Add a vsock server/client example of interaction with C lib #27

build.rs is added to rust-vsock-payload to set location and name of
the C static library. Method to set these information is added to
vsock readme.md.

In vsock_c_lib/main.c, socket interfaces provided by rust is called
to implement a server and a client.

In main.rs of rust-vsock-payload, these two functions implemented by
C lib is called for a test.

Signed-off-by: Jiaqi Gao <[email protected]>

rust-vsock-payload/build.rs

@@ -0,0 +1,8 @@
+use std::env;
+
+fn main() {
+    let out_dir = env::var("RUST_LINK_C_LIB_DIR").unwrap();
+    let lib_name = env::var("RUST_LINK_C_LIB_NAME").unwrap();
+    println!("cargo:rustc-link-search=native={}", out_dir);
+    println!("cargo:rustc-link-lib=static={}", lib_name);
+}

rust-vsock-payload/readme.md

@@ -12,6 +12,12 @@ export RUST_IPL_BIN=$BASE_DIR/target/x86_64-unknown-uefi/release/rust_ipl.efi
 export RUST_PAYLOAD_BIN=$BASE_DIR/target/x86_64-unknown-uefi/release/rust-vsock-payload.efi
 export RUST_FIRMWARE_BIN=$BASE_DIR/target/x86_64-unknown-uefi/release/final_vsock.bin
 ```
+To link a static C library, set the folder and name of lib to the environment variable:
+
+```bash
+export RUST_LINK_C_LIB_DIR=$BASE_DIR/rust-vsock-payload/
+export RUST_LINK_C_LIB_NAME=main.a
+```
 
 To build default PE format OBJ and link with a static C library:
 

rust-vsock-payload/src/main.rs

@@ -18,6 +18,13 @@ mod vsock_impl;
 
 mod client;
 mod server;
+mod vsock_lib;
+
+#[link(name = "main")]
+extern "C" {
+    fn server_entry() -> i32;
+    fn client_entry() -> i32;
+}
 
 #[no_mangle]
 #[cfg_attr(target_os = "uefi", export_name = "efi_main")]
@@ -45,17 +52,24 @@ pub extern "win64" fn _start(hob_list: *const u8, _reserved_param: usize) -> ! {
 
     vsock_impl::init_vsock_device();
 
-    client::test_client();
-    server::test_server();
+    // client::test_client();
+    let mut result;
+    unsafe {
+        result = client_entry();
+    }
+    log::debug!("Client example done: {}\n", result);
+
+    // server::test_server();
+    unsafe {
+        result = server_entry();
+    }
 
-    log::debug!("Example done\n");
+    log::debug!("Server Example done: {}\n", result);
     loop {}
 }
 
-#[cfg(target_os = "uefi")]
 use core::panic::PanicInfo;
 
-#[cfg(target_os = "uefi")]
 #[panic_handler]
 fn panic(_info: &PanicInfo) -> ! {
     rust_ipl_log::write_log(

rust-vsock-payload/vsock_c_lib/main.c

@@ -0,0 +1,96 @@
+//
+// Copyright (c) 2021 Intel Corporation
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// This example does the same work as rust-vsock-payload/src/server.rs
+//
+
+#include <sys/types.h>
+
+typedef unsigned int socklen_t;
+
+struct sockaddr {
+	unsigned short svm_family;
+	unsigned short svm_reserved1;
+	unsigned int   svm_port;
+	unsigned int   svm_cid;
+	unsigned char  svm_flags;
+	unsigned char  svm_zero[3];
+};
+
+extern int     socket (int family, int type, int protocol);
+extern int     bind (int sockfd, const struct sockaddr *addr,socklen_t addrlen);
+extern int     listen (int sockfd, int backlog);
+extern int     accept (int sockfd, struct sockaddr *addr, socklen_t *addrlen);
+extern ssize_t recv (int sockfd, void *buf, size_t len, int flags);
+extern int     connect (int sockfd, const struct sockaddr *addr,socklen_t addrlen);
+extern ssize_t send (int sockfd, void *buf, size_t len, int flags);
+extern int     shutdown (int fd, int how);
+
+#define RECV_BUF_LEN 1024
+
+int server_entry () {
+  int             sockfd;
+  unsigned char   buf[1024];
+  struct sockaddr bindAddr;
+  socklen_t       bindAddrLen;
+  struct sockaddr acceptAddr;
+  socklen_t       acceptAddrLen;
+
+  bindAddr.svm_port = 1234;
+  bindAddr.svm_cid  = 33;
+  bindAddrLen       = 11;
+
+  sockfd = socket (0, 0, 0);
+
+  if (bind (sockfd, &bindAddr, bindAddrLen)) {
+    return -1;
+  }
+
+  if (listen (sockfd, 1)) {
+    return -1;
+  }
+
+  if (accept (sockfd, &acceptAddr, &acceptAddrLen)) {
+    return -1;
+  }
+
+  while (1) {
+    if (!recv (sockfd, buf, 1024, 0)) {
+      break;
+    }
+  }
+
+  if (shutdown (sockfd, 0)) {
+    return -1;
+  }
+  return 0;
+}
+
+
+
+int client_entry () {
+  int             sockfd;
+  struct sockaddr serverAddr;
+  socklen_t       serverAddrLen;
+
+  sockfd = socket (0, 0, 0);
+
+  serverAddr.svm_port = 1234;
+  serverAddr.svm_cid  = 2;
+  serverAddrLen       = 11;
+
+  if (connect (sockfd, &serverAddr, serverAddrLen)) {
+      return -1;
+  }
+
+  if (send (sockfd, "hello", 5, 0)) {
+    return -1;
+  }
+
+  if (shutdown (sockfd, 0)) {
+    return -1;
+  }
+  return 0;
+}