1 //===-- sanitizer_procmaps_linux.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 // Information about the process mappings (Linux-specific parts).
11 //===----------------------------------------------------------------------===//
12
13 #include "sanitizer_platform.h"
14 #if SANITIZER_LINUX
15 #include "sanitizer_common.h"
16 #include "sanitizer_procmaps.h"
17
18 namespace __sanitizer {
19
ReadProcMaps(ProcSelfMapsBuff * proc_maps)20 void ReadProcMaps(ProcSelfMapsBuff *proc_maps) {
21 if (!ReadFileToBuffer("/proc/self/maps", &proc_maps->data,
22 &proc_maps->mmaped_size, &proc_maps->len)) {
23 proc_maps->data = nullptr;
24 proc_maps->mmaped_size = 0;
25 proc_maps->len = 0;
26 }
27 }
28
IsOneOf(char c,char c1,char c2)29 static bool IsOneOf(char c, char c1, char c2) {
30 return c == c1 || c == c2;
31 }
32
Next(MemoryMappedSegment * segment)33 bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
34 if (Error()) return false; // simulate empty maps
35 char *last = data_.proc_self_maps.data + data_.proc_self_maps.len;
36 if (data_.current >= last) return false;
37 char *next_line =
38 (char *)internal_memchr(data_.current, '\n', last - data_.current);
39 if (next_line == 0)
40 next_line = last;
41 // Example: 08048000-08056000 r-xp 00000000 03:0c 64593 /foo/bar
42 segment->start = ParseHex(&data_.current);
43 CHECK_EQ(*data_.current++, '-');
44 segment->end = ParseHex(&data_.current);
45 CHECK_EQ(*data_.current++, ' ');
46 CHECK(IsOneOf(*data_.current, '-', 'r'));
47 segment->protection = 0;
48 if (*data_.current++ == 'r') segment->protection |= kProtectionRead;
49 CHECK(IsOneOf(*data_.current, '-', 'w'));
50 if (*data_.current++ == 'w') segment->protection |= kProtectionWrite;
51 CHECK(IsOneOf(*data_.current, '-', 'x'));
52 if (*data_.current++ == 'x') segment->protection |= kProtectionExecute;
53 CHECK(IsOneOf(*data_.current, 's', 'p'));
54 if (*data_.current++ == 's') segment->protection |= kProtectionShared;
55 CHECK_EQ(*data_.current++, ' ');
56 segment->offset = ParseHex(&data_.current);
57 CHECK_EQ(*data_.current++, ' ');
58 ParseHex(&data_.current);
59 CHECK_EQ(*data_.current++, ':');
60 ParseHex(&data_.current);
61 CHECK_EQ(*data_.current++, ' ');
62 while (IsDecimal(*data_.current)) data_.current++;
63 // Qemu may lack the trailing space.
64 // https://github.com/google/sanitizers/issues/160
65 // CHECK_EQ(*data_.current++, ' ');
66 // Skip spaces.
67 while (data_.current < next_line && *data_.current == ' ') data_.current++;
68 // Fill in the filename.
69 if (segment->filename) {
70 uptr len =
71 Min((uptr)(next_line - data_.current), segment->filename_size - 1);
72 internal_strncpy(segment->filename, data_.current, len);
73 segment->filename[len] = 0;
74 }
75
76 data_.current = next_line + 1;
77 return true;
78 }
79
80 } // namespace __sanitizer
81
82 #endif // SANITIZER_LINUX
83