src/ipc/mem/Page.h

   1 /*
   2  */
   3
   4 #ifndef SQUID_IPC_MEM_PAGE_H
   5 #define SQUID_IPC_MEM_PAGE_H
   6
   7 #if HAVE_IOSFWD
   8 #include <iosfwd>
   9 #endif
  10
  11 namespace Ipc
  12 {
  13
  14 namespace Mem
  15 {
  16
  17 /// Shared memory page identifier, address, or handler
  18 class PageId
  19 {
  20 public:
  21     PageId(): pool(0), number(0), purpose(maxPurpose) {}
  22
  23     /// true if and only if both critical components have been initialized
  24     bool set() const { return pool && number; }
  25
  26     // safer than bool which would enable silent casts to int
  27     typedef const uint32_t PageId::*SaferBool;
  28     operator SaferBool() const { return set() ? &PageId::number : NULL; }
  29
  30     uint32_t pool; ///< page pool ID within Squid
  31     // uint32_t segment; ///< memory segment ID within the pool; unused for now
  32     uint32_t number; ///< page number within the segment
  33
  34     enum Purpose { cachePage, ioPage, maxPurpose };
  35     Purpose purpose; ///< page purpose
  36 };
  37
  38 /// writes page address (e.g., "sh_page5.3"), for debugging
  39 std::ostream &operator <<(std::ostream &os, const PageId &page);
  40
  41 } // namespace Mem
  42
  43 } // namespace Ipc
  44
  45 #endif // SQUID_IPC_MEM_PAGE_H