avformat: Add AMQP version 0-9-1 protocol support

Supports connecting to a RabbitMQ broker via AMQP version 0-9-1.

Signed-off-by: Andriy Gelman <andriy.gelman@gmail.com>
Signed-off-by: Marton Balint <cus@passwd.hu>

8 files changed, 368 insertions, 1 deletions

diff --git a/Changelog b/Changelog
index 41a9166827..db2ca92e8a 100644
--- a/Changelog
+++ b/Changelog
@@ -45,6 +45,7 @@ version <next>:
 - cas video filter
 - High Voltage Software ADPCM decoder
 - LEGO Racers ALP (.tun & .pcm) demuxer
+- AMQP 0-9-1 protocol (RabbitMQ)
 
 
 version 4.2:
diff --git a/configure b/configure
index 06e3a7b2a8..8b17134944 100755
--- a/configure
+++ b/configure
@@ -255,6 +255,7 @@ External library support:
   --enable-libopenmpt      enable decoding tracked files via libopenmpt [no]
   --enable-libopus         enable Opus de/encoding via libopus [no]
   --enable-libpulse        enable Pulseaudio input via libpulse [no]
+  --enable-librabbitmq     enable RabbitMQ library [no]
   --enable-librav1e        enable AV1 encoding via rav1e [no]
   --enable-librsvg         enable SVG rasterization via librsvg [no]
   --enable-librubberband   enable rubberband needed for rubberband filter [no]
@@ -1789,6 +1790,7 @@ EXTERNAL_LIBRARY_LIST="
     libopenmpt
     libopus
     libpulse
+    librabbitmq
     librav1e
     librsvg
     librtmp
@@ -3434,6 +3436,8 @@ unix_protocol_deps="sys_un_h"
 unix_protocol_select="network"
 
 # external library protocols
+libamqp_protocol_deps="librabbitmq"
+libamqp_protocol_select="network"
 librtmp_protocol_deps="librtmp"
 librtmpe_protocol_deps="librtmp"
 librtmps_protocol_deps="librtmp"
@@ -6317,6 +6321,7 @@ enabled libopus           && {
     }
 }
 enabled libpulse          && require_pkg_config libpulse libpulse pulse/pulseaudio.h pa_context_new
+enabled librabbitmq       && require_pkg_config librabbitmq "librabbitmq >= 0.7.1" amqp.h amqp_new_connection
 enabled librav1e          && require_pkg_config librav1e "rav1e >= 0.1.0" rav1e.h rav1e_context_new
 enabled librsvg           && require_pkg_config librsvg librsvg-2.0 librsvg-2.0/librsvg/rsvg.h rsvg_handle_render_cairo
 enabled librtmp           && require_pkg_config librtmp librtmp librtmp/rtmp.h RTMP_Socket
diff --git a/doc/general.texi b/doc/general.texi
index 87eaad7791..3684847ac1 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -1331,6 +1331,7 @@ performance on systems without hardware floating point support).
 
 @multitable @columnfractions .4 .1
 @item Name         @tab Support
+@item AMQP         @tab X
 @item file         @tab X
 @item FTP          @tab X
 @item Gopher       @tab X
diff --git a/doc/protocols.texi b/doc/protocols.texi
index 54a287f488..27df4759b6 100644
--- a/doc/protocols.texi
+++ b/doc/protocols.texi
@@ -51,6 +51,66 @@ in microseconds.
 
 A description of the currently available protocols follows.
 
+@section amqp
+
+Advanced Message Queueing Protocol (AMQP) version 0-9-1 is a broker based
+publish-subscribe communication protocol.
+
+FFmpeg must be compiled with --enable-librabbitmq to support AMQP. A separate
+AMQP broker must also be run. An example open-source AMQP broker is RabbitMQ.
+
+After starting the broker, an FFmpeg client may stream data to the broker using
+the command:
+
+@example
+ffmpeg -re -i input -f mpegts amqp://[[user]:[password]@@]hostname[:port]
+@end example
+
+Where hostname and port (default is 5672) is the address of the broker. The
+client may also set a user/password for authentication. The default for both
+fields is "guest".
+
+Muliple subscribers may stream from the broker using the command:
+@example
+ffplay amqp://[[user]:[password]@@]hostname[:port]
+@end example
+
+In RabbitMQ all data published to the broker flows through a specific exchange,
+and each subscribing client has an assigned queue/buffer. When a packet arrives
+at an exchange, it may be copied to a client's queue depending on the exchange
+and routing_key fields.
+
+The following options are supported:
+
+@table @option
+
+@item exchange
+Sets the exchange to use on the broker. RabbitMQ has several predefined
+exchanges: "amq.direct" is the default exchange, where the publisher and
+subscriber must have a matching routing_key; "amq.fanout" is the same as a
+broadcast operation (i.e. the data is forwarded to all queues on the fanout
+exchange independent of the routing_key); and "amq.topic" is similar to
+"amq.direct", but allows for more complex pattern matching (refer to the RabbitMQ
+documentation).
+
+@item routing_key
+Sets the routing key. The default value is "amqp". The routing key is used on
+the "amq.direct" and "amq.topic" exchanges to decide whether packets are written
+to the queue of a subscriber.
+
+@item pkt_size
+Maximum size of each packet sent/received to the broker. Default is 131072.
+Minimum is 4096 and max is any large value (representable by an int). When
+receiving packets, this sets an internal buffer size in FFmpeg. It should be
+equal to or greater than the size of the published packets to the broker. Otherwise
+the received message may be truncated causing decoding errors.
+
+@item connection_timeout
+The timeout in seconds during the initial connection to the broker. The
+default value is rw_timeout, or 5 seconds if rw_timeout is not set.
+
+@end table
+
 @section async
 
 Asynchronous data filling wrapper for input stream.
diff --git a/libavformat/Makefile b/libavformat/Makefile
index fbb29505ff..f84becd30a 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -630,6 +630,7 @@ OBJS-$(CONFIG_UDPLITE_PROTOCOL)          += udp.o ip.o
 OBJS-$(CONFIG_UNIX_PROTOCOL)             += unix.o
 
 # external library protocols
+OBJS-$(CONFIG_LIBAMQP_PROTOCOL)          += libamqp.o
 OBJS-$(CONFIG_LIBRTMP_PROTOCOL)          += librtmp.o
 OBJS-$(CONFIG_LIBRTMPE_PROTOCOL)         += librtmp.o
 OBJS-$(CONFIG_LIBRTMPS_PROTOCOL)         += librtmp.o
diff --git a/libavformat/libamqp.c b/libavformat/libamqp.c
new file mode 100644
index 0000000000..aaf0e51152
--- /dev/null
+++ b/libavformat/libamqp.c
@@ -0,0 +1,298 @@
+/*
+ * Advanced Message Queuing Protocol (AMQP) 0-9-1
+ * Copyright (c) 2020 Andriy Gelman
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <amqp.h>
+#include <amqp_tcp_socket.h>
+#include <sys/time.h>
+#include "avformat.h"
+#include "libavutil/avstring.h"
+#include "libavutil/opt.h"
+#include "libavutil/time.h"
+#include "network.h"
+#include "url.h"
+#include "urldecode.h"
+
+typedef struct AMQPContext {
+    const AVClass *class;
+    amqp_connection_state_t conn;
+    amqp_socket_t *socket;
+    const char *exchange;
+    const char *routing_key;
+    int pkt_size;
+    int64_t connection_timeout;
+    int pkt_size_overflow;
+} AMQPContext;
+
+#define STR_LEN           1024
+#define DEFAULT_CHANNEL   1
+
+#define OFFSET(x) offsetof(AMQPContext, x)
+#define D AV_OPT_FLAG_DECODING_PARAM
+#define E AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    { "pkt_size", "Maximum send/read packet size", OFFSET(pkt_size), AV_OPT_TYPE_INT, { .i64 = 131072 }, 4096, INT_MAX, .flags = D | E },
+    { "exchange", "Exchange to send/read packets", OFFSET(exchange), AV_OPT_TYPE_STRING, { .str = "amq.direct" }, 0, 0, .flags = D | E },
+    { "routing_key", "Key to filter streams", OFFSET(routing_key), AV_OPT_TYPE_STRING, { .str = "amqp" }, 0, 0, .flags = D | E },
+    { "connection_timeout", "Initial connection timeout", OFFSET(connection_timeout), AV_OPT_TYPE_DURATION, { .i64 = -1 }, -1, INT64_MAX, .flags = D | E},
+    { NULL }
+};
+
+static int amqp_proto_open(URLContext *h, const char *uri, int flags)
+{
+    int ret, server_msg;
+    char hostname[STR_LEN], credentials[STR_LEN];
+    int port;
+    const char *user, *password = NULL;
+    const char *user_decoded, *password_decoded;
+    char *p;
+    amqp_rpc_reply_t broker_reply;
+    struct timeval tval = { 0 };
+
+    AMQPContext *s = h->priv_data;
+
+    h->is_streamed     = 1;
+    h->max_packet_size = s->pkt_size;
+
+    av_url_split(NULL, 0, credentials, sizeof(credentials),
+                 hostname, sizeof(hostname), &port, NULL, 0, uri);
+
+    if (port < 0)
+        port = 5672;
+
+    if (hostname[0] == '\0' || port <= 0 || port > 65535 ) {
+        av_log(h, AV_LOG_ERROR, "Invalid hostname/port\n");
+        return AVERROR(EINVAL);
+    }
+
+    p = strchr(credentials, ':');
+    if (p) {
+        *p = '\0';
+        password = p + 1;
+    }
+
+    if (!password || *password == '\0')
+        password = "guest";
+
+    password_decoded = ff_urldecode(password, 0);
+    if (!password_decoded)
+        return AVERROR(ENOMEM);
+
+    user = credentials;
+    if (*user == '\0')
+        user = "guest";
+
+    user_decoded = ff_urldecode(user, 0);
+    if (!user_decoded) {
+        av_freep(&password_decoded);
+        return AVERROR(ENOMEM);
+    }
+
+    s->conn = amqp_new_connection();
+    if (!s->conn) {
+        av_freep(&user_decoded);
+        av_freep(&password_decoded);
+        av_log(h, AV_LOG_ERROR, "Error creating connection\n");
+        return AVERROR_EXTERNAL;
+    }
+
+    s->socket = amqp_tcp_socket_new(s->conn);
+    if (!s->socket) {
+        av_log(h, AV_LOG_ERROR, "Error creating socket\n");
+        goto destroy_connection;
+    }
+
+    if (s->connection_timeout < 0)
+        s->connection_timeout = (h->rw_timeout > 0 ? h->rw_timeout : 5000000);
+
+    tval.tv_sec  = s->connection_timeout / 1000000;
+    tval.tv_usec = s->connection_timeout % 1000000;
+    ret = amqp_socket_open_noblock(s->socket, hostname, port, &tval);
+
+    if (ret) {
+        av_log(h, AV_LOG_ERROR, "Error connecting to server: %s\n",
+                                 amqp_error_string2(ret));
+        goto destroy_connection;
+    }
+
+    broker_reply = amqp_login(s->conn, "/", 0, s->pkt_size, 0,
+                              AMQP_SASL_METHOD_PLAIN, user_decoded, password_decoded);
+
+    if (broker_reply.reply_type != AMQP_RESPONSE_NORMAL) {
+        av_log(h, AV_LOG_ERROR, "Error login\n");
+        server_msg = AMQP_ACCESS_REFUSED;
+        goto close_connection;
+    }
+
+    amqp_channel_open(s->conn, DEFAULT_CHANNEL);
+    broker_reply = amqp_get_rpc_reply(s->conn);
+
+    if (broker_reply.reply_type != AMQP_RESPONSE_NORMAL) {
+        av_log(h, AV_LOG_ERROR, "Error set channel\n");
+        server_msg = AMQP_CHANNEL_ERROR;
+        goto close_connection;
+    }
+
+    if (h->flags & AVIO_FLAG_READ) {
+        amqp_bytes_t queuename;
+        char queuename_buff[STR_LEN];
+        amqp_queue_declare_ok_t *r;
+
+        r = amqp_queue_declare(s->conn, DEFAULT_CHANNEL, amqp_empty_bytes,
+                               0, 0, 0, 1, amqp_empty_table);
+        broker_reply = amqp_get_rpc_reply(s->conn);
+        if (!r || broker_reply.reply_type != AMQP_RESPONSE_NORMAL) {
+            av_log(h, AV_LOG_ERROR, "Error declare queue\n");
+            server_msg = AMQP_RESOURCE_ERROR;
+            goto close_channel;
+        }
+
+        /* store queuename */
+        queuename.bytes = queuename_buff;
+        queuename.len = FFMIN(r->queue.len, STR_LEN);
+        memcpy(queuename.bytes, r->queue.bytes, queuename.len);
+
+        amqp_queue_bind(s->conn, DEFAULT_CHANNEL, queuename,
+                        amqp_cstring_bytes(s->exchange),
+                        amqp_cstring_bytes(s->routing_key), amqp_empty_table);
+
+        broker_reply = amqp_get_rpc_reply(s->conn);
+        if (broker_reply.reply_type != AMQP_RESPONSE_NORMAL) {
+            av_log(h, AV_LOG_ERROR, "Queue bind error\n");
+            server_msg = AMQP_INTERNAL_ERROR;
+            goto close_channel;
+        }
+
+        amqp_basic_consume(s->conn, DEFAULT_CHANNEL, queuename, amqp_empty_bytes,
+                           0, 1, 0, amqp_empty_table);
+
+        broker_reply = amqp_get_rpc_reply(s->conn);
+        if (broker_reply.reply_type != AMQP_RESPONSE_NORMAL) {
+            av_log(h, AV_LOG_ERROR, "Set consume error\n");
+            server_msg = AMQP_INTERNAL_ERROR;
+            goto close_channel;
+        }
+    }
+
+    av_freep(&user_decoded);
+    av_freep(&password_decoded);
+    return 0;
+
+close_channel:
+    amqp_channel_close(s->conn, DEFAULT_CHANNEL, server_msg);
+close_connection:
+    amqp_connection_close(s->conn, server_msg);
+destroy_connection:
+    amqp_destroy_connection(s->conn);
+
+    av_freep(&user_decoded);
+    av_freep(&password_decoded);
+    return AVERROR_EXTERNAL;
+}
+
+static int amqp_proto_write(URLContext *h, const unsigned char *buf, int size)
+{
+    int ret;
+    AMQPContext *s = h->priv_data;
+    int fd = amqp_socket_get_sockfd(s->socket);
+
+    amqp_bytes_t message = { size, (void *)buf };
+    amqp_basic_properties_t props;
+
+    ret = ff_network_wait_fd_timeout(fd, 1, h->rw_timeout, &h->interrupt_callback);
+    if (ret)
+        return ret;
+
+    props._flags = AMQP_BASIC_CONTENT_TYPE_FLAG | AMQP_BASIC_DELIVERY_MODE_FLAG;
+    props.content_type = amqp_cstring_bytes("octet/stream");
+    props.delivery_mode = 2; /* persistent delivery mode */
+
+    ret = amqp_basic_publish(s->conn, DEFAULT_CHANNEL, amqp_cstring_bytes(s->exchange),
+                             amqp_cstring_bytes(s->routing_key), 0, 0,
+                             &props, message);
+
+    if (ret) {
+        av_log(h, AV_LOG_ERROR, "Error publish: %s\n", amqp_error_string2(ret));
+        return AVERROR_EXTERNAL;
+    }
+
+    return size;
+}
+
+static int amqp_proto_read(URLContext *h, unsigned char *buf, int size)
+{
+    AMQPContext *s = h->priv_data;
+    int fd = amqp_socket_get_sockfd(s->socket);
+    int ret;
+
+    amqp_rpc_reply_t broker_reply;
+    amqp_envelope_t envelope;
+
+    ret = ff_network_wait_fd_timeout(fd, 0, h->rw_timeout, &h->interrupt_callback);
+    if (ret)
+        return ret;
+
+    amqp_maybe_release_buffers(s->conn);
+    broker_reply = amqp_consume_message(s->conn, &envelope, NULL, 0);
+
+    if (broker_reply.reply_type != AMQP_RESPONSE_NORMAL)
+        return AVERROR_EXTERNAL;
+
+    if (envelope.message.body.len > size) {
+        s->pkt_size_overflow = FFMAX(s->pkt_size_overflow, envelope.message.body.len);
+        av_log(h, AV_LOG_WARNING, "Message exceeds space in the buffer. "
+                                  "Message will be truncated. Setting -pkt_size %d "
+                                  "may resolve this issue.\n", s->pkt_size_overflow);
+    }
+    size = FFMIN(size, envelope.message.body.len);
+
+    memcpy(buf, envelope.message.body.bytes, size);
+    amqp_destroy_envelope(&envelope);
+
+    return size;
+}
+
+static int amqp_proto_close(URLContext *h)
+{
+    AMQPContext *s = h->priv_data;
+    amqp_channel_close(s->conn, DEFAULT_CHANNEL, AMQP_REPLY_SUCCESS);
+    amqp_connection_close(s->conn, AMQP_REPLY_SUCCESS);
+    amqp_destroy_connection(s->conn);
+
+    return 0;
+}
+
+static const AVClass amqp_context_class = {
+    .class_name = "amqp",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+const URLProtocol ff_libamqp_protocol = {
+    .name            = "amqp",
+    .url_close       = amqp_proto_close,
+    .url_open        = amqp_proto_open,
+    .url_read        = amqp_proto_read,
+    .url_write       = amqp_proto_write,
+    .priv_data_size  = sizeof(AMQPContext),
+    .priv_data_class = &amqp_context_class,
+    .flags           = URL_PROTOCOL_FLAG_NETWORK,
+};
diff --git a/libavformat/protocols.c b/libavformat/protocols.c
index 29fb99e7fa..f1b8eab0fd 100644
--- a/libavformat/protocols.c
+++ b/libavformat/protocols.c
@@ -60,6 +60,7 @@ extern const URLProtocol ff_tls_protocol;
 extern const URLProtocol ff_udp_protocol;
 extern const URLProtocol ff_udplite_protocol;
 extern const URLProtocol ff_unix_protocol;
+extern const URLProtocol ff_libamqp_protocol;
 extern const URLProtocol ff_librtmp_protocol;
 extern const URLProtocol ff_librtmpe_protocol;
 extern const URLProtocol ff_librtmps_protocol;
diff --git a/libavformat/version.h b/libavformat/version.h
index a233b67351..e815c1f3c4 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,7 +32,7 @@
 // Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
 // Also please add any ticket numbers that you believe might be affected here
 #define LIBAVFORMAT_VERSION_MAJOR  58
-#define LIBAVFORMAT_VERSION_MINOR  40
+#define LIBAVFORMAT_VERSION_MINOR  41
 #define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \