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29
30// Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>
31
32// dump_stabs.cc --- implement the StabsToModule class.
33
34#include <assert.h>
35#include <cxxabi.h>
36#include <stdarg.h>
37#include <stdio.h>
38
39#include <algorithm>
40
41#include "common/stabs_to_module.h"
42#include "common/using_std_string.h"
43
44namespace google_breakpad {
45
46// Demangle using abi call.
47// Older GCC may not support it.
48static string Demangle(const string &mangled) {
49  int status = 0;
50  char *demangled = abi::__cxa_demangle(mangled.c_str(), NULL, NULL, &status);
51  if (status == 0 && demangled != NULL) {
52    string str(demangled);
53    free(demangled);
54    return str;
55  }
56  return string(mangled);
57}
58
59StabsToModule::~StabsToModule() {
60  // Free any functions we've accumulated but not added to the module.
61  for (vector<Module::Function *>::const_iterator func_it = functions_.begin();
62       func_it != functions_.end(); func_it++)
63    delete *func_it;
64  // Free any function that we're currently within.
65  delete current_function_;
66}
67
68bool StabsToModule::StartCompilationUnit(const char *name, uint64_t address,
69                                         const char *build_directory) {
70  assert(!in_compilation_unit_);
71  in_compilation_unit_ = true;
72  current_source_file_name_ = name;
73  current_source_file_ = module_->FindFile(name);
74  comp_unit_base_address_ = address;
75  boundaries_.push_back(static_cast<Module::Address>(address));
76  return true;
77}
78
79bool StabsToModule::EndCompilationUnit(uint64_t address) {
80  assert(in_compilation_unit_);
81  in_compilation_unit_ = false;
82  comp_unit_base_address_ = 0;
83  current_source_file_ = NULL;
84  current_source_file_name_ = NULL;
85  if (address)
86    boundaries_.push_back(static_cast<Module::Address>(address));
87  return true;
88}
89
90bool StabsToModule::StartFunction(const string &name,
91                                  uint64_t address) {
92  assert(!current_function_);
93  Module::Function *f = new Module::Function(Demangle(name), address);
94  f->size = 0;           // We compute this in StabsToModule::Finalize().
95  f->parameter_size = 0; // We don't provide this information.
96  current_function_ = f;
97  boundaries_.push_back(static_cast<Module::Address>(address));
98  return true;
99}
100
101bool StabsToModule::EndFunction(uint64_t address) {
102  assert(current_function_);
103  // Functions in this compilation unit should have address bigger
104  // than the compilation unit's starting address.  There may be a lot
105  // of duplicated entries for functions in the STABS data. We will
106  // count on the Module to remove the duplicates.
107  if (current_function_->address >= comp_unit_base_address_)
108    functions_.push_back(current_function_);
109  else
110    delete current_function_;
111  current_function_ = NULL;
112  if (address)
113    boundaries_.push_back(static_cast<Module::Address>(address));
114  return true;
115}
116
117bool StabsToModule::Line(uint64_t address, const char *name, int number) {
118  assert(current_function_);
119  assert(current_source_file_);
120  if (name != current_source_file_name_) {
121    current_source_file_ = module_->FindFile(name);
122    current_source_file_name_ = name;
123  }
124  Module::Line line;
125  line.address = address;
126  line.size = 0;  // We compute this in StabsToModule::Finalize().
127  line.file = current_source_file_;
128  line.number = number;
129  current_function_->lines.push_back(line);
130  return true;
131}
132
133bool StabsToModule::Extern(const string &name, uint64_t address) {
134  Module::Extern *ext = new Module::Extern(address);
135  // Older libstdc++ demangle implementations can crash on unexpected
136  // input, so be careful about what gets passed in.
137  if (name.compare(0, 3, "__Z") == 0) {
138    ext->name = Demangle(name.substr(1));
139  } else if (name[0] == '_') {
140    ext->name = name.substr(1);
141  } else {
142    ext->name = name;
143  }
144  module_->AddExtern(ext);
145  return true;
146}
147
148void StabsToModule::Warning(const char *format, ...) {
149  va_list args;
150  va_start(args, format);
151  vfprintf(stderr, format, args);
152  va_end(args);
153}
154
155void StabsToModule::Finalize() {
156  // Sort our boundary list, so we can search it quickly.
157  sort(boundaries_.begin(), boundaries_.end());
158  // Sort all functions by address, just for neatness.
159  sort(functions_.begin(), functions_.end(),
160       Module::Function::CompareByAddress);
161
162  for (vector<Module::Function *>::const_iterator func_it = functions_.begin();
163       func_it != functions_.end();
164       func_it++) {
165    Module::Function *f = *func_it;
166    // Compute the function f's size.
167    vector<Module::Address>::const_iterator boundary
168        = std::upper_bound(boundaries_.begin(), boundaries_.end(), f->address);
169    if (boundary != boundaries_.end())
170      f->size = *boundary - f->address;
171    else
172      // If this is the last function in the module, and the STABS
173      // reader was unable to give us its ending address, then assign
174      // it a bogus, very large value.  This will happen at most once
175      // per module: since we've added all functions' addresses to the
176      // boundary table, only one can be the last.
177      f->size = kFallbackSize;
178
179    // Compute sizes for each of the function f's lines --- if it has any.
180    if (!f->lines.empty()) {
181      stable_sort(f->lines.begin(), f->lines.end(),
182                  Module::Line::CompareByAddress);
183      vector<Module::Line>::iterator last_line = f->lines.end() - 1;
184      for (vector<Module::Line>::iterator line_it = f->lines.begin();
185           line_it != last_line; line_it++)
186        line_it[0].size = line_it[1].address - line_it[0].address;
187      // Compute the size of the last line from f's end address.
188      last_line->size = (f->address + f->size) - last_line->address;
189    }
190  }
191  // Now that everything has a size, add our functions to the module, and
192  // dispose of our private list.
193  module_->AddFunctions(functions_.begin(), functions_.end());
194  functions_.clear();
195}
196
197} // namespace google_breakpad
198