1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MOJO_EMBEDDER_PLATFORM_CHANNEL_UTILS_POSIX_H_ 6 #define MOJO_EMBEDDER_PLATFORM_CHANNEL_UTILS_POSIX_H_ 7 8 #include <stddef.h> 9 #include <sys/types.h> // For |ssize_t|. 10 11 #include <deque> 12 13 #include "base/memory/scoped_ptr.h" 14 #include "mojo/embedder/platform_handle.h" 15 #include "mojo/system/system_impl_export.h" 16 17 struct iovec; // Declared in <sys/uio.h>. 18 19 namespace mojo { 20 namespace embedder { 21 22 // The maximum number of handles that can be sent "at once" using 23 // |PlatformChannelSendmsgWithHandles()|. 24 // TODO(vtl): This number is taken from ipc/file_descriptor_set_posix.h: 25 // |FileDescriptorSet::kMaxDescriptorsPerMessage|. Where does it come from? 26 const size_t kPlatformChannelMaxNumHandles = 7; 27 28 // Use these to write to a socket created using |PlatformChannelPair| (or 29 // equivalent). These are like |write()| and |writev()|, but handle |EINTR| and 30 // never raise |SIGPIPE|. (Note: On Mac, the suppression of |SIGPIPE| is set up 31 // by |PlatformChannelPair|.) 32 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelWrite(PlatformHandle h, 33 const void* bytes, 34 size_t num_bytes); 35 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelWritev(PlatformHandle h, 36 struct iovec* iov, 37 size_t num_iov); 38 39 // Writes data, and the given set of |PlatformHandle|s (i.e., file descriptors) 40 // over the Unix domain socket given by |h| (e.g., created using 41 // |PlatformChannelPair()|). All the handles must be valid, and there must be at 42 // least one and at most |kPlatformChannelMaxNumHandles| handles. The return 43 // value is as for |sendmsg()|, namely -1 on failure and otherwise the number of 44 // bytes of data sent on success (note that this may not be all the data 45 // specified by |iov|). (The handles are not closed, regardless of success or 46 // failure.) 47 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelSendmsgWithHandles( 48 PlatformHandle h, 49 struct iovec* iov, 50 size_t num_iov, 51 PlatformHandle* platform_handles, 52 size_t num_platform_handles); 53 54 // TODO(vtl): Remove this once I've switched things over to 55 // |PlatformChannelSendmsgWithHandles()|. 56 // Sends |PlatformHandle|s (i.e., file descriptors) over the Unix domain socket 57 // (e.g., created using PlatformChannelPair|). (These will be sent in a single 58 // message having one null byte of data and one control message header with all 59 // the file descriptors.) All of the handles must be valid, and there must be at 60 // most |kPlatformChannelMaxNumHandles| (and at least one handle). Returns true 61 // on success, in which case it closes all the handles. 62 MOJO_SYSTEM_IMPL_EXPORT bool PlatformChannelSendHandles(PlatformHandle h, 63 PlatformHandle* handles, 64 size_t num_handles); 65 66 // Wrapper around |recvmsg()|, which will extract any attached file descriptors 67 // (in the control message) to |PlatformHandle|s (and append them to 68 // |platform_handles|). (This also handles |EINTR|.) 69 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelRecvmsg( 70 PlatformHandle h, 71 void* buf, 72 size_t num_bytes, 73 std::deque<PlatformHandle>* platform_handles); 74 75 } // namespace embedder 76 } // namespace mojo 77 78 #endif // MOJO_EMBEDDER_PLATFORM_CHANNEL_UTILS_POSIX_H_ 79
