libsanitizer/sanitizer_common/sanitizer_procmaps_linux.cc

   1 //===-- sanitizer_procmaps_linux.cc ---------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // Information about the process mappings (Linux-specific parts).
   9 //===----------------------------------------------------------------------===//
  10
  11 #include "sanitizer_platform.h"
  12 #if SANITIZER_LINUX
  13 #include "sanitizer_common.h"
  14 #include "sanitizer_procmaps.h"
  15
  16 namespace __sanitizer {
  17
  18 void ReadProcMaps(ProcSelfMapsBuff *proc_maps) {
  19   if (!ReadFileToBuffer("/proc/self/maps", &proc_maps->data,
  20                         &proc_maps->mmaped_size, &proc_maps->len)) {
  21     proc_maps->data = nullptr;
  22     proc_maps->mmaped_size = 0;
  23     proc_maps->len = 0;
  24   }
  25 }
  26
  27 static bool IsOneOf(char c, char c1, char c2) {
  28   return c == c1 || c == c2;
  29 }
  30
  31 bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
  32   char *last = data_.proc_self_maps.data + data_.proc_self_maps.len;
  33   if (data_.current >= last) return false;
  34   char *next_line =
  35       (char *)internal_memchr(data_.current, '\n', last - data_.current);
  36   if (next_line == 0)
  37     next_line = last;
  38   // Example: 08048000-08056000 r-xp 00000000 03:0c 64593   /foo/bar
  39   segment->start = ParseHex(&data_.current);
  40   CHECK_EQ(*data_.current++, '-');
  41   segment->end = ParseHex(&data_.current);
  42   CHECK_EQ(*data_.current++, ' ');
  43   CHECK(IsOneOf(*data_.current, '-', 'r'));
  44   segment->protection = 0;
  45   if (*data_.current++ == 'r') segment->protection |= kProtectionRead;
  46   CHECK(IsOneOf(*data_.current, '-', 'w'));
  47   if (*data_.current++ == 'w') segment->protection |= kProtectionWrite;
  48   CHECK(IsOneOf(*data_.current, '-', 'x'));
  49   if (*data_.current++ == 'x') segment->protection |= kProtectionExecute;
  50   CHECK(IsOneOf(*data_.current, 's', 'p'));
  51   if (*data_.current++ == 's') segment->protection |= kProtectionShared;
  52   CHECK_EQ(*data_.current++, ' ');
  53   segment->offset = ParseHex(&data_.current);
  54   CHECK_EQ(*data_.current++, ' ');
  55   ParseHex(&data_.current);
  56   CHECK_EQ(*data_.current++, ':');
  57   ParseHex(&data_.current);
  58   CHECK_EQ(*data_.current++, ' ');
  59   while (IsDecimal(*data_.current)) data_.current++;
  60   // Qemu may lack the trailing space.
  61   // https://github.com/google/sanitizers/issues/160
  62   // CHECK_EQ(*data_.current++, ' ');
  63   // Skip spaces.
  64   while (data_.current < next_line && *data_.current == ' ') data_.current++;
  65   // Fill in the filename.
  66   if (segment->filename) {
  67     uptr len =
  68         Min((uptr)(next_line - data_.current), segment->filename_size - 1);
  69     internal_strncpy(segment->filename, data_.current, len);
  70     segment->filename[len] = 0;
  71   }
  72
  73   data_.current = next_line + 1;
  74   return true;
  75 }
  76
  77 }  // namespace __sanitizer
  78
  79 #endif  // SANITIZER_LINUX