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 <sys/types.h>
  15 #include <dirent.h>
  16
  17 #include "para.h"
  18 #include "error.h"
  19 #include "list.h"
  20 #include "sched.h"
  21 #include "ggo.h"
  22 #include "recv.h"
  23 #include "string.h"
  24 #include "net.h"
  25 #include "fd.h"
  26
  27 #include "dccp_recv.cmdline.h"
  28
  29 /** the size of the output buffer */
  30 #define DCCP_BUFSIZE 40960
  31
  32 /**
  33  * data specific to the dccp receiver
  34  *
  35  * \sa receiver receiver_node
  36  */
  37 struct private_dccp_recv_data {
  38         /** the file descriptor for the dccp socket */
  39         int fd;
  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         free(rn->buf);
  51         rn->buf = NULL;
  52         free(rn->private_data);
  53         rn->private_data = NULL;
  54 }
  55
  56
  57 static int dccp_recv_open(struct receiver_node *rn)
  58 {
  59         struct private_dccp_recv_data *pdd;
  60         struct dccp_recv_args_info *conf = rn->conf;
  61         int fd, ret = makesock(AF_UNSPEC, IPPROTO_DCCP, 0, conf->host_arg,
  62                 conf->port_arg);
  63
  64         if (ret < 0)
  65                 return ret;
  66         fd = ret;
  67         /*
  68          * Disable unused CCIDs: the receiver does not send any application
  69          * data to the server. By shutting down this unused path we reduce
  70          * internal processing costs, as the unused CCIDs (in the kernel) are
  71          * then bypassed.
  72          */
  73         if (shutdown(fd, SHUT_WR) < 0) {
  74                 ret = -ERRNO_TO_PARA_ERROR(errno);
  75                 goto err;
  76         }
  77         ret = mark_fd_nonblocking(fd);
  78         if (ret < 0)
  79                 goto err;
  80         rn->buf = para_calloc(DCCP_BUFSIZE);
  81         rn->private_data = pdd = para_calloc(sizeof(struct private_dccp_recv_data));
  82         pdd->fd = fd;
  83         return 1;
  84 err:
  85         close(fd);
  86         return ret;
  87 }
  88
  89 static void dccp_shutdown(void)
  90 {
  91         ; /* nothing to do */
  92 }
  93
  94 static void *dccp_recv_parse_config(int argc, char **argv)
  95 {
  96         struct dccp_recv_args_info *tmp = para_calloc(sizeof(struct dccp_recv_args_info));
  97
  98         if (!dccp_recv_cmdline_parser(argc, argv, tmp))
  99                 return tmp;
 100         free(tmp);
 101         return NULL;
 102 }
 103
 104 static void dccp_recv_pre_select(struct sched *s, struct task *t)
 105 {
 106         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 107         struct private_dccp_recv_data *pdd = rn->private_data;
 108
 109         t->error = 0;
 110         para_fd_set(pdd->fd, &s->rfds, &s->max_fileno);
 111 }
 112
 113 static void dccp_recv_post_select(struct sched *s, struct task *t)
 114 {
 115         struct receiver_node *rn = container_of(t, struct receiver_node, task);
 116         struct private_dccp_recv_data *pdd = rn->private_data;
 117
 118         if (rn->output_error && *rn->output_error < 0) {
 119                 t->error = *rn->output_error;
 120                 return;
 121         }
 122         if (!FD_ISSET(pdd->fd, &s->rfds))
 123                 return; /* nothing to do */
 124         if (rn->loaded >= DCCP_BUFSIZE) {
 125                 t->error = -E_DCCP_OVERRUN;
 126                 return;
 127         }
 128         t->error = recv_bin_buffer(pdd->fd, rn->buf + rn->loaded,
 129                 DCCP_BUFSIZE - rn->loaded);
 130         if (t->error > 0) {
 131                 rn->loaded += t->error;
 132                 return;
 133         }
 134         if (!t->error)
 135                 t->error = -E_RECV_EOF;
 136 }
 137
 138 /**
 139  * The init function of the dccp receiver.
 140  *
 141  * \param r Pointer to the receiver struct to initialize.
 142  *
 143  * Initialize all function pointers of \a r.
 144  */
 145 void dccp_recv_init(struct receiver *r)
 146 {
 147         struct dccp_recv_args_info dummy;
 148
 149         dccp_recv_cmdline_parser_init(&dummy);
 150         r->shutdown = dccp_shutdown;
 151         r->open = dccp_recv_open;
 152         r->close = dccp_recv_close;
 153         r->pre_select = dccp_recv_pre_select;
 154         r->post_select = dccp_recv_post_select;
 155         r->parse_config = dccp_recv_parse_config;
 156         r->help = (struct ggo_help) {
 157                 .short_help = dccp_recv_args_info_help,
 158                 .detailed_help = dccp_recv_args_info_detailed_help
 159         };
 160 }