stabs_to_module.h - mozsearch

// -*- mode: C++ -*-

// Copyright (c) 2010 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.

// Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>

// dump_stabs.h: Define the StabsToModule class, which receives

// STABS debugging information from a parser and adds it to a Breakpad

// symbol file.

#ifndef BREAKPAD_COMMON_STABS_TO_MODULE_H_

#define BREAKPAD_COMMON_STABS_TO_MODULE_H_

#include <stdint.h>

#include <string>

#include <vector>

#include "common/module.h"

#include "common/stabs_reader.h"

#include "common/using_std_string.h"

namespace google_breakpad {

using std::vector;

// A StabsToModule is a handler that receives parsed STABS debugging

// information from a StabsReader, and uses that to populate

// a Module. (All classes are in the google_breakpad namespace.) A

// Module represents the contents of a Breakpad symbol file, and knows

// how to write itself out as such. A StabsToModule thus acts as

// the bridge between STABS and Breakpad data.

// When processing Darwin Mach-O files, this also receives public linker

// symbols, like those found in system libraries.

class StabsToModule: public google_breakpad::StabsHandler {

 public:

  // Receive parsed debugging information from a StabsReader, and

  // store it all in MODULE.

  StabsToModule(Module *module) :

      module_(module),

      in_compilation_unit_(false),

      comp_unit_base_address_(0),

      current_function_(NULL),

      current_source_file_(NULL),

      current_source_file_name_(NULL) { }

  ~StabsToModule();

  // The standard StabsHandler virtual member functions.

  bool StartCompilationUnit(const char *name, uint64_t address,

                            const char *build_directory);

  bool EndCompilationUnit(uint64_t address);

  bool StartFunction(const string &name, uint64_t address);

  bool EndFunction(uint64_t address);

  bool Line(uint64_t address, const char *name, int number);

  bool Extern(const string &name, uint64_t address);

  void Warning(const char *format, ...);

  // Do any final processing necessary to make module_ contain all the

  // data provided by the STABS reader.

//

  // Because STABS does not provide reliable size information for

  // functions and lines, we need to make a pass over the data after

  // processing all the STABS to compute those sizes.  We take care of

  // that here.

  void Finalize();

 private:

  // An arbitrary, but very large, size to use for functions whose

  // size we can't compute properly.

  static const uint64_t kFallbackSize = 0x10000000;

  // The module we're contributing debugging info to.

  Module *module_;

  // The functions we've generated so far.  We don't add these to

  // module_ as we parse them.  Instead, we wait until we've computed

  // their ending address, and their lines' ending addresses.

//

  // We could just stick them in module_ from the outset, but if

  // module_ already contains data gathered from other debugging

  // formats, that would complicate the size computation.

  vector<Module::Function *> functions_;

  // Boundary addresses.  STABS doesn't necessarily supply sizes for

  // functions and lines, so we need to compute them ourselves by

  // finding the next object.

  vector<Module::Address> boundaries_;

  // True if we are currently within a compilation unit: we have gotten a

  // StartCompilationUnit call, but no matching EndCompilationUnit call

  // yet. We use this for sanity checks.

  bool in_compilation_unit_;

  // The base address of the current compilation unit.  We use this to

  // recognize functions we should omit from the symbol file.  (If you

  // know the details of why we omit these, please patch this

  // comment.)

  Module::Address comp_unit_base_address_;

  // The function we're currently contributing lines to.

  Module::Function *current_function_;

  // The last Module::File we got a line number in.

  Module::File *current_source_file_;

  // The pointer in the .stabstr section of the name that

  // current_source_file_ is built from.  This allows us to quickly

  // recognize when the current line is in the same file as the

  // previous one (which it usually is).

  const char *current_source_file_name_;

};

}  // namespace google_breakpad

#endif  // BREAKPAD_COMMON_STABS_TO_MODULE_H_