Add transaction log support and integrity test

[nbd.git] / nbd-server.c

diff --git a/nbd-server.c b/nbd-server.c
index 4122cef..6c3953d 100644 (file)
--- a/nbd-server.c
+++ b/nbd-server.c
@@ -213,6 +213,7 @@ typedef struct {
                                  disconnects */
        gchar* servename;    /**< name of the export as selected by nbd-client */
        int max_connections; /**< maximum number of opened connections */
+       gchar* transactionlog;/**< filename for transaction log */
 } SERVER;
 
 /**
@@ -239,6 +240,7 @@ typedef struct {
        u32 difffilelen;     /**< number of pages in difffile */
        u32 *difmap;         /**< see comment on the global difmap for this one */
        gboolean modern;     /**< client was negotiated using modern negotiation protocol */
+       int transactionlogfd;/**< fd for transaction log */
 } CLIENT;
 
 /**
@@ -582,6 +584,8 @@ void remove_server(gpointer s) {
                g_free(server->prerun);
        if(server->postrun)
                g_free(server->postrun);
+       if(server->transactionlog)
+               g_free(server->transactionlog);
        g_free(server);
 }
 
@@ -621,6 +625,9 @@ SERVER* dup_serve(SERVER *s) {
 
        if(s->postrun)
                serve->postrun = g_strdup(s->postrun);
+
+       if(s->transactionlog)
+               serve->transactionlog = g_strdup(s->transactionlog);
        
        if(s->servename)
                serve->servename = g_strdup(s->servename);
@@ -719,6 +726,7 @@ GArray* parse_cfile(gchar* f, GError** e) {
                { "virtstyle",  FALSE,  PARAM_STRING,   &(virtstyle),           0 },
                { "prerun",     FALSE,  PARAM_STRING,   &(s.prerun),            0 },
                { "postrun",    FALSE,  PARAM_STRING,   &(s.postrun),           0 },
+               { "transactionlog", FALSE, PARAM_STRING, &(s.transactionlog),   0 },
                { "readonly",   FALSE,  PARAM_BOOL,     &(s.flags),             F_READONLY },
                { "multifile",  FALSE,  PARAM_BOOL,     &(s.flags),             F_MULTIFILE },
                { "copyonwrite", FALSE, PARAM_BOOL,     &(s.flags),             F_COPYONWRITE },
@@ -1347,6 +1355,7 @@ CLIENT* negotiate(int net, CLIENT *client, GArray* servers) {
                                client->exportsize = OFFT_MAX;
                                client->net = net;
                                client->modern = TRUE;
+                               client->transactionlogfd = -1;
                                free(name);
                                return client;
                        }
@@ -1386,7 +1395,9 @@ CLIENT* negotiate(int net, CLIENT *client, GArray* servers) {
 }
 
 /** sending macro. */
-#define SEND(net,reply) writeit( net, &reply, sizeof( reply ));
+#define SEND(net,reply) { writeit( net, &reply, sizeof( reply )); \
+       if (client->transactionlogfd != -1) \
+               writeit(client->transactionlogfd, &reply, sizeof(reply)); }
 /** error macro. */
 #define ERROR(client,reply,errcode) { reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }
 /**
@@ -1421,6 +1432,9 @@ int mainloop(CLIENT *client) {
                printf("%d: ", i);
 #endif
                readit(client->net, &request, sizeof(request));
+               if (client->transactionlogfd != -1)
+                       writeit(client->transactionlogfd, &request, sizeof(request));
+
                request.from = ntohll(request.from);
                request.type = ntohl(request.type);
                command = request.type & NBD_CMD_MASK_COMMAND;
@@ -1508,6 +1522,8 @@ int mainloop(CLIENT *client) {
                if (command==NBD_CMD_READ) {
                        DEBUG("exp->buf, ");
                        memcpy(buf, &reply, sizeof(struct nbd_reply));
+                       if (client->transactionlogfd != -1)
+                               writeit(client->transactionlogfd, &reply, sizeof(reply));
                        p = buf + sizeof(struct nbd_reply);
                        writelen = currlen + sizeof(struct nbd_reply);
                        while(len > 0) {
@@ -1520,6 +1536,7 @@ int mainloop(CLIENT *client) {
                                DEBUG("buf->net, ");
                                writeit(client->net, buf, writelen);
                                len -= currlen;
+                               request.from += currlen;
                                currlen = (len < BUFSIZE) ? len : BUFSIZE;
                                p = buf;
                                writelen = currlen;
@@ -1658,6 +1675,15 @@ int do_run(gchar* command, gchar* file) {
  * @param client a connected client
  **/
 void serveconnection(CLIENT *client) {
+       if (client->server->transactionlog && (client->transactionlogfd == -1))
+       {
+               if (-1 == (client->transactionlogfd = open(client->server->transactionlog,
+                                                          O_WRONLY | O_CREAT,
+                                                          S_IRUSR | S_IWUSR)))
+                       g_warning("Could not open transaction log %s",
+                                 client->server->transactionlog);
+       }
+
        if(do_run(client->server->prerun, client->exportname)) {
                exit(EXIT_FAILURE);
        }
@@ -1671,6 +1697,12 @@ void serveconnection(CLIENT *client) {
 
        mainloop(client);
        do_run(client->server->postrun, client->exportname);
+
+       if (-1 != client->transactionlogfd)
+       {
+               close(client->transactionlogfd);
+               client->transactionlogfd = -1;
+       }
 }
 
 /**
@@ -1856,6 +1888,7 @@ int serveloop(GArray* servers) {
                                        client->server=serve;
                                        client->exportsize=OFFT_MAX;
                                        client->net=net;
+                                       client->transactionlogfd = -1;
                                }
                                set_peername(net, client);
                                if (!authorized_client(client)) {