Adding upstream version 0.2.0.

Signed-off-by: Daniel Baumann <daniel@debian.org>

examples/sender.c

@@ -0,0 +1,169 @@
+#include <dnswire/writer.h>
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include "create_dnstap.c"
+
+int main(int argc, const char* argv[])
+{
+    if (argc < 2) {
+        fprintf(stderr, "usage: sender [ <IP> <port> | <unix socket path> ]\n");
+        return 1;
+    }
+
+    /*
+     * We first initialize the writer and check that it can allocate the
+     * buffers it needs.
+     */
+
+    struct dnswire_writer writer;
+
+    if (dnswire_writer_init(&writer) != dnswire_ok) {
+        fprintf(stderr, "Unable to initialize dnswire writer\n");
+        return 1;
+    }
+
+    /*
+     * Use bidirectional communication over the TCP or UNIX socket.
+     */
+    if (dnswire_writer_set_bidirectional(&writer, true) != dnswire_ok) {
+        fprintf(stderr, "Unable to set dnswire writer to bidirectional mode\n");
+        return 1;
+    }
+
+    int sockfd;
+
+    if (argc == 2) {
+        /*
+         * We setup and connect to a unix socket at the given path on command line.
+         */
+
+        struct sockaddr_un path;
+
+        memset(&path, 0, sizeof(struct sockaddr_un));
+        path.sun_family = AF_UNIX;
+        strncpy(path.sun_path, argv[1], sizeof(path.sun_path) - 1);
+
+        sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
+        if (sockfd == -1) {
+            fprintf(stderr, "socket() failed: %s\n", strerror(errno));
+            return 1;
+        }
+        printf("socket\n");
+
+        if (connect(sockfd, (struct sockaddr*)&path, sizeof(struct sockaddr_un))) {
+            fprintf(stderr, "connect() failed: %s\n", strerror(errno));
+            close(sockfd);
+            return 1;
+        }
+        printf("connect\n");
+    } else {
+        /*
+         * We setup and connect to the IP and port given on command line.
+         */
+
+        struct sockaddr_storage addr_store;
+        struct sockaddr_in*     addr = (struct sockaddr_in*)&addr_store;
+        socklen_t               addrlen;
+
+        if (strchr(argv[1], ':')) {
+            addr->sin_family = AF_INET6;
+            addrlen          = sizeof(struct sockaddr_in6);
+        } else {
+            addr->sin_family = AF_INET;
+            addrlen          = sizeof(struct sockaddr_in);
+        }
+
+        if (inet_pton(addr->sin_family, argv[1], &addr->sin_addr) != 1) {
+            fprintf(stderr, "inet_pton(%s) failed: %s\n", argv[1], strerror(errno));
+            return 1;
+        }
+
+        addr->sin_port = ntohs(atoi(argv[2]));
+
+        sockfd = socket(addr->sin_family, SOCK_STREAM, IPPROTO_TCP);
+        if (sockfd == -1) {
+            fprintf(stderr, "socket() failed: %s\n", strerror(errno));
+            return 1;
+        }
+        printf("socket\n");
+
+        if (connect(sockfd, (struct sockaddr*)addr, addrlen)) {
+            fprintf(stderr, "connect() failed: %s\n", strerror(errno));
+            close(sockfd);
+            return 1;
+        }
+        printf("connect\n");
+    }
+
+    /*
+     * We are now connected!
+     *
+     * Now we create a DNSTAP message.
+     */
+
+    struct dnstap d = create_dnstap("sender");
+
+    /*
+     * We set the DNSTAP message the writer should write.
+     */
+
+    dnswire_writer_set_dnstap(writer, &d);
+
+    /*
+     * We now loop and wait for the DNSTAP message to be written.
+     */
+
+    int done = 0;
+
+    printf("sending...\n");
+    while (!done) {
+        switch (dnswire_writer_write(&writer, sockfd)) {
+        case dnswire_ok:
+            /*
+             * The DNSTAP message was written successfully, we can now set
+             * a new DNSTAP message for the writer or stop the stream.
+             *
+             * This stops the stream, loop again until it's stopped.
+             */
+            if (dnswire_writer_stop(&writer) != dnswire_ok) {
+                printf("stopping failed!\n");
+                done = 1;
+            }
+            break;
+        case dnswire_again:
+            /*
+             * This indicates that we need to call the writer again as it
+             * will only do one pass in a non-blocking fasion.
+             */
+            break;
+        case dnswire_endofdata:
+            /*
+             * The stream is stopped, we're done!
+             */
+            printf("stopped\n");
+            done = 1;
+            break;
+        default:
+            fprintf(stderr, "dnswire_writer_write() error\n");
+            done = 1;
+        }
+    }
+
+    dnswire_writer_destroy(writer);
+
+    /*
+     * Time to exit, let's shutdown and close the sockets.
+     */
+
+    shutdown(sockfd, SHUT_RDWR);
+    close(sockfd);
+
+    return 0;
+}