Add type to returned response.

Makes `ipc_recv_response` return a struct with size, type and payload
rather than just the payload string.

This is useful if the type has to be checked on the client.

3 files changed, 39 insertions, 13 deletions

diff --git a/common/ipc-client.c b/common/ipc-client.c
index e92a09fe..81348913 100644
--- a/common/ipc-client.c
+++ b/common/ipc-client.c
@@ -10,6 +10,7 @@
 #include "stringop.h"
 #include "ipc.h"
 #include "readline.h"
+#include "ipc-client.h"
 
 static const char ipc_magic[] = {'i', '3', '-', 'i', 'p', 'c'};
 static const size_t ipc_header_size = sizeof(ipc_magic)+8;
@@ -39,7 +40,7 @@ int ipc_open_socket(const char *socket_path) {
         return socketfd;
 }
 
-char *ipc_recv_response(int socketfd, uint32_t *len) {
+struct ipc_response *ipc_recv_response(int socketfd) {
         char data[ipc_header_size];
         uint32_t *data32 = (uint32_t *)(data + sizeof(ipc_magic));
 
@@ -52,21 +53,29 @@ char *ipc_recv_response(int socketfd, uint32_t *len) {
                 total += received;
         }
 
+        struct ipc_response *response = malloc(sizeof(struct ipc_response));
         total = 0;
-        *len = data32[0];
-        char *response = malloc(*len + 1);
-        while (total < *len) {
-                ssize_t received = recv(socketfd, response + total, *len - total, 0);
+        response->size = data32[0];
+        response->type = data32[1];
+        char *payload = malloc(response->size + 1);
+        while (total < response->size) {
+                ssize_t received = recv(socketfd, payload + total, response->size - total, 0);
                 if (received < 0) {
                         sway_abort("Unable to receive IPC response");
                 }
                 total += received;
         }
-        response[*len] = '\0';
+        payload[response->size] = '\0';
+        response->payload = payload;
 
         return response;
 }
 
+void free_ipc_response(struct ipc_response *response) {
+        free(response->payload);
+        free(response);
+}
+
 char *ipc_single_command(int socketfd, uint32_t type, const char *payload, uint32_t *len) {
         char data[ipc_header_size];
         uint32_t *data32 = (uint32_t *)(data + sizeof(ipc_magic));
@@ -82,5 +91,10 @@ char *ipc_single_command(int socketfd, uint32_t type, const char *payload, uint3
                 sway_abort("Unable to send IPC payload");
         }
 
-        return ipc_recv_response(socketfd, len);
+        struct ipc_response *resp = ipc_recv_response(socketfd);
+        char *response = resp->payload;
+        *len = resp->size;
+        free(resp);
+
+        return response;
 }
diff --git a/include/ipc-client.h b/include/ipc-client.h
index a4cfd87f..030c80b6 100644
--- a/include/ipc-client.h
+++ b/include/ipc-client.h
@@ -4,6 +4,16 @@
 #include "ipc.h"
 
 /**
+ * IPC response including type of IPC response, size of payload and the json
+ * encoded payload string.
+ */
+struct ipc_response {
+        uint32_t size;
+        uint32_t type;
+        char *payload;
+};
+
+/**
  * Gets the path to the IPC socket from sway.
  */
 char *get_socketpath(void);
@@ -17,9 +27,12 @@ int ipc_open_socket(const char *socket_path);
  */
 char *ipc_single_command(int socketfd, uint32_t type, const char *payload, uint32_t *len);
 /**
- * Receives a single IPC resposne and returns the buffer. len will be updated
- * with the length of the buffer returned from sway.
+ * Receives a single IPC response and returns an ipc_response.
+ */
+struct ipc_response *ipc_recv_response(int socketfd);
+/**
+ * Free ipc_response struct
  */
-char *ipc_recv_response(int socketfd, uint32_t *len);
+void free_ipc_response(struct ipc_response *response);
 
 #endif
diff --git a/swaybar/main.c b/swaybar/main.c
index aa761b7d..d534345a 100644
--- a/swaybar/main.c
+++ b/swaybar/main.c
@@ -1025,9 +1025,8 @@ void poll_for_update() {
 
                 if (FD_ISSET(ipc_event_socketfd, &readfds)) {
                         sway_log(L_DEBUG, "Got workspace update.");
-                        uint32_t len;
-                        char *buf = ipc_recv_response(ipc_event_socketfd, &len);
-                        free(buf);
+                        struct ipc_response *resp = ipc_recv_response(ipc_event_socketfd);
+                        free_ipc_response(resp);
                         ipc_update_workspaces();
                         dirty = true;
                 }