Remove use of ssize_t from library API

ssize_t is only available on POSIX platforms and even there it is
only defined to hold at least -1 in the range of negative numbers.

This commit replaces ssize_t return types with sqfs_s32 and the
coresponding function arguments with sqfs_u32. Because the range
of positiv numbers for a signed 32 bit number is only half that of
the unsigned version, additional checks have to be added.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 10 insertions, 7 deletions

diff --git a/lib/sqfs/data_reader.c b/lib/sqfs/data_reader.c
index 0befb9d..12a8feb 100644
--- a/lib/sqfs/data_reader.c
+++ b/lib/sqfs/data_reader.c
@@ -40,8 +40,8 @@ static int get_block(sqfs_data_reader_t *data, sqfs_u64 off, sqfs_u32 size,
 		     size_t unpacked_size, sqfs_block_t **out)
 {
 	sqfs_block_t *blk = alloc_flex(sizeof(*blk), 1, unpacked_size);
-	size_t on_disk_size;
-	ssize_t ret;
+	sqfs_u32 on_disk_size;
+	sqfs_s32 ret;
 	int err;
 
 	if (blk == NULL)
@@ -264,14 +264,17 @@ int sqfs_data_reader_get_fragment(sqfs_data_reader_t *data,
 	return 0;
 }
 
-ssize_t sqfs_data_reader_read(sqfs_data_reader_t *data,
-			      const sqfs_inode_generic_t *inode,
-			      sqfs_u64 offset, void *buffer, size_t size)
+sqfs_s32 sqfs_data_reader_read(sqfs_data_reader_t *data,
+			       const sqfs_inode_generic_t *inode,
+			       sqfs_u64 offset, void *buffer, sqfs_u32 size)
 {
-	sqfs_u32 frag_idx, frag_off;
-	size_t i, diff, total = 0;
+	sqfs_u32 frag_idx, frag_off, diff, total = 0;
 	sqfs_u64 off, filesz;
 	char *ptr;
+	size_t i;
+
+	if (size >= 0x7FFFFFFF)
+		size = 0x7FFFFFFE;
 
 	/* work out file location and size */
 	sqfs_inode_get_file_size(inode, &filesz);