Rewrite chunk queueing.
[paraslash.git] / http_send.c
index c01c6c96e91df812a835fb83b84c0cb2122277f5..414c37530a66a6f93171fc0579dcaafd7e8f7df0 100644 (file)
 #define HTTP_ERR_MSG "HTTP/1.0 400 Bad Request\n"
 /** \endcond */
 
-/** the possible states of a client from the server's POV */
+/** The possible states of a client from the server's POV. */
 enum http_status {
+       /** We accepted the connection on the tcp socket. */
        HTTP_CONNECTED,
+       /** Successfully received the get request. */
        HTTP_GOT_GET_REQUEST,
+       /** We sent the OK message back to the client. */
        HTTP_SENT_OK_MSG,
+       /** Connection established, we might need to send the audio file header. */
        HTTP_READY_TO_STREAM,
+       /** Connection is ready for sending audio data. */
        HTTP_STREAMING,
+       /** We didn't receive a valid get request. */
        HTTP_INVALID_GET_REQUEST
 };
 
-/** clients will be kicked if there are more than that many bytes pending */
+/** Clients will be kicked if there are more than that many bytes pending. */
 #define MAX_BACKLOG 40000
-/** the list of connected clients **/
+/** The list of connected clients. */
 static struct list_head clients;
-/** the whitelist/blacklist */
+/** The whitelist/blacklist. */
 static struct list_head access_perm_list;
 
-/** describes one client that connected the tcp port of the http sender */
+/** Describes one client that connected the tcp port of the http sender. */
 struct http_client {
-/** the file descriptor of the client */
+       /** The file descriptor of the client. */
        int fd;
-/** address information about the client */
+       /** Address information about the client. */
        struct sockaddr_in addr;
-/** the client's current status */
+       /** The client's current status. */
        enum http_status status;
-/** non-zero if we included \a fd in the read set */
+       /** Non-zero if we included \a fd in the read set.*/
        int check_r;
-/** non-zero if we included \a fd in the write set */
+       /** Non-zero if we included \a fd in the write set. */
        int check_w;
-/** the position of this client in the client list */
+       /** The position of this client in the client list. */
        struct list_head node;
-/** the list of pending packets for this client */
-       struct list_head packet_queue;
-/** the number of pending bytes for this client */
-       unsigned long pq_bytes;
+       /** The list of pending chunks for this client. */
+       struct list_head chunk_queue;
+       /** The number of pending bytes for this client. */
+       unsigned long cq_bytes;
 };
 
 /**
- * describes one queued data packet for a client
+ * Describes one queued chunk of the chunk queue.
  *
  * The send function of the http sender checks each client fd for writing. If a
- * client fd is not ready, it tries to queue that packet for this client until
+ * client fd is not ready, it tries to queue that chunk for this client until
  * the number of queued bytes exceeds \p MAX_BACKLOG.
  */
-struct queued_packet {
-/** the length of the packet in bytes */
-       unsigned int len;
-/** pointer to the packet data */
-       char *packet;
-/** position of the packet in the packet list */
+struct queued_chunk {
+       /** The number of the queued chunk, -1U means header. */
+       unsigned chunk_num;
+       /** The number of bytes already sent. */
+       unsigned sent;
+       /** Position of the chunk in the chunk queue. */
        struct list_head node;
 };
 
 /**
- * describes one entry in the blacklist/whitelist of the http sender
+ * Describes one entry in the blacklist/whitelist of the http sender.
  */
 struct access_info {
-       /** the address to be black/whitelisted */
+       /** The address to be black/whitelisted. */
        struct in_addr addr;
-       /** the netmask for this entry */
+       /** The netmask for this entry. */
        unsigned netmask;
-       /** the position of this entry in the access_perm_list */
+       /** The position of this entry in the access_perm_list. */
        struct list_head node;
 };
 
 static int server_fd = -1, numclients;
 static struct sender *self;
 
-
 static void http_shutdown_client(struct http_client *hc, const char *msg)
 {
-       struct queued_packet *qp, *tmp;
+       struct queued_chunk *qc, *tmp;
        PARA_INFO_LOG("shutting down %s on fd %d (%s)\n", CLIENT_ADDR(hc),
                hc->fd, msg);
        numclients--;
        close(hc->fd);
        del_close_on_fork_list(hc->fd);
-       list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
-               free(qp->packet);
-               list_del(&qp->node);
-               free(qp);
+       list_for_each_entry_safe(qc, tmp, &hc->chunk_queue, node) {
+               list_del(&qc->node);
+               free(qc);
        }
        list_del(&hc->node);
        free(hc);
@@ -140,50 +144,74 @@ static int http_send_err_msg(struct http_client *hc)
        return http_send_msg(hc, HTTP_ERR_MSG);
 }
 
-static int queue_packet(struct http_client *hc, const char *buf, size_t len)
+static int queue_chunk(struct http_client *hc, long unsigned chunk_num,
+       size_t sent)
 {
-       struct queued_packet *qp;
-       if (hc->pq_bytes + len > MAX_BACKLOG) {
-               http_shutdown_client(hc, "packet queue overrun");
+       struct queued_chunk *qc;
+       char *buf;
+       size_t len;
+       int ret;
+
+       if (chunk_num != -1U) {
+               ret = vss_get_chunk(chunk_num, &buf, &len);
+               if (ret < 0)
+                       return ret;
+       } else
+               buf = vss_get_header(&len);
+       if (hc->cq_bytes + len > MAX_BACKLOG)
                return -E_QUEUE;
-       }
-       qp = para_malloc(sizeof(struct queued_packet));
-       hc->pq_bytes += len;
-       qp->packet = para_malloc(len);
-       memcpy(qp->packet, buf, len);
-       qp->len = len;
-       list_add_tail(&qp->node, &hc->packet_queue);
-       PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->pq_bytes, hc->fd);
+       qc = para_malloc(sizeof(struct queued_chunk));
+       hc->cq_bytes += len;
+       qc->chunk_num = chunk_num;
+       qc->sent = sent;
+       list_add_tail(&qc->node, &hc->chunk_queue);
+       PARA_INFO_LOG("%lu bytes queued for fd %d\n", hc->cq_bytes, hc->fd);
        return 1;
 }
 
-static int send_queued_packets(struct http_client *hc)
+static int send_queued_chunks(struct http_client *hc)
 {
        int ret;
-       struct queued_packet *qp, *tmp;
+       struct queued_chunk *qc, *tmp;
 
-       if (list_empty(&hc->packet_queue))
+       if (list_empty(&hc->chunk_queue))
                return 1;
-       list_for_each_entry_safe(qp, tmp, &hc->packet_queue, node) {
+       list_for_each_entry_safe(qc, tmp, &hc->chunk_queue, node) {
+               char *buf;
+               size_t len;
                ret = write_ok(hc->fd);
                if (ret <= 0)
                        return ret? -E_WRITE_OK : 0;
-               ret = write(hc->fd, qp->packet, qp->len);
+               if (qc->chunk_num != -1U) {
+                       ret = vss_get_chunk(qc->chunk_num, &buf, &len);
+                       if (ret < 0)
+                               return ret;
+               } else
+                       buf = vss_get_header(&len);
+               assert(len && len > qc->sent);
+               ret = write(hc->fd, buf + qc->sent, len - qc->sent);
                if (ret < 0)
-                       return ret;
-               if (ret != qp->len) {
-                       qp->len -= ret;
-                       memmove(qp->packet, qp->packet + ret, qp->len);
+                       return -1; /* FIXME */
+               hc->cq_bytes -= ret;
+               if (ret != len - qc->sent) {
+                       qc->sent += ret;
                        return 0;
                }
-               hc->pq_bytes -= qp->len;
-               free(qp->packet);
-               list_del(&qp->node);
-               free(qp);
+               list_del(&qc->node);
+               free(qc);
        }
        return 1;
 }
 
+static int queue_chunk_or_shutdown(struct http_client *hc, long unsigned chunk_num,
+       size_t sent)
+{
+       int ret = queue_chunk(hc, chunk_num, sent);
+       if (ret < 0)
+               http_shutdown_client(hc, "queue error");
+       return ret;
+}
+
 static void http_send( long unsigned current_chunk,
        __a_unused long unsigned chunks_sent, const char *buf, size_t len)
 {
@@ -200,34 +228,35 @@ static void http_send( long unsigned current_chunk,
                        if (hbuf && hlen > 0 && current_chunk) {
                                /* need to send header */
                                PARA_INFO_LOG("queueing header: %d\n", hlen);
-                               if (queue_packet(hc, hbuf, hlen) < 0)
+                               if (queue_chunk_or_shutdown(hc, -1U, 0) < 0)
                                        continue;
                        } else
-                               PARA_INFO_LOG("%s", "no need to queue header\n");
+                               PARA_INFO_LOG("no need to queue header\n");
                        hc->status = HTTP_STREAMING;
                }
-               ret = send_queued_packets(hc);
+               ret = send_queued_chunks(hc);
                if (ret < 0) {
-                       http_shutdown_client(hc, "send error");
+                       http_shutdown_client(hc, "queue send error");
                        continue;
                }
                if (!len)
                        continue;
                if (!ret || write_ok(hc->fd) <= 0) {
                        PARA_INFO_LOG("fd %d not ready (%lu bytes queued),"
-                               " trying to queue packet\n", hc->fd,
-                               hc->pq_bytes);
-                       queue_packet(hc, buf, len);
+                               " trying to queue chunk\n", hc->fd,
+                               hc->cq_bytes);
+                       queue_chunk_or_shutdown(hc, current_chunk, 0);
                        continue;
                }
 //             PARA_DEBUG_LOG("sending %d -> %s\n", len, CLIENT_ADDR(hc));
                ret = write(hc->fd, buf, len);
+//             PARA_DEBUG_LOG("ret: %d\n", ret);
                if (ret < 0) {
                        http_shutdown_client(hc, "send error");
                        continue;
                }
                if (ret != len)
-                       queue_packet(hc, buf + ret, len - ret);
+                       queue_chunk_or_shutdown(hc, current_chunk, ret);
        }
 }
 
@@ -307,7 +336,7 @@ static void http_post_select(fd_set *rfds, fd_set *wfds)
                goto err_out;
        }
        hc->status = HTTP_CONNECTED;
-       INIT_LIST_HEAD(&hc->packet_queue);
+       INIT_LIST_HEAD(&hc->chunk_queue);
        PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", numclients,
                CLIENT_ADDR(hc), hc->fd);
        numclients++;
@@ -518,12 +547,12 @@ static char *http_help(void)
 }
 
 /**
- * the init function of the http sender
+ * The init function of the http sender.
  *
- * \param s pointer to the http sender struct
+ * \param s Pointer to the http sender struct.
  *
- * It initializes all function pointers of \a s, init the client list and the
- * acess control list as well. If autostart is wanted, open the tcp port.
+ * It initializes all function pointers of \a s, the client list and the access
+ * control list. If the autostart option was given, the tcp port is opened.
  */
 void http_send_init(struct sender *s)
 {