X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=dccp_send.c;h=304a42e749a647d5d6a568ae0e9850d183907979;hp=d2f81dd9168023df27a1fefdb883e3234382c1cc;hb=fa578bf1d070161cafcbcc69ca7b810414ee1a4b;hpb=383d1bfb5084ea5a475e408d3cc9d2e2a3de5b88 diff --git a/dccp_send.c b/dccp_send.c index d2f81dd9..304a42e7 100644 --- a/dccp_send.c +++ b/dccp_send.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2006-2009 Andre Noll + * Copyright (C) 2006-2011 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -24,19 +24,21 @@ #include "server.h" #include "net.h" #include "list.h" -#include "vss.h" #include "send.h" +#include "vss.h" #include "fd.h" #include "close_on_fork.h" #include "chunk_queue.h" #include "server.cmdline.h" #include "acl.h" -/** Do not write more than that many bytes at once. */ -#define DCCP_MAX_BYTES_PER_WRITE 1024 - static struct sender_status dccp_sender_status, *dss = &dccp_sender_status; +struct dccp_fec_client { + struct fec_client_parms fcp; + struct fec_client *fc; +}; + static void dccp_pre_select(int *max_fileno, fd_set *rfds, __a_unused fd_set *wfds) { @@ -44,40 +46,107 @@ static void dccp_pre_select(int *max_fileno, fd_set *rfds, para_fd_set(dss->listen_fd, rfds, max_fileno); } -static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds) +/** + * Query the TX CCID used on the sender-client half connection. + * \param sockfd Server socket descriptor to query (after accept(2)). + * \return CCID number > 0, -1 on error/incompatibility. + * + * NB: This feature is only available on Linux > 2.6.30; on older kernels + * ENOPROTOOPT ("Protocol not available") will be returned. + */ +static int dccp_get_tx_ccid(int sockfd) { - struct sender_client *sc; + int tx_ccid; + socklen_t len = sizeof(tx_ccid); + + if (getsockopt(sockfd, SOL_DCCP, + DCCP_SOCKOPT_TX_CCID, &tx_ccid, &len) < 0) { + PARA_WARNING_LOG("DCCP_SOCKOPT_TX_CCID: %s\n", strerror(errno)); + return -1; + } + return tx_ccid; +} - if (dss->listen_fd < 0 || !FD_ISSET(dss->listen_fd, rfds)) - return; - sc = accept_sender_client(dss); - if (!sc) - return; - /* - * Bypass unused CCID paths: the sender does not receive application data - * from the client; by shutting down this unused communication path we can - * reduce processing costs a bit. See analogous comment in dccp_recv.c. - */ - if (shutdown(sc->fd, SHUT_RD) >= 0) - return; - PARA_WARNING_LOG("%s\n", strerror(errno)); +static void dccp_shutdown_client(struct sender_client *sc) +{ + struct dccp_fec_client *dfc = sc->private_data; + + vss_del_fec_client(dfc->fc); shutdown_client(sc, dss); } -static void dccp_send(long unsigned current_chunk, - __a_unused long unsigned chunks_sent, const char *buf, - size_t len, const char *header_buf, size_t header_len) +static void dccp_shutdown_clients(void) { struct sender_client *sc, *tmp; list_for_each_entry_safe(sc, tmp, &dss->client_list, node) - send_chunk(sc, dss, DCCP_MAX_BYTES_PER_WRITE, current_chunk, buf, - len, header_buf, header_len); + dccp_shutdown_client(sc); } -static void dccp_shutdown_clients(void) +/** * Obtain current MPS according to RFC 4340, sec. 14. */ +static int dccp_init_fec(struct sender_client *sc) { - shutdown_clients(dss); + int mps, ret; + socklen_t ml = sizeof(mps); + + /* If call fails, return some sensible minimum value */ + ret = getsockopt(sc->fd, SOL_DCCP, DCCP_SOCKOPT_GET_CUR_MPS, &mps, &ml); + if (ret < 0) { + PARA_NOTICE_LOG("can not determine MPS: %s\n", strerror(errno)); + mps = generic_max_transport_msg_size(sc->fd) - DCCP_MAX_HEADER; + } + PARA_INFO_LOG("current MPS = %d bytes\n", mps); + assert(mps > 0); + if (conf.dccp_max_slice_size_arg > 0) + mps = PARA_MIN(mps, conf.dccp_max_slice_size_arg); + return mps; +} + +static int dccp_send_fec(struct sender_client *sc, char *buf, size_t len) +{ + int ret = write_nonblock(sc->fd, buf, len); + + if (ret < 0) + dccp_shutdown_client(sc); + return ret; +} + +static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds) +{ + struct sender_client *sc; + struct dccp_fec_client *dfc; + int tx_ccid; + + sc = accept_sender_client(dss, rfds); + if (!sc) + return; + + /* If CCID identifiable, present client as #~ */ + tx_ccid = dccp_get_tx_ccid(sc->fd); + if (tx_ccid != -1) { + char *tmp = make_message("%s~%d", sc->name, tx_ccid); + + free(sc->name); + sc->name = tmp; + } + /* + * Bypass unused CCID paths: the sender does not receive application data + * from the client; by shutting down this unused communication path we can + * reduce processing costs a bit. See analogous comment in dccp_recv.c. + */ + if (shutdown(sc->fd, SHUT_RD) < 0) { + PARA_WARNING_LOG("%s\n", strerror(errno)); + shutdown_client(sc, dss); + return; + } + dfc = para_calloc(sizeof(*dfc)); + sc->private_data = dfc; + dfc->fcp.data_slices_per_group = conf.dccp_data_slices_per_group_arg; + dfc->fcp.slices_per_group = conf.dccp_slices_per_group_arg; + dfc->fcp.init_fec = dccp_init_fec; + dfc->fcp.send_fec = dccp_send_fec; + dfc->fcp.need_periodic_header = false; + dfc->fc = vss_add_fec_client(sc, &dfc->fcp); } static int dccp_com_on(__a_unused struct sender_command_data *scd) @@ -87,6 +156,7 @@ static int dccp_com_on(__a_unused struct sender_command_data *scd) static int dccp_com_off(__a_unused struct sender_command_data *scd) { + dccp_shutdown_clients(); generic_com_off(dss); return 1; } @@ -104,9 +174,34 @@ static int dccp_com_allow(struct sender_command_data *scd) return 1; } +/** + * Return list of available CCIDs or warning, in static buffer. + */ +static const char *dccp_list_available_ccids(void) +{ + /* Worst case length: n * 3 digits + n-1 spaces + '\0' */ + static char list[DCCP_MAX_HOST_CCIDS * 4]; + uint8_t *ccids; + int i, len, nccids; + + nccids = dccp_available_ccids(&ccids); + if (nccids < 0) { + snprintf(list, sizeof(list), "Unable to query available CCIDs"); + } else { + for (i = len = 0; i < nccids; i++) + len += snprintf(list + len, sizeof(list) - len, + "%s%d", i ? " " : "", ccids[i]); + } + return list; +} + static char *dccp_info(void) { - return get_sender_info(dss, "dccp"); + char *info = get_sender_info(dss, "dccp"); + char *ret = make_message("%s" "\tsupported ccids: %s\n", + info, dccp_list_available_ccids()); + free(info); + return ret; } /** @@ -119,13 +214,14 @@ static char *dccp_info(void) */ void dccp_send_init(struct sender *s) { - int ret; + int ret, k, n; s->info = dccp_info; - s->send = dccp_send; + s->send = NULL; s->pre_select = dccp_pre_select; s->post_select = dccp_post_select; s->shutdown_clients = dccp_shutdown_clients; + s->resolve_target = NULL; s->help = generic_sender_help; s->client_cmds[SENDER_ON] = dccp_com_on; s->client_cmds[SENDER_OFF] = dccp_com_off; @@ -134,6 +230,15 @@ void dccp_send_init(struct sender *s) s->client_cmds[SENDER_ADD] = NULL; s->client_cmds[SENDER_DELETE] = NULL; + k = conf.dccp_data_slices_per_group_arg; + n = conf.dccp_slices_per_group_arg; + + if (k <= 0 || n <= 0 || k >= n) { + PARA_WARNING_LOG("invalid FEC parameters, using defaults\n"); + conf.dccp_data_slices_per_group_arg = 3; + conf.dccp_slices_per_group_arg = 4; + } + init_sender_status(dss, conf.dccp_access_arg, conf.dccp_access_given, conf.dccp_port_arg, conf.dccp_max_clients_arg, conf.dccp_default_deny_given);