Run include-what-you-use.
[cubemap] / stream.cpp
index ab10e35..425477c 100644 (file)
@@ -1,18 +1,23 @@
+#include <assert.h>
 #include <errno.h>
-#include <stdio.h>
+#include <netinet/in.h>
 #include <stdlib.h>
-#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
 #include <string>
 #include <vector>
 
+#include "log.h"
+#include "metacube.h"
 #include "state.pb.h"
 #include "stream.h"
 #include "util.h"
 
 using namespace std;
 
-Stream::Stream(const string &stream_id, size_t backlog_size)
-       : stream_id(stream_id),
+Stream::Stream(const string &url, size_t backlog_size, Encoding encoding)
+       : url(url),
+         encoding(encoding),
          data_fd(make_tempfile("")),
           backlog_size(backlog_size),
          bytes_received(0),
@@ -26,20 +31,16 @@ Stream::Stream(const string &stream_id, size_t backlog_size)
 Stream::~Stream()
 {
        if (data_fd != -1) {
-               int ret;
-               do {
-                       ret = close(data_fd);
-               } while (ret == -1 && errno == EINTR);
-               if (ret == -1) {
-                       perror("close");
-               }
+               safe_close(data_fd);
        }
 }
 
-Stream::Stream(const StreamProto &serialized)
-       : stream_id(serialized.stream_id()),
-         header(serialized.header()),
-         data_fd(make_tempfile(serialized.data())),
+Stream::Stream(const StreamProto &serialized, int data_fd)
+       : url(serialized.url()),
+         http_header(serialized.http_header()),
+         stream_header(serialized.stream_header()),
+         encoding(Stream::STREAM_ENCODING_RAW),  // Will be changed later.
+         data_fd(data_fd),
          backlog_size(serialized.backlog_size()),
          bytes_received(serialized.bytes_received()),
          mark_pool(NULL)
@@ -47,18 +48,30 @@ Stream::Stream(const StreamProto &serialized)
        if (data_fd == -1) {
                exit(1);
        }
+
+       // Split old-style headers into HTTP and video headers.
+       if (!serialized.header().empty()) {
+               string header = serialized.header();
+               size_t split = header.find("\r\n\r\n");
+               if (split == string::npos) {
+                       http_header = header;
+                       stream_header = "";
+               } else {
+                       http_header = header.substr(0, split + 2);  // Split off the second \r\n.
+                       stream_header = header.substr(split, string::npos);
+               }
+       }
 }
 
 StreamProto Stream::serialize()
 {
        StreamProto serialized;
-       serialized.set_header(header);
-       if (!read_tempfile(data_fd, serialized.mutable_data())) {  // Closes data_fd.
-               exit(1);
-       }
+       serialized.set_http_header(http_header);
+       serialized.set_stream_header(stream_header);
+       serialized.add_data_fds(data_fd);
        serialized.set_backlog_size(backlog_size);
        serialized.set_bytes_received(bytes_received);
-       serialized.set_stream_id(stream_id);
+       serialized.set_url(url);
        data_fd = -1;
        return serialized;
 }
@@ -70,7 +83,7 @@ void Stream::set_backlog_size(size_t new_size)
        }
 
        string existing_data;
-       if (!read_tempfile(data_fd, &existing_data)) {  // Closes data_fd.
+       if (!read_tempfile_and_close(data_fd, &existing_data)) {
                exit(1);
        }
 
@@ -91,11 +104,20 @@ void Stream::set_backlog_size(size_t new_size)
 
        // Create a new, empty data file.
        data_fd = make_tempfile("");
+       if (data_fd == -1) {
+               exit(1);
+       }
        backlog_size = new_size;
 
        // Now cheat a bit by rewinding, and adding all the old data back.
        bytes_received -= existing_data.size();
-       add_data(existing_data.data(), existing_data.size());
+       iovec iov;
+       iov.iov_base = const_cast<char *>(existing_data.data());
+       iov.iov_len = existing_data.size();
+
+       vector<iovec> iovs;
+       iovs.push_back(iov);
+       add_data_raw(iovs);
 }
 
 void Stream::put_client_to_sleep(Client *client)
@@ -103,49 +125,121 @@ void Stream::put_client_to_sleep(Client *client)
        sleeping_clients.push_back(client);
 }
 
-void Stream::add_data(const char *data, ssize_t bytes)
+// Return a new set of iovecs that contains only the first <bytes_wanted> bytes of <data>.
+vector<iovec> collect_iovecs(const vector<iovec> &data, size_t bytes_wanted)
 {
-       size_t pos = bytes_received % backlog_size;
-       bytes_received += bytes;
-
-       if (pos + bytes > backlog_size) {
-               ssize_t to_copy = backlog_size - pos;
-               while (to_copy > 0) {
-                       int ret = pwrite(data_fd, data, to_copy, pos);
-                       if (ret == -1 && errno == EINTR) {
-                               continue;
-                       }
-                       if (ret == -1) {
-                               perror("pwrite");
-                               // Dazed and confused, but trying to continue...
-                               break;
-                       }
-                       pos += ret;
-                       data += ret;
-                       to_copy -= ret;
-                       bytes -= ret;
+       vector<iovec> ret;
+       for (size_t i = 0; i < data.size() && bytes_wanted > 0; ++i) {
+               if (data[i].iov_len <= bytes_wanted) {
+                       // Consume the entire iovec.
+                       ret.push_back(data[i]);
+                       bytes_wanted -= data[i].iov_len;
+               } else {
+                       // Take only parts of this iovec.
+                       iovec iov;
+                       iov.iov_base = data[i].iov_base;
+                       iov.iov_len = bytes_wanted;     
+                       ret.push_back(iov);
+                       bytes_wanted = 0;
                }
-               pos = 0;
        }
+       return ret;
+}
 
-       while (bytes > 0) {
-               int ret = pwrite(data_fd, data, bytes, pos);
-               if (ret == -1 && errno == EINTR) {
-                       continue;
+// Return a new set of iovecs that contains all of <data> except the first <bytes_wanted> bytes.
+vector<iovec> remove_iovecs(const vector<iovec> &data, size_t bytes_wanted)
+{
+       vector<iovec> ret;
+       size_t i;
+       for (i = 0; i < data.size() && bytes_wanted > 0; ++i) {
+               if (data[i].iov_len <= bytes_wanted) {
+                       // Consume the entire iovec.
+                       bytes_wanted -= data[i].iov_len;
+               } else {
+                       // Take only parts of this iovec.
+                       iovec iov;
+                       iov.iov_base = reinterpret_cast<char *>(data[i].iov_base) + bytes_wanted;
+                       iov.iov_len = data[i].iov_len - bytes_wanted;
+                       ret.push_back(iov);
+                       bytes_wanted = 0;
                }
+       }
+
+       // Add the rest of the iovecs unchanged.
+       ret.insert(ret.end(), data.begin() + i, data.end());
+       return ret;
+}
+
+void Stream::add_data_raw(const vector<iovec> &orig_data)
+{
+       vector<iovec> data = orig_data;
+       while (!data.empty()) {
+               size_t pos = bytes_received % backlog_size;
+
+               // Collect as many iovecs as we can before we hit the point
+               // where the circular buffer wraps around.
+               vector<iovec> to_write = collect_iovecs(data, backlog_size - pos);
+               ssize_t ret;
+               do {
+                       ret = pwritev(data_fd, to_write.data(), to_write.size(), pos);
+               } while (ret == -1 && errno == EINTR);
+
                if (ret == -1) {
-                       perror("pwrite");
+                       log_perror("pwrite");
                        // Dazed and confused, but trying to continue...
-                       break;
+                       return;
                }
-               pos += ret;
-               data += ret;
-               bytes -= ret;
+               bytes_received += ret;
+
+               // Remove the data that was actually written from the set of iovecs.
+               data = remove_iovecs(data, ret);
+       }
+}
+
+void Stream::add_data_deferred(const char *data, size_t bytes)
+{
+       if (encoding == Stream::STREAM_ENCODING_METACUBE) {
+               // Add a Metacube block header before the data.
+               metacube_block_header hdr;
+               memcpy(hdr.sync, METACUBE_SYNC, sizeof(hdr.sync));
+               hdr.size = htonl(bytes);
+               hdr.flags = htonl(0);
+
+               iovec iov;
+               iov.iov_base = new char[bytes + sizeof(hdr)];
+               iov.iov_len = bytes + sizeof(hdr);
+
+               memcpy(iov.iov_base, &hdr, sizeof(hdr));
+               memcpy(reinterpret_cast<char *>(iov.iov_base) + sizeof(hdr), data, bytes);
+
+               queued_data.push_back(iov);
+       } else if (encoding == Stream::STREAM_ENCODING_RAW) {
+               // Just add the data itself.
+               iovec iov;
+               iov.iov_base = new char[bytes];
+               memcpy(iov.iov_base, data, bytes);
+               iov.iov_len = bytes;
+
+               queued_data.push_back(iov);
+       } else {
+               assert(encoding == Stream::STREAM_ENCODING_RAW);
        }
 }
 
-void Stream::wake_up_all_clients()
+void Stream::process_queued_data()
 {
+       if (queued_data.empty()) {
+               return;
+       }
+
+       add_data_raw(queued_data);
+       for (size_t i = 0; i < queued_data.size(); ++i) {
+               char *data = reinterpret_cast<char *>(queued_data[i].iov_base);
+               delete[] data;
+       }
+       queued_data.clear();
+
+       // We have more data, so wake up all clients.
        if (to_process.empty()) {
                swap(sleeping_clients, to_process);
        } else {