libsanitizer/sanitizer_common/sanitizer_procmaps.h

   1 //===-- sanitizer_procmaps.h ------------------------------------*- C++ -*-===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is shared between AddressSanitizer and ThreadSanitizer.
   9 //
  10 // Information about the process mappings.
  11 //===----------------------------------------------------------------------===//
  12 #ifndef SANITIZER_PROCMAPS_H
  13 #define SANITIZER_PROCMAPS_H
  14
  15 #include "sanitizer_internal_defs.h"
  16
  17 namespace __sanitizer {
  18
  19 #ifdef _WIN32
  20 class MemoryMappingLayout {
  21  public:
  22   MemoryMappingLayout() {}
  23   bool GetObjectNameAndOffset(uptr addr, uptr *offset,
  24                               char filename[], uptr filename_size) {
  25     UNIMPLEMENTED();
  26   }
  27 };
  28
  29 #else  // _WIN32
  30 class MemoryMappingLayout {
  31  public:
  32   MemoryMappingLayout();
  33   bool Next(uptr *start, uptr *end, uptr *offset,
  34             char filename[], uptr filename_size);
  35   void Reset();
  36   // Gets the object file name and the offset in that object for a given
  37   // address 'addr'. Returns true on success.
  38   bool GetObjectNameAndOffset(uptr addr, uptr *offset,
  39                               char filename[], uptr filename_size);
  40   ~MemoryMappingLayout();
  41
  42  private:
  43   // Default implementation of GetObjectNameAndOffset.
  44   // Quite slow, because it iterates through the whole process map for each
  45   // lookup.
  46   bool IterateForObjectNameAndOffset(uptr addr, uptr *offset,
  47                                      char filename[], uptr filename_size) {
  48     Reset();
  49     uptr start, end, file_offset;
  50     for (int i = 0; Next(&start, &end, &file_offset, filename, filename_size);
  51          i++) {
  52       if (addr >= start && addr < end) {
  53         // Don't subtract 'start' for the first entry:
  54         // * If a binary is compiled w/o -pie, then the first entry in
  55         //   process maps is likely the binary itself (all dynamic libs
  56         //   are mapped higher in address space). For such a binary,
  57         //   instruction offset in binary coincides with the actual
  58         //   instruction address in virtual memory (as code section
  59         //   is mapped to a fixed memory range).
  60         // * If a binary is compiled with -pie, all the modules are
  61         //   mapped high at address space (in particular, higher than
  62         //   shadow memory of the tool), so the module can't be the
  63         //   first entry.
  64         *offset = (addr - (i ? start : 0)) + file_offset;
  65         return true;
  66       }
  67     }
  68     if (filename_size)
  69       filename[0] = '\0';
  70     return false;
  71   }
  72
  73 # if defined __linux__
  74   char *proc_self_maps_buff_;
  75   uptr proc_self_maps_buff_mmaped_size_;
  76   uptr proc_self_maps_buff_len_;
  77   char *current_;
  78 # elif defined __APPLE__
  79   template<u32 kLCSegment, typename SegmentCommand>
  80   bool NextSegmentLoad(uptr *start, uptr *end, uptr *offset,
  81                        char filename[], uptr filename_size);
  82   int current_image_;
  83   u32 current_magic_;
  84   u32 current_filetype_;
  85   int current_load_cmd_count_;
  86   char *current_load_cmd_addr_;
  87 # endif
  88 };
  89
  90 #endif  // _WIN32
  91
  92 }  // namespace __sanitizer
  93
  94 #endif  // SANITIZER_PROCMAPS_H