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 dir_num)65 void CULineInfoHandler::DefineDir(const string& name, uint32 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 dir_num,uint64 mod_time,uint64 length)71 void CULineInfoHandler::DefineFile(const string& name,
72 int32 file_num, uint32 dir_num,
73 uint64 mod_time, uint64 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 address,uint64 length,uint32 file_num,uint32 line_num,uint32 column_num)96 void CULineInfoHandler::AddLine(uint64 address, uint64 length, uint32 file_num,
97 uint32 line_num, uint32 column_num) {
98 if (file_num < files_->size()) {
99 linemap_->insert(
100 std::make_pair(address,
101 std::make_pair(files_->at(file_num).name.c_str(),
102 line_num)));
103
104 if (address < files_->at(file_num).lowpc) {
105 files_->at(file_num).lowpc = address;
106 }
107 } else {
108 fprintf(stderr, "error in AddLine");
109 }
110 }
111
StartCompilationUnit(uint64 offset,uint8 address_size,uint8 offset_size,uint64 cu_length,uint8 dwarf_version)112 bool CUFunctionInfoHandler::StartCompilationUnit(uint64 offset,
113 uint8 address_size,
114 uint8 offset_size,
115 uint64 cu_length,
116 uint8 dwarf_version) {
117 current_compilation_unit_offset_ = offset;
118 return true;
119 }
120
121
122 // For function info, we only care about subprograms and inlined
123 // subroutines. For line info, the DW_AT_stmt_list lives in the
124 // compile unit tag.
125
StartDIE(uint64 offset,enum DwarfTag tag)126 bool CUFunctionInfoHandler::StartDIE(uint64 offset, enum DwarfTag tag) {
127 switch (tag) {
128 case DW_TAG_subprogram:
129 case DW_TAG_inlined_subroutine: {
130 current_function_info_ = new FunctionInfo;
131 current_function_info_->lowpc = current_function_info_->highpc = 0;
132 current_function_info_->name = "";
133 current_function_info_->line = 0;
134 current_function_info_->file = "";
135 offset_to_funcinfo_->insert(std::make_pair(offset,
136 current_function_info_));
137 };
138 // FALLTHROUGH
139 case DW_TAG_compile_unit:
140 return true;
141 default:
142 return false;
143 }
144 return false;
145 }
146
147 // Only care about the name attribute for functions
148
ProcessAttributeString(uint64 offset,enum DwarfAttribute attr,enum DwarfForm form,const string & data)149 void CUFunctionInfoHandler::ProcessAttributeString(uint64 offset,
150 enum DwarfAttribute attr,
151 enum DwarfForm form,
152 const string &data) {
153 if (current_function_info_) {
154 if (attr == DW_AT_name)
155 current_function_info_->name = data;
156 else if (attr == DW_AT_MIPS_linkage_name)
157 current_function_info_->mangled_name = data;
158 }
159 }
160
ProcessAttributeUnsigned(uint64 offset,enum DwarfAttribute attr,enum DwarfForm form,uint64 data)161 void CUFunctionInfoHandler::ProcessAttributeUnsigned(uint64 offset,
162 enum DwarfAttribute attr,
163 enum DwarfForm form,
164 uint64 data) {
165 if (attr == DW_AT_stmt_list) {
166 SectionMap::const_iterator iter = sections_.find("__debug_line");
167 assert(iter != sections_.end());
168
169 scoped_ptr<LineInfo> lireader(new LineInfo(iter->second.first + data,
170 iter->second.second - data,
171 reader_, linehandler_));
172 lireader->Start();
173 } else if (current_function_info_) {
174 switch (attr) {
175 case DW_AT_low_pc:
176 current_function_info_->lowpc = data;
177 break;
178 case DW_AT_high_pc:
179 current_function_info_->highpc = data;
180 break;
181 case DW_AT_decl_line:
182 current_function_info_->line = data;
183 break;
184 case DW_AT_decl_file:
185 current_function_info_->file = files_->at(data).name;
186 break;
187 default:
188 break;
189 }
190 }
191 }
192
ProcessAttributeReference(uint64 offset,enum DwarfAttribute attr,enum DwarfForm form,uint64 data)193 void CUFunctionInfoHandler::ProcessAttributeReference(uint64 offset,
194 enum DwarfAttribute attr,
195 enum DwarfForm form,
196 uint64 data) {
197 if (current_function_info_) {
198 switch (attr) {
199 case DW_AT_specification: {
200 // Some functions have a "specification" attribute
201 // which means they were defined elsewhere. The name
202 // attribute is not repeated, and must be taken from
203 // the specification DIE. Here we'll assume that
204 // any DIE referenced in this manner will already have
205 // been seen, but that's not really required by the spec.
206 FunctionMap::iterator iter = offset_to_funcinfo_->find(data);
207 if (iter != offset_to_funcinfo_->end()) {
208 current_function_info_->name = iter->second->name;
209 current_function_info_->mangled_name = iter->second->mangled_name;
210 } else {
211 // If you hit this, this code probably needs to be rewritten.
212 fprintf(stderr,
213 "Error: DW_AT_specification was seen before the referenced "
214 "DIE! (Looking for DIE at offset %08llx, in DIE at "
215 "offset %08llx)\n", data, offset);
216 }
217 break;
218 }
219 default:
220 break;
221 }
222 }
223 }
224
EndDIE(uint64 offset)225 void CUFunctionInfoHandler::EndDIE(uint64 offset) {
226 if (current_function_info_ && current_function_info_->lowpc)
227 address_to_funcinfo_->insert(std::make_pair(current_function_info_->lowpc,
228 current_function_info_));
229 }
230
231 } // namespace dwarf2reader
232