src/symbolize.h

// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
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// ---
// Author: Craig Silverstein

#ifndef TCMALLOC_SYMBOLIZE_H_
#define TCMALLOC_SYMBOLIZE_H_

#include "config.h"
#ifdef HAVE_STDINT_H
#include <stdint.h>  // for uintptr_t
#endif
#include <stddef.h>  // for NULL
#include <map>

using std::map;

// SymbolTable encapsulates the address operations necessary for stack trace
// symbolization. A common use-case is to Add() the addresses from one or
// several stack traces to a table, call Symbolize() once and use GetSymbol()
// to get the symbol names for pretty-printing the stack traces.
class SymbolTable {
 public:
  SymbolTable()
    : symbol_buffer_(NULL) {}
  ~SymbolTable() {
    delete[] symbol_buffer_;
  }

  // Adds an address to the table. This may overwrite a currently known symbol
  // name, so Add() should not generally be called after Symbolize().
  void Add(const void* addr);

  // Returns the symbol name for addr, if the given address was added before
  // the last successful call to Symbolize(). Otherwise may return an empty
  // c-string.
  const char* GetSymbol(const void* addr);

  // Obtains the symbol names for the addresses stored in the table and returns
  // the number of addresses actually symbolized.
  int Symbolize();

 private:
  typedef map<const void*, const char*> SymbolMap;

  // An average size of memory allocated for a stack trace symbol.
  static const int kSymbolSize = 1024;

  // Map from addresses to symbol names.
  SymbolMap symbolization_table_;

  // Pointer to the buffer that stores the symbol names.
  char *symbol_buffer_;
};

#endif  // TCMALLOC_SYMBOLIZE_H_