Squashed 'third_party/gperftools/' content from commit 54505f1
Change-Id: Id02e833828732b0efe7dac722b8485279e67c5fa
git-subtree-dir: third_party/gperftools
git-subtree-split: 54505f1d50c2d1f4676f5e87090b64a117fd980e
diff --git a/src/stacktrace_libunwind-inl.h b/src/stacktrace_libunwind-inl.h
new file mode 100644
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+++ b/src/stacktrace_libunwind-inl.h
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+// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
+// Copyright (c) 2005, Google Inc.
+// 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.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// 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.
+
+// ---
+// Author: Arun Sharma
+//
+// Produce stack trace using libunwind
+
+#ifndef BASE_STACKTRACE_LIBINWIND_INL_H_
+#define BASE_STACKTRACE_LIBINWIND_INL_H_
+// Note: this file is included into stacktrace.cc more than once.
+// Anything that should only be defined once should be here:
+
+// We only need local unwinder.
+#define UNW_LOCAL_ONLY
+
+extern "C" {
+#include <assert.h>
+#include <string.h> // for memset()
+#include <libunwind.h>
+}
+#include "gperftools/stacktrace.h"
+#include "base/logging.h"
+
+// Sometimes, we can try to get a stack trace from within a stack
+// trace, because libunwind can call mmap (maybe indirectly via an
+// internal mmap based memory allocator), and that mmap gets trapped
+// and causes a stack-trace request. If were to try to honor that
+// recursive request, we'd end up with infinite recursion or deadlock.
+// Luckily, it's safe to ignore those subsequent traces. In such
+// cases, we return 0 to indicate the situation.
+static __thread int recursive;
+
+#if defined(TCMALLOC_ENABLE_UNWIND_FROM_UCONTEXT) && (defined(__i386__) || defined(__x86_64__)) && defined(__GNU_LIBRARY__)
+#define BASE_STACKTRACE_UNW_CONTEXT_IS_UCONTEXT 1
+#endif
+
+#endif // BASE_STACKTRACE_LIBINWIND_INL_H_
+
+// Note: this part of the file is included several times.
+// Do not put globals below.
+
+// The following 4 functions are generated from the code below:
+// GetStack{Trace,Frames}()
+// GetStack{Trace,Frames}WithContext()
+//
+// These functions take the following args:
+// void** result: the stack-trace, as an array
+// int* sizes: the size of each stack frame, as an array
+// (GetStackFrames* only)
+// int max_depth: the size of the result (and sizes) array(s)
+// int skip_count: how many stack pointers to skip before storing in result
+// void* ucp: a ucontext_t* (GetStack{Trace,Frames}WithContext only)
+static int GET_STACK_TRACE_OR_FRAMES {
+ void *ip;
+ int n = 0;
+ unw_cursor_t cursor;
+ unw_context_t uc;
+#if IS_STACK_FRAMES
+ unw_word_t sp = 0, next_sp = 0;
+#endif
+
+ if (recursive) {
+ return 0;
+ }
+ ++recursive;
+
+#if (IS_WITH_CONTEXT && defined(BASE_STACKTRACE_UNW_CONTEXT_IS_UCONTEXT))
+ if (ucp) {
+ uc = *(static_cast<unw_context_t *>(const_cast<void *>(ucp)));
+ /* this is a bit weird. profiler.cc calls us with signal's ucontext
+ * yet passing us 2 as skip_count and essentially assuming we won't
+ * use ucontext. */
+ /* In order to fix that I'm going to assume that if ucp is
+ * non-null we're asked to ignore skip_count in case we're
+ * able to use ucp */
+ skip_count = 0;
+ } else {
+ unw_getcontext(&uc);
+ skip_count += 2; // Do not include current and parent frame
+ }
+#else
+ unw_getcontext(&uc);
+ skip_count += 2; // Do not include current and parent frame
+#endif
+
+ int ret = unw_init_local(&cursor, &uc);
+ assert(ret >= 0);
+
+ while (skip_count--) {
+ if (unw_step(&cursor) <= 0) {
+ goto out;
+ }
+#if IS_STACK_FRAMES
+ if (unw_get_reg(&cursor, UNW_REG_SP, &next_sp)) {
+ goto out;
+ }
+#endif
+ }
+
+ while (n < max_depth) {
+ if (unw_get_reg(&cursor, UNW_REG_IP, (unw_word_t *) &ip) < 0) {
+ break;
+ }
+#if IS_STACK_FRAMES
+ sizes[n] = 0;
+#endif
+ result[n++] = ip;
+ if (unw_step(&cursor) <= 0) {
+ break;
+ }
+#if IS_STACK_FRAMES
+ sp = next_sp;
+ if (unw_get_reg(&cursor, UNW_REG_SP, &next_sp) , 0) {
+ break;
+ }
+ sizes[n - 1] = next_sp - sp;
+#endif
+ }
+out:
+ --recursive;
+ return n;
+}