1 // Copyright 2010 Google LLC
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 LLC 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 // Original author: Jim Blandy <[email protected]> <[email protected]>
30
31 // dwarf_line_to_module.cc: Implementation of DwarfLineToModule class.
32 // See dwarf_line_to_module.h for details.
33
34 #ifdef HAVE_CONFIG_H
35 #include <config.h> // Must come first
36 #endif
37
38 #include <stdio.h>
39
40 #include <string>
41
42 #include "common/dwarf_line_to_module.h"
43 #include "common/using_std_string.h"
44
45 // Trying to support Windows paths in a reasonable way adds a lot of
46 // variations to test; it would be better to just put off dealing with
47 // it until we actually have to deal with DWARF on Windows.
48
49 // Return true if PATH is an absolute path, false if it is relative.
PathIsAbsolute(const string & path)50 static bool PathIsAbsolute(const string& path) {
51 return (path.size() >= 1 && path[0] == '/');
52 }
53
HasTrailingSlash(const string & path)54 static bool HasTrailingSlash(const string& path) {
55 return (path.size() >= 1 && path[path.size() - 1] == '/');
56 }
57
58 // If PATH is an absolute path, return PATH. If PATH is a relative path,
59 // treat it as relative to BASE and return the combined path.
ExpandPath(const string & path,const string & base)60 static string ExpandPath(const string& path,
61 const string& base) {
62 if (PathIsAbsolute(path) || base.empty())
63 return path;
64 return base + (HasTrailingSlash(base) ? "" : "/") + path;
65 }
66
67 namespace google_breakpad {
68
DefineDir(const string & name,uint32_t dir_num)69 void DwarfLineToModule::DefineDir(const string& name, uint32_t dir_num) {
70 // Directory number zero is reserved to mean the compilation
71 // directory. Silently ignore attempts to redefine it.
72 if (dir_num != 0)
73 directories_[dir_num] = ExpandPath(name, compilation_dir_);
74 }
75
DefineFile(const string & name,int32_t file_num,uint32_t dir_num,uint64_t mod_time,uint64_t length)76 void DwarfLineToModule::DefineFile(const string& name, int32_t file_num,
77 uint32_t dir_num, uint64_t mod_time,
78 uint64_t length) {
79 if (file_num == -1)
80 file_num = ++highest_file_number_;
81 else if (file_num > highest_file_number_)
82 highest_file_number_ = file_num;
83
84 string dir_name;
85 if (dir_num == 0) {
86 // Directory number zero is the compilation directory, and is stored as
87 // an attribute on the compilation unit, rather than in the program table.
88 dir_name = compilation_dir_;
89 } else {
90 DirectoryTable::const_iterator directory_it = directories_.find(dir_num);
91 if (directory_it != directories_.end()) {
92 dir_name = directory_it->second;
93 } else {
94 if (!warned_bad_directory_number_) {
95 fprintf(stderr, "warning: DWARF line number data refers to undefined"
96 " directory numbers\n");
97 warned_bad_directory_number_ = true;
98 }
99 }
100 }
101
102 string full_name = ExpandPath(name, dir_name);
103
104 // Find a Module::File object of the given name, and add it to the
105 // file table.
106 (*files_)[file_num] = module_->FindFile(full_name);
107 }
108
AddLine(uint64_t address,uint64_t length,uint32_t file_num,uint32_t line_num,uint32_t column_num)109 void DwarfLineToModule::AddLine(uint64_t address, uint64_t length,
110 uint32_t file_num, uint32_t line_num,
111 uint32_t column_num) {
112 if (length == 0)
113 return;
114
115 // Clip lines not to extend beyond the end of the address space.
116 if (address + length < address)
117 length = -address;
118
119 // Should we omit this line? (See the comments for omitted_line_end_.)
120 if (address == 0 || address == omitted_line_end_) {
121 omitted_line_end_ = address + length;
122 return;
123 } else {
124 omitted_line_end_ = 0;
125 }
126
127 // Find the source file being referred to.
128 Module::File *file = (*files_)[file_num];
129 if (!file) {
130 if (!warned_bad_file_number_) {
131 fprintf(stderr, "warning: DWARF line number data refers to "
132 "undefined file numbers\n");
133 warned_bad_file_number_ = true;
134 }
135 return;
136 }
137 Module::Line line;
138 line.address = address;
139 // We set the size when we get the next line or the EndSequence call.
140 line.size = length;
141 line.file = file;
142 line.number = line_num;
143 lines_->push_back(line);
144 }
145
146 } // namespace google_breakpad
147