1 files changed, 31 insertions, 12 deletions

diff --git a/proto/puzbusv1.c b/proto/puzbusv1.c
index 3ff7c63..d6cd597 100644
--- a/proto/puzbusv1.c
+++ b/proto/puzbusv1.c
@@ -1,25 +1,44 @@
 #include <mpack.h>
 #include <stdio.h>
 
+// MIN() macro
+#include <sys/param.h>
+// TODO: check if this works on pico as well
+
 #include "puzbusv1.h"
 
-int pb_read(struct pb_msg* target, char* buf, size_t buf_sz) {
-	mpack_reader_t reader;
-	printf("read %lu bytes...\n", buf_sz);
+bool pb_read(struct pb_msg* target, char* buf, size_t buf_sz) {
+	// remaining bytes to be read to target->data; this is the only variable that
+	// needs to persist between buffer blocks, and is therefore static
+	static size_t rdata = 0;
 
+	// a new reader is used per buffer block passed to this function
+	mpack_reader_t reader;
 	mpack_reader_init_data(&reader, buf, buf_sz);
 
-	uint16_t address = mpack_expect_u16(&reader);
-	char data_buf[80];
-	size_t data_size = mpack_expect_bin_buf(&reader, data_buf, sizeof(data_buf));
-
-	printf("0x%02x\n", address);
-	printf("\"%.*s\"\n", data_size, data_buf);
-
-	return 0;
+	// at start of message
+	if (rdata == 0) {
+		// NOTE: This approach will crash and burn when target->addr can be read
+		// and target->length is past the end of the current buffer block. This is
+		// a highly unlikely scenario, as pb_read is called for each chunk of a TCP
+		// frame, and frames (should) include only one puzzle bus message.
+		target->addr = mpack_expect_u16(&reader);
+		target->length = rdata = mpack_expect_bin(&reader);
+		target->data = (char*) malloc(target->length);
+	}
+
+	// continue reading chunks of target->data until the amount of bytes
+	// specified in target->length
+	size_t to_read = MIN(mpack_reader_remaining(&reader, NULL), rdata);
+	char* data = target->data + target->length - rdata; // 'ol pointer arithmetic
+	mpack_read_bytes(&reader, data, to_read);
+	rdata -= to_read;
+
+	// if rdata = 0, the message was completely read
+	return rdata == 0;
 }
 
-int pb_write(struct pb_msg* target, char** buf, size_t* buf_sz) {
+bool pb_write(struct pb_msg* target, char** buf, size_t* buf_sz) {
 	mpack_writer_t writer;
 	mpack_writer_init_growable(&writer, buf, buf_sz);