Squashed 'third_party/rawrtc/rawrtc-common/' content from commit aff7a3a3b

Change-Id: I2cb019410e8d0e1e0bf814577b0ef83aeb32c7fd
git-subtree-dir: third_party/rawrtc/rawrtc-common
git-subtree-split: aff7a3a3b9bbf49f7d2fc8b123edd301825b3e1c
diff --git a/src/message_buffer/buffer.c b/src/message_buffer/buffer.c
new file mode 100644
index 0000000..75004f1
--- /dev/null
+++ b/src/message_buffer/buffer.c
@@ -0,0 +1,99 @@
+#include <rawrtcc/code.h>
+#include <rawrtcc/message_buffer.h>
+#include <re.h>
+
+/*
+ * Message buffer.
+ */
+struct buffered_message {
+    struct le le;
+    struct mbuf* buffer;  // referenced
+    void* context;  // referenced, nullable
+};
+
+/*
+ * Destructor for an existing buffered message.
+ */
+static void rawrtc_message_buffer_destroy(void* arg) {
+    struct buffered_message* const buffered_message = arg;
+
+    // Un-reference
+    mem_deref(buffered_message->context);
+    mem_deref(buffered_message->buffer);
+}
+
+/*
+ * Create a message buffer and add it to a list.
+ *
+ * TODO: Add timestamp to be able to ignore old messages
+ */
+enum rawrtc_code rawrtc_message_buffer_append(
+    struct list* const message_buffer,
+    struct mbuf* const buffer,  // referenced
+    void* const context  // referenced, nullable
+) {
+    struct buffered_message* buffered_message;
+
+    // Check arguments
+    if (!message_buffer || !buffer) {
+        return RAWRTC_CODE_INVALID_ARGUMENT;
+    }
+
+    // Create buffered message
+    buffered_message = mem_zalloc(sizeof(*buffered_message), rawrtc_message_buffer_destroy);
+    if (!buffered_message) {
+        return RAWRTC_CODE_NO_MEMORY;
+    }
+
+    // Set fields
+    buffered_message->buffer = mem_ref(buffer);
+    buffered_message->context = mem_ref(context);
+
+    // Add to list
+    list_append(message_buffer, &buffered_message->le, buffered_message);
+    return RAWRTC_CODE_SUCCESS;
+}
+
+/*
+ * Apply a receive handler to buffered messages.
+ *
+ * Will stop iterating and return `RAWRTC_CODE_STOP_ITERATION` in case
+ * the message handler returned `false`.
+ */
+enum rawrtc_code rawrtc_message_buffer_clear(
+    struct list* const message_buffer,
+    rawrtc_message_buffer_handler* const message_handler,
+    void* arg) {
+    struct le* le;
+    bool unlink;
+
+    // Check arguments
+    if (!message_buffer || !message_handler) {
+        return RAWRTC_CODE_INVALID_ARGUMENT;
+    }
+
+    // Handle each message
+    le = list_head(message_buffer);
+    while (le != NULL) {
+        struct buffered_message* const buffered_message = le->data;
+
+        // Handle message
+        unlink = message_handler(buffered_message->buffer, buffered_message->context, arg);
+        if (unlink) {
+            list_unlink(le);
+        }
+
+        // Get next message
+        le = le->next;
+
+        // Remove message
+        if (unlink) {
+            mem_deref(buffered_message);
+        } else {
+            return RAWRTC_CODE_STOP_ITERATION;
+        }
+    }
+
+    // Done
+    return RAWRTC_CODE_SUCCESS;
+}