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, 4 deletions

diff --git a/lib/sqfs/comp/lzo.c b/lib/sqfs/comp/lzo.c
index 9af3321..498c250 100644
--- a/lib/sqfs/comp/lzo.c
+++ b/lib/sqfs/comp/lzo.c
@@ -112,13 +112,16 @@ static int lzo_read_options(sqfs_compressor_t *base, sqfs_file_t *file)
 	return 0;
 }
 
-static ssize_t lzo_comp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
-			      size_t size, sqfs_u8 *out, size_t outsize)
+static sqfs_s32 lzo_comp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
+			       sqfs_u32 size, sqfs_u8 *out, sqfs_u32 outsize)
 {
 	lzo_compressor_t *lzo = (lzo_compressor_t *)base;
 	lzo_uint len = outsize;
 	int ret;
 
+	if (size >= 0x7FFFFFFF)
+		return 0;
+
 	if (lzo->algorithm == SQFS_LZO1X_999 &&
 	    lzo->level != SQFS_LZO_DEFAULT_LEVEL) {
 		ret = lzo1x_999_compress_level(in, size, out, &len,
@@ -138,13 +141,16 @@ static ssize_t lzo_comp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
 	return 0;
 }
 
-static ssize_t lzo_uncomp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
-				size_t size, sqfs_u8 *out, size_t outsize)
+static sqfs_s32 lzo_uncomp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
+				 sqfs_u32 size, sqfs_u8 *out, sqfs_u32 outsize)
 {
 	lzo_compressor_t *lzo = (lzo_compressor_t *)base;
 	lzo_uint len = outsize;
 	int ret;
 
+	if (outsize >= 0x7FFFFFFF)
+		return 0;
+
 	ret = lzo1x_decompress_safe(in, size, out, &len, lzo->buffer);
 
 	if (ret != LZO_E_OK)