1//===-- backtrace_linux_libc.cpp --------------------------------*- C++ -*-===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8 9#include <assert.h> 10#include <execinfo.h> 11#include <stddef.h> 12#include <stdint.h> 13#include <stdlib.h> 14#include <string.h> 15 16#include "gwp_asan/definitions.h" 17#include "gwp_asan/optional/backtrace.h" 18#include "gwp_asan/optional/printf.h" 19#include "gwp_asan/options.h" 20 21namespace { 22size_t Backtrace(uintptr_t *TraceBuffer, size_t Size) { 23 static_assert(sizeof(uintptr_t) == sizeof(void *), "uintptr_t is not void*"); 24 25 return backtrace(reinterpret_cast<void **>(TraceBuffer), Size); 26} 27 28// We don't need any custom handling for the Segv backtrace - the libc unwinder 29// has no problems with unwinding through a signal handler. Force inlining here 30// to avoid the additional frame. 31GWP_ASAN_ALWAYS_INLINE size_t SegvBacktrace(uintptr_t *TraceBuffer, size_t Size, 32 void * /*Context*/) { 33 return Backtrace(TraceBuffer, Size); 34} 35 36static void PrintBacktrace(uintptr_t *Trace, size_t TraceLength, 37 gwp_asan::Printf_t Printf) { 38 if (TraceLength == 0) { 39 Printf(" <not found (does your allocator support backtracing?)>\n\n"); 40 return; 41 } 42 43 char **BacktraceSymbols = 44 backtrace_symbols(reinterpret_cast<void **>(Trace), TraceLength); 45 46 for (size_t i = 0; i < TraceLength; ++i) { 47 if (!BacktraceSymbols) 48 Printf(" #%zu %p\n", i, Trace[i]); 49 else 50 Printf(" #%zu %s\n", i, BacktraceSymbols[i]); 51 } 52 53 Printf("\n"); 54 if (BacktraceSymbols) 55 free(BacktraceSymbols); 56} 57} // anonymous namespace 58 59namespace gwp_asan { 60namespace backtrace { 61 62options::Backtrace_t getBacktraceFunction() { return Backtrace; } 63PrintBacktrace_t getPrintBacktraceFunction() { return PrintBacktrace; } 64SegvBacktrace_t getSegvBacktraceFunction() { return SegvBacktrace; } 65 66} // namespace backtrace 67} // namespace gwp_asan 68