commit 861c0ef37bcfcae56d88572cb01c18bcfe1faded
author Christopher Ferris <cferris@google.com> Thu Jul 24 17:52:23 2014 -0700
committer Christopher Ferris <cferris@google.com> Tue Jul 29 18:10:00 2014 -0700
tree f63fc703a50b23213537962e4f60519f8b34db47
parent a7dc7600fe1be1f3fd61856b407bb7065307e711

Use libunwindbacktrace for debug malloc code.

Create a method of disabling the debug allocation code paths so that
it's possible to use the libunwindbacktrace library without any
modifications.

Use this path to create and destroy the maps for the process. It's not
stricly necessary in the init code since the symbols are not modified
until after the initialize calls.

Also, remove the debug_XXX source files that doesn't need to be in libc.so.

Fix the maps reading code since it was completely broken for 64 bit.

Bug: 16408686

Change-Id: I6b02ef6ce26fdb7a59ad1029e7cbba9accceb704

libc/bionic/debug_stacktrace.cpp

diff --git a/libc/bionic/debug_stacktrace.cpp b/libc/bionic/debug_stacktrace.cpp
index 713e761..b86e2af 100644
--- a/libc/bionic/debug_stacktrace.cpp
+++ b/libc/bionic/debug_stacktrace.cpp
@@ -35,6 +35,7 @@
 #include <sys/types.h>
 
 #include "debug_mapinfo.h"
+#include "malloc_debug_disable.h"
 #include "private/libc_logging.h"
 
 #if defined(__LP64__)
@@ -56,6 +57,8 @@
 static DemanglerFn g_demangler_fn = NULL;
 
 __LIBC_HIDDEN__ void backtrace_startup() {
+  ScopedDisableDebugCalls disable;
+
   g_map_info = mapinfo_create(getpid());
   g_demangler = dlopen("libgccdemangle.so", RTLD_NOW);
   if (g_demangler != NULL) {
@@ -65,6 +68,8 @@
 }
 
 __LIBC_HIDDEN__ void backtrace_shutdown() {
+  ScopedDisableDebugCalls disable;
+
   mapinfo_destroy(g_map_info);
   dlclose(g_demangler);
 }
@@ -98,7 +103,7 @@
     return _URC_NO_REASON;
   }
 
-#ifdef __arm__
+#if defined(__arm__)
   /*
    * The instruction pointer is pointing at the instruction after the bl(x), and
    * the _Unwind_Backtrace routine already masks the Thumb mode indicator (LSB
@@ -121,12 +126,16 @@
 }
 
 __LIBC_HIDDEN__ int get_backtrace(uintptr_t* frames, size_t max_depth) {
+  ScopedDisableDebugCalls disable;
+
   stack_crawl_state_t state(frames, max_depth);
   _Unwind_Backtrace(trace_function, &state);
   return state.frame_count;
 }
 
 __LIBC_HIDDEN__ void log_backtrace(uintptr_t* frames, size_t frame_count) {
+  ScopedDisableDebugCalls disable;
+
   uintptr_t self_bt[16];
   if (frames == NULL) {
     frame_count = get_backtrace(self_bt, 16);
@@ -146,7 +155,7 @@
       symbol = info.dli_sname;
     }
 
-    uintptr_t rel_pc;
+    uintptr_t rel_pc = offset;
     const mapinfo_t* mi = (g_map_info != NULL) ? mapinfo_find(g_map_info, frames[i], &rel_pc) : NULL;
     const char* soname = (mi != NULL) ? mi->name : info.dli_fname;
     if (soname == NULL) {