1 /* Unwinding of frames like gstack/pstack.
2 Copyright (C) 2013-2014 Red Hat, Inc.
3 This file is part of elfutils.
5 This file is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 elfutils is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include <stdio_ext.h>
28 #include ELFUTILS_HEADER(dwfl)
32 #include <printversion.h>
34 /* Name and version of program. */
35 ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;
37 /* Bug report address. */
38 ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;
40 /* non-printable argp options. */
41 #define OPT_DEBUGINFO 0x100
42 #define OPT_COREFILE 0x101
44 static bool show_activation = false;
45 static bool show_module = false;
46 static bool show_build_id = false;
47 static bool show_source = false;
48 static bool show_one_tid = false;
49 static bool show_quiet = false;
50 static bool show_raw = false;
51 static bool show_modules = false;
52 static bool show_debugname = false;
53 static bool show_inlines = false;
55 static int maxframes = 256;
70 static Dwfl *dwfl = NULL;
72 static int core_fd = -1;
73 static Elf *core = NULL;
74 static const char *exec = NULL;
75 static char *debuginfo_path = NULL;
77 static const Dwfl_Callbacks proc_callbacks =
79 .find_elf = dwfl_linux_proc_find_elf,
80 .find_debuginfo = dwfl_standard_find_debuginfo,
81 .debuginfo_path = &debuginfo_path,
84 static const Dwfl_Callbacks core_callbacks =
86 .find_elf = dwfl_build_id_find_elf,
87 .find_debuginfo = dwfl_standard_find_debuginfo,
88 .debuginfo_path = &debuginfo_path,
92 static size_t demangle_buffer_len = 0;
93 static char *demangle_buffer = NULL;
96 /* Whether any frames have been shown at all. Determines exit status. */
97 static bool frames_shown = false;
99 /* Program exit codes. All frames shown without any errors is GOOD.
100 Some frames shown with some non-fatal errors is an ERROR. A fatal
101 error or no frames shown at all is BAD. A command line USAGE exit
102 is generated by argp_error. */
106 #define EXIT_USAGE 64
109 get_addr_width (Dwfl_Module *mod)
111 // Try to find the address wide if possible.
112 static int width = 0;
113 if (width == 0 && mod)
116 Elf *elf = dwfl_module_getelf (mod, &bias);
120 GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem);
122 width = ehdr->e_ident[EI_CLASS] == ELFCLASS32 ? 8 : 16;
132 module_callback (Dwfl_Module *mod, void **userdata __attribute__((unused)),
133 const char *name, Dwarf_Addr start,
134 void *arg __attribute__((unused)))
136 /* Forces resolving of main elf and debug files. */
138 Elf *elf = dwfl_module_getelf (mod, &bias);
139 Dwarf *dwarf = dwfl_module_getdwarf (mod, &bias);
142 const char *mainfile;
143 const char *debugfile;
144 const char *modname = dwfl_module_info (mod, NULL, NULL, &end, NULL,
145 NULL, &mainfile, &debugfile);
146 assert (strcmp (modname, name) == 0);
148 int width = get_addr_width (mod);
149 printf ("0x%0*" PRIx64 "-0x%0*" PRIx64 " %s\n",
150 width, start, width, end, basename (name));
152 const unsigned char *id;
154 int id_len = dwfl_module_build_id (mod, &id, &id_vaddr);
159 printf ("%02" PRIx8, *id++);
160 while (--id_len > 0);
165 printf (" %s\n", mainfile != NULL ? mainfile : "-");
167 printf (" %s\n", debugfile != NULL ? debugfile : "-");
173 frame_callback (Dwfl_Frame *state, void *arg)
175 struct frames *frames = (struct frames *) arg;
176 int nr = frames->frames;
177 if (! dwfl_frame_pc (state, &frames->frame[nr].pc,
178 &frames->frame[nr].isactivation))
182 if (frames->frames == maxframes)
183 return DWARF_CB_ABORT;
185 if (frames->frames == frames->allocated)
187 frames->allocated *= 2;
188 frames->frame = realloc (frames->frame,
189 sizeof (struct frame) * frames->allocated);
190 if (frames->frame == NULL)
191 error (EXIT_BAD, errno, "realloc frames.frame");
198 die_name (Dwarf_Die *die)
200 Dwarf_Attribute attr;
202 name = dwarf_formstring (dwarf_attr_integrate (die,
203 DW_AT_MIPS_linkage_name,
205 ?: dwarf_attr_integrate (die,
209 name = dwarf_diename (die);
215 print_frame (int nr, Dwarf_Addr pc, bool isactivation,
216 Dwarf_Addr pc_adjusted, Dwfl_Module *mod,
217 const char *symname, Dwarf_Die *cudie,
220 int width = get_addr_width (mod);
221 printf ("#%-2u 0x%0*" PRIx64, nr, width, (uint64_t) pc);
224 printf ("%4s", ! isactivation ? "- 1" : "");
229 // Require GNU v3 ABI by the "_Z" prefix.
230 if (! show_raw && symname[0] == '_' && symname[1] == 'Z')
233 char *dsymname = __cxa_demangle (symname, demangle_buffer,
234 &demangle_buffer_len, &status);
236 symname = demangle_buffer = dsymname;
239 printf (" %s", symname);
244 fname = dwfl_module_info(mod, NULL, &start,
245 NULL, NULL, NULL, NULL, NULL);
249 printf (" - %s", fname);
254 const unsigned char *id;
256 int id_len = dwfl_module_build_id (mod, &id, &id_vaddr);
261 printf ("%02" PRIx8, *id++);
262 while (--id_len > 0);
263 printf ("]@0x%0" PRIx64 "+0x%" PRIx64,
264 start, pc_adjusted - start);
277 if (dwarf_getsrcfiles (cudie, &files, NULL) == 0)
279 Dwarf_Attribute attr;
281 if (dwarf_formudata (dwarf_attr (die, DW_AT_call_file, &attr),
284 sname = dwarf_filesrc (files, val, NULL, NULL);
285 if (dwarf_formudata (dwarf_attr (die, DW_AT_call_line,
289 if (dwarf_formudata (dwarf_attr (die, DW_AT_call_column,
298 Dwfl_Line *lineobj = dwfl_module_getsrc(mod, pc_adjusted);
300 sname = dwfl_lineinfo (lineobj, NULL, &line, &col, NULL, NULL);
305 printf ("\n %s", sname);
308 printf (":%d", line);
318 print_inline_frames (int *nr, Dwarf_Addr pc, bool isactivation,
319 Dwarf_Addr pc_adjusted, Dwfl_Module *mod,
320 const char *symname, Dwarf_Die *cudie, Dwarf_Die *die)
322 Dwarf_Die *scopes = NULL;
323 int nscopes = dwarf_getscopes_die (die, &scopes);
326 /* scopes[0] == die, the lowest level, for which we already have
327 the name. This is the actual source location where it
329 print_frame ((*nr)++, pc, isactivation, pc_adjusted, mod, symname,
332 /* last_scope is the source location where the next frame/function
334 Dwarf_Die *last_scope = &scopes[0];
335 for (int i = 1; i < nscopes && (maxframes == 0 || *nr < maxframes); i++)
337 Dwarf_Die *scope = &scopes[i];
338 int tag = dwarf_tag (scope);
339 if (tag != DW_TAG_inlined_subroutine
340 && tag != DW_TAG_entry_point
341 && tag != DW_TAG_subprogram)
344 symname = die_name (scope);
345 print_frame ((*nr)++, pc, isactivation, pc_adjusted, mod, symname,
348 /* Found the "top-level" in which everything was inlined? */
349 if (tag == DW_TAG_subprogram)
359 print_frames (struct frames *frames, pid_t tid, int dwflerr, const char *what)
361 if (frames->frames > 0)
364 printf ("TID %lld:\n", (long long) tid);
366 for (int nr = 0; nr < frames->frames && (maxframes == 0
367 || frame_nr < maxframes); nr++)
369 Dwarf_Addr pc = frames->frame[nr].pc;
370 bool isactivation = frames->frame[nr].isactivation;
371 Dwarf_Addr pc_adjusted = pc - (isactivation ? 0 : 1);
373 /* Get PC->SYMNAME. */
374 Dwfl_Module *mod = dwfl_addrmodule (dwfl, pc_adjusted);
375 const char *symname = NULL;
377 Dwarf_Die *die = NULL;
378 Dwarf_Die *cudie = NULL;
379 if (mod && ! show_quiet)
384 Dwarf_Die *scopes = NULL;
385 cudie = dwfl_module_addrdie (mod, pc_adjusted, &bias);
386 int nscopes = dwarf_getscopes (cudie, pc_adjusted - bias,
389 /* Find the first function-like DIE with a name in scope. */
390 for (int i = 0; symname == NULL && i < nscopes; i++)
392 Dwarf_Die *scope = &scopes[i];
393 int tag = dwarf_tag (scope);
394 if (tag == DW_TAG_subprogram
395 || tag == DW_TAG_inlined_subroutine
396 || tag == DW_TAG_entry_point)
397 symname = die_name (scope);
409 symname = dwfl_module_addrname (mod, pc_adjusted);
412 if (show_inlines && die != NULL)
413 print_inline_frames (&frame_nr, pc, isactivation, pc_adjusted, mod,
414 symname, cudie, die);
416 print_frame (frame_nr++, pc, isactivation, pc_adjusted, mod, symname,
420 if (frames->frames > 0 && frame_nr == maxframes)
421 error (0, 0, "tid %lld: shown max number of frames "
422 "(%d, use -n 0 for unlimited)", (long long) tid, maxframes);
423 else if (dwflerr != 0)
425 if (frames->frames > 0)
427 unsigned nr = frames->frames - 1;
428 Dwarf_Addr pc = frames->frame[nr].pc;
429 bool isactivation = frames->frame[nr].isactivation;
430 Dwarf_Addr pc_adjusted = pc - (isactivation ? 0 : 1);
431 Dwfl_Module *mod = dwfl_addrmodule (dwfl, pc_adjusted);
432 const char *mainfile = NULL;
433 const char *modname = dwfl_module_info (mod, NULL, NULL, NULL, NULL,
434 NULL, &mainfile, NULL);
435 if (modname == NULL || modname[0] == '\0')
437 if (mainfile != NULL)
440 modname = "<unknown>";
442 error (0, 0, "%s tid %lld at 0x%" PRIx64 " in %s: %s", what,
443 (long long) tid, pc_adjusted, modname, dwfl_errmsg (dwflerr));
446 error (0, 0, "%s tid %lld: %s", what, (long long) tid,
447 dwfl_errmsg (dwflerr));
452 thread_callback (Dwfl_Thread *thread, void *thread_arg)
454 struct frames *frames = (struct frames *) thread_arg;
455 pid_t tid = dwfl_thread_tid (thread);
458 switch (dwfl_thread_getframes (thread, frame_callback, thread_arg))
469 print_frames (frames, tid, err, "dwfl_thread_getframes");
474 parse_opt (int key, char *arg __attribute__ ((unused)),
475 struct argp_state *state)
482 argp_error (state, N_("-p PID should be a positive process id."));
486 core_fd = open (arg, O_RDONLY);
488 error (EXIT_BAD, errno, N_("Cannot open core file '%s'"), arg);
489 elf_version (EV_CURRENT);
490 core = elf_begin (core_fd, ELF_C_READ_MMAP, NULL);
492 error (EXIT_BAD, 0, "core '%s' elf_begin: %s", arg, elf_errmsg(-1));
500 debuginfo_path = arg;
512 show_activation = true;
516 show_debugname = true;
520 show_inlines = show_debugname = true;
524 show_activation = show_source = show_module = show_debugname = true;
529 show_build_id = true;
545 maxframes = atoi (arg);
548 argp_error (state, N_("-n MAXFRAMES should be 0 or higher."));
558 if (core == NULL && exec != NULL)
560 N_("-e EXEC needs a core given by --core."));
562 if (pid == 0 && show_one_tid == true)
564 N_("-1 needs a thread id given by -p."));
566 if ((pid == 0 && core == NULL) || (pid != 0 && core != NULL))
568 N_("One of -p PID or --core COREFILE should be given."));
572 dwfl = dwfl_begin (&proc_callbacks);
574 error (EXIT_BAD, 0, "dwfl_begin: %s", dwfl_errmsg (-1));
576 int err = dwfl_linux_proc_report (dwfl, pid);
578 error (EXIT_BAD, 0, "dwfl_linux_proc_report pid %lld: %s",
579 (long long) pid, dwfl_errmsg (-1));
581 error (EXIT_BAD, err, "dwfl_linux_proc_report pid %lld",
587 dwfl = dwfl_begin (&core_callbacks);
589 error (EXIT_BAD, 0, "dwfl_begin: %s", dwfl_errmsg (-1));
590 if (dwfl_core_file_report (dwfl, core, exec) < 0)
591 error (EXIT_BAD, 0, "dwfl_core_file_report: %s", dwfl_errmsg (-1));
594 if (dwfl_report_end (dwfl, NULL, NULL) != 0)
595 error (EXIT_BAD, 0, "dwfl_report_end: %s", dwfl_errmsg (-1));
599 int err = dwfl_linux_proc_attach (dwfl, pid, false);
601 error (EXIT_BAD, 0, "dwfl_linux_proc_attach pid %lld: %s",
602 (long long) pid, dwfl_errmsg (-1));
604 error (EXIT_BAD, err, "dwfl_linux_proc_attach pid %lld",
610 if (dwfl_core_file_attach (dwfl, core) < 0)
611 error (EXIT_BAD, 0, "dwfl_core_file_attach: %s", dwfl_errmsg (-1));
614 /* Makes sure we are properly attached. */
615 if (dwfl_pid (dwfl) < 0)
616 error (EXIT_BAD, 0, "dwfl_pid: %s\n", dwfl_errmsg (-1));
620 return ARGP_ERR_UNKNOWN;
626 main (int argc, char **argv)
628 /* We use no threads here which can interfere with handling a stream. */
629 __fsetlocking (stdin, FSETLOCKING_BYCALLER);
630 __fsetlocking (stdout, FSETLOCKING_BYCALLER);
631 __fsetlocking (stderr, FSETLOCKING_BYCALLER);
634 (void) setlocale (LC_ALL, "");
636 const struct argp_option options[] =
638 { NULL, 0, NULL, 0, N_("Input selection options:"), 0 },
639 { "pid", 'p', "PID", 0,
640 N_("Show stack of process PID"), 0 },
641 { "core", OPT_COREFILE, "COREFILE", 0,
642 N_("Show stack found in COREFILE"), 0 },
643 { "executable", 'e', "EXEC", 0, N_("(optional) EXECUTABLE that produced COREFILE"), 0 },
644 { "debuginfo-path", OPT_DEBUGINFO, "PATH", 0,
645 N_("Search path for separate debuginfo files"), 0 },
647 { NULL, 0, NULL, 0, N_("Output selection options:"), 0 },
648 { "activation", 'a', NULL, 0,
649 N_("Additionally show frame activation"), 0 },
650 { "debugname", 'd', NULL, 0,
651 N_("Additionally try to lookup DWARF debuginfo name for frame address"),
653 { "inlines", 'i', NULL, 0,
654 N_("Additionally show inlined function frames using DWARF debuginfo if available (implies -d)"), 0 },
655 { "module", 'm', NULL, 0,
656 N_("Additionally show module file information"), 0 },
657 { "source", 's', NULL, 0,
658 N_("Additionally show source file information"), 0 },
659 { "verbose", 'v', NULL, 0,
660 N_("Show all additional information (activation, debugname, inlines, module and source)"), 0 },
661 { "quiet", 'q', NULL, 0,
662 N_("Do not resolve address to function symbol name"), 0 },
663 { "raw", 'r', NULL, 0,
664 N_("Show raw function symbol names, do not try to demangle names"), 0 },
665 { "build-id", 'b', NULL, 0,
666 N_("Show module build-id, load address and pc offset"), 0 },
667 { NULL, '1', NULL, 0,
668 N_("Show the backtrace of only one thread"), 0 },
669 { NULL, 'n', "MAXFRAMES", 0,
670 N_("Show at most MAXFRAMES per thread (default 256, use 0 for unlimited)"), 0 },
671 { "list-modules", 'l', NULL, 0,
672 N_("Show module memory map with build-id, elf and debug files detected"), 0 },
673 { NULL, 0, NULL, 0, NULL, 0 }
676 const struct argp argp =
680 .doc = N_("Print a stack for each thread in a process or core file.\n\
682 Program exits with return code 0 if all frames were shown without \
683 any errors. If some frames were shown, but there were some non-fatal \
684 errors, possibly causing an incomplete backtrace, the program exits \
685 with return code 1. If no frames could be shown, or a fatal error \
686 occured the program exits with return code 2. If the program was \
687 invoked with bad or missing arguments it will exit with return code 64.")
690 argp_parse (&argp, argc, argv, 0, NULL, NULL);
694 printf ("PID %lld - %s module memory map\n", (long long) dwfl_pid (dwfl),
695 pid != 0 ? "process" : "core");
696 if (dwfl_getmodules (dwfl, module_callback, NULL, 0) != 0)
697 error (EXIT_BAD, 0, "dwfl_getmodules: %s", dwfl_errmsg (-1));
700 struct frames frames;
701 /* When maxframes is zero, then 2048 is just the initial allocation
702 that will be increased using realloc in framecallback (). */
703 frames.allocated = maxframes == 0 ? 2048 : maxframes;
705 frames.frame = malloc (sizeof (struct frame) * frames.allocated);
706 if (frames.frame == NULL)
707 error (EXIT_BAD, errno, "malloc frames.frame");
712 switch (dwfl_getthread_frames (dwfl, pid, frame_callback, &frames))
723 print_frames (&frames, pid, err, "dwfl_getthread_frames");
727 printf ("PID %lld - %s\n", (long long) dwfl_pid (dwfl),
728 pid != 0 ? "process" : "core");
729 switch (dwfl_getthreads (dwfl, thread_callback, &frames))
735 error (0, 0, "dwfl_getthreads: %s", dwfl_errmsg (-1));
751 free (demangle_buffer);
755 error (EXIT_BAD, 0, N_("Couldn't show any frames."));
757 return error_message_count != 0 ? EXIT_ERROR : EXIT_OK;