X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=send-stream.c;h=78f2571ae40be82cbce1b7eb40e80c5293acd6c8;hb=335b7011352bfe27d59094d622abe111177021d4;hp=3720e7dfec0cc382f1f97a5cb1c7f2121b0a957f;hpb=4c066138426be59c9f8c6956f4d02c941042c55c;p=platform%2Fupstream%2Fbtrfs-progs.git

diff --git a/send-stream.c b/send-stream.c
index 3720e7d..78f2571 100644
--- a/send-stream.c
+++ b/send-stream.c
@@ -33,10 +33,23 @@ struct btrfs_send_stream {
 	struct btrfs_tlv_header *cmd_attrs[BTRFS_SEND_A_MAX + 1];
 	u32 version;
 
+	/*
+	 * end of last successful read, equivalent to start of current
+	 * malformated part of block
+	 */
+	size_t stream_pos;
+
 	struct btrfs_send_ops *ops;
 	void *user;
 };
 
+/*
+ * Read len bytes to buf.
+ * Return:
+ *   0 - success
+ * < 0 - negative errno in case of error
+ * > 0 - no data read, EOF
+ */
 static int read_buf(struct btrfs_send_stream *sctx, char *buf, size_t len)
 {
 	int ret;
@@ -54,13 +67,20 @@ static int read_buf(struct btrfs_send_stream *sctx, char *buf, size_t len)
 		}
 		if (rbytes == 0) {
 			ret = 1;
-			goto out;
+			goto out_eof;
 		}
 		pos += rbytes;
 	}
-
 	ret = 0;
 
+out_eof:
+	if (0 < pos && pos < len) {
+		error("short read from stream: expected %zu read %zu", len, pos);
+		ret = -EIO;
+	} else {
+		sctx->stream_pos += pos;
+	}
+
 out:
 	return ret;
 }
@@ -68,11 +88,15 @@ out:
 /*
  * Reads a single command from kernel space and decodes the TLV's into
  * sctx->cmd_attrs
+ *
+ * Returns:
+ *   0 - success
+ * < 0 - an error in the command
  */
 static int read_cmd(struct btrfs_send_stream *sctx)
 {
 	int ret;
-	int cmd;
+	u16 cmd;
 	u32 cmd_len;
 	char *data;
 	u32 pos;
@@ -158,7 +182,7 @@ out:
 static int tlv_get(struct btrfs_send_stream *sctx, int attr, void **data, int *len)
 {
 	int ret;
-	struct btrfs_tlv_header *h;
+	struct btrfs_tlv_header *hdr;
 
 	if (attr <= 0 || attr > BTRFS_SEND_A_MAX) {
 		error("invalid attribute requested, attr = %d", attr);
@@ -166,15 +190,15 @@ static int tlv_get(struct btrfs_send_stream *sctx, int attr, void **data, int *l
 		goto out;
 	}
 
-	h = sctx->cmd_attrs[attr];
-	if (!h) {
+	hdr = sctx->cmd_attrs[attr];
+	if (!hdr) {
 		error("attribute %d requested but not present", attr);
 		ret = -ENOENT;
 		goto out;
 	}
 
-	*len = le16_to_cpu(h->tlv_len);
-	*data = h + 1;
+	*len = le16_to_cpu(hdr->tlv_len);
+	*data = hdr + 1;
 
 	ret = 0;
 
@@ -462,12 +486,13 @@ int btrfs_read_and_process_send_stream(int fd,
 	sctx.fd = fd;
 	sctx.ops = ops;
 	sctx.user = user;
+	sctx.stream_pos = 0;
 
 	ret = read_buf(&sctx, (char*)&hdr, sizeof(hdr));
 	if (ret < 0)
 		goto out;
 	if (ret) {
-		ret = 1;
+		ret = -ENODATA;
 		goto out;
 	}