[libc] Add functions to send/recv messages (#106467)

This patch adds the necessary functions to send and receive messages
over a socket. Those functions are: recv, recvfrom, recvmsg, send,
sendto, sendmsg, and socketpair for testing.

Author: michaelrj-google

libc/config/linux/api.td

@@ -193,6 +193,10 @@ def SysSocketAPI : PublicAPI<"sys/socket.h"> {
     "socklen_t",
     "struct sockaddr",
     "struct sockaddr_un",
+    "struct msghdr",
+    "struct iovec",
+    "size_t",
+    "ssize_t",
   ];
 }
 

libc/config/linux/x86_64/entrypoints.txt

@@ -1041,8 +1041,14 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.sys.select.select
 
     # sys/socket.h entrypoints
-    libc.src.sys.socket.bind
     libc.src.sys.socket.socket
+    libc.src.sys.socket.socketpair
+    libc.src.sys.socket.send
+    libc.src.sys.socket.sendto
+    libc.src.sys.socket.sendmsg
+    libc.src.sys.socket.recv
+    libc.src.sys.socket.recvfrom
+    libc.src.sys.socket.recvmsg
   )
 endif()
 

libc/hdr/types/CMakeLists.txt

@@ -199,3 +199,30 @@ add_proxy_header_library(
     libc.include.setjmp
 )
 
+
+add_proxy_header_library(
+  struct_msghdr
+  HDRS
+    struct_msghdr.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.struct_msghdr
+    libc.include.sys_socket
+)
+
+add_proxy_header_library(
+  struct_sockaddr
+  HDRS
+    struct_sockaddr.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.struct_sockaddr
+    libc.include.sys_socket
+)
+
+add_proxy_header_library(
+  socklen_t
+  HDRS
+    socklen_t.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.socklen_t
+    libc.include.sys_socket
+)

libc/hdr/types/socklen_t.h

@@ -0,0 +1,21 @@
+//===-- Proxy for socklen_t -----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_LIBC_HDR_TYPES_SOCKLEN_T_H
+#define LLVM_LIBC_HDR_TYPES_SOCKLEN_T_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/socklen_t.h"
+
+#else
+
+#include <signal.h>
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_SOCKLEN_T_H

libc/hdr/types/ssize_t.h

@@ -0,0 +1,23 @@
+//===-- Proxy for ssize_t -------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_LIBC_HDR_TYPES_SSIZE_T_H
+#define LLVM_LIBC_HDR_TYPES_SSIZE_T_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/ssize_t.h"
+
+#else
+
+#define __need_ssize_t
+#include <stddef.h>
+#undef __need_ssize_t
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_SSIZE_T_H

libc/hdr/types/struct_msghdr.h

@@ -0,0 +1,21 @@
+//===-- Proxy for struct msghdr  ------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_LIBC_HDR_TYPES_STRUCT_MSGHDR_H
+#define LLVM_LIBC_HDR_TYPES_STRUCT_MSGHDR_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/struct_msghdr.h"
+
+#else
+
+#include <sys/socket.h>
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_STRUCT_MSGHDR_H

libc/hdr/types/struct_sockaddr.h

@@ -0,0 +1,21 @@
+//===-- Proxy for struct sockaddr  ----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_LIBC_HDR_TYPES_STRUCT_SOCKADDR_H
+#define LLVM_LIBC_HDR_TYPES_STRUCT_SOCKADDR_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/struct_sockaddr.h"
+
+#else
+
+#include <sys/socket.h>
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_STRUCT_SOCKADDR_H

libc/include/CMakeLists.txt

@@ -593,6 +593,8 @@ add_header_macro(
     .llvm-libc-macros.sys_socket_macros
     .llvm-libc-types.sa_family_t
     .llvm-libc-types.socklen_t
+    .llvm-libc-types.struct_iovec
+    .llvm-libc-types.struct_msghdr
     .llvm-libc-types.struct_sockaddr
     .llvm-libc-types.struct_sockaddr_un
 )

libc/include/llvm-libc-types/CMakeLists.txt

@@ -117,8 +117,10 @@ add_header(
 add_header(wint_t HDR wint_t.h)
 add_header(sa_family_t HDR sa_family_t.h)
 add_header(socklen_t HDR socklen_t.h)
-add_header(struct_sockaddr_un HDR struct_sockaddr_un.h)
-add_header(struct_sockaddr HDR struct_sockaddr.h)
+add_header(struct_sockaddr_un HDR struct_sockaddr_un.h DEPENDS .sa_family_t)
+add_header(struct_sockaddr HDR struct_sockaddr.h DEPENDS .sa_family_t)
+add_header(struct_iovec HDR struct_iovec.h DEPENDS .size_t)
+add_header(struct_msghdr HDR struct_msghdr.h DEPENDS .size_t .socklen_t .struct_iovec)
 add_header(rpc_opcodes_t HDR rpc_opcodes_t.h)
 add_header(ACTION HDR ACTION.h)
 add_header(ENTRY HDR ENTRY.h)

libc/include/llvm-libc-types/struct_iovec.h

@@ -0,0 +1,19 @@
+//===-- Definition of struct iovec ----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_TYPES_STRUCT_IOVEC_H
+#define LLVM_LIBC_TYPES_STRUCT_IOVEC_H
+
+#include "size_t.h"
+
+struct iovec {
+  void *iov_base;
+  size_t iov_len;
+};
+
+#endif // LLVM_LIBC_TYPES_STRUCT_IOVEC_H