Fix the duplication in the debugging code.
We had two copies of the backtrace code, and two copies of the
libcorkscrew /proc/pid/maps code. This patch gets us down to one.
We also had hacks so we could log in the malloc debugging code.
This patch pulls the non-allocating "printf" code out of the
dynamic linker so everyone can share.
This patch also makes the leak diagnostics easier to read, and
makes it possible to paste them directly into the 'stack' tool (by
using relative PCs).
This patch also fixes the stdio standard stream leak that was
causing a leak warning every time tf_daemon ran.
Bug: 7291287
Change-Id: I66e4083ac2c5606c8d2737cb45c8ac8a32c7cfe8
diff --git a/libc/bionic/debug_stacktrace.cpp b/libc/bionic/debug_stacktrace.cpp
new file mode 100644
index 0000000..4b080a4
--- /dev/null
+++ b/libc/bionic/debug_stacktrace.cpp
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "debug_stacktrace.h"
+
+#include <dlfcn.h>
+#include <unistd.h>
+#include <unwind.h>
+#include <sys/types.h>
+
+#include "debug_format.h"
+#include "debug_mapinfo.h"
+#include "logd.h"
+
+/* depends how the system includes define this */
+#ifdef HAVE_UNWIND_CONTEXT_STRUCT
+typedef struct _Unwind_Context __unwind_context;
+#else
+typedef _Unwind_Context __unwind_context;
+#endif
+
+static _Unwind_Reason_Code trace_function(__unwind_context* context, void* arg) {
+ stack_crawl_state_t* state = static_cast<stack_crawl_state_t*>(arg);
+ if (state->count) {
+ intptr_t ip = (intptr_t)_Unwind_GetIP(context);
+ if (ip) {
+ state->addrs[0] = ip;
+ state->addrs++;
+ state->count--;
+ return _URC_NO_REASON;
+ }
+ }
+ // If we run out of space to record the address or 0 has been seen, stop
+ // unwinding the stack.
+ return _URC_END_OF_STACK;
+}
+
+__LIBC_HIDDEN__ int get_backtrace(intptr_t* addrs, size_t max_entries) {
+ stack_crawl_state_t state;
+ state.count = max_entries;
+ state.addrs = addrs;
+ _Unwind_Backtrace(trace_function, &state);
+ return max_entries - state.count;
+}
+
+__LIBC_HIDDEN__ void log_backtrace(mapinfo_t* map_info, intptr_t* addrs, size_t c) {
+ intptr_t self_bt[16];
+ if (addrs == NULL) {
+ c = get_backtrace(self_bt, 16);
+ addrs = self_bt;
+ }
+
+ __libc_format_log(ANDROID_LOG_ERROR, "libc",
+ "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n");
+
+ int index = 0;
+ for (size_t i = 0 ; i < c; ++i) {
+ void* offset = 0;
+ const char* symbol = NULL;
+
+ Dl_info info;
+ if (dladdr((void*) addrs[i], &info) != 0) {
+ offset = info.dli_saddr;
+ symbol = info.dli_sname;
+ }
+
+ // This test is a bit sketchy, but it allows us to skip the
+ // stack trace entries due to this debugging code. it works
+ // because those don't have a symbol (they're not exported).
+ if (symbol != NULL || index > 0) {
+ unsigned int rel_pc;
+ const mapinfo_t* mi = mapinfo_find(map_info, addrs[i], &rel_pc);
+ const char* soname = mi ? mi->name : info.dli_fname;
+ if (soname == NULL) {
+ soname = "unknown";
+ }
+ if (symbol) {
+ __libc_format_log(ANDROID_LOG_ERROR, "libc", " #%02d pc %08x %s (%s+0x%x)",
+ index, rel_pc, soname, symbol, addrs[i] - (intptr_t)offset);
+ } else {
+ __libc_format_log(ANDROID_LOG_ERROR, "libc", " #%02d pc %08x %s",
+ index, rel_pc, soname);
+ }
+ ++index;
+ }
+ }
+}