Added socket send and recv timeout options (#1419)

Added socket send and recv timeout options with implementation for posix platform.

This is part of a extending support for sockets in WASI. #1336.

Also add sample that sets and reads back the send and receive timeouts using
the native function binding.

samples/socket-api/CMakeLists.txt

@@ -90,6 +90,7 @@ ExternalProject_Add(wasm-app
                       tcp_client.wasm ${CMAKE_CURRENT_SOURCE_DIR}/build
                       tcp_server.wasm ${CMAKE_CURRENT_SOURCE_DIR}/build
                       send_recv.wasm ${CMAKE_CURRENT_SOURCE_DIR}/build
+                      socket_opts.wasm ${CMAKE_CURRENT_SOURCE_DIR}/build
 )
 
 add_executable(tcp_server ${CMAKE_CURRENT_SOURCE_DIR}/wasm-src/tcp_server.c)
@@ -102,6 +103,8 @@ target_link_libraries(send_recv pthread)
 
 add_executable(addr_resolve ${CMAKE_CURRENT_SOURCE_DIR}/wasm-src/addr_resolve.c)
 
+add_executable(socket_opts ${CMAKE_CURRENT_SOURCE_DIR}/wasm-src/socket_opts.c)
+
 ############################################
 ## Build iwasm with wasi and pthread support
 ############################################

samples/socket-api/README.md

@@ -82,4 +82,17 @@ Data:
   And mourns for us
 ```
 
+`socket_opts.wasm` shows an example of getting and setting various supported socket options
+```bash
+$ ./iwasm ./socket_opts.wasm
+```
+
+The output is:
+```bash
+[Client] Create socket
+recv_timeout is expected
+send_timeout is expected
+[Client] Close socket
+```
+
 Refer to [socket api document](../../doc/socket_api.md) for more details.

samples/socket-api/wasm-src/CMakeLists.txt

@@ -80,3 +80,4 @@ compile_with_clang(tcp_server.c)
 compile_with_clang(tcp_client.c)
 compile_with_clang(send_recv.c)
 compile_with_clang(addr_resolve.c)
+compile_with_clang(socket_opts.c)

samples/socket-api/wasm-src/socket_opts.c

@@ -0,0 +1,56 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#ifdef __wasi__
+#include <wasi_socket_ext.h>
+#endif
+
+#define OPTION_ASSERT(A, B, OPTION)           \
+    if (A == B) {                             \
+        printf("%s is expected\n", OPTION);   \
+    }                                         \
+    else {                                    \
+        printf("%s is unexpected\n", OPTION); \
+        return EXIT_FAILURE;                  \
+    }
+
+struct timeval
+to_timeval(time_t tv_sec, suseconds_t tv_usec)
+{
+    struct timeval tv = { tv_sec, tv_usec };
+    return tv;
+}
+
+int
+main(int argc, char *argv[])
+{
+    int socket_fd = 0;
+    struct timeval tv;
+    socklen_t tv_len = sizeof(tv);
+
+    printf("[Client] Create socket\n");
+    socket_fd = socket(AF_INET, SOCK_STREAM, 0);
+    if (socket_fd == -1) {
+        perror("Create socket failed");
+        return EXIT_FAILURE;
+    }
+
+    tv = to_timeval(123, 1000);
+    setsockopt(socket_fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
+    tv = to_timeval(0, 0);
+    getsockopt(socket_fd, SOL_SOCKET, SO_RCVTIMEO, &tv, &tv_len);
+    OPTION_ASSERT(tv.tv_sec, 123, "SO_RCVTIMEO tv_sec");
+    OPTION_ASSERT(tv.tv_usec, 1000, "SO_RCVTIMEO tv_usec");
+
+    tv = to_timeval(456, 2000);
+    setsockopt(socket_fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
+    tv = to_timeval(0, 0);
+    getsockopt(socket_fd, SOL_SOCKET, SO_SNDTIMEO, &tv, &tv_len);
+    OPTION_ASSERT(tv.tv_sec, 456, "SO_SNDTIMEO tv_sec");
+    OPTION_ASSERT(tv.tv_usec, 2000, "SO_SNDTIMEO tv_usec");
+
+    printf("[Client] Close socket\n");
+    close(socket_fd);
+    return EXIT_SUCCESS;
+}