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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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|
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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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|
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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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|
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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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|
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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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|
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/* RESTRICTIONS: |
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|
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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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|
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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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|
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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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|
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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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|
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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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/* ------------------------------ */ |
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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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|
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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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/* ------------------------------ */ |
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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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|
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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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|
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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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|
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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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|
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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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|
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return (syms->nsyms > 0); |
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} |
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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') |
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return (Symbols) 0; |
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if (!strcmp(VDSO_NAME, fname)) |
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return (Symbols) 0; |
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syms = newSyms(fname); |
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if ((fd = open(fname, O_RDONLY)) < 0) |
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{ |
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fprintf(stderr, "'%s': ", fname); |
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perror("opening object file"); |
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quit("Could not open object file."); |
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} |
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if (read(fd, &hdr, sizeof(hdr)) < (int) sizeof(hdr)) |
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{ |
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fprintf(stderr, "'%s': ", fname); |
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perror("reading object file ELF header"); |
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quit("Could not read object file ELF header."); |
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} |
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verify_ident(&hdr); |
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if (!find_stables(&hdr, fd, syms)) { |
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deleteSyms(syms); |
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syms = 0; |
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} |
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close(fd); |
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|
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return syms; |
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} |
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|
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static void readDynoData(Symbols syms, int pid) |
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{ |
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int done; |
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long val; |
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ElfN_Dyn dyn_elem; |
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ElfN_Addr addr; |
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const ElfN_Sym *dyn = lookupSymInTable("_DYNAMIC", syms); |
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|
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if (!dyn) quit("could not find _DYNAMIC symbol"); |
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for (errno = done = 0, addr = dyn->st_value; !done && !errno; |
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addr += sizeof dyn_elem) { |
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val = ptrace(PTRACE_PEEKDATA, pid, addr, 0); |
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if (val == -1 && errno) break; |
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dyn_elem.d_tag = val; |
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switch (val) { |
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case DT_NULL: done = 1; break; |
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case DT_DEBUG: |
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// point to the r_debug struct -- see link.h |
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dyn_elem.d_un.d_ptr = (ElfN_Addr) ptrace(PTRACE_PEEKDATA, pid, |
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addr + sizeof(dyn_elem.d_tag), 0); |
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DebugInfo = dyn_elem.d_un.d_ptr + offsetof(struct r_debug,r_map); |
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// point to the head of the link_map chain. |
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DebugInfo = (ElfN_Addr) ptrace(PTRACE_PEEKDATA, pid, |
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DebugInfo, 0); |
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break; |
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} |
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} |
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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); |
|
}
|
|
|