git.sesse.net Git - cubemap/blob - input.cpp

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdint.h>
   4 #include <assert.h>
   5 #include <arpa/inet.h>
   6 #include <curl/curl.h>
   7 #include <sys/socket.h>
   8 #include <pthread.h>
   9 #include <sys/types.h>
  10 #include <sys/ioctl.h>
  11 #include <sys/epoll.h>
  12 #include <errno.h>
  13 #include <vector>
  14 #include <string>
  15 #include <map>
  16
  17 #include "metacube.h"
  18 #include "mutexlock.h"
  19 #include "input.h"
  20 #include "server.h"
  21 #include "serverpool.h"
  22
  23 using namespace std;
  24
  25 extern ServerPool *servers;
  26
  27 Input::Input(const string &stream_id, const string &url)
  28         : stream_id(stream_id),
  29           url(url),
  30           has_metacube_header(false)
  31 {
  32 }
  33
  34 void Input::run()
  35 {
  36         should_stop = false;
  37
  38         // Joinable is already the default, but it's good to be certain.
  39         pthread_attr_t attr;
  40         pthread_attr_init(&attr);
  41         pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
  42         pthread_create(&worker_thread, &attr, Input::do_work_thunk, this);
  43 }
  44
  45 void Input::stop()
  46 {
  47         should_stop = true;
  48
  49         if (pthread_join(worker_thread, NULL) == -1) {
  50                 perror("pthread_join");
  51                 exit(1);
  52         }
  53 }
  54
  55 void *Input::do_work_thunk(void *arg)
  56 {
  57         Input *input = static_cast<Input *>(arg);
  58         input->do_work();
  59         return NULL;
  60 }
  61
  62 void Input::do_work()
  63 {
  64         CURL *curl = curl_easy_init();
  65
  66         while (!should_stop) {
  67                 curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
  68                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, &Input::curl_callback_thunk);
  69                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, this);
  70                 curl_easy_perform(curl);
  71                 if (!should_stop) {
  72                         printf("Transfer of '%s' ended, waiting 0.2 seconds and restarting...\n", url.c_str());
  73                         usleep(200000);
  74                 }
  75         }
  76 }
  77
  78 size_t Input::curl_callback_thunk(char *ptr, size_t size, size_t nmemb, void *userdata)
  79 {
  80         Input *input = static_cast<Input *>(userdata);
  81         if (input->should_stop) {
  82                 return 0;
  83         }
  84
  85         size_t bytes = size * nmemb;
  86         input->curl_callback(ptr, bytes);
  87         return bytes;
  88 }
  89
  90 void Input::curl_callback(char *ptr, size_t bytes)
  91 {
  92         pending_data.insert(pending_data.end(), ptr, ptr + bytes);
  93
  94         for ( ;; ) {
  95                 // If we don't have enough data (yet) for even the Metacube header, just return.
  96                 if (pending_data.size() < sizeof(metacube_block_header)) {
  97                         return;
  98                 }
  99
 100                 // Make sure we have the Metacube sync header at the start.
 101                 // We may need to skip over junk data (it _should_ not happen, though).
 102                 if (!has_metacube_header) {
 103                         char *ptr = static_cast<char *>(
 104                                 memmem(pending_data.data(), pending_data.size(),
 105                                        METACUBE_SYNC, strlen(METACUBE_SYNC)));
 106                         if (ptr == NULL) {
 107                                 // OK, so we didn't find the sync marker. We know then that
 108                                 // we do not have the _full_ marker in the buffer, but we
 109                                 // could have N-1 bytes. Drop everything before that,
 110                                 // and then give up.
 111                                 drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
 112                                 return;
 113                         } else {
 114                                 // Yay, we found the header. Drop everything (if anything) before it.
 115                                 drop_pending_data(ptr - pending_data.data());
 116                                 has_metacube_header = true;
 117
 118                                 // Re-check that we have the entire header; we could have dropped data.
 119                                 if (pending_data.size() < sizeof(metacube_block_header)) {
 120                                         return;
 121                                 }
 122                         }
 123                 }
 124
 125                 // Now it's safe to read the header.
 126                 metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
 127                 assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
 128                 uint32_t size = ntohl(hdr->size);
 129                 uint32_t flags = ntohl(hdr->flags);
 130
 131                 // See if we have the entire block. If not, wait for more data.
 132                 if (pending_data.size() < sizeof(metacube_block_header) + size) {
 133                         return;
 134                 }
 135
 136                 process_block(pending_data.data() + sizeof(metacube_block_header), size, flags);
 137
 138                 // Consume this block. This isn't the most efficient way of dealing with things
 139                 // should we have many blocks, but these routines don't need to be too efficient
 140                 // anyway.
 141                 pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
 142                 has_metacube_header = false;
 143         }
 144 }
 145
 146 void Input::process_block(const char *data, uint32_t size, uint32_t flags)
 147 {
 148         if (flags & METACUBE_FLAGS_HEADER) {
 149                 string header(data, data + size);
 150                 servers->set_header(stream_id, header);
 151         } else {
 152                 servers->add_data(stream_id, data, size);
 153         }
 154 }
 155
 156 void Input::drop_pending_data(size_t num_bytes)
 157 {
 158         if (num_bytes == 0) {
 159                 return;
 160         }
 161         fprintf(stderr, "Warning: Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?\n",
 162                 (long long)num_bytes);
 163         pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
 164 }
 165