Serving more than one image.

3 files changed, 170 insertions, 14 deletions

diff --git a/src/server/hashtable.c b/src/server/hashtable.c
new file mode 100644
index 0000000..518454f
--- /dev/null
+++ b/src/server/hashtable.c
@@ -0,0 +1,70 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include <stdio.h>
+#include <search.h>
+#include <string.h>
+
+#include "../config.h"
+
+char key_buf[MAX_NUMBER_IMAGES * MAX_FILE_ID];
+char value_buf[MAX_NUMBER_IMAGES * MAX_FILE_NAME];
+
+char *key_ptr = key_buf;
+char *val_ptr = value_buf;
+
+void ht_create()
+{
+	(void) hcreate(MAX_NUMBER_IMAGES);
+}
+
+int ht_insert(char* key, char* value)
+{
+	if (strlen(key) > MAX_FILE_ID) return -1;
+	if (strlen(value) > MAX_FILE_NAME) return -2;
+
+	strcpy(key_ptr, key);
+	strcpy(val_ptr, value);
+
+	ENTRY item;
+	item.key = key_ptr;
+	item.data = val_ptr;
+
+	(void) hsearch(item, ENTER);
+
+	key_ptr += strlen(key) + 1;
+	val_ptr += strlen(value) + 1;
+
+	return 0;
+}
+
+char* ht_search(char* key)
+{
+	ENTRY *result;
+
+	ENTRY item;
+	item.key = key;
+
+	if ((result = hsearch(item, FIND)) != NULL)
+		return result->data;
+	else
+		return NULL;
+}
+
diff --git a/src/server/hashtable.h b/src/server/hashtable.h
new file mode 100644
index 0000000..c05d459
--- /dev/null
+++ b/src/server/hashtable.h
@@ -0,0 +1,30 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef HASHTABLE_H_
+#define HASHTABLE_H_
+
+void ht_create ();
+
+int ht_insert(char* key, char* value);
+
+char* ht_search(char* key);
+
+#endif /* HASHTABLE_H_ */
diff --git a/src/server/server.c b/src/server/server.c
index 7f62a53..7185e2f 100644
--- a/src/server/server.c
+++ b/src/server/server.c
@@ -1,3 +1,23 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -19,17 +39,16 @@
 #include "../types.h"
 #include "../version.h"
 
-int file;
-off_t filesize;
+#include "hashtable.h"
 
 void print_help(char* argv_0)
 {
 
 	printf("Usage: %s [OPTIONS]...\n", argv_0);
-	printf("Start the DNBD3 server.\n");
-	printf("-f or --file \t\t File to export.\n");
-	printf("-h or --help \t\t Show this help text and quit.\n");
-	printf("-v or --version \t Show version and quit.\n");
+	printf("Start the DNBD3 server\n");
+	printf("-f or --file \t\t Configuration file\n \t\t\t (default /etc/dnbd3-server.conf)\n");
+	printf("-h or --help \t\t Show this help text and quit\n");
+	printf("-v or --version \t Show version and quit\n");
 	exit(0);
 }
 
@@ -47,6 +66,8 @@ void handle_sigpipe(int signum)
 
 void *handle_query(void *client_socket)
 {
+	int image_file = -1;
+	off_t filesize = 0;
 	int sock = (int) client_socket;
 	struct dnbd3_request request;
 	struct dnbd3_reply reply;
@@ -58,23 +79,40 @@ void *handle_query(void *client_socket)
 		switch (cmd)
 		{
 		case CMD_GET_SIZE:
+			image_file = open(ht_search(request.image_id), O_RDONLY);
+			if (image_file < 0)
+			{
+				printf("ERROR: Client requested an unknown image id.\n");
+				filesize = 0;
+			}
+			else
+			{
+				struct stat st;
+				fstat(image_file, &st);
+				filesize = st.st_size;
+			}
+
 			reply.cmd = request.cmd;
 			reply.filesize = filesize;
 			send(sock, (char *) &reply, sizeof(struct dnbd3_reply), 0);
 			break;
 
 		case CMD_GET_BLOCK:
+			if (image_file < 0)
+				break;
+
 			reply.cmd = request.cmd;
 			memcpy(reply.handle, request.handle, sizeof(request.handle));
 			send(sock, (char *) &reply, sizeof(struct dnbd3_reply), 0);
 
-			if (sendfile(sock, file, (off_t *) &request.offset, request.size) <0)
+			if (sendfile(sock, image_file, (off_t *) &request.offset, request.size) <0)
 				printf("ERROR: sendfile returned -1\n");
 
 			break;
 
 		default:
 			printf("ERROR: Unknown command\n");
+			break;
 		}
 
 	}
@@ -85,6 +123,8 @@ void *handle_query(void *client_socket)
 
 int main(int argc, char* argv[])
 {
+	char *config_file_name = DEFAULT_CONFIG_FILE;
+
 	int opt = 0;
 	int longIndex = 0;
 	static const char *optString = "f:hv?";
@@ -95,18 +135,13 @@ int main(int argc, char* argv[])
 	{ "version", no_argument, NULL, 'v' } };
 
 	opt = getopt_long(argc, argv, optString, longOpts, &longIndex);
-	if (opt == -1)
-		print_help(argv[0]);
 
 	while (opt != -1)
 	{
 		switch (opt)
 		{
 		case 'f':
-			file = open(optarg, O_RDONLY);
-			struct stat st;
-			fstat(file, &st);
-			filesize = st.st_size;
+			config_file_name = optarg;
 			break;
 		case 'h':
 			print_help(argv[0]);
@@ -120,6 +155,28 @@ int main(int argc, char* argv[])
 		opt = getopt_long(argc, argv, optString, longOpts, &longIndex);
 	}
 
+	// parse config file
+	ht_create();
+	FILE *config_file = fopen(config_file_name , "r");
+	if (config_file == NULL)
+	{
+		printf("ERROR: Config file not found: %s\n", config_file_name);
+		exit(EXIT_FAILURE);
+	}
+	char line[MAX_FILE_NAME + 1 + MAX_FILE_ID];
+	char* image_name = NULL;
+	char* image_id = NULL;
+	while (fgets (line , sizeof(line) , config_file) != NULL )
+	{
+		sscanf (line, "%as %as", &image_name, &image_id);
+		if (ht_insert(image_id, image_name) < 0)
+		{
+			printf("ERROR: Image name or ID is too big\n");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	// setup network
 	signal(SIGPIPE, handle_sigpipe);
 
 	struct sockaddr_in server;
@@ -154,7 +211,6 @@ int main(int argc, char* argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	printf("INFO: Filesize: %llu bytes\n", filesize);
 	printf("INFO: Server is ready...\n");
 
 	while (1)