dccp_recv.c

   1 /*
   2  * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file dccp_recv.c paraslash's dccp receiver */
   8
   9 /*
  10  * based on client.c of dccp-cs-0.01.tar.bz2,
  11  * (C) 2005 Ian McDonald <imcdnzl@gmail.com>
  12  */
  13
  14 #include <regex.h>
  15 #include <sys/types.h>
  16 #include <dirent.h>
  17
  18 #include "para.h"
  19 #include "error.h"
  20 #include "list.h"
  21 #include "sched.h"
  22 #include "ggo.h"
  23 #include "recv.h"
  24 #include "string.h"
  25 #include "net.h"
  26 #include "fd.h"
  27 #include "buffer_tree.h"
  28
  29 #include "dccp_recv.cmdline.h"
  30
  31 /**
  32  * data specific to the dccp receiver
  33  *
  34  * \sa receiver receiver_node
  35  */
  36 struct private_dccp_recv_data {
  37         /** the file descriptor for the dccp socket */
  38         int fd;
  39         struct btr_pool *btrp;
  40 };
  41
  42
  43 static void dccp_recv_close(struct receiver_node *rn)
  44 {
  45
  46         struct private_dccp_recv_data *pdd = rn->private_data;
  47
  48         if (pdd && pdd->fd > 0)
  49                 close(pdd->fd);
  50         btr_pool_free(pdd->btrp);
  51         free(rn->private_data);
  52         rn->private_data = NULL;
  53 }
  54
  55
  56 static int dccp_recv_open(struct receiver_node *rn)
  57 {
  58         struct private_dccp_recv_data *pdd;
  59         struct dccp_recv_args_info *conf = rn->conf;
  60         int fd, ret = para_connect_simple(IPPROTO_DCCP, conf->host_arg,
  61                                                         conf->port_arg);
  62         if (ret < 0)
  63                 return ret;
  64         fd = ret;
  65         /*
  66          * Disable unused CCIDs: the receiver does not send any application
  67          * data to the server. By shutting down this unused path we reduce
  68          * internal processing costs, as the unused CCIDs (in the kernel) are
  69          * then bypassed.
  70          */
  71         if (shutdown(fd, SHUT_WR) < 0) {
  72                 ret = -ERRNO_TO_PARA_ERROR(errno);
  73                 goto err;
  74         }
  75         ret = mark_fd_nonblocking(fd);
  76         if (ret < 0)
  77                 goto err;
  78         rn->private_data = pdd = para_calloc(sizeof(struct private_dccp_recv_data));
  79         pdd->btrp = btr_pool_new("dccp_recv", 320 * 1024);
  80         pdd->fd = fd;
  81         return 1;
  82 err:
  83         close(fd);
  84         return ret;
  85 }
  86
  87 static void *dccp_recv_parse_config(int argc, char **argv)
  88 {
  89         struct dccp_recv_args_info *tmp = para_calloc(sizeof(struct dccp_recv_args_info));
  90
  91         if (!dccp_recv_cmdline_parser(argc, argv, tmp))
  92                 return tmp;
  93         free(tmp);
  94         return NULL;
  95 }
  96
  97 static void dccp_recv_pre_select(struct sched *s, struct task *t)
  98 {
  99         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 100         struct private_dccp_recv_data *pdd = rn->private_data;
 101
 102         t->error = 0;
 103         if (generic_recv_pre_select(s, t) <= 0)
 104                 return;
 105         para_fd_set(pdd->fd, &s->rfds, &s->max_fileno);
 106 }
 107
 108 static void dccp_recv_post_select(struct sched *s, struct task *t)
 109 {
 110         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 111         struct private_dccp_recv_data *pdd = rn->private_data;
 112         struct btr_node *btrn = rn->btrn;
 113         struct iovec iov[2];
 114         int ret, iovcnt;
 115
 116         ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
 117         if (ret < 0)
 118                 goto err;
 119         if (ret == 0)
 120                 return;
 121         if (!FD_ISSET(pdd->fd, &s->rfds))
 122                 return; /* nothing to do */
 123         iovcnt = btr_pool_get_buffers(pdd->btrp, iov);
 124         ret = -E_DCCP_OVERRUN;
 125         if (iovcnt == 0)
 126                 goto err;
 127         ret = para_readv(pdd->fd, iov, iovcnt);
 128         if (ret == 0)
 129                 ret = -E_RECV_EOF;
 130         if (ret < 0)
 131                 goto err;
 132         if (ret <= iov[0].iov_len) /* only the first buffer was filled */
 133                 btr_add_output_pool(pdd->btrp, ret, btrn);
 134         else { /* both buffers contain data */
 135                 btr_add_output_pool(pdd->btrp, iov[0].iov_len, btrn);
 136                 btr_add_output_pool(pdd->btrp, ret - iov[0].iov_len, btrn);
 137         }
 138         return;
 139 err:
 140         btr_remove_node(rn->btrn);
 141         t->error = ret;
 142 }
 143
 144 static void dccp_recv_free_config(void *conf)
 145 {
 146         dccp_recv_cmdline_parser_free(conf);
 147         free(conf);
 148 }
 149
 150 /**
 151  * The init function of the dccp receiver.
 152  *
 153  * \param r Pointer to the receiver struct to initialize.
 154  *
 155  * Initialize all function pointers of \a r.
 156  */
 157 void dccp_recv_init(struct receiver *r)
 158 {
 159         struct dccp_recv_args_info dummy;
 160
 161         dccp_recv_cmdline_parser_init(&dummy);
 162         r->open = dccp_recv_open;
 163         r->close = dccp_recv_close;
 164         r->pre_select = dccp_recv_pre_select;
 165         r->post_select = dccp_recv_post_select;
 166         r->parse_config = dccp_recv_parse_config;
 167         r->free_config = dccp_recv_free_config;
 168         r->help = (struct ggo_help) {
 169                 .short_help = dccp_recv_args_info_help,
 170                 .detailed_help = dccp_recv_args_info_detailed_help
 171         };
 172         dccp_recv_cmdline_parser_free(&dummy);
 173 }