECORD_FILE_MAGIC) + error (_("Version mis-match or file format error in core file %s."), + bfd_get_filename (core_bfd)); + if (record_debug) + printf_filtered ("\ + Reading 4-byte magic cookie RECORD_FILE_MAGIC (0x%08x)\n", + netorder32 (magic)); + + /* Restore the entries in recfd into record_arch_list_head and + record_arch_list_tail. */ + record_arch_list_head = NULL; + record_arch_list_tail = NULL; + record_insn_num = 0; + old_cleanups = make_cleanup (record_arch_list_cleanups, 0); + regcache = get_current_regcache (); + + while (1) + { + int ret; + uint8_t tmpu8; + uint32_t regnum, len, signal, count; + uint64_t addr; + + /* We are finished when offset reaches osec_size. */ + if (bfd_offset >= osec_size) + break; + bfdcore_read (core_bfd, osec, &tmpu8, sizeof (tmpu8), &bfd_offset); + + switch (tmpu8) + { + case record_reg: /* reg */ + /* Get register number to regnum. */ + bfdcore_read (core_bfd, osec, ®num, + sizeof (regnum), &bfd_offset); + regnum = netorder32 (regnum); + + rec = record_reg_alloc (regcache, regnum); + + /* Get val. */ + bfdcore_read (core_bfd, osec, record_get_loc (rec), + rec->u.reg.len, &bfd_offset); + + if (record_debug) + printf_filtered ("\ + Reading register %d (1 plus %d plus %d bytes)\n", + rec->u.reg.num, + sizeof (regnum), + rec->u.reg.len); + break; + + case record_mem: /* mem */ + /* Get len. */ + bfdcore_read (core_bfd, osec, &len, + sizeof (len), &bfd_offset); + len = netorder32 (len); + + /* Get addr. */ + bfdcore_read (core_bfd, osec, &addr, + sizeof (addr), &bfd_offset); + addr = netorder64 (addr); + + rec = record_mem_alloc (addr, len); + + /* Get val. */ + bfdcore_read (core_bfd, osec, record_get_loc (rec), + rec->u.mem.len, &bfd_offset); + + if (record_debug) + printf_filtered ("\ + Reading memory %s (1 plus %d plus %d plus %d bytes)\n", + paddress (get_current_arch (), + rec->u.mem.addr), + sizeof (addr), + sizeof (len), + rec->u.mem.len); + break; + + case record_end: /* end */ + rec = record_end_alloc (); + record_insn_num ++; + + /* Get signal value. */ + bfdcore_read (core_bfd, osec, &signal, + sizeof (signal), &bfd_offset); + signal = netorder32 (signal); + rec->u.end.sigval = signal; + + /* Get insn count. */ + bfdcore_read (core_bfd, osec, &count, + sizeof (count), &bfd_offset); + count = netorder32 (count); + rec->u.end.insn_num = count; + record_insn_count = count + 1; + if (record_debug) + printf_filtered ("\ + Reading record_end (1 + %d + %d bytes), offset == %s\n", + sizeof (signal), + sizeof (count), + paddress (get_current_arch (), + bfd_offset)); + break; + + default: + error (_("Bad entry type in core file %s."), + bfd_get_filename (core_bfd)); + break; + } + + /* Add rec to record arch list. */ + record_arch_list_add (rec); + } + + discard_cleanups (old_cleanups); + + /* Add record_arch_list_head to the end of record list. */ + record_first.next = record_arch_list_head; + record_arch_list_head->prev = &record_first; + record_arch_list_tail->next = NULL; + record_list = &record_first; + + /* Update record_insn_max_num. */ + if (record_insn_num > record_insn_max_num) + { + record_insn_max_num = record_insn_num; + warning (_("Auto increase record/replay buffer limit to %d."), + record_insn_max_num); + } + + /* Succeeded. */ + printf_filtered (_("Restored records from core file %s.\n"), + bfd_get_filename (core_bfd)); + + print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC); +} + +/* bfdcore_write -- write bytes into a core file section. */ + +static inline void +bfdcore_write (bfd *obfd, asection *osec, void *buf, int len, int *offset) +{ + int ret = bfd_set_section_contents (obfd, osec, buf, *offset, len); + + if (ret) + *offset += len; + else + error (_("Failed to write %d bytes to core file %s ('%s').\n"), + len, bfd_get_filename (obfd), + bfd_errmsg (bfd_get_error ())); +} + +/* Restore the execution log from a file. We use a modified elf + corefile format, with an extra section for our data. */ + +static void +cmd_record_restore (char *args, int from_tty) +{ + core_file_command (args, from_tty); + record_open (args, from_tty); +} + +static void +record_save_cleanups (void *data) +{ + bfd *obfd = data; + char *pathname = xstrdup (bfd_get_filename (obfd)); + bfd_close (obfd); + unlink (pathname); + xfree (pathname); +} + +/* Save the execution log to a file. We use a modified elf corefile + format, with an extra section for our data. */ + +static void +cmd_record_save (char *args, int from_tty) +{ + char *recfilename, recfilename_buffer[40]; + int recfd; + struct record_entry *cur_record_list; + uint32_t magic; + struct regcache *regcache; + struct gdbarch *gdbarch; + struct cleanup *old_cleanups; + struct cleanup *set_cleanups; + bfd *obfd; + int save_size = 0; + asection *osec = NULL; + int bfd_offset = 0; + + if (strcmp (current_target.to_shortname, "record") != 0) + error (_("This command can only be used with target 'record'.\n" + "Use 'target record' first.\n")); + + if (args && *args) + recfilename = args; + else + { + /* Default recfile name is "gdb_record.PID". */ + snprintf (recfilename_buffer, sizeof (recfilename_buffer), + "gdb_record.%d", PIDGET (inferior_ptid)); + recfilename = recfilename_buffer; + } + + /* Open the save file. */ + if (record_debug) + printf_filtered ("Saving execution log to core file '%s'\n", recfilename); + + /* Open the output file. */ + obfd = create_gcore_bfd (recfilename); + old_cleanups = make_cleanup (record_save_cleanups, obfd); + + /* Save the current record entry to "cur_record_list". */ + cur_record_list = record_list; + + /* Get the values of regcache and gdbarch. */ + regcache = get_current_regcache (); + gdbarch = get_regcache_arch (regcache); + + /* Disable the GDB operation record. */ + set_cleanups = record_gdb_operation_disable_set (); + + /* Reverse execute to the begin of record list. */ + while (1) + { + /* Check for beginning and end of log. */ + if (record_list == &record_first) + break; + + record_exec_insn (regcache, gdbarch, record_list); + + if (record_list->prev) + record_list = record_list->prev; + } + + /* Compute the size needed for the extra bfd section. */ + save_size = 4; /* magic cookie */ + for (record_list = record_first.next; record_list; + record_list = record_list->next) + switch (record_list->type) + { + case record_end: + save_size += 1 + 4 + 4; + break; + case record_reg: + save_size += 1 + 4 + record_list->u.reg.len; + break; + case record_mem: + save_size += 1 + 4 + 8 + record_list->u.mem.len; + break; + } + + /* Make the new bfd section. */ + osec = bfd_make_section_anyway_with_flags (obfd, "precord", + SEC_HAS_CONTENTS + | SEC_READONLY); + if (osec == NULL) + error (_("Failed to create 'precord' section for corefile %s: %s"), + recfilename, + bfd_errmsg (bfd_get_error ())); + bfd_set_section_size (obfd, osec, save_size); + bfd_set_section_vma (obfd, osec, 0); + bfd_set_section_alignment (obfd, osec, 0); + bfd_section_lma (obfd, osec) = 0; + + /* Save corefile state. */ + write_gcore_file (obfd); + + /* Write out the record log. */ + /* Write the magic code. */ + magic = RECORD_FILE_MAGIC; + if (record_debug) + printf_filtered ("\ + Writing 4-byte magic cookie RECORD_FILE_MAGIC (0x%08x)\n", + magic); + bfdcore_write (obfd, osec, &magic, sizeof (magic), &bfd_offset); + + /* Save the entries to recfd and forward execute to the end of + record list. */ + record_list = &record_first; + while (1) + { + /* Save entry. */ + if (record_list != &record_first) + { + uint8_t type; + uint32_t regnum, len, signal, count; + uint64_t addr; + + type = record_list->type; + bfdcore_write (obfd, osec, &type, sizeof (type), &bfd_offset); + + switch (record_list->type) + { + case record_reg: /* reg */ + if (record_debug) + printf_filtered ("\ + Writing register %d (1 plus %d plus %d bytes)\n", + record_list->u.reg.num, + sizeof (regnum), + record_list->u.reg.len); + + /* Write regnum. */ + regnum = netorder32 (record_list->u.reg.num); + bfdcore_write (obfd, osec, ®num, + sizeof (regnum), &bfd_offset); + + /* Write regval. */ + bfdcore_write (obfd, osec, record_get_loc (record_list), + record_list->u.reg.len, &bfd_offset); + break; + + case record_mem: /* mem */ + if (record_debug) + printf_filtered ("\ + Writing memory %s (1 plus %d plus %d plus %d bytes)\n", + paddress (gdbarch, + record_list->u.mem.addr), + sizeof (addr), + sizeof (len), + record_list->u.mem.len); + + /* Write memlen. */ + len = netorder32 (record_list->u.mem.len); + bfdcore_write (obfd, osec, &len, sizeof (len), &bfd_offset); + + /* Write memaddr. */ + addr = netorder64 (record_list->u.mem.addr); + bfdcore_write (obfd, osec, &addr, + sizeof (addr), &bfd_offset); + + /* Write memval. */ + bfdcore_write (obfd, osec, record_get_loc (record_list), + record_list->u.mem.len, &bfd_offset); + break; + + case record_end: + if (record_debug) + printf_filtered ("\ + Writing record_end (1 + %d + %d bytes)\n", + sizeof (signal), + sizeof (count)); + /* Write signal value. */ + signal = netorder32 (record_list->u.end.sigval); + bfdcore_write (obfd, osec, &signal, + sizeof (signal), &bfd_offset); + + /* Write insn count. */ + count = netorder32 (record_list->u.end.insn_num); + bfdcore_write (obfd, osec, &count, + sizeof (count), &bfd_offset); + break; + } + } + + /* Execute entry. */ + record_exec_insn (regcache, gdbarch, record_list); + + if (record_list->next) + record_list = record_list->next; + else + break; + } + + /* Reverse execute to cur_record_list. */ + while (1) + { + /* Check for beginning and end of log. */ + if (record_list == cur_record_list) + break; + + record_exec_insn (regcache, gdbarch, record_list); + + if (record_list->prev) + record_list = record_list->prev; + } + + do_cleanups (set_cleanups); + bfd_close (obfd); + discard_cleanups (old_cleanups); + + /* Succeeded. */ + printf_filtered (_("Saved core file %s with execution log.\n"), + recfilename); +} + void _initialize_record (void) { + struct cmd_list_element *c; + /* Init record_first. */ record_first.prev = NULL; record_first.next = NULL; @@ -1906,9 +2420,11 @@ _initialize_record (void) NULL, show_record_debug, &setdebuglist, &showdebuglist); - add_prefix_cmd ("record", class_obscure, cmd_record_start, - _("Abbreviated form of \"target record\" command."), - &record_cmdlist, "record ", 0, &cmdlist); + c = add_prefix_cmd ("record", class_obscure, cmd_record_start, + _("Abbreviated form of \"target record\" command."), + &record_cmdlist, "record ", 0, &cmdlist); + set_cmd_completer (c, filename_completer); + add_com_alias ("rec", "record", class_obscure, 1); add_prefix_cmd ("record", class_support, set_record_command, _("Set record options"), &set_record_cmdlist, @@ -1923,6 +2439,18 @@ _initialize_record (void) "info record ", 0, &infolist); add_alias_cmd ("rec", "record", class_obscure, 1, &infolist); + c = add_cmd ("save", class_obscure, cmd_record_save, + _("Save the execution log to a file.\n\ +Argument is optional filename.\n\ +Default filename is 'gdb_record.<process_id>'."), + &record_cmdlist); + set_cmd_completer (c, filename_completer); + + c = add_cmd ("restore", class_obscure, cmd_record_restore, + _("Restore the execution log from a file.\n\ +Argument is filename. File must be created with 'record save'."), + &record_cmdlist); + set_cmd_completer (c, filename_completer); add_cmd ("delete", class_obscure, cmd_record_delete, _("Delete the rest of execution log and start recording it anew."), |