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
18namespace __sanitizer {
19
20void 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
29static bool IsOneOf(char c, char c1, char c2) {
30  return c == c1 || c == c2;
31}
32
33bool 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