don't use glibc-specific execinfo.h on uclibc builds

base/debug/stack_trace_posix.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/debug/stack_trace.h"
 
 #include <errno.h>
+
+#if !defined(__UCLIBC__)

[Mark Mentovai, 2014/04/08 15:56:28]

Why is this still up here? Can you move it down with the other conditional
#includes?

[Mostyn Bramley-Moore, 2014/04/08 16:16:39]

I wasn't sure if libc++ builds need this, and if they define __GLIBCXX__ or not.
 I suspect no on both counts.  I'll move it back down.

 #include <execinfo.h>
+#endif
+
 #include <fcntl.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/param.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
 
 #include <map>
 #include <ostream>
 #include <string>
 #include <vector>
 
-#if defined(__GLIBCXX__)
+#if defined(__GLIBCXX__) && !defined(__UCLIBC__)
 #include <cxxabi.h>
 #endif
 
 #if defined(OS_MACOSX)
 #include <AvailabilityMacros.h>
 #endif
 
 #include "base/basictypes.h"
 #include "base/debug/debugger.h"
 #include "base/debug/proc_maps_linux.h"
@@ skipping 30 matching lines @@
 #if !defined(USE_SYMBOLIZE)
 // Demangles C++ symbols in the given text. Example:
 //
 // "out/Debug/base_unittests(_ZN10StackTraceC1Ev+0x20) [0x817778c]"
 // =>
 // "out/Debug/base_unittests(StackTrace::StackTrace()+0x20) [0x817778c]"
 void DemangleSymbols(std::string* text) {
   // Note: code in this function is NOT async-signal safe (std::string uses
   // malloc internally).
 
-#if defined(__GLIBCXX__)
+#if defined(__GLIBCXX__) && !defined(__UCLIBC__)
 
   std::string::size_type search_from = 0;
   while (search_from < text->size()) {
     // Look for the start of a mangled symbol, from search_from.
     std::string::size_type mangled_start =
         text->find(kMangledSymbolPrefix, search_from);
     if (mangled_start == std::string::npos) {
       break;  // Mangled symbol not found.
     }
 
@@ skipping 16 matching lines @@
       // Insert the demangled symbol.
       text->insert(mangled_start, demangled_symbol.get());
       // Next time, we'll start right after the demangled symbol we inserted.
       search_from = mangled_start + strlen(demangled_symbol.get());
     } else {
       // Failed to demangle.  Retry after the "_Z" we just found.
       search_from = mangled_start + 2;
     }
   }
 
-#endif  // defined(__GLIBCXX__)
+#endif  // defined(__GLIBCXX__) && !defined(__UCLIBC__)
 }
 #endif  // !defined(USE_SYMBOLIZE)
 
 class BacktraceOutputHandler {
  public:
   virtual void HandleOutput(const char* output) = 0;
 
  protected:
   virtual ~BacktraceOutputHandler() {}
 };
@@ skipping 38 matching lines @@
     // Subtract by one as return address of function may be in the next
     // function when a function is annotated as noreturn.
     void* address = static_cast<char*>(trace[i]) - 1;
     if (google::Symbolize(address, buf, sizeof(buf)))
       handler->HandleOutput(buf);
     else
       handler->HandleOutput("<unknown>");
 
     handler->HandleOutput("\n");
   }
-#else
+#elif !defined(__UCLIBC__)
   bool printed = false;
 
   // Below part is async-signal unsafe (uses malloc), so execute it only
   // when we are not executing the signal handler.
   if (in_signal_handler == 0) {
     scoped_ptr<char*, FreeDeleter>
         trace_symbols(backtrace_symbols(trace, size));
     if (trace_symbols.get()) {
       for (size_t i = 0; i < size; ++i) {
         std::string trace_symbol = trace_symbols.get()[i];
@@ skipping 91 matching lines @@
       PrintToStderr(" <unknown> ");
   }
   if (signal == SIGBUS || signal == SIGFPE ||
       signal == SIGILL || signal == SIGSEGV) {
     internal::itoa_r(reinterpret_cast<intptr_t>(info->si_addr),
                      buf, sizeof(buf), 16, 12);
     PrintToStderr(buf);
   }
   PrintToStderr("\n");
 
+#if !defined(__UCLIBC__)
   debug::StackTrace().Print();
+#endif
 
 #if defined(OS_LINUX)
 #if ARCH_CPU_X86_FAMILY
   ucontext_t* context = reinterpret_cast<ucontext_t*>(void_context);
   const struct {
     const char* label;
     greg_t value;
   } registers[] = {
 #if ARCH_CPU_32_BITS
     { "  gs: ", context->uc_mcontext.gregs[REG_GS] },
@@ skipping 438 matching lines @@
   success &= (sigaction(SIGSYS, &action, NULL) == 0);
 #endif  // !defined(OS_LINUX)
 
   return success;
 }
 
 StackTrace::StackTrace() {
   // NOTE: This code MUST be async-signal safe (it's used by in-process
   // stack dumping signal handler). NO malloc or stdio is allowed here.
 
+#if !defined(__UCLIBC__)
   // Though the backtrace API man page does not list any possible negative
   // return values, we take no chance.
   count_ = base::saturated_cast<size_t>(backtrace(trace_, arraysize(trace_)));
+#else
+  count_ = 0;
+#endif
 }
 
+#if !defined(__UCLIBC__)
 void StackTrace::Print() const {
   // NOTE: This code MUST be async-signal safe (it's used by in-process
   // stack dumping signal handler). NO malloc or stdio is allowed here.
 
   PrintBacktraceOutputHandler handler;
   ProcessBacktrace(trace_, count_, &handler);
 }
 
 void StackTrace::OutputToStream(std::ostream* os) const {
   StreamBacktraceOutputHandler handler(os);
   ProcessBacktrace(trace_, count_, &handler);
 }
+#endif
 
 namespace internal {
 
 // NOTE: code from sandbox/linux/seccomp-bpf/demo.cc.
 char *itoa_r(intptr_t i, char *buf, size_t sz, int base, size_t padding) {
   // Make sure we can write at least one NUL byte.
   size_t n = 1;
   if (n > sz)
     return NULL;
 
@@ skipping 48 matching lines @@
     *ptr = *start;
     *start++ = ch;
   }
   return buf;
 }
 
 }  // namespace internal
 
 }  // namespace debug
 }  // namespace base