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-rw-r--r--tools/testing/vsock/control.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/tools/testing/vsock/control.c b/tools/testing/vsock/control.c
new file mode 100644
index 000000000000..90fd47f0e422
--- /dev/null
+++ b/tools/testing/vsock/control.c
@@ -0,0 +1,219 @@
+/* Control socket for client/server test execution
+ *
+ * Copyright (C) 2017 Red Hat, Inc.
+ *
+ * Author: Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+/* The client and server may need to coordinate to avoid race conditions like
+ * the client attempting to connect to a socket that the server is not
+ * listening on yet. The control socket offers a communications channel for
+ * such coordination tasks.
+ *
+ * If the client calls control_expectln("LISTENING"), then it will block until
+ * the server calls control_writeln("LISTENING"). This provides a simple
+ * mechanism for coordinating between the client and the server.
+ */
+
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include "timeout.h"
+#include "control.h"
+
+static int control_fd = -1;
+
+/* Open the control socket, either in server or client mode */
+void control_init(const char *control_host,
+ const char *control_port,
+ bool server)
+{
+ struct addrinfo hints = {
+ .ai_socktype = SOCK_STREAM,
+ };
+ struct addrinfo *result = NULL;
+ struct addrinfo *ai;
+ int ret;
+
+ ret = getaddrinfo(control_host, control_port, &hints, &result);
+ if (ret != 0) {
+ fprintf(stderr, "%s\n", gai_strerror(ret));
+ exit(EXIT_FAILURE);
+ }
+
+ for (ai = result; ai; ai = ai->ai_next) {
+ int fd;
+ int val = 1;
+
+ fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+ if (fd < 0)
+ continue;
+
+ if (!server) {
+ if (connect(fd, ai->ai_addr, ai->ai_addrlen) < 0)
+ goto next;
+ control_fd = fd;
+ printf("Control socket connected to %s:%s.\n",
+ control_host, control_port);
+ break;
+ }
+
+ if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+ &val, sizeof(val)) < 0) {
+ perror("setsockopt");
+ exit(EXIT_FAILURE);
+ }
+
+ if (bind(fd, ai->ai_addr, ai->ai_addrlen) < 0)
+ goto next;
+ if (listen(fd, 1) < 0)
+ goto next;
+
+ printf("Control socket listening on %s:%s\n",
+ control_host, control_port);
+ fflush(stdout);
+
+ control_fd = accept(fd, NULL, 0);
+ close(fd);
+
+ if (control_fd < 0) {
+ perror("accept");
+ exit(EXIT_FAILURE);
+ }
+ printf("Control socket connection accepted...\n");
+ break;
+
+next:
+ close(fd);
+ }
+
+ if (control_fd < 0) {
+ fprintf(stderr, "Control socket initialization failed. Invalid address %s:%s?\n",
+ control_host, control_port);
+ exit(EXIT_FAILURE);
+ }
+
+ freeaddrinfo(result);
+}
+
+/* Free resources */
+void control_cleanup(void)
+{
+ close(control_fd);
+ control_fd = -1;
+}
+
+/* Write a line to the control socket */
+void control_writeln(const char *str)
+{
+ ssize_t len = strlen(str);
+ ssize_t ret;
+
+ timeout_begin(TIMEOUT);
+
+ do {
+ ret = send(control_fd, str, len, MSG_MORE);
+ timeout_check("send");
+ } while (ret < 0 && errno == EINTR);
+
+ if (ret != len) {
+ perror("send");
+ exit(EXIT_FAILURE);
+ }
+
+ do {
+ ret = send(control_fd, "\n", 1, 0);
+ timeout_check("send");
+ } while (ret < 0 && errno == EINTR);
+
+ if (ret != 1) {
+ perror("send");
+ exit(EXIT_FAILURE);
+ }
+
+ timeout_end();
+}
+
+/* Return the next line from the control socket (without the trailing newline).
+ *
+ * The program terminates if a timeout occurs.
+ *
+ * The caller must free() the returned string.
+ */
+char *control_readln(void)
+{
+ char *buf = NULL;
+ size_t idx = 0;
+ size_t buflen = 0;
+
+ timeout_begin(TIMEOUT);
+
+ for (;;) {
+ ssize_t ret;
+
+ if (idx >= buflen) {
+ char *new_buf;
+
+ new_buf = realloc(buf, buflen + 80);
+ if (!new_buf) {
+ perror("realloc");
+ exit(EXIT_FAILURE);
+ }
+
+ buf = new_buf;
+ buflen += 80;
+ }
+
+ do {
+ ret = recv(control_fd, &buf[idx], 1, 0);
+ timeout_check("recv");
+ } while (ret < 0 && errno == EINTR);
+
+ if (ret == 0) {
+ fprintf(stderr, "unexpected EOF on control socket\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (ret != 1) {
+ perror("recv");
+ exit(EXIT_FAILURE);
+ }
+
+ if (buf[idx] == '\n') {
+ buf[idx] = '\0';
+ break;
+ }
+
+ idx++;
+ }
+
+ timeout_end();
+
+ return buf;
+}
+
+/* Wait until a given line is received or a timeout occurs */
+void control_expectln(const char *str)
+{
+ char *line;
+
+ line = control_readln();
+ if (strcmp(str, line) != 0) {
+ fprintf(stderr, "expected \"%s\" on control socket, got \"%s\"\n",
+ str, line);
+ exit(EXIT_FAILURE);
+ }
+
+ free(line);
+}