1 // Copyright (c) 2010 Google Inc.
2 // All rights reserved.
3 //
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are
6 // met:
7 //
8 // * Redistributions of source code must retain the above copyright
9 // notice, this list of conditions and the following disclaimer.
10 // * Redistributions in binary form must reproduce the above
11 // copyright notice, this list of conditions and the following disclaimer
12 // in the documentation and/or other materials provided with the
13 // distribution.
14 // * Neither the name of Google Inc. nor the names of its
15 // contributors may be used to endorse or promote products derived from
16 // this software without specific prior written permission.
17 //
18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30 // Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>
31
32 // dwarf_line_to_module.cc: Implementation of DwarfLineToModule class.
33 // See dwarf_line_to_module.h for details.
34
35 #include <stdio.h>
36
37 #include <string>
38
39 #include "common/dwarf_line_to_module.h"
40 #include "common/using_std_string.h"
41
42 // Trying to support Windows paths in a reasonable way adds a lot of
43 // variations to test; it would be better to just put off dealing with
44 // it until we actually have to deal with DWARF on Windows.
45
46 // Return true if PATH is an absolute path, false if it is relative.
PathIsAbsolute(const string & path)47 static bool PathIsAbsolute(const string &path) {
48 return (path.size() >= 1 && path[0] == '/');
49 }
50
HasTrailingSlash(const string & path)51 static bool HasTrailingSlash(const string &path) {
52 return (path.size() >= 1 && path[path.size() - 1] == '/');
53 }
54
55 // If PATH is an absolute path, return PATH. If PATH is a relative path,
56 // treat it as relative to BASE and return the combined path.
ExpandPath(const string & path,const string & base)57 static string ExpandPath(const string &path,
58 const string &base) {
59 if (PathIsAbsolute(path) || base.empty())
60 return path;
61 return base + (HasTrailingSlash(base) ? "" : "/") + path;
62 }
63
64 namespace google_breakpad {
65
DefineDir(const string & name,uint32_t dir_num)66 void DwarfLineToModule::DefineDir(const string &name, uint32_t dir_num) {
67 // Directory number zero is reserved to mean the compilation
68 // directory. Silently ignore attempts to redefine it.
69 if (dir_num != 0)
70 directories_[dir_num] = ExpandPath(name, compilation_dir_);
71 }
72
DefineFile(const string & name,int32_t file_num,uint32_t dir_num,uint64_t mod_time,uint64_t length)73 void DwarfLineToModule::DefineFile(const string &name, int32_t file_num,
74 uint32_t dir_num, uint64_t mod_time,
75 uint64_t length) {
76 if (file_num == -1)
77 file_num = ++highest_file_number_;
78 else if (file_num > highest_file_number_)
79 highest_file_number_ = file_num;
80
81 string dir_name;
82 if (dir_num == 0) {
83 // Directory number zero is the compilation directory, and is stored as
84 // an attribute on the compilation unit, rather than in the program table.
85 dir_name = compilation_dir_;
86 } else {
87 DirectoryTable::const_iterator directory_it = directories_.find(dir_num);
88 if (directory_it != directories_.end()) {
89 dir_name = directory_it->second;
90 } else {
91 if (!warned_bad_directory_number_) {
92 fprintf(stderr, "warning: DWARF line number data refers to undefined"
93 " directory numbers\n");
94 warned_bad_directory_number_ = true;
95 }
96 }
97 }
98
99 string full_name = ExpandPath(name, dir_name);
100
101 // Find a Module::File object of the given name, and add it to the
102 // file table.
103 files_[file_num] = module_->FindFile(full_name);
104 }
105
AddLine(uint64_t address,uint64_t length,uint32_t file_num,uint32_t line_num,uint32_t column_num)106 void DwarfLineToModule::AddLine(uint64_t address, uint64_t length,
107 uint32_t file_num, uint32_t line_num,
108 uint32_t column_num) {
109 if (length == 0)
110 return;
111
112 // Clip lines not to extend beyond the end of the address space.
113 if (address + length < address)
114 length = -address;
115
116 // Should we omit this line? (See the comments for omitted_line_end_.)
117 if (address == 0 || address == omitted_line_end_) {
118 omitted_line_end_ = address + length;
119 return;
120 } else {
121 omitted_line_end_ = 0;
122 }
123
124 // Find the source file being referred to.
125 Module::File *file = files_[file_num];
126 if (!file) {
127 if (!warned_bad_file_number_) {
128 fprintf(stderr, "warning: DWARF line number data refers to "
129 "undefined file numbers\n");
130 warned_bad_file_number_ = true;
131 }
132 return;
133 }
134 Module::Line line;
135 line.address = address;
136 // We set the size when we get the next line or the EndSequence call.
137 line.size = length;
138 line.file = file;
139 line.number = line_num;
140 lines_->push_back(line);
141 }
142
143 } // namespace google_breakpad
144