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// Copyright 2007 - 2021, Alan Antonuk and the rabbitmq-c contributors.
// SPDX-License-Identifier: mit
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"
#include "process.h"
#define MAX_LISTEN_KEYS 1024
#define LISTEN_KEYS_DELIMITER ","
/* Convert a amqp_bytes_t to an escaped string form for printing. We
use the same escaping conventions as rabbitmqctl. */
static char *stringify_bytes(amqp_bytes_t bytes) {
/* We will need up to 4 chars per byte, plus the terminating 0 */
char *res = malloc(bytes.len * 4 + 1);
uint8_t *data = bytes.bytes;
char *p = res;
size_t i;
for (i = 0; i < bytes.len; i++) {
if (data[i] >= 32 && data[i] != 127) {
*p++ = data[i];
} else {
*p++ = '\\';
*p++ = '0' + (data[i] >> 6);
*p++ = '0' + (data[i] >> 3 & 0x7);
*p++ = '0' + (data[i] & 0x7);
}
}
*p = 0;
return res;
}
static amqp_bytes_t setup_queue(amqp_connection_state_t conn, char *queue,
char *exchange, char *routing_key, int declare,
int exclusive) {
amqp_bytes_t queue_bytes = cstring_bytes(queue);
char *routing_key_rest;
char *routing_key_token;
char *routing_tmp;
int routing_key_count = 0;
/* if an exchange name wasn't provided, check that we don't have options that
* require it. */
if (!exchange && routing_key) {
fprintf(stderr,
"--routing-key option requires an exchange name to be provided "
"with --exchange\n");
exit(1);
}
if (!queue || exchange || declare || exclusive) {
/* Declare the queue as auto-delete. */
amqp_queue_declare_ok_t *res = amqp_queue_declare(
conn, 1, queue_bytes, 0, 0, exclusive, 1, amqp_empty_table);
if (!res) {
die_rpc(amqp_get_rpc_reply(conn), "queue.declare");
}
if (!queue) {
/* the server should have provided a queue name */
char *sq;
queue_bytes = amqp_bytes_malloc_dup(res->queue);
sq = stringify_bytes(queue_bytes);
fprintf(stderr, "Server provided queue name: %s\n", sq);
free(sq);
}
/* Bind to an exchange if requested */
if (exchange) {
amqp_bytes_t eb = amqp_cstring_bytes(exchange);
routing_tmp = strdup(routing_key);
if (NULL == routing_tmp) {
fprintf(stderr, "could not allocate memory to parse routing key\n");
exit(1);
}
for (routing_key_token =
strtok_r(routing_tmp, LISTEN_KEYS_DELIMITER, &routing_key_rest);
NULL != routing_key_token && routing_key_count < MAX_LISTEN_KEYS - 1;
routing_key_token =
strtok_r(NULL, LISTEN_KEYS_DELIMITER, &routing_key_rest)) {
if (!amqp_queue_bind(conn, 1, queue_bytes, eb,
cstring_bytes(routing_key_token),
amqp_empty_table)) {
die_rpc(amqp_get_rpc_reply(conn), "queue.bind");
}
}
free(routing_tmp);
}
}
return queue_bytes;
}
#define AMQP_CONSUME_MAX_PREFETCH_COUNT 65535
static void do_consume(amqp_connection_state_t conn, amqp_bytes_t queue,
int no_ack, int count, int prefetch_count,
const char *const *argv) {
int i;
/* If there is a limit, set the qos to match */
if (count > 0 && count <= AMQP_CONSUME_MAX_PREFETCH_COUNT &&
!amqp_basic_qos(conn, 1, 0, count, 0)) {
die_rpc(amqp_get_rpc_reply(conn), "basic.qos");
}
/* if there is a maximum number of messages to be received at a time, set the
* qos to match */
if (prefetch_count > 0 && prefetch_count <= AMQP_CONSUME_MAX_PREFETCH_COUNT) {
/* the maximum number of messages to be received at a time must be less
* than the global maximum number of messages. */
if (!(count > 0 && count <= AMQP_CONSUME_MAX_PREFETCH_COUNT &&
prefetch_count >= count)) {
if (!amqp_basic_qos(conn, 1, 0, prefetch_count, 0)) {
die_rpc(amqp_get_rpc_reply(conn), "basic.qos");
}
}
}
if (!amqp_basic_consume(conn, 1, queue, amqp_empty_bytes, 0, no_ack, 0,
amqp_empty_table)) {
die_rpc(amqp_get_rpc_reply(conn), "basic.consume");
}
for (i = 0; count < 0 || i < count; i++) {
amqp_frame_t frame;
struct pipeline pl;
uint64_t delivery_tag;
amqp_basic_deliver_t *deliver;
int res = amqp_simple_wait_frame(conn, &frame);
die_amqp_error(res, "waiting for header frame");
if (frame.frame_type != AMQP_FRAME_METHOD ||
frame.payload.method.id != AMQP_BASIC_DELIVER_METHOD) {
continue;
}
deliver = (amqp_basic_deliver_t *)frame.payload.method.decoded;
delivery_tag = deliver->delivery_tag;
pipeline(argv, &pl);
copy_body(conn, pl.infd);
if (finish_pipeline(&pl) && !no_ack)
die_amqp_error(amqp_basic_ack(conn, 1, delivery_tag, 0), "basic.ack");
amqp_maybe_release_buffers(conn);
}
}
int main(int argc, const char **argv) {
poptContext opts;
amqp_connection_state_t conn;
const char *const *cmd_argv;
static char *queue = NULL;
static char *exchange = NULL;
static char *routing_key = NULL;
static int declare = 0;
static int exclusive = 0;
static int no_ack = 0;
static int count = -1;
static int prefetch_count = -1;
amqp_bytes_t queue_bytes;
struct poptOption options[] = {
INCLUDE_OPTIONS(connect_options),
{"queue", 'q', POPT_ARG_STRING, &queue, 0, "the queue to consume from",
"queue"},
{"exchange", 'e', POPT_ARG_STRING, &exchange, 0,
"bind the queue to this exchange", "exchange"},
{"routing-key", 'r', POPT_ARG_STRING, &routing_key, 0,
"the routing key to bind with", "routing key"},
{"declare", 'd', POPT_ARG_NONE, &declare, 0,
"declare an exclusive queue (deprecated, use --exclusive instead)",
NULL},
{"exclusive", 'x', POPT_ARG_NONE, &exclusive, 0,
"declare the queue as exclusive", NULL},
{"no-ack", 'A', POPT_ARG_NONE, &no_ack, 0, "consume in no-ack mode",
NULL},
{"count", 'c', POPT_ARG_INT, &count, 0,
"stop consuming after this many messages are consumed", "limit"},
{"prefetch-count", 'p', POPT_ARG_INT, &prefetch_count, 0,
"receive only this many message at a time from the server", "limit"},
POPT_AUTOHELP{NULL, '\0', 0, NULL, 0, NULL, NULL}};
opts = process_options(argc, argv, options, "[OPTIONS]... <command> <args>");
cmd_argv = poptGetArgs(opts);
if (!cmd_argv || !cmd_argv[0]) {
fprintf(stderr, "consuming command not specified\n");
poptPrintUsage(opts, stderr, 0);
goto error;
}
conn = make_connection();
queue_bytes =
setup_queue(conn, queue, exchange, routing_key, declare, exclusive);
do_consume(conn, queue_bytes, no_ack, count, prefetch_count, cmd_argv);
close_connection(conn);
return 0;
error:
poptFreeContext(opts);
return 1;
}
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