IABSD.fr/xenocara/xserver/os/backtrace.c

Branch : - branch - master - tag -

• Show log

  Commit

• Author : matthieu
  Date : 2010-07-27 19:02:24
  Hash : 95d684a0
  Message : Update to xserver 1.8. Tested by many. Ok oga@, todd@.

• xserver/os/backtrace.c

• /*
   * Copyright 2008 Red Hat, Inc.
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice (including the next
   * paragraph) shall be included in all copies or substantial portions of the
   * Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
   * DEALINGS IN THE SOFTWARE.
   */
  
  #ifdef HAVE_DIX_CONFIG_H
  #include <dix-config.h>
  #endif
  
  #include "os.h"
  #include "misc.h"
  
  #ifdef HAVE_BACKTRACE
  #ifndef _GNU_SOURCE
  #define _GNU_SOURCE
  #endif
  #include <dlfcn.h>
  #include <execinfo.h>
  
  void xorg_backtrace(void)
  {
      void *array[64];
      const char *mod;
      int size, i;
      Dl_info info;
      ErrorF("\nBacktrace:\n");
      size = backtrace(array, 64);
      for (i = 0; i < size; i++) {
  	dladdr(array[i], &info);
  	mod = (info.dli_fname && *info.dli_fname) ? info.dli_fname : "(vdso)";
  	if (info.dli_saddr)
  	    ErrorF("%d: %s (%s+0x%lx) [%p]\n", i, mod,
  		   info.dli_sname, (long unsigned int)((char *) array[i] - (char *) info.dli_saddr), array[i]);
  	else
  	    ErrorF("%d: %s (%p+0x%lx) [%p]\n", i, mod,
  		   info.dli_fbase, (long unsigned int)((char *) array[i] - (char *) info.dli_fbase), array[i]);
      }
  }
  
  #else /* not glibc or glibc < 2.1 */
  
  # if defined(sun) && defined(__SVR4)
  #  define HAVE_PSTACK
  # endif
  
  # if defined(HAVE_WALKCONTEXT) /* Solaris 9 & later */
  
  # include <ucontext.h>
  # include <signal.h>
  # include <dlfcn.h>
  # include <sys/elf.h>
  
  #ifdef _LP64
  # define ElfSym Elf64_Sym
  #else
  # define ElfSym Elf32_Sym
  #endif
  
  /* Called for each frame on the stack to print it's contents */
  static int xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
  {
      Dl_info dlinfo;
      ElfSym *dlsym;
      char header[32];
      int depth = *((int *) arg);
  
      if (signo) {
  	char signame[SIG2STR_MAX];
  
  	if (sig2str(signo, signame) != 0) {
  	    strcpy(signame, "unknown");
  	}
  
  	ErrorF("** Signal %d (%s)\n", signo, signame);
      }
  
      snprintf(header, sizeof(header), "%d: 0x%lx", depth, pc);
      *((int *) arg) = depth + 1;
  
      /* Ask system dynamic loader for info on the address */
      if (dladdr1((void *) pc, &dlinfo, (void **) &dlsym, RTLD_DL_SYMENT)) {
  	unsigned long offset = pc - (uintptr_t) dlinfo.dli_saddr;
  	const char *symname;
  	
  	if (offset < dlsym->st_size) { /* inside a function */
  	    symname = dlinfo.dli_sname;
  	} else { /* found which file it was in, but not which function */
  	    symname = "<section start>";
  	    offset = pc - (uintptr_t)dlinfo.dli_fbase;
  	}
  	ErrorF("%s: %s:%s+0x%lx\n", header, dlinfo.dli_fname,
  	       symname, offset);
  
      } else {
  	/* Couldn't find symbol info from system dynamic loader, should
  	 * probably poke elfloader here, but haven't written that code yet,
  	 * so we just print the pc.
  	 */
  	ErrorF("%s\n", header);
      }
  
      return 0;
  }
  # endif /* HAVE_WALKCONTEXT */
  
  # ifdef HAVE_PSTACK
  static int xorg_backtrace_pstack(void) {
      pid_t kidpid;
      int pipefd[2];
  
      if (pipe(pipefd) != 0) {
  	return -1;
      }
  
      kidpid = fork1();
  
      if (kidpid == -1) {
  	/* ERROR */
  	return -1;
      } else if (kidpid == 0) {
  	/* CHILD */
  	char parent[16];
  	
  	seteuid(0);
  	close(STDIN_FILENO);
  	close(STDOUT_FILENO);
  	dup2(pipefd[1],STDOUT_FILENO);
  	closefrom(STDERR_FILENO);
  
  	snprintf(parent, sizeof(parent), "%d", getppid());
  	execle("/usr/bin/pstack", "pstack", parent, NULL);
  	exit(1);
      } else {
  	/* PARENT */
  	char btline[256];
  	int kidstat;
  	int bytesread;
  	int done = 0;
  	
  	close(pipefd[1]);
  
  	while (!done) {
  	    bytesread = read(pipefd[0], btline, sizeof(btline) - 1);
  
  	    if (bytesread > 0) {
  		btline[bytesread] = 0;
  		ErrorF("%s", btline);
  	    }
  	    else if ((bytesread < 0) ||
  		     ((errno != EINTR) && (errno != EAGAIN)))
  		done = 1;
  	}
  	close(pipefd[0]);
  	waitpid(kidpid, &kidstat, 0);
  	if (kidstat != 0)
  	    return -1;
      }
      return 0;
  }
  # endif /* HAVE_PSTACK */
  
  
  # if defined(HAVE_PSTACK) || defined(HAVE_WALKCONTEXT)
  
  void xorg_backtrace(void) {
  
      ErrorF("\nBacktrace:\n");
  
  #  ifdef HAVE_PSTACK
  /* First try fork/exec of pstack - otherwise fall back to walkcontext
     pstack is preferred since it can print names of non-exported functions */
  
      if (xorg_backtrace_pstack() < 0)
  #  endif	
      {
  #  ifdef HAVE_WALKCONTEXT
  	ucontext_t u;
  	int depth = 1;
  	
  	if (getcontext(&u) == 0)
  	    walkcontext(&u, xorg_backtrace_frame, &depth);
  	else
  #  endif
  	    Error("Failed to get backtrace info");
      }
      ErrorF("\n");	
  }
  
  # else
  
  /* Default fallback if we can't find any way to get a backtrace */
  void xorg_backtrace(void) { return; }
  
  # endif
  #endif