Linux: move SyncIPC function from Skia to base.

I'll be needing in some pending WebKit changes.

http://codereview.chromium.org/131006


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18676 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 18 insertions, 0 deletions

diff --git a/base/unix_domain_socket_posix.h b/base/unix_domain_socket_posix.h
index c0b40e8..4274a64 100644
--- a/base/unix_domain_socket_posix.h
+++ b/base/unix_domain_socket_posix.h
@@ -8,6 +8,8 @@
 #include <sys/types.h>
 #include <vector>
 
+class Pickle;
+
 namespace base {
 
 // Use sendmsg to write the given msg and include a vector
@@ -17,6 +19,22 @@ bool SendMsg(int fd, const void* msg, size_t length,
 // Use recvmsg to read a message and an array of file descriptors. Returns
 // -1 on failure. Note: will read, at most, 16 descriptors.
 ssize_t RecvMsg(int fd, void* msg, size_t length, std::vector<int>* fds);
+// Perform a sendmsg/recvmsg pair.
+//   1. This process creates a UNIX DGRAM socketpair.
+//   2. This proces writes a request to |fd| with an SCM_RIGHTS control message
+//      containing on end of the fresh socket pair.
+//   3. This process blocks reading from the other end of the fresh socketpair.
+//   4. The target process receives the request, processes it and writes the
+//      reply to the end of the socketpair contained in the request.
+//   5. This process wakes up and continues.
+//
+//   fd: descriptor to send the request on
+//   reply: buffer for the reply
+//   reply_len: size of |reply|
+//   result_fd: (may be NULL) the file descriptor returned in the reply (if any)
+//   request: the bytes to send in the request
+ssize_t SendRecvMsg(int fd, uint8_t* reply, unsigned reply_len, int* result_fd,
+                    const Pickle& request);
 
 }  // namespace base