diff options
Diffstat (limited to 'src/src/stack.c')
| -rw-r--r-- | src/src/stack.c | 760 |
1 files changed, 760 insertions, 0 deletions
diff --git a/src/src/stack.c b/src/src/stack.c new file mode 100644 index 00000000..c277dfd0 --- /dev/null +++ b/src/src/stack.c @@ -0,0 +1,760 @@ +/* Unwinding of frames like gstack/pstack. + Copyright (C) 2013-2014 Red Hat, Inc. + This file is part of elfutils. + + This file 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. + + elfutils 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 <config.h> +#include <assert.h> +#include <argp.h> +#include <error.h> +#include <stdlib.h> +#include <inttypes.h> +#include <stdio.h> +#include <stdio_ext.h> +#include <string.h> +#include <locale.h> +#include <fcntl.h> +#include ELFUTILS_HEADER(dwfl) + +#include <dwarf.h> +#include <system.h> + +/* Name and version of program. */ +static void print_version (FILE *stream, struct argp_state *state); +ARGP_PROGRAM_VERSION_HOOK_DEF = print_version; + +/* Bug report address. */ +ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT; + +/* non-printable argp options. */ +#define OPT_DEBUGINFO 0x100 +#define OPT_COREFILE 0x101 + +static bool show_activation = false; +static bool show_module = false; +static bool show_build_id = false; +static bool show_source = false; +static bool show_one_tid = false; +static bool show_quiet = false; +static bool show_raw = false; +static bool show_modules = false; +static bool show_debugname = false; +static bool show_inlines = false; + +static int maxframes = 256; + +struct frame +{ + Dwarf_Addr pc; + bool isactivation; +}; + +struct frames +{ + int frames; + int allocated; + struct frame *frame; +}; + +static Dwfl *dwfl = NULL; +static pid_t pid = 0; +static int core_fd = -1; +static Elf *core = NULL; +static const char *exec = NULL; +static char *debuginfo_path = NULL; + +static const Dwfl_Callbacks proc_callbacks = + { + .find_elf = dwfl_linux_proc_find_elf, + .find_debuginfo = dwfl_standard_find_debuginfo, + .debuginfo_path = &debuginfo_path, + }; + +static const Dwfl_Callbacks core_callbacks = + { + .find_elf = dwfl_build_id_find_elf, + .find_debuginfo = dwfl_standard_find_debuginfo, + .debuginfo_path = &debuginfo_path, + }; + +#ifdef USE_DEMANGLE +static size_t demangle_buffer_len = 0; +static char *demangle_buffer = NULL; +#endif + +/* Whether any frames have been shown at all. Determines exit status. */ +static bool frames_shown = false; + +/* Program exit codes. All frames shown without any errors is GOOD. + Some frames shown with some non-fatal errors is an ERROR. A fatal + error or no frames shown at all is BAD. A command line USAGE exit + is generated by argp_error. */ +#define EXIT_OK 0 +#define EXIT_ERROR 1 +#define EXIT_BAD 2 +#define EXIT_USAGE 64 + +static int +get_addr_width (Dwfl_Module *mod) +{ + // Try to find the address wide if possible. + static int width = 0; + if (width == 0 && mod) + { + Dwarf_Addr bias; + Elf *elf = dwfl_module_getelf (mod, &bias); + if (elf) + { + GElf_Ehdr ehdr_mem; + GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem); + if (ehdr) + width = ehdr->e_ident[EI_CLASS] == ELFCLASS32 ? 8 : 16; + } + } + if (width == 0) + width = 16; + + return width; +} + +static int +module_callback (Dwfl_Module *mod, void **userdata __attribute__((unused)), + const char *name, Dwarf_Addr start, + void *arg __attribute__((unused))) +{ + /* Forces resolving of main elf and debug files. */ + Dwarf_Addr bias; + Elf *elf = dwfl_module_getelf (mod, &bias); + Dwarf *dwarf = dwfl_module_getdwarf (mod, &bias); + + Dwarf_Addr end; + const char *mainfile; + const char *debugfile; + const char *modname = dwfl_module_info (mod, NULL, NULL, &end, NULL, + NULL, &mainfile, &debugfile); + assert (strcmp (modname, name) == 0); + + int width = get_addr_width (mod); + printf ("0x%0*" PRIx64 "-0x%0*" PRIx64 " %s\n", + width, start, width, end, basename (name)); + + const unsigned char *id; + GElf_Addr id_vaddr; + int id_len = dwfl_module_build_id (mod, &id, &id_vaddr); + if (id_len > 0) + { + printf (" ["); + do + printf ("%02" PRIx8, *id++); + while (--id_len > 0); + printf ("]\n"); + } + + if (elf != NULL) + printf (" %s\n", mainfile != NULL ? mainfile : "-"); + if (dwarf != NULL) + printf (" %s\n", debugfile != NULL ? debugfile : "-"); + + return DWARF_CB_OK; +} + +static int +frame_callback (Dwfl_Frame *state, void *arg) +{ + struct frames *frames = (struct frames *) arg; + int nr = frames->frames; + if (! dwfl_frame_pc (state, &frames->frame[nr].pc, + &frames->frame[nr].isactivation)) + return -1; + + frames->frames++; + if (frames->frames == maxframes) + return DWARF_CB_ABORT; + + if (frames->frames == frames->allocated) + { + frames->allocated *= 2; + frames->frame = realloc (frames->frame, + sizeof (struct frame) * frames->allocated); + if (frames->frame == NULL) + error (EXIT_BAD, errno, "realloc frames.frame"); + } + + return DWARF_CB_OK; +} + +static const char* +die_name (Dwarf_Die *die) +{ + Dwarf_Attribute attr; + const char *name; + name = dwarf_formstring (dwarf_attr_integrate (die, + DW_AT_MIPS_linkage_name, + &attr) + ?: dwarf_attr_integrate (die, + DW_AT_linkage_name, + &attr)); + if (name == NULL) + name = dwarf_diename (die); + + return name; +} + +static void +print_frame (int nr, Dwarf_Addr pc, bool isactivation, + Dwarf_Addr pc_adjusted, Dwfl_Module *mod, + const char *symname, Dwarf_Die *cudie, + Dwarf_Die *die) +{ + int width = get_addr_width (mod); + printf ("#%-2u 0x%0*" PRIx64, nr, width, (uint64_t) pc); + + if (show_activation) + printf ("%4s", ! isactivation ? "- 1" : ""); + + if (symname != NULL) + { +#ifdef USE_DEMANGLE + // Require GNU v3 ABI by the "_Z" prefix. + if (! show_raw && symname[0] == '_' && symname[1] == 'Z') + { + int status = -1; + char *dsymname = __cxa_demangle (symname, demangle_buffer, + &demangle_buffer_len, &status); + if (status == 0) + symname = demangle_buffer = dsymname; + } +#endif + printf (" %s", symname); + } + + const char* fname; + Dwarf_Addr start; + fname = dwfl_module_info(mod, NULL, &start, + NULL, NULL, NULL, NULL, NULL); + if (show_module) + { + if (fname != NULL) + printf (" - %s", fname); + } + + if (show_build_id) + { + const unsigned char *id; + GElf_Addr id_vaddr; + int id_len = dwfl_module_build_id (mod, &id, &id_vaddr); + if (id_len > 0) + { + printf ("\n ["); + do + printf ("%02" PRIx8, *id++); + while (--id_len > 0); + printf ("]@0x%0" PRIx64 "+0x%" PRIx64, + start, pc_adjusted - start); + } + } + + if (show_source) + { + int line, col; + const char* sname; + line = col = -1; + sname = NULL; + if (die != NULL) + { + Dwarf_Files *files; + if (dwarf_getsrcfiles (cudie, &files, NULL) == 0) + { + Dwarf_Attribute attr; + Dwarf_Word val; + if (dwarf_formudata (dwarf_attr (die, DW_AT_call_file, &attr), + &val) == 0) + { + sname = dwarf_filesrc (files, val, NULL, NULL); + if (dwarf_formudata (dwarf_attr (die, DW_AT_call_line, + &attr), &val) == 0) + { + line = val; + if (dwarf_formudata (dwarf_attr (die, DW_AT_call_column, + &attr), &val) == 0) + col = val; + } + } + } + } + else + { + Dwfl_Line *lineobj = dwfl_module_getsrc(mod, pc_adjusted); + if (lineobj) + sname = dwfl_lineinfo (lineobj, NULL, &line, &col, NULL, NULL); + } + + if (sname != NULL) + { + printf ("\n %s", sname); + if (line > 0) + { + printf (":%d", line); + if (col > 0) + printf (":%d", col); + } + } + } + printf ("\n"); +} + +static void +print_inline_frames (int *nr, Dwarf_Addr pc, bool isactivation, + Dwarf_Addr pc_adjusted, Dwfl_Module *mod, + const char *symname, Dwarf_Die *cudie, Dwarf_Die *die) +{ + Dwarf_Die *scopes = NULL; + int nscopes = dwarf_getscopes_die (die, &scopes); + if (nscopes > 0) + { + /* scopes[0] == die, the lowest level, for which we already have + the name. This is the actual source location where it + happened. */ + print_frame ((*nr)++, pc, isactivation, pc_adjusted, mod, symname, + NULL, NULL); + + /* last_scope is the source location where the next frame/function + call was done. */ + Dwarf_Die *last_scope = &scopes[0]; + for (int i = 1; i < nscopes && (maxframes == 0 || *nr < maxframes); i++) + { + Dwarf_Die *scope = &scopes[i]; + int tag = dwarf_tag (scope); + if (tag != DW_TAG_inlined_subroutine + && tag != DW_TAG_entry_point + && tag != DW_TAG_subprogram) + continue; + + symname = die_name (scope); + print_frame ((*nr)++, pc, isactivation, pc_adjusted, mod, symname, + cudie, last_scope); + + /* Found the "top-level" in which everything was inlined? */ + if (tag == DW_TAG_subprogram) + break; + + last_scope = scope; + } + } + free (scopes); +} + +static void +print_frames (struct frames *frames, pid_t tid, int dwflerr, const char *what) +{ + if (frames->frames > 0) + frames_shown = true; + + printf ("TID %d:\n", tid); + int frame_nr = 0; + for (int nr = 0; nr < frames->frames && (maxframes == 0 + || frame_nr < maxframes); nr++) + { + Dwarf_Addr pc = frames->frame[nr].pc; + bool isactivation = frames->frame[nr].isactivation; + Dwarf_Addr pc_adjusted = pc - (isactivation ? 0 : 1); + + /* Get PC->SYMNAME. */ + Dwfl_Module *mod = dwfl_addrmodule (dwfl, pc_adjusted); + const char *symname = NULL; + Dwarf_Die die_mem; + Dwarf_Die *die = NULL; + Dwarf_Die *cudie = NULL; + if (mod && ! show_quiet) + { + if (show_debugname) + { + Dwarf_Addr bias = 0; + Dwarf_Die *scopes = NULL; + cudie = dwfl_module_addrdie (mod, pc_adjusted, &bias); + int nscopes = dwarf_getscopes (cudie, pc_adjusted - bias, + &scopes); + + /* Find the first function-like DIE with a name in scope. */ + for (int i = 0; symname == NULL && i < nscopes; i++) + { + Dwarf_Die *scope = &scopes[i]; + int tag = dwarf_tag (scope); + if (tag == DW_TAG_subprogram + || tag == DW_TAG_inlined_subroutine + || tag == DW_TAG_entry_point) + symname = die_name (scope); + + if (symname != NULL) + { + die_mem = *scope; + die = &die_mem; + } + } + free (scopes); + } + + if (symname == NULL) + symname = dwfl_module_addrname (mod, pc_adjusted); + } + + if (show_inlines && die != NULL) + print_inline_frames (&frame_nr, pc, isactivation, pc_adjusted, mod, + symname, cudie, die); + else + print_frame (frame_nr++, pc, isactivation, pc_adjusted, mod, symname, + NULL, NULL); + } + + if (frames->frames > 0 && frame_nr == maxframes) + error (0, 0, "tid %d: shown max number of frames " + "(%d, use -n 0 for unlimited)", tid, maxframes); + else if (dwflerr != 0) + { + if (frames->frames > 0) + { + unsigned nr = frames->frames - 1; + Dwarf_Addr pc = frames->frame[nr].pc; + bool isactivation = frames->frame[nr].isactivation; + Dwarf_Addr pc_adjusted = pc - (isactivation ? 0 : 1); + Dwfl_Module *mod = dwfl_addrmodule (dwfl, pc_adjusted); + const char *mainfile = NULL; + const char *modname = dwfl_module_info (mod, NULL, NULL, NULL, NULL, + NULL, &mainfile, NULL); + if (modname == NULL || modname[0] == '\0') + { + if (mainfile != NULL) + modname = mainfile; + else + modname = "<unknown>"; + } + error (0, 0, "%s tid %d at 0x%" PRIx64 " in %s: %s", what, tid, + pc_adjusted, modname, dwfl_errmsg (dwflerr)); + } + else + error (0, 0, "%s tid %d: %s", what, tid, dwfl_errmsg (dwflerr)); + } +} + +static int +thread_callback (Dwfl_Thread *thread, void *thread_arg) +{ + struct frames *frames = (struct frames *) thread_arg; + pid_t tid = dwfl_thread_tid (thread); + int err = 0; + frames->frames = 0; + switch (dwfl_thread_getframes (thread, frame_callback, thread_arg)) + { + case DWARF_CB_OK: + case DWARF_CB_ABORT: + break; + case -1: + err = dwfl_errno (); + break; + default: + abort (); + } + print_frames (frames, tid, err, "dwfl_thread_getframes"); + return DWARF_CB_OK; +} + +static void +print_version (FILE *stream, struct argp_state *state __attribute__ ((unused))) +{ + fprintf (stream, "stack (%s) %s\n", PACKAGE_NAME, PACKAGE_VERSION); +} + +static error_t +parse_opt (int key, char *arg __attribute__ ((unused)), + struct argp_state *state) +{ + switch (key) + { + case 'p': + pid = atoi (arg); + if (pid == 0) + argp_error (state, N_("-p PID should be a positive process id.")); + break; + + case OPT_COREFILE: + core_fd = open (arg, O_RDONLY); + if (core_fd < 0) + error (EXIT_BAD, errno, N_("Cannot open core file '%s'"), arg); + elf_version (EV_CURRENT); + core = elf_begin (core_fd, ELF_C_READ_MMAP, NULL); + if (core == NULL) + error (EXIT_BAD, 0, "core '%s' elf_begin: %s", arg, elf_errmsg(-1)); + break; + + case 'e': + exec = arg; + break; + + case OPT_DEBUGINFO: + debuginfo_path = arg; + break; + + case 'm': + show_module = true; + break; + + case 's': + show_source = true; + break; + + case 'a': + show_activation = true; + break; + + case 'd': + show_debugname = true; + break; + + case 'i': + show_inlines = show_debugname = true; + break; + + case 'v': + show_activation = show_source = show_module = show_debugname = true; + show_inlines = true; + break; + + case 'b': + show_build_id = true; + break; + + case 'q': + show_quiet = true; + break; + + case 'r': + show_raw = true; + break; + + case '1': + show_one_tid = true; + break; + + case 'n': + maxframes = atoi (arg); + if (maxframes < 0) + { + argp_error (state, N_("-n MAXFRAMES should be 0 or higher.")); + return EINVAL; + } + break; + + case 'l': + show_modules = true; + break; + + case ARGP_KEY_END: + if (core == NULL && exec != NULL) + argp_error (state, + N_("-e EXEC needs a core given by --core.")); + + if (pid == 0 && show_one_tid == true) + argp_error (state, + N_("-1 needs a thread id given by -p.")); + + if ((pid == 0 && core == NULL) || (pid != 0 && core != NULL)) + argp_error (state, + N_("One of -p PID or --core COREFILE should be given.")); + + if (pid != 0) + { + dwfl = dwfl_begin (&proc_callbacks); + if (dwfl == NULL) + error (EXIT_BAD, 0, "dwfl_begin: %s", dwfl_errmsg (-1)); + + int err = dwfl_linux_proc_report (dwfl, pid); + if (err < 0) + error (EXIT_BAD, 0, "dwfl_linux_proc_report pid %d: %s", pid, + dwfl_errmsg (-1)); + else if (err > 0) + error (EXIT_BAD, err, "dwfl_linux_proc_report pid %d", pid); + } + + if (core != NULL) + { + dwfl = dwfl_begin (&core_callbacks); + if (dwfl == NULL) + error (EXIT_BAD, 0, "dwfl_begin: %s", dwfl_errmsg (-1)); + if (dwfl_core_file_report (dwfl, core, exec) < 0) + error (EXIT_BAD, 0, "dwfl_core_file_report: %s", dwfl_errmsg (-1)); + } + + if (dwfl_report_end (dwfl, NULL, NULL) != 0) + error (EXIT_BAD, 0, "dwfl_report_end: %s", dwfl_errmsg (-1)); + + if (pid != 0) + { + int err = dwfl_linux_proc_attach (dwfl, pid, false); + if (err < 0) + error (EXIT_BAD, 0, "dwfl_linux_proc_attach pid %d: %s", pid, + dwfl_errmsg (-1)); + else if (err > 0) + error (EXIT_BAD, err, "dwfl_linux_proc_attach pid %d", pid); + } + + if (core != NULL) + { + if (dwfl_core_file_attach (dwfl, core) < 0) + error (EXIT_BAD, 0, "dwfl_core_file_report: %s", dwfl_errmsg (-1)); + } + + /* Makes sure we are properly attached. */ + if (dwfl_pid (dwfl) < 0) + error (EXIT_BAD, 0, "dwfl_pid: %s\n", dwfl_errmsg (-1)); + break; + + default: + return ARGP_ERR_UNKNOWN; + } + return 0; +} + +int +main (int argc, char **argv) +{ + /* We use no threads here which can interfere with handling a stream. */ + __fsetlocking (stdin, FSETLOCKING_BYCALLER); + __fsetlocking (stdout, FSETLOCKING_BYCALLER); + __fsetlocking (stderr, FSETLOCKING_BYCALLER); + + /* Set locale. */ + (void) setlocale (LC_ALL, ""); + + const struct argp_option options[] = + { + { NULL, 0, NULL, 0, N_("Input selection options:"), 0 }, + { "pid", 'p', "PID", 0, + N_("Show stack of process PID"), 0 }, + { "core", OPT_COREFILE, "COREFILE", 0, + N_("Show stack found in COREFILE"), 0 }, + { "executable", 'e', "EXEC", 0, N_("(optional) EXECUTABLE that produced COREFILE"), 0 }, + { "debuginfo-path", OPT_DEBUGINFO, "PATH", 0, + N_("Search path for separate debuginfo files"), 0 }, + + { NULL, 0, NULL, 0, N_("Output selection options:"), 0 }, + { "activation", 'a', NULL, 0, + N_("Additionally show frame activation"), 0 }, + { "debugname", 'd', NULL, 0, + N_("Additionally try to lookup DWARF debuginfo name for frame address"), + 0 }, + { "inlines", 'i', NULL, 0, + N_("Additionally show inlined function frames using DWARF debuginfo if available (implies -d)"), 0 }, + { "module", 'm', NULL, 0, + N_("Additionally show module file information"), 0 }, + { "source", 's', NULL, 0, + N_("Additionally show source file information"), 0 }, + { "verbose", 'v', NULL, 0, + N_("Show all additional information (activation, debugname, inlines, module and source)"), 0 }, + { "quiet", 'q', NULL, 0, + N_("Do not resolve address to function symbol name"), 0 }, + { "raw", 'r', NULL, 0, + N_("Show raw function symbol names, do not try to demangle names"), 0 }, + { "build-id", 'b', NULL, 0, + N_("Show module build-id, load address and pc offset"), 0 }, + { NULL, '1', NULL, 0, + N_("Show the backtrace of only one thread"), 0 }, + { NULL, 'n', "MAXFRAMES", 0, + N_("Show at most MAXFRAMES per thread (default 256, use 0 for unlimited)"), 0 }, + { "list-modules", 'l', NULL, 0, + N_("Show module memory map with build-id, elf and debug files detected"), 0 }, + { NULL, 0, NULL, 0, NULL, 0 } + }; + + const struct argp argp = + { + .options = options, + .parser = parse_opt, + .doc = N_("Print a stack for each thread in a process or core file.\v\ +Program exits with return code 0 if all frames were shown without \ +any errors. If some frames were shown, but there were some non-fatal \ +errors, possibly causing an incomplete backtrace, the program exits \ +with return code 1. If no frames could be shown, or a fatal error \ +occured the program exits with return code 2. If the program was \ +invoked with bad or missing arguments it will exit with return code 64.") + }; + + argp_parse (&argp, argc, argv, 0, NULL, NULL); + + if (show_modules) + { + printf ("PID %d - %s module memory map\n", dwfl_pid (dwfl), + pid != 0 ? "process" : "core"); + if (dwfl_getmodules (dwfl, module_callback, NULL, 0) != 0) + error (EXIT_BAD, 0, "dwfl_getmodules: %s", dwfl_errmsg (-1)); + } + + struct frames frames; + /* When maxframes is zero, then 2048 is just the initial allocation + that will be increased using realloc in framecallback (). */ + frames.allocated = maxframes == 0 ? 2048 : maxframes; + frames.frames = 0; + frames.frame = malloc (sizeof (struct frame) * frames.allocated); + if (frames.frame == NULL) + error (EXIT_BAD, errno, "malloc frames.frame"); + + if (show_one_tid) + { + int err = 0; + switch (dwfl_getthread_frames (dwfl, pid, frame_callback, &frames)) + { + case DWARF_CB_OK: + case DWARF_CB_ABORT: + break; + case -1: + err = dwfl_errno (); + break; + default: + abort (); + } + print_frames (&frames, pid, err, "dwfl_getthread_frames"); + } + else + { + printf ("PID %d - %s\n", dwfl_pid (dwfl), pid != 0 ? "process" : "core"); + switch (dwfl_getthreads (dwfl, thread_callback, &frames)) + { + case DWARF_CB_OK: + case DWARF_CB_ABORT: + break; + case -1: + error (0, 0, "dwfl_getthreads: %s", dwfl_errmsg (-1)); + break; + default: + abort (); + } + } + free (frames.frame); + dwfl_end (dwfl); + + if (core != NULL) + elf_end (core); + + if (core_fd != -1) + close (core_fd); + +#ifdef USE_DEMANGLE + free (demangle_buffer); +#endif + + if (! frames_shown) + error (EXIT_BAD, 0, N_("Couldn't show any frames.")); + + return error_message_count != 0 ? EXIT_ERROR : EXIT_OK; +} |