From 5975b3707bcae469d54066a9883964fa345c5ac4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nuno=20S=C3=A1?= <nuno.sa@analog.com>
Date: Wed, 5 Feb 2025 17:17:15 +0000
Subject: [PATCH] test_7

---
 iiod/ops.h       |  2 ++
 iiod/responder.c | 30 ++++++++++++++++++++++++++----
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/iiod/ops.h b/iiod/ops.h
index e4d9681e5..82371d982 100644
--- a/iiod/ops.h
+++ b/iiod/ops.h
@@ -64,6 +64,8 @@ struct block_entry {
 	bool cyclic;
 	int dmabuf_fd;
 	int ep_fd;
+	uint16_t refcnt;
+	bool dead;
 };
 
 struct buffer_entry {
diff --git a/iiod/responder.c b/iiod/responder.c
index 91aceb55b..4169e3230 100644
--- a/iiod/responder.c
+++ b/iiod/responder.c
@@ -36,12 +36,25 @@ struct iio_mutex *evlist_lock;
 
 static void free_block_entry(struct block_entry *entry)
 {
+	printf("Block Entry (%p): %u freed.\n", entry, entry->idx);
 	iiod_io_cancel(entry->io);
 	iiod_io_unref(entry->io);
 	iio_block_destroy(entry->block);
 	free(entry);
 }
 
+static void block_entry_put(struct block_entry *entry)
+{
+	entry->refcnt--;
+	if (entry->refcnt == 0)
+		free_block_entry(entry);
+}
+
+static void block_entry_get(struct block_entry *entry)
+{
+	entry->refcnt++;
+}
+
 static void free_buffer_entry(struct buffer_entry *entry)
 {
 	struct block_entry *block_entry, *block_next;
@@ -61,7 +74,8 @@ static void free_buffer_entry(struct buffer_entry *entry)
 	for (block_entry = SLIST_FIRST(&entry->blocklist);
 	     block_entry; block_entry = block_next) {
 		block_next = SLIST_NEXT(block_entry, entry);
-		free_block_entry(block_entry);
+		block_entry_put(block_entry);
+		//free_block_entry(block_entry);
 	}
 
 	iio_mutex_unlock(entry->lock);
@@ -348,6 +362,9 @@ static int buffer_dequeue_block(void *priv, void *d)
 out_send_response:
 	printf("Dequeue block(%u) send response\n", entry->idx);
 	iiod_io_send_response(entry->io, ret, &data, nb_data);
+	iio_mutex_lock(buffer->lock);
+	block_entry_put(entry);
+	iio_mutex_unlock(buffer->lock);
 	return 0;
 }
 
@@ -531,6 +548,7 @@ static struct iio_block * get_iio_block(struct parser_pdata *pdata,
 	SLIST_FOREACH(entry, &entry_buf->blocklist, entry) {
 		if (entry->idx == cmd->code >> 16) {
 			block = entry->block;
+			block_entry_get(entry);
 			break;
 		}
 	}
@@ -549,7 +567,6 @@ static void handle_free_buffer(struct parser_pdata *pdata,
 {
 	struct iiod_io *io = iiod_command_get_default_io(cmd_data);
 	const struct iio_device *dev;
-	struct block_entry *block_entry, *block_next;
 	struct buffer_entry *entry, *buf_entry;
 	struct iio_buffer *buf;
 	int ret;
@@ -673,6 +690,9 @@ static void handle_create_block(struct parser_pdata *pdata,
 		/* No error? This block already exists, so return
 		 * -EINVAL. */
 		ret = -EINVAL;
+		iio_mutex_lock(buf_entry->lock);
+		block_entry_put(entry);
+		iio_mutex_unlock(buf_entry->lock);
 		goto out_send_response;
 	}
 
@@ -691,6 +711,7 @@ static void handle_create_block(struct parser_pdata *pdata,
 	entry->block = block;
 	entry->io = io;
 	entry->idx = cmd->code >> 16;
+	entry->refcnt = 1;
 
 	if (WITH_IIOD_USB_DMABUF && pdata->is_usb) {
 		entry->dmabuf_fd = iio_block_get_dmabuf_fd(block);
@@ -757,12 +778,13 @@ static void handle_free_block(struct parser_pdata *pdata,
 
 		SLIST_REMOVE(&buf_entry->blocklist, entry, block_entry, entry);
 
-		printf("Block (%p): %u freed.\n", entry, entry->idx);
-		free_block_entry(entry);
+		printf("Block (%p): %u put.\n", entry, entry->idx);
+		block_entry_put(entry);
 		ret = 0;
 		break;
 	}
 
+	//block_entry_put(entry);
 	iio_mutex_unlock(buf_entry->lock);
 
 	IIO_DEBUG("Block %u freed.\n", cmd->code);