Upstream android file related code.

base/shared_memory_posix.cc

Index: base/shared_memory_posix.cc
diff --git a/base/shared_memory_posix.cc b/base/shared_memory_posix.cc
index 7a238ed880b12a641b7461fc01285b7d169d9cc2..5651dc0232bac4dd5865d5ff7448df82ba4bbe02 100644
--- a/base/shared_memory_posix.cc
+++ b/base/shared_memory_posix.cc
@@ -24,10 +24,21 @@
 namespace base {
 
 namespace {
+
 // Paranoia. Semaphores and shared memory segments should live in different
 // namespaces, but who knows what's out there.
 const char kSemaphoreSuffix[] = "-sem";
+
+#if defined(OS_ANDROID)
+// The lockf() function is not available on Android; we translate to flock().
+#define F_LOCK LOCK_EX
+#define F_ULOCK LOCK_UN
+inline int lockf(int fd, int cmd, off_t ignored_len) {
+  return flock(fd, cmd);
 }
+#endif
+
+}  // namespace.
 
 SharedMemory::SharedMemory()
     : mapped_file_(-1),
@@ -95,6 +106,7 @@ bool SharedMemory::CreateAnonymous(uint32 size) {
   return CreateNamed("", false, size);
 }
 
+#if !defined(OS_ANDROID)
 // Chromium mostly only uses the unique/private shmem as specified by
 // "name == L"". The exception is in the StatsTable.
 // TODO(jrg): there is no way to "clean up" all unused named shmem if
@@ -177,6 +189,7 @@ bool SharedMemory::CreateNamed(const std::string& name,
 // These files need to be deleted explicitly.
 // In practice this call is only needed for unit tests.
 bool SharedMemory::Delete(const std::string& name) {
+

[joth, 2011/06/19 12:48:05]

nit: remove \n

[michaelbai, 2011/06/20 22:50:36]

Done.

   FilePath path;
   if (!FilePathForMemoryName(name, &path))
     return false;
@@ -201,10 +214,25 @@ bool SharedMemory::Open(const std::string& name, bool read_only) {
   return PrepareMapFile(fp);
 }
 
+#endif  // !defined(OS_ANDROID)
+
 bool SharedMemory::Map(uint32 bytes) {
   if (mapped_file_ == -1)
     return false;
 
+#if defined(OS_ANDROID)
+  int ashmem_bytes = GetAshmenSizeRegion();
+  DCHECK_GE((uint32)ashmem_bytes, bytes);

[joth, 2011/06/19 12:48:05]

nit: static_cast<uint32>(ashmem_bytes) although this check will be ineffective
if GetAshmenSizeRegion returns -1
-> should check for negative return value and return false(?)
-> could the GetAshmenSizeRegion() call not go inside the if (bytes == 0) below?

[michaelbai, 2011/06/20 22:50:36]

Done.

+  if (bytes == 0) {
+    // The caller wants to determine the map region size from ashmem.
+    bytes = ashmem_bytes;
+    // TODO(port): we set the created size here so that it is available in
+    // transport_dib_android.cc. We should use
+    // SharedMemory::GetAshmenSizeRegion() in TransportDIB::Map().
+    created_size_ = bytes;
+  }
+#endif

[joth, 2011/06/19 12:48:05]

seems unfortunate to commit this hack when the code depending on it is can be
fixed before being committed itself, but there we go.

+
   memory_ = mmap(NULL, bytes, PROT_READ | (read_only_ ? 0 : PROT_WRITE),
                  MAP_SHARED, mapped_file_, 0);
 
@@ -248,6 +276,7 @@ void SharedMemory::Unlock() {
   LockOrUnlockCommon(F_ULOCK);
 }
 
+#if !defined(OS_ANDROID)
 bool SharedMemory::PrepareMapFile(FILE *fp) {
   DCHECK_EQ(-1, mapped_file_);
   if (fp == NULL) return false;
@@ -276,6 +305,7 @@ bool SharedMemory::PrepareMapFile(FILE *fp) {
 
   return true;
 }
+#endif
 
 // For the given shmem named |mem_name|, return a filename to mmap()
 // (and possibly create).  Modifies |filename|.  Return false on