diff options
Diffstat (limited to 'base/shared_memory.h')
| -rw-r--r-- | base/shared_memory.h | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/base/shared_memory.h b/base/shared_memory.h index b44367a..744b348 100644 --- a/base/shared_memory.h +++ b/base/shared_memory.h @@ -8,6 +8,7 @@ #include "build/build_config.h" #if defined(OS_POSIX) +#include <sys/types.h> #include <semaphore.h> #include "base/file_descriptor_posix.h" #endif @@ -24,7 +25,10 @@ namespace base { typedef HANDLE SharedMemoryHandle; typedef HANDLE SharedMemoryLock; #elif defined(OS_POSIX) +// A SharedMemoryId is sufficient to identify a given shared memory segment on a +// system, but insufficient to map it. typedef FileDescriptor SharedMemoryHandle; +typedef ino_t SharedMemoryId; // On POSIX, the lock is implemented as a lockf() on the mapped file, // so no additional member (or definition of SharedMemoryLock) is // needed. @@ -99,6 +103,14 @@ class SharedMemory { // identifier is not portable. SharedMemoryHandle handle() const; +#if defined(OS_POSIX) + // Return a unique identifier for this shared memory segment. Inode numbers + // are technically only unique to a single filesystem. However, we always + // allocate shared memory backing files from the same directory, so will end + // up on the same filesystem. + SharedMemoryId id() const { return inode_; } +#endif + // Closes the open shared memory segment. // It is safe to call Close repeatedly. void Close(); @@ -153,9 +165,10 @@ class SharedMemory { std::wstring name_; #if defined(OS_WIN) - HANDLE mapped_file_; + HANDLE mapped_file_; #elif defined(OS_POSIX) - int mapped_file_; + int mapped_file_; + ino_t inode_; #endif void* memory_; bool read_only_; |