floatformat.c (get_field): Fix segfault with little-endian word order on 64-bit hosts.

* floatformat.c (get_field): Fix segfault with little-endian word
	order on 64-bit hosts.
	(put_field): Likewise.
	(min): Move definition.

From-SVN: r118552
This commit is contained in:
Julian Brown 2006-11-07 15:16:07 +00:00 committed by Julian Brown
parent d81ecf52ff
commit 36b8206084
2 changed files with 56 additions and 60 deletions

View File

@ -1,3 +1,10 @@
2006-11-07 Julian Brown <julian@codesourcery.com>
* floatformat.c (get_field): Fix segfault with little-endian word
order on 64-bit hosts.
(put_field): Likewise.
(min): Move definition.
2006-10-26 Danny Smith <dannysmith@users.sourceforge.net>
pex-win32.c (argv_to_cmdline): Replace xmalloc with XNEWVEC.

View File

@ -249,53 +249,51 @@ const struct floatformat floatformat_ia64_quad_little =
floatformat_always_valid
};
#ifndef min
#define min(a, b) ((a) < (b) ? (a) : (b))
#endif
/* Extract a field which starts at START and is LEN bits long. DATA and
TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
static unsigned long
get_field (const unsigned char *data, enum floatformat_byteorders order,
unsigned int total_len, unsigned int start, unsigned int len)
{
unsigned long result;
unsigned long result = 0;
unsigned int cur_byte;
int cur_bitshift;
int lo_bit, hi_bit, cur_bitshift = 0;
int nextbyte = (order == floatformat_little) ? 1 : -1;
/* Start is in big-endian bit order! Fix that first. */
start = total_len - (start + len);
/* Start at the least significant part of the field. */
cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT;
if (order == floatformat_little)
cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) - cur_byte - 1;
cur_bitshift =
((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT;
result = *(data + cur_byte) >> (-cur_bitshift);
cur_bitshift += FLOATFORMAT_CHAR_BIT;
if (order == floatformat_little)
++cur_byte;
cur_byte = start / FLOATFORMAT_CHAR_BIT;
else
--cur_byte;
cur_byte = (total_len - start - 1) / FLOATFORMAT_CHAR_BIT;
/* Move towards the most significant part of the field. */
while ((unsigned int) cur_bitshift < len)
lo_bit = start % FLOATFORMAT_CHAR_BIT;
hi_bit = min (lo_bit + len, FLOATFORMAT_CHAR_BIT);
do
{
if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT)
/* This is the last byte; zero out the bits which are not part of
this field. */
result |=
(*(data + cur_byte) & ((1 << (len - cur_bitshift)) - 1))
<< cur_bitshift;
else
result |= *(data + cur_byte) << cur_bitshift;
cur_bitshift += FLOATFORMAT_CHAR_BIT;
if (order == floatformat_little)
++cur_byte;
else
--cur_byte;
unsigned int shifted = *(data + cur_byte) >> lo_bit;
unsigned int bits = hi_bit - lo_bit;
unsigned int mask = (1 << bits) - 1;
result |= (shifted & mask) << cur_bitshift;
len -= bits;
cur_bitshift += bits;
cur_byte += nextbyte;
lo_bit = 0;
hi_bit = min (len, FLOATFORMAT_CHAR_BIT);
}
while (len != 0);
return result;
}
#ifndef min
#define min(a, b) ((a) < (b) ? (a) : (b))
#endif
/* Convert from FMT to a double.
FROM is the address of the extended float.
Store the double in *TO. */
@ -428,43 +426,34 @@ put_field (unsigned char *data, enum floatformat_byteorders order,
unsigned long stuff_to_put)
{
unsigned int cur_byte;
int cur_bitshift;
int lo_bit, hi_bit;
int nextbyte = (order == floatformat_little) ? 1 : -1;
/* Start is in big-endian bit order! Fix that first. */
start = total_len - (start + len);
/* Start at the least significant part of the field. */
cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT;
if (order == floatformat_little)
cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) - cur_byte - 1;
cur_bitshift =
((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT;
*(data + cur_byte) &=
~(((1 << ((start + len) % FLOATFORMAT_CHAR_BIT)) - 1) << (-cur_bitshift));
*(data + cur_byte) |=
(stuff_to_put & ((1 << FLOATFORMAT_CHAR_BIT) - 1)) << (-cur_bitshift);
cur_bitshift += FLOATFORMAT_CHAR_BIT;
if (order == floatformat_little)
++cur_byte;
cur_byte = start / FLOATFORMAT_CHAR_BIT;
else
--cur_byte;
cur_byte = (total_len - start - 1) / FLOATFORMAT_CHAR_BIT;
/* Move towards the most significant part of the field. */
while ((unsigned int) cur_bitshift < len)
lo_bit = start % FLOATFORMAT_CHAR_BIT;
hi_bit = min (lo_bit + len, FLOATFORMAT_CHAR_BIT);
do
{
if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT)
{
/* This is the last byte. */
*(data + cur_byte) &=
~((1 << (len - cur_bitshift)) - 1);
*(data + cur_byte) |= (stuff_to_put >> cur_bitshift);
}
else
*(data + cur_byte) = ((stuff_to_put >> cur_bitshift)
& ((1 << FLOATFORMAT_CHAR_BIT) - 1));
cur_bitshift += FLOATFORMAT_CHAR_BIT;
if (order == floatformat_little)
++cur_byte;
else
--cur_byte;
unsigned char *byte_ptr = data + cur_byte;
unsigned int bits = hi_bit - lo_bit;
unsigned int mask = ((1 << bits) - 1) << lo_bit;
*byte_ptr = (*byte_ptr & ~mask) | ((stuff_to_put << lo_bit) & mask);
stuff_to_put >>= bits;
len -= bits;
cur_byte += nextbyte;
lo_bit = 0;
hi_bit = min (len, FLOATFORMAT_CHAR_BIT);
}
while (len != 0);
}
/* The converse: convert the double *FROM to an extended float