+/* Write the append only file buffer on disk.
+ *
+ * Since we are required to write the AOF before replying to the client,
+ * and the only way the client socket can get a write is entering when the
+ * the event loop, we accumulate all the AOF writes in a memory
+ * buffer and write it on disk using this function just before entering
+ * the event loop again. */
+static void flushAppendOnlyFile(void) {
+ time_t now;
+ ssize_t nwritten;
+
+ if (sdslen(server.aofbuf) == 0) return;
+
+ /* We want to perform a single write. This should be guaranteed atomic
+ * at least if the filesystem we are writing is a real physical one.
+ * While this will save us against the server being killed I don't think
+ * there is much to do about the whole server stopping for power problems
+ * or alike */
+ nwritten = write(server.appendfd,server.aofbuf,sdslen(server.aofbuf));
+ if (nwritten != (signed)sdslen(server.aofbuf)) {
+ /* Ooops, we are in troubles. The best thing to do for now is
+ * aborting instead of giving the illusion that everything is
+ * working as expected. */
+ if (nwritten == -1) {
+ redisLog(REDIS_WARNING,"Exiting on error writing to the append-only file: %s",strerror(errno));
+ } else {
+ redisLog(REDIS_WARNING,"Exiting on short write while writing to the append-only file: %s",strerror(errno));
+ }
+ exit(1);
+ }
+ sdsfree(server.aofbuf);
+ server.aofbuf = sdsempty();
+
+ /* Fsync if needed */
+ now = time(NULL);
+ if (server.appendfsync == APPENDFSYNC_ALWAYS ||
+ (server.appendfsync == APPENDFSYNC_EVERYSEC &&
+ now-server.lastfsync > 1))
+ {
+ /* aof_fsync is defined as fdatasync() for Linux in order to avoid
+ * flushing metadata. */
+ aof_fsync(server.appendfd); /* Let's try to get this data on the disk */
+ server.lastfsync = now;
+ }
+}
+
+static sds catAppendOnlyGenericCommand(sds buf, int argc, robj **argv) {
+ int j;
+ buf = sdscatprintf(buf,"*%d\r\n",argc);
+ for (j = 0; j < argc; j++) {
+ robj *o = getDecodedObject(argv[j]);
+ buf = sdscatprintf(buf,"$%lu\r\n",(unsigned long)sdslen(o->ptr));
+ buf = sdscatlen(buf,o->ptr,sdslen(o->ptr));
+ buf = sdscatlen(buf,"\r\n",2);
+ decrRefCount(o);
+ }
+ return buf;
+}
+
+static sds catAppendOnlyExpireAtCommand(sds buf, robj *key, robj *seconds) {
+ int argc = 3;
+ long when;
+ robj *argv[3];
+
+ /* Make sure we can use strtol */
+ seconds = getDecodedObject(seconds);
+ when = time(NULL)+strtol(seconds->ptr,NULL,10);
+ decrRefCount(seconds);
+
+ argv[0] = createStringObject("EXPIREAT",8);
+ argv[1] = key;
+ argv[2] = createObject(REDIS_STRING,
+ sdscatprintf(sdsempty(),"%ld",when));
+ buf = catAppendOnlyGenericCommand(buf, argc, argv);
+ decrRefCount(argv[0]);
+ decrRefCount(argv[2]);
+ return buf;
+}
+
projects / redis.git / blobdiff