diff options
Diffstat (limited to 'Utilities/cmlibarchive/libarchive/archive_endian.h')
| -rw-r--r-- | Utilities/cmlibarchive/libarchive/archive_endian.h | 36 |
1 files changed, 32 insertions, 4 deletions
diff --git a/Utilities/cmlibarchive/libarchive/archive_endian.h b/Utilities/cmlibarchive/libarchive/archive_endian.h index bbf58fd10..3c039f702 100644 --- a/Utilities/cmlibarchive/libarchive/archive_endian.h +++ b/Utilities/cmlibarchive/libarchive/archive_endian.h @@ -64,7 +64,13 @@ archive_be16dec(const void *pp) { unsigned char const *p = (unsigned char const *)pp; - return ((p[0] << 8) | p[1]); + /* Store into unsigned temporaries before left shifting, to avoid + promotion to signed int and then left shifting into the sign bit, + which is undefined behaviour. */ + unsigned int p1 = p[1]; + unsigned int p0 = p[0]; + + return ((p0 << 8) | p1); } static inline uint32_t @@ -72,7 +78,15 @@ archive_be32dec(const void *pp) { unsigned char const *p = (unsigned char const *)pp; - return ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]); + /* Store into unsigned temporaries before left shifting, to avoid + promotion to signed int and then left shifting into the sign bit, + which is undefined behaviour. */ + unsigned int p3 = p[3]; + unsigned int p2 = p[2]; + unsigned int p1 = p[1]; + unsigned int p0 = p[0]; + + return ((p0 << 24) | (p1 << 16) | (p2 << 8) | p3); } static inline uint64_t @@ -88,7 +102,13 @@ archive_le16dec(const void *pp) { unsigned char const *p = (unsigned char const *)pp; - return ((p[1] << 8) | p[0]); + /* Store into unsigned temporaries before left shifting, to avoid + promotion to signed int and then left shifting into the sign bit, + which is undefined behaviour. */ + unsigned int p1 = p[1]; + unsigned int p0 = p[0]; + + return ((p1 << 8) | p0); } static inline uint32_t @@ -96,7 +116,15 @@ archive_le32dec(const void *pp) { unsigned char const *p = (unsigned char const *)pp; - return ((p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]); + /* Store into unsigned temporaries before left shifting, to avoid + promotion to signed int and then left shifting into the sign bit, + which is undefined behaviour. */ + unsigned int p3 = p[3]; + unsigned int p2 = p[2]; + unsigned int p1 = p[1]; + unsigned int p0 = p[0]; + + return ((p3 << 24) | (p2 << 16) | (p1 << 8) | p0); } static inline uint64_t |