1 //===-- sanitizer_suppressions.cc -----------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Suppression parsing/matching code.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "sanitizer_suppressions.h"
15 
16 #include "sanitizer_allocator_internal.h"
17 #include "sanitizer_common.h"
18 #include "sanitizer_flags.h"
19 #include "sanitizer_libc.h"
20 #include "sanitizer_placement_new.h"
21 
22 namespace __sanitizer {
23 
SuppressionContext(const char * suppression_types[],int suppression_types_num)24 SuppressionContext::SuppressionContext(const char *suppression_types[],
25                                        int suppression_types_num)
26     : suppression_types_(suppression_types),
27       suppression_types_num_(suppression_types_num), suppressions_(1),
28       can_parse_(true) {
29   CHECK_LE(suppression_types_num_, kMaxSuppressionTypes);
30   internal_memset(has_suppression_type_, 0, suppression_types_num_);
31 }
32 
GetPathAssumingFileIsRelativeToExec(const char * file_path,char * new_file_path,uptr new_file_path_size)33 static bool GetPathAssumingFileIsRelativeToExec(const char *file_path,
34                                                 /*out*/char *new_file_path,
35                                                 uptr new_file_path_size) {
36   InternalScopedString exec(kMaxPathLength);
37   if (ReadBinaryName(exec.data(), exec.size())) {
38     const char *file_name_pos = StripModuleName(exec.data());
39     uptr path_to_exec_len = file_name_pos - exec.data();
40     internal_strncat(new_file_path, exec.data(),
41                      Min(path_to_exec_len, new_file_path_size - 1));
42     internal_strncat(new_file_path, file_path,
43                      new_file_path_size - internal_strlen(new_file_path) - 1);
44     return true;
45   }
46   return false;
47 }
48 
ParseFromFile(const char * filename)49 void SuppressionContext::ParseFromFile(const char *filename) {
50   if (filename[0] == '\0')
51     return;
52 
53   // If we cannot find the file, check if its location is relative to
54   // the location of the executable.
55   InternalScopedString new_file_path(kMaxPathLength);
56   if (!FileExists(filename) && !IsAbsolutePath(filename) &&
57       GetPathAssumingFileIsRelativeToExec(filename, new_file_path.data(),
58                                           new_file_path.size())) {
59     filename = new_file_path.data();
60   }
61 
62   // Read the file.
63   char *file_contents;
64   uptr buffer_size;
65   const uptr max_len = 1 << 26;
66   uptr contents_size =
67     ReadFileToBuffer(filename, &file_contents, &buffer_size, max_len);
68   VPrintf(1, "%s: reading suppressions file at %s\n",
69           SanitizerToolName, filename);
70 
71   if (contents_size == 0) {
72     Printf("%s: failed to read suppressions file '%s'\n", SanitizerToolName,
73            filename);
74     Die();
75   }
76 
77   Parse(file_contents);
78 }
79 
Match(const char * str,const char * type,Suppression ** s)80 bool SuppressionContext::Match(const char *str, const char *type,
81                                Suppression **s) {
82   can_parse_ = false;
83   if (!HasSuppressionType(type))
84     return false;
85   for (uptr i = 0; i < suppressions_.size(); i++) {
86     Suppression &cur = suppressions_[i];
87     if (0 == internal_strcmp(cur.type, type) && TemplateMatch(cur.templ, str)) {
88       *s = &cur;
89       return true;
90     }
91   }
92   return false;
93 }
94 
StripPrefix(const char * str,const char * prefix)95 static const char *StripPrefix(const char *str, const char *prefix) {
96   while (str && *str == *prefix) {
97     str++;
98     prefix++;
99   }
100   if (!*prefix)
101     return str;
102   return 0;
103 }
104 
Parse(const char * str)105 void SuppressionContext::Parse(const char *str) {
106   // Context must not mutate once Match has been called.
107   CHECK(can_parse_);
108   const char *line = str;
109   while (line) {
110     while (line[0] == ' ' || line[0] == '\t')
111       line++;
112     const char *end = internal_strchr(line, '\n');
113     if (end == 0)
114       end = line + internal_strlen(line);
115     if (line != end && line[0] != '#') {
116       const char *end2 = end;
117       while (line != end2 && (end2[-1] == ' ' || end2[-1] == '\t'))
118         end2--;
119       int type;
120       for (type = 0; type < suppression_types_num_; type++) {
121         const char *next_char = StripPrefix(line, suppression_types_[type]);
122         if (next_char && *next_char == ':') {
123           line = ++next_char;
124           break;
125         }
126       }
127       if (type == suppression_types_num_) {
128         Printf("%s: failed to parse suppressions\n", SanitizerToolName);
129         Die();
130       }
131       Suppression s;
132       s.type = suppression_types_[type];
133       s.templ = (char*)InternalAlloc(end2 - line + 1);
134       internal_memcpy(s.templ, line, end2 - line);
135       s.templ[end2 - line] = 0;
136       s.hit_count = 0;
137       s.weight = 0;
138       suppressions_.push_back(s);
139       has_suppression_type_[type] = true;
140     }
141     if (end[0] == 0)
142       break;
143     line = end + 1;
144   }
145 }
146 
SuppressionCount() const147 uptr SuppressionContext::SuppressionCount() const {
148   return suppressions_.size();
149 }
150 
HasSuppressionType(const char * type) const151 bool SuppressionContext::HasSuppressionType(const char *type) const {
152   for (int i = 0; i < suppression_types_num_; i++) {
153     if (0 == internal_strcmp(type, suppression_types_[i]))
154       return has_suppression_type_[i];
155   }
156   return false;
157 }
158 
SuppressionAt(uptr i) const159 const Suppression *SuppressionContext::SuppressionAt(uptr i) const {
160   CHECK_LT(i, suppressions_.size());
161   return &suppressions_[i];
162 }
163 
GetMatched(InternalMmapVector<Suppression * > * matched)164 void SuppressionContext::GetMatched(
165     InternalMmapVector<Suppression *> *matched) {
166   for (uptr i = 0; i < suppressions_.size(); i++)
167     if (suppressions_[i].hit_count)
168       matched->push_back(&suppressions_[i]);
169 }
170 
171 }  // namespace __sanitizer
172