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/* See LICENSE file for copyright and license details. */
#include "common.h"
/* XXX be smarter if using the same byteorder */
enum libsyscalls_error
libsyscalls_to_tracer_endian(const void *value_in, size_t in_offset,
const struct libsyscalls_datatype_description *type,
unsigned long long int *value_out)
{
const unsigned long long int limit = sizeof(long long int) / sizeof(char) * CHAR_BIT;
unsigned long long int bytebits, bytemask, byte, value, remmask, valmask;
unsigned long long int offset = in_offset, offset_byte, offset_bit, off;
const unsigned char *in = value_in;
size_t i;
if (!type || !value_in || !value_out || (unsigned long long int)type->width_in_bits > limit)
return LIBSYSCALLS_E_INVAL;
bytebits = (unsigned long long int)type->width_in_bits;
for (i = 0; !LIBSYSCALLS_IS_BYTEORDER_END_AT(type, i); i++)
if (type->byteorder[i] && (unsigned long long int)type->byteorder[i] < bytebits)
bytebits = (unsigned long long int)type->byteorder[i];
if (bytebits > limit)
return LIBSYSCALLS_E_INVAL;
else if (bytebits == limit)
bytemask = ~0ULL;
else
bytemask = (1ULL << bytebits) - 1ULL;
if ((unsigned long long int)type->width_in_bits == limit)
valmask = ~0ULL;
else
valmask = (1ULL << (unsigned long long int)type->width_in_bits) - 1ULL;
value = 0;
for (i = 0; !LIBSYSCALLS_IS_BYTEORDER_END_AT(type, i); i++) {
offset_byte = offset / CHAR_BIT;
offset_bit = offset % CHAR_BIT;
offset += bytebits;
byte = (unsigned long long int)in[offset_byte] >> offset_bit;
remmask = bytemask & (valmask >> type->byteorder[i]);
off = CHAR_BIT - offset_bit;
if (remmask >>= off) {
do {
byte |= (unsigned long long int)in[++offset_byte] << off;
off += CHAR_BIT;
} while (remmask >>= CHAR_BIT);
}
byte &= bytemask & (valmask >> type->byteorder[i]);
value |= byte << type->byteorder[i];
}
*value_out = value;
return LIBSYSCALLS_E_OK;
}
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