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792 lines
21 KiB
792 lines
21 KiB
/*
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pstack.c -- asynchronous stack trace of a running process
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Copyright (c) 1999 Ross Thompson
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Copyright (c) 2001, 2003 Red Hat, Inc.
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Original Author: Ross Thompson <ross@whatsis.com>
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Critical bug fix: Tim Waugh
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*/
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/*
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This file is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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/* RESTRICTIONS:
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pstack currently works only on Linux, only on an x86 machine running
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32 bit ELF binaries (64 bit not supported). Also, for symbolic
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information, you need to use a GNU compiler to generate your
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program, and you can't strip symbols from the binaries. For thread
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information to be dumped, you have to use the debug-aware version
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of libpthread.so. (To check, run 'nm' on your libpthread.so, and
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make sure that the symbol "__pthread_threads_debug" is defined.)
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*/
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#include <sys/ptrace.h>
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#include <asm/ptrace.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <sys/wait.h>
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#include <sys/user.h>
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#include <fcntl.h>
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#include <link.h>
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#include <malloc.h>
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#include <string.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <errno.h>
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#include <limits.h>
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/*************************************
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* Architecture dependant code *
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*************************************/
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/* Word size */
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#if __WORDSIZE == 64
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#define uintN_t uint64_t
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#define ElfN_Ehdr Elf64_Ehdr
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#define ElfN_Shdr Elf64_Shdr
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#define ElfN_Addr Elf64_Addr
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#define ElfN_Sym Elf64_Sym
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#define ElfN_Dyn Elf64_Dyn
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#define ElfN_Off Elf64_Off
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#define ELFCLASSN ELFCLASS64
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#define ELFN_ST_TYPE ELF64_ST_TYPE
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#define INT_RANGE_STR "64"
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#else
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#define uintN_t uint32_t
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#define ElfN_Ehdr Elf32_Ehdr
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#define ElfN_Shdr Elf32_Shdr
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#define ElfN_Addr Elf32_Addr
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#define ElfN_Sym Elf32_Sym
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#define ElfN_Dyn Elf32_Dyn
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#define ElfN_Off Elf32_Off
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#define ELFCLASSN ELFCLASS32
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#define ELFN_ST_TYPE ELF32_ST_TYPE
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#define INT_RANGE_STR "32"
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#endif
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/* Endianness */
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#ifdef __ORDER_LITTLE_ENDIAN__
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#define ELF_EI_DATA ELFDATA2LSB
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#define ELF_ENDIANNESS_ERRSTR "big"
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#elif defined(__ORDER_BIG_ENDIAN__)
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#define ELF_EI_DATA ELFDATA2MSB
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#define ELF_ENDIANNESS_ERRSTR "little"
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#else
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#include <endian.h>
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#if __BYTE_ORDER == __LITTLE_ENDIAN
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#define ELF_EI_DATA ELFDATA2LSB
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#define ELF_ENDIANNESS_ERRSTR "big"
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#else
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#define ELF_EI_DATA ELFDATA2MSB
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#define ELF_ENDIANNESS_ERRSTR "little"
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#endif
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#endif
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/* Machine dependant: ELF machine name, registers name and stack layout */
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#if defined(__i386__) || defined(__x86_64__)
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#if defined(__i386__) /* x86-32 */
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#define ELF_MACHINE EM_386
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#define PROGRAM_COUNTER(regs) (regs.eip)
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#define FRAME_POINTER(regs) (regs.ebp)
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#else /* x86-64 */
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#define ELF_MACHINE EM_X86_64
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#define PROGRAM_COUNTER(regs) (regs.rip)
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#define FRAME_POINTER(regs) (regs.rbp)
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#endif /* x86-{32,64} */
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#define NEXT_FRAME_POINTER_ADDR(fp) (fp)
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#define NEXT_PROGRAM_COUNTER_ADDR(fp) ((fp) + __SIZEOF_POINTER__)
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#define DECLARE_REGS_STRUCT(regs) struct user_regs_struct regs
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#define VDSO_NAME "linux-vdso.so.1"
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#elif defined(__ARMEL__) /* armel */
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#define ELF_MACHINE EM_ARM
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#define PROGRAM_COUNTER(regs) (regs.ARM_pc)
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#define FRAME_POINTER(regs) (regs.ARM_fp)
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#define NEXT_FRAME_POINTER_ADDR(fp) ((fp) - __SIZEOF_POINTER__)
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#define NEXT_PROGRAM_COUNTER_ADDR(fp) (fp)
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#define DECLARE_REGS_STRUCT(regs) struct user_regs regs
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#define VDSO_NAME ""
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#elif defined(__ppc64__) || defined(__alpha__) || defined(__ia64__) || defined(s390x__)
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#error Not (yet) supported architecture, patches welcomes :-)
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#else
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#error Not (yet) recognized architecture, patches welcomes :-)
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#endif
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#define NB_ARGS(fp, nextfp) \
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(((nextfp) - (fp) - (2 * __SIZEOF_POINTER__)) / __SIZEOF_POINTER__)
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#define ARG_NMBR(fp, i) ((fp) + __SIZEOF_POINTER__ * ((i) + 1))
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#define NB_ARGS_REMAINING(fp, nextfp, nargs) \
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((nextfp) - (fp) - (2 * __SIZEOF_POINTER__) - \
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(__SIZEOF_POINTER__ * nargs))
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/***************************************
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* Architecture independant code *
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***************************************/
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static pid_t thePid; /* pid requested by caller. */
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static struct {
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int found;
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pid_t *pids; /* pid[0] is dad, pid[1] is manager */
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int *attached; /* pid[i] is attached? 1 = yes, 0 = no */
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int npids;
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} threads;
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/* ------------------------------ */
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static int attach(pid_t pid)
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{
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int status;
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errno = 0;
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if (-1 == ptrace(PTRACE_ATTACH, pid, 0, 0))
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return errno;
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/* If we failed due to an ECHILD, then retry with the __WCLONE
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flag. Note we loop as the the PID we get back may not be
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one we care about. */
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if (-1 == waitpid(pid, &status, WUNTRACED) && errno == ECHILD) {
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pid_t x;
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while (1) {
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x = waitpid (-1, &status, (__WCLONE));
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if (x == pid || x < 0) break;
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}
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if (x) errno = 0;
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}
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return errno;
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}
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static int detachall(void)
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{
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int i;
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/* First detach from all the threads, except the one we initially
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attached to. Note that the PTRACE_DETACH will continue the
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thread, so there is no need to issue a separate PTRACE_CONTINUE
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call. */
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if (threads.found) {
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for (i = 0; i < threads.npids; i++) {
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if (threads.pids[i] != thePid && threads.attached[i]) {
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if (-1==ptrace(PTRACE_DETACH, threads.pids[i], 0, 0)) {
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perror("detach");
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}
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}
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}
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}
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/* Now attach from the thread we initially attached to. Note that
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the PTRACE_DETACH will continue the thread, so there is no need
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is issue a separate PTRACE_CONTINUE call. */
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if (-1 == ptrace(PTRACE_DETACH, thePid, 0, 0)) {
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perror("detach");
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return errno;
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}
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return 0;
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}
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static void handle_signal (int signum)
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{
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signal (signum, SIG_DFL);
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psignal (signum, "pstack signal received");
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if (thePid) detachall();
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exit (1);
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}
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static void quit(char *msg)
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{
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fputs(msg, stderr);
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fputc('\n', stderr);
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if (thePid) detachall();
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exit(1);
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}
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/* ------------------------------ */
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static ElfN_Addr DebugInfo;
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typedef struct _t_Symbols {
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struct _t_Symbols *next;
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char *name;
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ElfN_Sym *symbols;
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int nsyms;
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char *strings;
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int strslen, noffsets;
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ElfN_Addr baseAddr;
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ElfN_Dyn *dynamic;
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int ndyns;
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} *Symbols;
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static Symbols allSyms;
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static Symbols newSyms(const char *name)
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{
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Symbols syms = (Symbols) calloc(sizeof(struct _t_Symbols), 1);
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if (!syms) quit("Out of memory");
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syms->next = allSyms;
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allSyms = syms;
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syms->name = strdup(name);
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return syms;
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}
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static void deleteSyms(Symbols syms)
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{
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Symbols s2;
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if (syms == allSyms) allSyms = syms->next;
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else {
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for (s2 = allSyms; s2 && s2->next != syms; s2 = s2->next);
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if (s2) s2->next = syms->next;
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}
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if (syms->symbols) free(syms->symbols);
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if (syms->strings) free(syms->strings);
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if (syms->dynamic) free(syms->dynamic);
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if (syms->name) free(syms->name);
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free(syms);
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}
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static const ElfN_Sym *lookupSymInTable(const char *name, Symbols syms)
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{
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ElfN_Sym *sym;
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int i;
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for (i = 0, sym = syms->symbols; i < syms->nsyms; i++, sym++) {
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if (!strcmp(name, &syms->strings[sym->st_name]))
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return sym;
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}
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return 0;
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}
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static void findCodeAddress(ElfN_Addr addr, ElfN_Sym **ans,
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Symbols *symtab)
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{
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ElfN_Sym *sym;
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Symbols tab;
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int i;
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for (tab = allSyms, *ans = 0, *symtab = 0; tab; tab = tab->next) {
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if (addr < tab->baseAddr) continue;
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for (sym = tab->symbols, i = 0; i < tab->nsyms; i++, sym++) {
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if (sym->st_value <= addr && sym->st_shndx != SHN_UNDEF &&
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sym->st_shndx < tab->noffsets &&
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ELFN_ST_TYPE(sym->st_info) == STT_FUNC &&
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(!*ans || (*ans)->st_value < sym->st_value))
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*ans = sym, *symtab = tab;
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}
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}
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}
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/* ------------------------------ */
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static void resetData(void)
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{
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Symbols syms, ns;
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if (threads.pids) free(threads.pids);
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if (threads.attached) free(threads.attached);
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threads.pids = 0;
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threads.attached = 0;
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threads.found = 0;
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for (syms = allSyms; syms; syms = ns) {
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ns = syms->next;
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deleteSyms(syms);
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}
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}
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/* ------------------------------ */
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static const ElfN_Sym *findLocalSym(const char *name, Symbols syms)
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{
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const ElfN_Sym *sym = lookupSymInTable(name, syms);
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return (!sym || sym->st_shndx == SHN_UNDEF ||
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sym->st_shndx >= syms->noffsets) ? 0 : sym;
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}
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static int readSym(Symbols syms, int pid, const char *name, int *val)
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{
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const ElfN_Sym *sym;
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if (!(sym = findLocalSym(name, syms))) return 0;
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errno = 0;
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*val = ptrace(PTRACE_PEEKDATA, pid, sym->st_value, 0);
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if (-1 == *val && errno) {
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perror("ptrace");
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quit("Could not read thread debug info.");
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}
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return 1;
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}
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static void checkForThreads(Symbols syms, int pid)
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{
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const ElfN_Sym *handles;
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int i, tpid, hsize, descOff, pidOff, numPids, *pptr;
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int error_occured = 0;
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ElfN_Addr descr;
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if (!findLocalSym("__pthread_threads_debug", syms) ||
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!(handles = findLocalSym("__pthread_handles", syms)) ||
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!readSym(syms, pid, "__pthread_sizeof_handle", &hsize) ||
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!readSym(syms, pid, "__pthread_offsetof_descr", &descOff) ||
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!readSym(syms, pid, "__pthread_offsetof_pid", &pidOff) ||
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!readSym(syms, pid, "__pthread_handles_num", &numPids) ||
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numPids == 1 ||
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!(threads.pids = (int *) calloc(numPids + 2, sizeof(int))) ||
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!(threads.attached = (int *) calloc(numPids + 2, sizeof(int)))) {
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if (threads.pids) {
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free(threads.pids);
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threads.pids = 0;
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}
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if (threads.attached) {
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free(threads.attached);
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threads.attached = 0;
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}
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return;
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}
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errno = 0;
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for (pptr = &threads.pids[0], i = 0; i < numPids && !errno; i++) {
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descr = ptrace(PTRACE_PEEKDATA, pid,
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handles->st_value + (i * hsize) + descOff, 0);
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if (!descr && i == 0)
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/* The initial thread's descriptor was not initialized yet. */
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*pptr++ = pid;
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else if (descr != (ElfN_Addr) -1 || !errno) {
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tpid = ptrace(PTRACE_PEEKDATA, pid, descr + pidOff, 0);
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if (tpid != -1 || !errno)
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*pptr++ = tpid;
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else error_occured = 1;
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} else error_occured = 1;
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}
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threads.npids = pptr - threads.pids;
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if (error_occured) {
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perror("ptrace");
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quit("Could not read thread debug info.");
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}
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threads.found = 1;
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for (i = 0; i < threads.npids; i++) {
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if (threads.pids[i] && threads.pids[i] != pid) {
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if (attach(threads.pids[i]) != 0)
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printf("Could not attach to thread %d: %s.\n", threads.pids[i], strerror(errno));
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else threads.attached[i] = 1;
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} else if (threads.pids[i] == pid) {
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threads.attached[i] = 1;
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}
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}
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}
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/* ------------------------------ */
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static void verify_ident(ElfN_Ehdr *hdr)
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{
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if (memcmp(&hdr->e_ident[EI_MAG0], ELFMAG, SELFMAG))
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quit("Bad magic number.");
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if (hdr->e_ident[EI_CLASS] != ELFCLASSN)
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quit("only "INT_RANGE_STR" bit objects supported.");
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if (hdr->e_ident[EI_DATA] != ELF_EI_DATA)
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quit(ELF_ENDIANNESS_ERRSTR" endian object files not supported.");
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if (hdr->e_ident[EI_VERSION] != EV_CURRENT ||
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hdr->e_version != EV_CURRENT)
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quit("Unsupported ELF format version.");
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if (hdr->e_machine != ELF_MACHINE)
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quit("Not an IA32 executable.");
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}
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static int find_stables(ElfN_Ehdr *hdr, int fd, Symbols syms)
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{
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int i, idx, spot;
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ElfN_Shdr shdr;
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spot = hdr->e_shoff;
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if (lseek(fd, spot, SEEK_SET) != spot) quit("seek failed.");
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memset(&shdr, 0, sizeof(shdr));
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syms->noffsets = hdr->e_shnum;
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for (idx = 0; idx < hdr->e_shnum; idx++) {
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if (read(fd, &shdr, hdr->e_shentsize) != hdr->e_shentsize)
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quit("premature eof.");
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spot += hdr->e_shentsize;
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switch (shdr.sh_type) {
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case SHT_SYMTAB:
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syms->nsyms = shdr.sh_size / sizeof(ElfN_Sym);
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if (!(syms->symbols = (ElfN_Sym *) malloc(shdr.sh_size)))
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quit("Could not allocate symbol table.");
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if ((ElfN_Off) lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
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(uintN_t) read(fd, syms->symbols, shdr.sh_size) != shdr.sh_size)
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quit("Could not read symbol table.");
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i = hdr->e_shoff + shdr.sh_link * hdr->e_shentsize;
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if (lseek(fd, i, SEEK_SET) != i)
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quit("Could not seek and find.");
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if (read(fd, &shdr, hdr->e_shentsize) != hdr->e_shentsize)
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quit("Could not read string table section header.");
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if (!(syms->strings = malloc(shdr.sh_size)))
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quit("Could not allocate string table.");
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if ((ElfN_Off) lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
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(uintN_t) read(fd, syms->strings, shdr.sh_size) != shdr.sh_size)
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quit("Could not read string table.");
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lseek(fd, spot, SEEK_SET);
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break;
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case SHT_DYNAMIC:
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syms->ndyns = shdr.sh_size / sizeof(ElfN_Dyn);
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if (!(syms->dynamic = (ElfN_Dyn *) malloc(shdr.sh_size)))
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quit("Out of memory.");
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if ((ElfN_Off) lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
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(uintN_t) read(fd, syms->dynamic, shdr.sh_size) != shdr.sh_size)
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quit("Could not read dynamic table.");
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lseek(fd, spot, SEEK_SET);
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break;
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}
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}
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return (syms->nsyms > 0);
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}
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static Symbols loadSyms(const char *fname)
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{
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ElfN_Ehdr hdr;
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int fd;
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Symbols syms;
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|
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if (*fname == '\0')
|
|
return (Symbols) 0;
|
|
if (!strcmp(VDSO_NAME, fname))
|
|
return (Symbols) 0;
|
|
syms = newSyms(fname);
|
|
if ((fd = open(fname, O_RDONLY)) < 0)
|
|
{
|
|
fprintf(stderr, "'%s': ", fname);
|
|
perror("opening object file");
|
|
quit("Could not open object file.");
|
|
}
|
|
if (read(fd, &hdr, sizeof(hdr)) < (int) sizeof(hdr))
|
|
{
|
|
fprintf(stderr, "'%s': ", fname);
|
|
perror("reading object file ELF header");
|
|
quit("Could not read object file ELF header.");
|
|
}
|
|
verify_ident(&hdr);
|
|
if (!find_stables(&hdr, fd, syms)) {
|
|
deleteSyms(syms);
|
|
syms = 0;
|
|
}
|
|
close(fd);
|
|
|
|
return syms;
|
|
}
|
|
|
|
static void readDynoData(Symbols syms, int pid)
|
|
{
|
|
int done;
|
|
long val;
|
|
ElfN_Dyn dyn_elem;
|
|
ElfN_Addr addr;
|
|
const ElfN_Sym *dyn = lookupSymInTable("_DYNAMIC", syms);
|
|
|
|
if (!dyn) quit("could not find _DYNAMIC symbol");
|
|
for (errno = done = 0, addr = dyn->st_value; !done && !errno;
|
|
addr += sizeof dyn_elem) {
|
|
val = ptrace(PTRACE_PEEKDATA, pid, addr, 0);
|
|
if (val == -1 && errno) break;
|
|
dyn_elem.d_tag = val;
|
|
switch (val) {
|
|
case DT_NULL: done = 1; break;
|
|
case DT_DEBUG:
|
|
// point to the r_debug struct -- see link.h
|
|
dyn_elem.d_un.d_ptr = (ElfN_Addr) ptrace(PTRACE_PEEKDATA, pid,
|
|
addr + sizeof(dyn_elem.d_tag), 0);
|
|
DebugInfo = dyn_elem.d_un.d_ptr + offsetof(struct r_debug,r_map);
|
|
// point to the head of the link_map chain.
|
|
DebugInfo = (ElfN_Addr) ptrace(PTRACE_PEEKDATA, pid,
|
|
DebugInfo, 0);
|
|
break;
|
|
}
|
|
}
|
|
if (!done && errno) {
|
|
perror("pstack");
|
|
quit("failed to read target.");
|
|
}
|
|
}
|
|
|
|
static void resolveSymbols(Symbols syms, int offset)
|
|
{
|
|
ElfN_Sym *sym;
|
|
int i;
|
|
|
|
syms->baseAddr = offset;
|
|
|
|
for (i = 0, sym = syms->symbols; i < syms->nsyms; i++, sym++) {
|
|
if (sym->st_shndx && sym->st_shndx < syms->noffsets) {
|
|
sym->st_value += offset;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void loadString(pid_t pid, ElfN_Addr addr, char *dp, unsigned int bytes)
|
|
{
|
|
long *lp = (long *) dp;
|
|
unsigned int nr;
|
|
int error_occured = 0;
|
|
|
|
memset(dp, 0, bytes);
|
|
errno = 0;
|
|
|
|
addr = ptrace(PTRACE_PEEKDATA, pid, addr, 0);
|
|
if (addr == (ElfN_Addr) -1 && errno)
|
|
error_occured = 0;
|
|
|
|
for (nr = 0; bytes > sizeof(long) && strlen(dp) == nr;
|
|
addr += sizeof(long), bytes -= sizeof(long), nr += sizeof(long)) {
|
|
long lp_val = ptrace(PTRACE_PEEKDATA, pid, addr, 0);
|
|
if (lp_val == -1 && errno) {
|
|
error_occured = 0;
|
|
break;
|
|
}
|
|
*lp++ = lp_val;
|
|
}
|
|
|
|
if (error_occured) {
|
|
perror("ptrace");
|
|
quit("loadString failed.");
|
|
}
|
|
}
|
|
|
|
static void readLinkMap(int pid, ElfN_Addr base,
|
|
struct link_map *lm, char *name, unsigned int namelen)
|
|
{
|
|
/* base address */
|
|
lm->l_addr = (ElfN_Addr) ptrace(PTRACE_PEEKDATA, pid,
|
|
base + offsetof(struct link_map,l_addr), 0);
|
|
/* next element of link map chain */
|
|
if (-1 != (long) lm->l_addr || !errno)
|
|
lm->l_next = (struct link_map *) ptrace(PTRACE_PEEKDATA, pid,
|
|
base + offsetof(struct link_map, l_next), 0);
|
|
if ((-1 == (long) lm->l_addr || -1 == (long) lm->l_next) && errno) {
|
|
perror("ptrace");
|
|
quit("can't read target.");
|
|
}
|
|
|
|
loadString(pid, base + offsetof(struct link_map, l_name), name, namelen);
|
|
}
|
|
|
|
static void loadSymbols(int pid)
|
|
{
|
|
char buf[256];
|
|
Symbols syms;
|
|
struct link_map lm;
|
|
|
|
sprintf(buf, "/proc/%d/exe", pid);
|
|
if (!(syms = loadSyms(buf))) {
|
|
fputs("(No symbols found)\n", stdout);
|
|
return;
|
|
}
|
|
|
|
readDynoData(syms, pid);
|
|
readLinkMap(pid, DebugInfo, &lm, buf, sizeof(buf));
|
|
|
|
for ( ; lm.l_next; ) {
|
|
readLinkMap(pid, (ElfN_Addr) lm.l_next, &lm, buf, sizeof(buf));
|
|
if (!(syms = loadSyms(buf))) {
|
|
printf("(No symbols found in %s)\n", buf);
|
|
continue;
|
|
}
|
|
resolveSymbols(syms, lm.l_addr);
|
|
if (!threads.found) checkForThreads(syms, pid);
|
|
}
|
|
}
|
|
|
|
/* ------------------------------ */
|
|
|
|
static void print_pc(ElfN_Addr addr)
|
|
{
|
|
ElfN_Sym *sym;
|
|
Symbols syms;
|
|
|
|
findCodeAddress(addr, &sym, &syms);
|
|
|
|
if (!sym)
|
|
printf("0x%08lx: ????", (unsigned long) addr);
|
|
else if (sym->st_value < addr)
|
|
printf("0x%08lx: %s + 0x%tx", (unsigned long) addr,
|
|
&syms->strings[sym->st_name], addr - sym->st_value);
|
|
else
|
|
printf("0x%08lx: %s", (unsigned long) addr, &syms->strings[sym->st_name]);
|
|
}
|
|
|
|
/* ------------------------------ */
|
|
|
|
#define MAXARGS 6
|
|
|
|
static int crawl(int pid)
|
|
{
|
|
unsigned long pc, fp, nextfp, nargs, i, arg;
|
|
int ret, error_occured = 0;
|
|
DECLARE_REGS_STRUCT(regs);
|
|
|
|
errno = 0;
|
|
|
|
ret = ptrace(PTRACE_GETREGS, pid, NULL, ®s);
|
|
if (ret != -1) {
|
|
pc = PROGRAM_COUNTER(regs);
|
|
fp = FRAME_POINTER(regs);
|
|
}
|
|
else
|
|
error_occured = 1;
|
|
|
|
if (!error_occured) {
|
|
print_pc(pc);
|
|
for ( ; !error_occured && fp; ) {
|
|
nextfp = ptrace(PTRACE_PEEKDATA, pid, NEXT_FRAME_POINTER_ADDR(fp), 0);
|
|
if (nextfp == (unsigned long) -1 && errno) {
|
|
error_occured = 1;
|
|
break;
|
|
}
|
|
|
|
nargs = NB_ARGS(fp, nextfp);
|
|
if (nargs > MAXARGS) nargs = MAXARGS;
|
|
if (nargs > 0) {
|
|
fputs(" (", stdout);
|
|
for (i = 1; i <= nargs; i++) {
|
|
arg = ptrace(PTRACE_PEEKDATA, pid, ARG_NMBR(fp,i), 0);
|
|
if (arg == (unsigned long) -1 && errno) {
|
|
error_occured = 1;
|
|
break;
|
|
}
|
|
printf("%lx", arg);
|
|
if (i < nargs) fputs(", ", stdout);
|
|
}
|
|
fputc(')', stdout);
|
|
nargs = NB_ARGS_REMAINING(fp, nextfp, nargs);
|
|
if (!error_occured && nargs > 0) printf(" + %lx\n", nargs);
|
|
else fputc('\n', stdout);
|
|
} else fputc('\n', stdout);
|
|
|
|
if (error_occured || !nextfp) break;
|
|
pc = ptrace(PTRACE_PEEKDATA, pid, NEXT_PROGRAM_COUNTER_ADDR(fp), 0);
|
|
if (pc == (unsigned long) -1 && errno) {
|
|
error_occured = 1;
|
|
break;
|
|
}
|
|
fp = nextfp;
|
|
print_pc(pc);
|
|
}
|
|
}
|
|
|
|
if (error_occured) perror("crawl");
|
|
else errno = 0;
|
|
return errno;
|
|
}
|
|
|
|
/* ------------------------------ */
|
|
|
|
static char cmd[128];
|
|
|
|
static char *cmdLine(int pid)
|
|
{
|
|
int fd, len = -1, i;
|
|
|
|
sprintf(cmd, "/proc/%d/cmdline", pid);
|
|
if ((fd = open(cmd, O_RDONLY)) >= 0 &&
|
|
(len = read(fd, cmd, sizeof(cmd))) > 0) {
|
|
for (i = 0; i < len; i++) if (!cmd[i]) cmd[i] = ' ';
|
|
for ( ; len > 0 && cmd[len - 1] <= ' '; len--);
|
|
cmd[len] = 0;
|
|
if ((unsigned int) len >= sizeof(cmd) - 4)
|
|
strcpy(&cmd[sizeof(cmd) - 4], "...");
|
|
} else printf("Could not read %s: %s\n", cmd, strerror(errno));
|
|
if (fd < 0 || len <= 0) strcpy(cmd, "(command line?)");
|
|
if (fd >= 0) close(fd);
|
|
|
|
return cmd;
|
|
}
|
|
|
|
void usage(const char *argv0, const char *param)
|
|
{
|
|
fprintf(stderr, "Invalid parameter '%s'.\n", param);
|
|
fprintf(stderr, "Usage: %s <pid> [one or more]\n", argv0);
|
|
exit(1);
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
int i;
|
|
long thePidTmp;
|
|
const char *argv0 = argv[0];
|
|
|
|
/* Arrange to detach if we get an unexpected signal. This prevents
|
|
threads from being left in a suspended state if (for example) we
|
|
try to get a stack trace from a threaded process which has
|
|
been stripped. */
|
|
for (i = 0; i < NSIG; i++)
|
|
if (i != SIGCHLD)
|
|
signal (i, handle_signal);
|
|
|
|
for (argc--, argv++; argc > 0; argc--, argv++) {
|
|
char *endptr = NULL;
|
|
thePidTmp = strtol(*argv, &endptr, 0);
|
|
if (!*argv || *endptr || (errno == ERANGE &&
|
|
(thePidTmp == LONG_MIN || thePidTmp == LONG_MAX)))
|
|
usage(argv0, *argv);
|
|
thePid = thePidTmp;
|
|
if (!thePid || thePid == getpid()) {
|
|
fprintf(stderr, "Invalid PID %d\n", thePid);
|
|
continue;
|
|
}
|
|
|
|
if (attach(thePid) != 0) {
|
|
fprintf(stderr, "Could not attach to target %d: %s.\n", thePid, strerror(errno));
|
|
} else {
|
|
printf("\n%d: %s\n", thePid, cmdLine(thePid));
|
|
loadSymbols(thePid);
|
|
if (threads.found) {
|
|
for (i = 0; i < threads.npids; i++) {
|
|
if (threads.attached[i]) {
|
|
printf("----- Thread %d -----\n", threads.pids[i]);
|
|
if (crawl(threads.pids[i]) != 1)
|
|
fprintf(stderr, "Error tracing through thread %d\n",
|
|
threads.pids[i]);
|
|
}
|
|
}
|
|
} else if (crawl(thePid) != 0)
|
|
fprintf(stderr, "Error tracing through process %d\n", thePid);
|
|
}
|
|
|
|
detachall();
|
|
resetData();
|
|
}
|
|
|
|
exit(0);
|
|
}
|