1 // Copyright (c) 2010 Google Inc. All Rights Reserved.
2 //
3 // Redistribution and use in source and binary forms, with or without
4 // modification, are permitted provided that the following conditions are
5 // met:
6 //
7 // * Redistributions of source code must retain the above copyright
8 // notice, this list of conditions and the following disclaimer.
9 // * Redistributions in binary form must reproduce the above
10 // copyright notice, this list of conditions and the following disclaimer
11 // in the documentation and/or other materials provided with the
12 // distribution.
13 // * Neither the name of Google Inc. nor the names of its
14 // contributors may be used to endorse or promote products derived from
15 // this software without specific prior written permission.
16 //
17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29 // This is a client for the dwarf2reader to extract function and line
30 // information from the debug info.
31
32 #include <assert.h>
33 #include <limits.h>
34 #include <stdio.h>
35
36 #include <map>
37 #include <queue>
38 #include <vector>
39
40 #include "common/dwarf/functioninfo.h"
41 #include "common/dwarf/bytereader.h"
42 #include "common/scoped_ptr.h"
43 #include "common/using_std_string.h"
44
45 using google_breakpad::scoped_ptr;
46
47 namespace dwarf2reader {
48
CULineInfoHandler(std::vector<SourceFileInfo> * files,std::vector<string> * dirs,LineMap * linemap)49 CULineInfoHandler::CULineInfoHandler(std::vector<SourceFileInfo>* files,
50 std::vector<string>* dirs,
51 LineMap* linemap):linemap_(linemap),
52 files_(files),
53 dirs_(dirs) {
54 // The dirs and files are 1 indexed, so just make sure we put
55 // nothing in the 0 vector.
56 assert(dirs->size() == 0);
57 assert(files->size() == 0);
58 dirs->push_back("");
59 SourceFileInfo s;
60 s.name = "";
61 s.lowpc = ULLONG_MAX;
62 files->push_back(s);
63 }
64
DefineDir(const string & name,uint32_t dir_num)65 void CULineInfoHandler::DefineDir(const string& name, uint32_t dir_num) {
66 // These should never come out of order, actually
67 assert(dir_num == dirs_->size());
68 dirs_->push_back(name);
69 }
70
DefineFile(const string & name,int32 file_num,uint32_t dir_num,uint64_t mod_time,uint64_t length)71 void CULineInfoHandler::DefineFile(const string& name,
72 int32 file_num, uint32_t dir_num,
73 uint64_t mod_time, uint64_t length) {
74 assert(dir_num >= 0);
75 assert(dir_num < dirs_->size());
76
77 // These should never come out of order, actually.
78 if (file_num == (int32)files_->size() || file_num == -1) {
79 string dir = dirs_->at(dir_num);
80
81 SourceFileInfo s;
82 s.lowpc = ULLONG_MAX;
83
84 if (dir == "") {
85 s.name = name;
86 } else {
87 s.name = dir + "/" + name;
88 }
89
90 files_->push_back(s);
91 } else {
92 fprintf(stderr, "error in DefineFile");
93 }
94 }
95
AddLine(uint64_t address,uint64_t length,uint32_t file_num,uint32_t line_num,uint32_t column_num)96 void CULineInfoHandler::AddLine(uint64_t address, uint64_t length,
97 uint32_t file_num, uint32_t line_num,
98 uint32_t column_num) {
99 if (file_num < files_->size()) {
100 linemap_->insert(
101 std::make_pair(address,
102 std::make_pair(files_->at(file_num).name.c_str(),
103 line_num)));
104
105 if (address < files_->at(file_num).lowpc) {
106 files_->at(file_num).lowpc = address;
107 }
108 } else {
109 fprintf(stderr, "error in AddLine");
110 }
111 }
112
StartCompilationUnit(uint64_t offset,uint8_t address_size,uint8_t offset_size,uint64_t cu_length,uint8_t dwarf_version)113 bool CUFunctionInfoHandler::StartCompilationUnit(uint64_t offset,
114 uint8_t address_size,
115 uint8_t offset_size,
116 uint64_t cu_length,
117 uint8_t dwarf_version) {
118 current_compilation_unit_offset_ = offset;
119 return true;
120 }
121
122
123 // For function info, we only care about subprograms and inlined
124 // subroutines. For line info, the DW_AT_stmt_list lives in the
125 // compile unit tag.
126
StartDIE(uint64_t offset,enum DwarfTag tag)127 bool CUFunctionInfoHandler::StartDIE(uint64_t offset, enum DwarfTag tag) {
128 switch (tag) {
129 case DW_TAG_subprogram:
130 case DW_TAG_inlined_subroutine: {
131 current_function_info_ = new FunctionInfo;
132 current_function_info_->lowpc = current_function_info_->highpc = 0;
133 current_function_info_->name = "";
134 current_function_info_->line = 0;
135 current_function_info_->file = "";
136 offset_to_funcinfo_->insert(std::make_pair(offset,
137 current_function_info_));
138 };
139 // FALLTHROUGH
140 case DW_TAG_compile_unit:
141 return true;
142 default:
143 return false;
144 }
145 return false;
146 }
147
148 // Only care about the name attribute for functions
149
ProcessAttributeString(uint64_t offset,enum DwarfAttribute attr,enum DwarfForm form,const string & data)150 void CUFunctionInfoHandler::ProcessAttributeString(uint64_t offset,
151 enum DwarfAttribute attr,
152 enum DwarfForm form,
153 const string &data) {
154 if (current_function_info_) {
155 if (attr == DW_AT_name)
156 current_function_info_->name = data;
157 else if (attr == DW_AT_MIPS_linkage_name)
158 current_function_info_->mangled_name = data;
159 }
160 }
161
ProcessAttributeUnsigned(uint64_t offset,enum DwarfAttribute attr,enum DwarfForm form,uint64_t data)162 void CUFunctionInfoHandler::ProcessAttributeUnsigned(uint64_t offset,
163 enum DwarfAttribute attr,
164 enum DwarfForm form,
165 uint64_t data) {
166 if (attr == DW_AT_stmt_list) {
167 SectionMap::const_iterator iter = sections_.find("__debug_line");
168 assert(iter != sections_.end());
169
170 scoped_ptr<LineInfo> lireader(new LineInfo(iter->second.first + data,
171 iter->second.second - data,
172 reader_, linehandler_));
173 lireader->Start();
174 } else if (current_function_info_) {
175 switch (attr) {
176 case DW_AT_low_pc:
177 current_function_info_->lowpc = data;
178 break;
179 case DW_AT_high_pc:
180 current_function_info_->highpc = data;
181 break;
182 case DW_AT_decl_line:
183 current_function_info_->line = data;
184 break;
185 case DW_AT_decl_file:
186 current_function_info_->file = files_->at(data).name;
187 break;
188 case DW_AT_ranges:
189 current_function_info_->ranges = data;
190 break;
191 default:
192 break;
193 }
194 }
195 }
196
ProcessAttributeReference(uint64_t offset,enum DwarfAttribute attr,enum DwarfForm form,uint64_t data)197 void CUFunctionInfoHandler::ProcessAttributeReference(uint64_t offset,
198 enum DwarfAttribute attr,
199 enum DwarfForm form,
200 uint64_t data) {
201 if (current_function_info_) {
202 switch (attr) {
203 case DW_AT_specification: {
204 // Some functions have a "specification" attribute
205 // which means they were defined elsewhere. The name
206 // attribute is not repeated, and must be taken from
207 // the specification DIE. Here we'll assume that
208 // any DIE referenced in this manner will already have
209 // been seen, but that's not really required by the spec.
210 FunctionMap::iterator iter = offset_to_funcinfo_->find(data);
211 if (iter != offset_to_funcinfo_->end()) {
212 current_function_info_->name = iter->second->name;
213 current_function_info_->mangled_name = iter->second->mangled_name;
214 } else {
215 // If you hit this, this code probably needs to be rewritten.
216 fprintf(stderr,
217 "Error: DW_AT_specification was seen before the referenced "
218 "DIE! (Looking for DIE at offset %08llx, in DIE at "
219 "offset %08llx)\n", data, offset);
220 }
221 break;
222 }
223 default:
224 break;
225 }
226 }
227 }
228
EndDIE(uint64_t offset)229 void CUFunctionInfoHandler::EndDIE(uint64_t offset) {
230 if (current_function_info_ && current_function_info_->lowpc)
231 address_to_funcinfo_->insert(std::make_pair(current_function_info_->lowpc,
232 current_function_info_));
233 }
234
235 } // namespace dwarf2reader
236