tar: avoid casts in tar_checksum.

* (tar_checksum): recode to avoid casts.
  * (tar_from_header): likewise.

Sync with GNU tar 1521d3dae01f91606c639eb745ea565ef723e38d.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
This commit is contained in:
Andrew Borodin 2024-09-01 14:09:07 +03:00
parent 7d8deb89c8
commit b6483b8a47
2 changed files with 20 additions and 14 deletions

View File

@ -464,7 +464,10 @@ tar_from_header (const char *where0, size_t digs, char const *type, intmax_t min
while (TRUE)
{
value = (value << LG_256) + (unsigned char) *where++;
unsigned char uc;
uc = *where++;
value = (value << LG_256) + uc;
if (where == lim)
break;

View File

@ -327,39 +327,42 @@ tar_available_space_after (const union block *pointer)
static read_header
tar_checksum (const union block *header)
{
size_t i;
int i;
int unsigned_sum = 0; /* the POSIX one :-) */
int signed_sum = 0; /* the Sun one :-( */
int recorded_sum;
int parsed_sum;
const char *p = header->buffer;
for (i = sizeof (*header); i-- != 0;)
for (i = 0; i < sizeof (*header); i++)
{
unsigned_sum += (unsigned char) *p;
signed_sum += (signed char) (*p++);
unsigned char uc = header->buffer[i];
signed char sc = header->buffer[i];
unsigned_sum += uc;
signed_sum += sc;
}
if (unsigned_sum == 0)
return HEADER_ZERO_BLOCK;
/* Adjust checksum to count the "chksum" field as blanks. */
for (i = sizeof (header->header.chksum); i-- != 0;)
for (i = 0; i < sizeof (header->header.chksum); i++)
{
unsigned_sum -= (unsigned char) header->header.chksum[i];
signed_sum -= (signed char) (header->header.chksum[i]);
unsigned char uc = header->header.chksum[i];
signed char sc = header->header.chksum[i];
unsigned_sum -= uc;
signed_sum -= sc;
}
unsigned_sum += ' ' * sizeof (header->header.chksum);
signed_sum += ' ' * sizeof (header->header.chksum);
parsed_sum =
recorded_sum =
tar_from_header (header->header.chksum, sizeof (header->header.chksum), NULL, 0,
INT_MAX, TRUE);
if (parsed_sum < 0)
return HEADER_FAILURE;
recorded_sum = parsed_sum;
if (recorded_sum < 0)
return HEADER_FAILURE;
if (unsigned_sum != recorded_sum && signed_sum != recorded_sum)
return HEADER_FAILURE;