Remove amqp_rpc_reply global variable, making it instead state-local

and accessible only through amqp_get_rpc_reply(). Add a better comment
on amqp_get_rpc_reply() to be a little clearer about when it's
inappropriate to use it.

11 files changed, 48 insertions, 42 deletions

diff --git a/examples/amqp_bind.c b/examples/amqp_bind.c
index afbfed9..fa3f907 100644
--- a/examples/amqp_bind.c
+++ b/examples/amqp_bind.c
@@ -38,14 +38,14 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   amqp_queue_bind(conn, 1,
 		  amqp_cstring_bytes(queue),
 		  amqp_cstring_bytes(exchange),
 		  amqp_cstring_bytes(bindingkey),
 		  AMQP_EMPTY_TABLE);
-  die_on_amqp_error(amqp_rpc_reply, "Unbinding");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Unbinding");
 
   die_on_amqp_error(amqp_channel_close(conn, 1, AMQP_REPLY_SUCCESS), "Closing channel");
   die_on_amqp_error(amqp_connection_close(conn, AMQP_REPLY_SUCCESS), "Closing connection");
diff --git a/examples/amqp_consumer.c b/examples/amqp_consumer.c
index 230a94e..f93ddf3 100644
--- a/examples/amqp_consumer.c
+++ b/examples/amqp_consumer.c
@@ -107,12 +107,12 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   {
     amqp_queue_declare_ok_t *r = amqp_queue_declare(conn, 1, AMQP_EMPTY_BYTES, 0, 0, 0, 1,
 						    AMQP_EMPTY_TABLE);
-    die_on_amqp_error(amqp_rpc_reply, "Declaring queue");
+    die_on_amqp_error(amqp_get_rpc_reply(conn), "Declaring queue");
     queuename = amqp_bytes_malloc_dup(r->queue);
     if (queuename.bytes == NULL) {
       die_on_error(-ENOMEM, "Copying queue name");
@@ -121,10 +121,10 @@ int main(int argc, char const * const *argv) {
 
   amqp_queue_bind(conn, 1, queuename, amqp_cstring_bytes(exchange), amqp_cstring_bytes(bindingkey),
 		  AMQP_EMPTY_TABLE);
-  die_on_amqp_error(amqp_rpc_reply, "Binding queue");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Binding queue");
 
   amqp_basic_consume(conn, 1, queuename, AMQP_EMPTY_BYTES, 0, 1, 0);
-  die_on_amqp_error(amqp_rpc_reply, "Consuming");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Consuming");
 
   run(conn);
 
diff --git a/examples/amqp_exchange_declare.c b/examples/amqp_exchange_declare.c
index 02884e8..d0d456c 100644
--- a/examples/amqp_exchange_declare.c
+++ b/examples/amqp_exchange_declare.c
@@ -36,11 +36,11 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   amqp_exchange_declare(conn, 1, amqp_cstring_bytes(exchange), amqp_cstring_bytes(exchangetype),
 			0, 0, 0, AMQP_EMPTY_TABLE);
-  die_on_amqp_error(amqp_rpc_reply, "Declaring exchange");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Declaring exchange");
 
   die_on_amqp_error(amqp_channel_close(conn, 1, AMQP_REPLY_SUCCESS), "Closing channel");
   die_on_amqp_error(amqp_connection_close(conn, AMQP_REPLY_SUCCESS), "Closing connection");
diff --git a/examples/amqp_listen.c b/examples/amqp_listen.c
index d39e4b4..e487255 100644
--- a/examples/amqp_listen.c
+++ b/examples/amqp_listen.c
@@ -43,12 +43,12 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   {
     amqp_queue_declare_ok_t *r = amqp_queue_declare(conn, 1, AMQP_EMPTY_BYTES, 0, 0, 0, 1,
 						    AMQP_EMPTY_TABLE);
-    die_on_amqp_error(amqp_rpc_reply, "Declaring queue");
+    die_on_amqp_error(amqp_get_rpc_reply(conn), "Declaring queue");
     queuename = amqp_bytes_malloc_dup(r->queue);
     if (queuename.bytes == NULL) {
       die_on_error(-ENOMEM, "Copying queue name");
@@ -57,10 +57,10 @@ int main(int argc, char const * const *argv) {
 
   amqp_queue_bind(conn, 1, queuename, amqp_cstring_bytes(exchange), amqp_cstring_bytes(bindingkey),
 		  AMQP_EMPTY_TABLE);
-  die_on_amqp_error(amqp_rpc_reply, "Binding queue");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Binding queue");
 
   amqp_basic_consume(conn, 1, queuename, AMQP_EMPTY_BYTES, 0, 1, 0);
-  die_on_amqp_error(amqp_rpc_reply, "Consuming");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Consuming");
 
   {
     amqp_frame_t frame;
diff --git a/examples/amqp_listenq.c b/examples/amqp_listenq.c
index b6d37fc..2478127 100644
--- a/examples/amqp_listenq.c
+++ b/examples/amqp_listenq.c
@@ -39,10 +39,10 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   amqp_basic_consume(conn, 1, amqp_cstring_bytes(queuename), AMQP_EMPTY_BYTES, 0, 0, 0);
-  die_on_amqp_error(amqp_rpc_reply, "Consuming");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Consuming");
 
   {
     amqp_frame_t frame;
diff --git a/examples/amqp_producer.c b/examples/amqp_producer.c
index a60cb3e..e0b8079 100644
--- a/examples/amqp_producer.c
+++ b/examples/amqp_producer.c
@@ -95,7 +95,7 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   send_batch(conn, "test queue", rate_limit, message_count);
 
diff --git a/examples/amqp_sendstring.c b/examples/amqp_sendstring.c
index a321f52..e512ef0 100644
--- a/examples/amqp_sendstring.c
+++ b/examples/amqp_sendstring.c
@@ -38,7 +38,7 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   {
     amqp_basic_properties_t props;
diff --git a/examples/amqp_unbind.c b/examples/amqp_unbind.c
index 9a9a35c..e033702 100644
--- a/examples/amqp_unbind.c
+++ b/examples/amqp_unbind.c
@@ -38,14 +38,14 @@ int main(int argc, char const * const *argv) {
   die_on_amqp_error(amqp_login(conn, "/", 0, 131072, 0, AMQP_SASL_METHOD_PLAIN, "guest", "guest"),
 		    "Logging in");
   amqp_channel_open(conn, 1);
-  die_on_amqp_error(amqp_rpc_reply, "Opening channel");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Opening channel");
 
   amqp_queue_unbind(conn, 1,
 		    amqp_cstring_bytes(queue),
 		    amqp_cstring_bytes(exchange),
 		    amqp_cstring_bytes(bindingkey),
 		    AMQP_EMPTY_TABLE);
-  die_on_amqp_error(amqp_rpc_reply, "Unbinding");
+  die_on_amqp_error(amqp_get_rpc_reply(conn), "Unbinding");
 
   die_on_amqp_error(amqp_channel_close(conn, 1, AMQP_REPLY_SUCCESS), "Closing channel");
   die_on_amqp_error(amqp_connection_close(conn, AMQP_REPLY_SUCCESS), "Closing connection");
diff --git a/librabbitmq/amqp.h b/librabbitmq/amqp.h
index a2b062c..906c900 100644
--- a/librabbitmq/amqp.h
+++ b/librabbitmq/amqp.h
@@ -337,8 +337,6 @@ extern amqp_rpc_reply_t amqp_login(amqp_connection_state_t state,
 				   int heartbeat,
 				   amqp_sasl_method_enum sasl_method, ...);
 
-extern amqp_rpc_reply_t amqp_rpc_reply;
-
 extern struct amqp_channel_open_ok_t_ *amqp_channel_open(amqp_connection_state_t state,
 							 amqp_channel_t channel);
 
@@ -423,9 +421,19 @@ extern struct amqp_queue_purge_ok_t_ *amqp_queue_purge(amqp_connection_state_t s
 extern amqp_boolean_t amqp_data_in_buffer(amqp_connection_state_t state);
 
 /*
- * Expose amqp_rpc_reply to libraries.
+ * For those API operations (such as amqp_basic_ack,
+ * amqp_queue_declare, and so on) that do not themselves return
+ * amqp_rpc_reply_t instances, we need some way of discovering what,
+ * if anything, went wrong. amqp_get_rpc_reply() returns the most
+ * recent amqp_rpc_reply_t instance corresponding to such an API
+ * operation for the given connection.
+ *
+ * Only use it for operations that do not themselves return
+ * amqp_rpc_reply_t; operations that do return amqp_rpc_reply_t
+ * generally do NOT update this per-connection-global amqp_rpc_reply_t
+ * instance.
  */
-extern amqp_rpc_reply_t amqp_get_rpc_reply(void);
+extern amqp_rpc_reply_t amqp_get_rpc_reply(amqp_connection_state_t state);
 
 #ifdef __cplusplus
 }
diff --git a/librabbitmq/amqp_api.c b/librabbitmq/amqp_api.c
index 1d329e0..7cb865d 100644
--- a/librabbitmq/amqp_api.c
+++ b/librabbitmq/amqp_api.c
@@ -10,17 +10,15 @@
 
 #include <assert.h>
 
-amqp_rpc_reply_t amqp_rpc_reply;
-
-#define RPC_REPLY(replytype)					\
-  (amqp_rpc_reply.reply_type == AMQP_RESPONSE_NORMAL		\
-   ? (replytype *) amqp_rpc_reply.reply.decoded	\
+#define RPC_REPLY(replytype)						\
+  (state->most_recent_api_result.reply_type == AMQP_RESPONSE_NORMAL	\
+   ? (replytype *) state->most_recent_api_result.reply.decoded		\
    : NULL)
 
 amqp_channel_open_ok_t *amqp_channel_open(amqp_connection_state_t state,
 					  amqp_channel_t channel)
 {
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_SIMPLE_RPC(state, channel, CHANNEL, OPEN, OPEN_OK,
 		    amqp_channel_open_t,
 		    AMQP_EMPTY_BYTES);
@@ -118,7 +116,7 @@ amqp_exchange_declare_ok_t *amqp_exchange_declare(amqp_connection_state_t state,
 						  amqp_boolean_t auto_delete,
 						  amqp_table_t arguments)
 {
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_SIMPLE_RPC(state, channel, EXCHANGE, DECLARE, DECLARE_OK,
 		    amqp_exchange_declare_t,
 		    0, exchange, type, passive, durable, auto_delete, 0, 0, arguments);
@@ -134,7 +132,7 @@ amqp_queue_declare_ok_t *amqp_queue_declare(amqp_connection_state_t state,
 					    amqp_boolean_t auto_delete,
 					    amqp_table_t arguments)
 {
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_SIMPLE_RPC(state, channel, QUEUE, DECLARE, DECLARE_OK,
 		    amqp_queue_declare_t,
 		    0, queue, passive, durable, exclusive, auto_delete, 0, arguments);
@@ -148,7 +146,7 @@ amqp_queue_bind_ok_t *amqp_queue_bind(amqp_connection_state_t state,
 				      amqp_bytes_t routing_key,
 				      amqp_table_t arguments)
 {
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_SIMPLE_RPC(state, channel, QUEUE, BIND, BIND_OK,
 		    amqp_queue_bind_t,
 		    0, queue, exchange, routing_key, 0, arguments);
@@ -162,7 +160,7 @@ amqp_queue_unbind_ok_t *amqp_queue_unbind(amqp_connection_state_t state,
 					  amqp_bytes_t binding_key,
 					  amqp_table_t arguments)
 {
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_SIMPLE_RPC(state, channel, QUEUE, UNBIND, UNBIND_OK,
 		    amqp_queue_unbind_t,
 		    0, queue, exchange, binding_key, arguments);
@@ -177,7 +175,7 @@ amqp_basic_consume_ok_t *amqp_basic_consume(amqp_connection_state_t state,
 					    amqp_boolean_t no_ack,
 					    amqp_boolean_t exclusive)
 {
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_SIMPLE_RPC(state, channel, BASIC, CONSUME, CONSUME_OK,
 		    amqp_basic_consume_t,
 		    0, queue, consumer_tag, no_local, no_ack, exclusive, 0);
@@ -203,8 +201,9 @@ amqp_queue_purge_ok_t *amqp_queue_purge(amqp_connection_state_t state,
 					amqp_bytes_t queue,
 					amqp_boolean_t no_wait)
 {
-  amqp_rpc_reply = AMQP_SIMPLE_RPC(state, channel, QUEUE, PURGE, PURGE_OK,
-				   amqp_queue_purge_t, channel, queue, no_wait);
+  state->most_recent_api_result =
+    AMQP_SIMPLE_RPC(state, channel, QUEUE, PURGE, PURGE_OK,
+		    amqp_queue_purge_t, channel, queue, no_wait);
   return RPC_REPLY(amqp_queue_purge_ok_t);
 }
 
@@ -216,17 +215,14 @@ amqp_rpc_reply_t amqp_basic_get(amqp_connection_state_t state,
   amqp_method_number_t replies[] = { AMQP_BASIC_GET_OK_METHOD,
 				     AMQP_BASIC_GET_EMPTY_METHOD,
 				     0 };
-  amqp_rpc_reply =
+  state->most_recent_api_result =
     AMQP_MULTIPLE_RESPONSE_RPC(state, channel, BASIC, GET, replies,
 			       amqp_basic_get_t,
 			       channel, queue, no_ack);
-  return amqp_rpc_reply;
+  return state->most_recent_api_result;
 }
 
-/*
- * Expose amqp_rpc_reply to dynamically linked libraries
- */
-amqp_rpc_reply_t amqp_get_rpc_reply(void)
+amqp_rpc_reply_t amqp_get_rpc_reply(amqp_connection_state_t state)
 {
-	return amqp_rpc_reply;
+  return state->most_recent_api_result;
 }
diff --git a/librabbitmq/amqp_private.h b/librabbitmq/amqp_private.h
index 03a46fe..aba63b5 100644
--- a/librabbitmq/amqp_private.h
+++ b/librabbitmq/amqp_private.h
@@ -71,6 +71,8 @@ struct amqp_connection_state_t_ {
 
   amqp_link_t *first_queued_frame;
   amqp_link_t *last_queued_frame;
+
+  amqp_rpc_reply_t most_recent_api_result;
 };
 
 #define CHECK_LIMIT(b, o, l, v) ({ if ((o + l) > (b).len) { return -EFAULT; } (v); })