| // Copyright (c) 2005 - 2007, 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 |
| |
| #include "utilities.h" |
| |
| extern "C" { |
| #define UNW_LOCAL_ONLY |
| #include <libunwind.h> |
| } |
| #include "glog/raw_logging.h" |
| #include "stacktrace.h" |
| |
| _START_GOOGLE_NAMESPACE_ |
| |
| // 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. |
| // We can use the GCC __thread syntax here since libunwind is not supported on |
| // Windows. |
| static __thread bool g_tl_entered; // Initialized to false. |
| |
| // If you change this function, also change GetStackFrames below. |
| int GetStackTrace(void** result, int max_depth, int skip_count) { |
| void *ip; |
| int n = 0; |
| unw_cursor_t cursor; |
| unw_context_t uc; |
| |
| if (g_tl_entered) { |
| return 0; |
| } |
| g_tl_entered = true; |
| |
| unw_getcontext(&uc); |
| RAW_CHECK(unw_init_local(&cursor, &uc) >= 0, "unw_init_local failed"); |
| skip_count++; // Do not include the "GetStackTrace" frame |
| |
| while (n < max_depth) { |
| int ret = unw_get_reg(&cursor, UNW_REG_IP, (unw_word_t *) &ip); |
| if (ret < 0) |
| break; |
| if (skip_count > 0) { |
| skip_count--; |
| } else { |
| result[n++] = ip; |
| } |
| ret = unw_step(&cursor); |
| if (ret <= 0) |
| break; |
| } |
| |
| g_tl_entered = false; |
| return n; |
| } |
| |
| _END_GOOGLE_NAMESPACE_ |