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   CHECK(ReadFileToBuffer("/proc/self/maps", &proc_maps->data,
  20                          &proc_maps->mmaped_size, &proc_maps->len));
  21 }
  22
  23 static bool IsOneOf(char c, char c1, char c2) {
  24   return c == c1 || c == c2;
  25 }
  26
  27 bool MemoryMappingLayout::Next(uptr *start, uptr *end, uptr *offset,
  28                                char filename[], uptr filename_size,
  29                                uptr *protection) {
  30   char *last = proc_self_maps_.data + proc_self_maps_.len;
  31   if (current_ >= last) return false;
  32   uptr dummy;
  33   if (!start) start = &dummy;
  34   if (!end) end = &dummy;
  35   if (!offset) offset = &dummy;
  36   if (!protection) protection = &dummy;
  37   char *next_line = (char*)internal_memchr(current_, '\n', last - current_);
  38   if (next_line == 0)
  39     next_line = last;
  40   // Example: 08048000-08056000 r-xp 00000000 03:0c 64593   /foo/bar
  41   *start = ParseHex(&current_);
  42   CHECK_EQ(*current_++, '-');
  43   *end = ParseHex(&current_);
  44   CHECK_EQ(*current_++, ' ');
  45   CHECK(IsOneOf(*current_, '-', 'r'));
  46   *protection = 0;
  47   if (*current_++ == 'r')
  48     *protection |= kProtectionRead;
  49   CHECK(IsOneOf(*current_, '-', 'w'));
  50   if (*current_++ == 'w')
  51     *protection |= kProtectionWrite;
  52   CHECK(IsOneOf(*current_, '-', 'x'));
  53   if (*current_++ == 'x')
  54     *protection |= kProtectionExecute;
  55   CHECK(IsOneOf(*current_, 's', 'p'));
  56   if (*current_++ == 's')
  57     *protection |= kProtectionShared;
  58   CHECK_EQ(*current_++, ' ');
  59   *offset = ParseHex(&current_);
  60   CHECK_EQ(*current_++, ' ');
  61   ParseHex(&current_);
  62   CHECK_EQ(*current_++, ':');
  63   ParseHex(&current_);
  64   CHECK_EQ(*current_++, ' ');
  65   while (IsDecimal(*current_))
  66     current_++;
  67   // Qemu may lack the trailing space.
  68   // https://github.com/google/sanitizers/issues/160
  69   // CHECK_EQ(*current_++, ' ');
  70   // Skip spaces.
  71   while (current_ < next_line && *current_ == ' ')
  72     current_++;
  73   // Fill in the filename.
  74   uptr i = 0;
  75   while (current_ < next_line) {
  76     if (filename && i < filename_size - 1)
  77       filename[i++] = *current_;
  78     current_++;
  79   }
  80   if (filename && i < filename_size)
  81     filename[i] = 0;
  82   current_ = next_line + 1;
  83   return true;
  84 }
  85
  86 }  // namespace __sanitizer
  87
  88 #endif  // SANITIZER_LINUX