1 files changed, 30 insertions, 16 deletions

diff --git a/src/file.c b/src/file.c
index 065b5ea..a5d6291 100644
--- a/src/file.c
+++ b/src/file.c
@@ -663,12 +663,12 @@ static int chunk_copy_internal_local_to_remote_async(struct chunk *c, int fd,
 						     sftp_file sf, int nr_ahead,
 						     size_t *counter)
 {
-	size_t read_bytes, remaind, thrown;
+	ssize_t read_bytes, remaind, thrown;
 	char buf[XFER_BUF_SIZE];
 	int idx, ret;
 	struct {
 		int id;
-		size_t len;
+		ssize_t len;
 	} reqs[nr_ahead];
 
 	if (c->len == 0)
@@ -688,10 +688,10 @@ static int chunk_copy_internal_local_to_remote_async(struct chunk *c, int fd,
 			       c->f->dst_path, sftp_get_error(sf->sftp));
 			return -1;
 		}
+		thrown -= reqs[idx].len;
 	}
 
-	for (idx = 0; remaind > 0;) {
-		/* TODO: should be non-blocking */
+	for (idx = 0; remaind > 0; idx = (idx + 1) % nr_ahead) {
 		ret = sftp_async_write_end(sf, reqs[idx].id, 1);
 		if (ret != SSH_OK) {
 			pr_err("sftp_async_write_end failed for %s: %d\n",
@@ -699,13 +699,16 @@ static int chunk_copy_internal_local_to_remote_async(struct chunk *c, int fd,
 			return -1;
 		}
 
-		remaind -= reqs[idx].len;
 		*counter += reqs[idx].len;
+		remaind -= reqs[idx].len;
 
-		if (remaind == 0)
+		if (remaind <= 0)
 			break;
 
-		reqs[idx].len = min(remaind, sizeof(buf));
+		if (thrown <= 0)
+			continue;
+
+		reqs[idx].len = min(thrown, sizeof(buf));
 		read_bytes = read(fd, buf, reqs[idx].len);
 		if (read_bytes < 0) {
 			pr_err("read from %s failed: %s\n", c->f->src_path, strerrno());
@@ -718,8 +721,14 @@ static int chunk_copy_internal_local_to_remote_async(struct chunk *c, int fd,
 			       c->f->dst_path, sftp_get_error(sf->sftp));
 			return -1;
 		}
+		thrown -= reqs[idx].len;
+	}
 
-		idx = (idx + 1) % nr_ahead;
+	if (remaind < 0) {
+		pr_err("invalid remaind bytes %ld. last async_write_end bytes %lu. "
+		       "last read bytes %ld\n",
+		       remaind, reqs[idx].len, read_bytes);
+		return -1;
 	}
 
 	return 0;
@@ -734,7 +743,7 @@ static int chunk_copy_internal_remote_to_local(struct chunk *c, int fd, sftp_fil
 	int idx;
 	struct {
 		int id;
-		size_t len;
+		ssize_t len;
 	} reqs[nr_ahead];
 
 	/* TODO: sftp_buf_sz has no effect on remote to local copy. we
@@ -761,19 +770,17 @@ static int chunk_copy_internal_remote_to_local(struct chunk *c, int fd, sftp_fil
 		thrown -= reqs[idx].len;
 	}
 
-	for (idx = 0; remaind > 0;) {
-
+	for (idx = 0; remaind > 0; idx = (idx + 1) % nr_ahead) {
 		read_bytes = sftp_async_read(sf, buf, reqs[idx].len, reqs[idx].id);
 		if (read_bytes == SSH_ERROR) {
 			pr_err("sftp_async_read failed: %d\n", sftp_get_error(sf->sftp));
 			return -1;
 		}
 
-		remaind -= read_bytes;
-
-		if (remaind > 0) {
-			reqs[idx].len = min(remaind, sizeof(buf));
+		if (thrown > 0) {
+			reqs[idx].len = min(thrown, sizeof(buf));
 			reqs[idx].id = sftp_async_read_begin(sf, reqs[idx].len);
+			thrown -= reqs[idx].len;
 		}
 
 		write_bytes = write(fd, buf, read_bytes);
@@ -788,7 +795,14 @@ static int chunk_copy_internal_remote_to_local(struct chunk *c, int fd, sftp_fil
 		}
 
 		*counter += write_bytes;
-		idx = (idx + 1) % nr_ahead;
+		remaind -= read_bytes;
+	}
+
+	if (remaind < 0) {
+		pr_err("invalid remaind bytes %ld. last async_read bytes %ld. "
+		       "last write bytes %ld\n",
+		       remaind, read_bytes, write_bytes);
+		return -1;
 	}
 
 	return 0;