aboutsummaryrefslogtreecommitdiffstats
path: root/example/server.c
diff options
context:
space:
mode:
Diffstat (limited to 'example/server.c')
-rw-r--r--example/server.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/example/server.c b/example/server.c
new file mode 100644
index 00000000..a671f4cb
--- /dev/null
+++ b/example/server.c
@@ -0,0 +1,149 @@
+/* This is a simple TCP server that listens on port 1234 and provides lists
+ * of files to clients, using a protocol defined in file_server.proto.
+ *
+ * It directly deserializes and serializes messages from network, minimizing
+ * memory use.
+ *
+ * For flexibility, this example is implemented using posix api.
+ * In a real embedded system you would typically use some other kind of
+ * a communication and filesystem layer.
+ */
+
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <pb_encode.h>
+#include <pb_decode.h>
+
+#include "fileproto.h"
+
+bool write_callback(pb_ostream_t *stream, const uint8_t *buf, size_t count)
+{
+ int fd = *(int*)stream->state;
+ return send(fd, buf, count, 0) == count;
+}
+
+bool read_callback(pb_istream_t *stream, uint8_t *buf, size_t count)
+{
+ int fd = *(int*)stream->state;
+
+ if (buf == NULL)
+ {
+ /* Well, this is a really inefficient way to skip input. */
+ /* It is only used when there are unknown fields. */
+ char dummy;
+ while (count-- && recv(fd, &dummy, 1, 0) == 1);
+ return count == 0;
+ }
+
+ return recv(fd, buf, count, MSG_WAITALL) == count;
+}
+
+bool listdir_callback(pb_ostream_t *stream, const pb_field_t *field, const void *arg)
+{
+ DIR *dir = (DIR*) arg;
+ struct dirent *file;
+ FileInfo fileinfo;
+
+ while ((file = readdir(dir)) != NULL)
+ {
+ fileinfo.inode = file->d_ino;
+ strncpy(fileinfo.name, file->d_name, sizeof(fileinfo.name));
+ fileinfo.name[sizeof(fileinfo.name) - 1] = '\0';
+
+ if (!pb_encode_tag_for_field(stream, field))
+ return false;
+
+ if (!pb_enc_submessage(stream, field, &fileinfo))
+ return false;
+ }
+
+ return true;
+}
+
+void handle_connection(int connfd)
+{
+ ListFilesRequest request;
+ ListFilesResponse response;
+ pb_istream_t input = {&read_callback, &connfd, SIZE_MAX};
+ pb_ostream_t output = {&write_callback, &connfd, SIZE_MAX, 0};
+ DIR *directory;
+
+ if (!pb_decode(&input, ListFilesRequest_fields, &request))
+ {
+ printf("Decoding failed.\n");
+ return;
+ }
+
+ directory = opendir(request.path);
+
+ printf("Listing directory: %s\n", request.path);
+
+ if (directory == NULL)
+ {
+ perror("opendir");
+
+ response.has_path_error = true;
+ response.path_error = true;
+ response.file.funcs.encode = NULL;
+ }
+ else
+ {
+ response.has_path_error = false;
+ response.file.funcs.encode = &listdir_callback;
+ response.file.arg = directory;
+ }
+
+ if (!pb_encode(&output, ListFilesResponse_fields, &response))
+ {
+ printf("Encoding failed.\n");
+ }
+}
+
+int main(int argc, char **argv)
+{
+ int listenfd, connfd;
+ struct sockaddr_in servaddr;
+
+ listenfd = socket(AF_INET, SOCK_STREAM, 0);
+
+ memset(&servaddr, 0, sizeof(servaddr));
+ servaddr.sin_family = AF_INET;
+ servaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+ servaddr.sin_port = htons(1234);
+ if (bind(listenfd, (struct sockaddr*)&servaddr, sizeof(servaddr)) != 0)
+ {
+ perror("bind");
+ return 1;
+ }
+
+ if (listen(listenfd, 5) != 0)
+ {
+ perror("listen");
+ return 1;
+ }
+
+ for(;;)
+ {
+ connfd = accept(listenfd, NULL, NULL);
+
+ if (connfd < 0)
+ {
+ perror("accept");
+ return 1;
+ }
+
+ printf("Got connection.\n");
+
+ handle_connection(connfd);
+
+ printf("Closing connection.\n");
+
+ close(connfd);
+ }
+}