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#include <assert.h>
#include <libnu/ducet.h>
#include <libnu/udb.h>
#ifdef NU_WITH_DUCET
#include "gen/_ducet.c"
#ifndef NU_DISABLE_CONTRACTIONS
# include "gen/_ducet_switch.c"
#else
const size_t _NU_DUCET_CONTRACTIONS = 0;
#endif
static size_t _nu_ducet_weights_count() {
return NU_DUCET_G_SIZE + _NU_DUCET_CONTRACTIONS;
}
int32_t nu_ducet_weight(uint32_t codepoint, int32_t *weight, void *context) {
(void)(weight);
(void)(context);
assert(_nu_ducet_weights_count() < 0x7FFFFFFF - 0x10FFFF);
#ifndef NU_DISABLE_CONTRACTIONS
int32_t switch_value = _nu_ducet_weight_switch(codepoint, weight, context);
/* weight switch should return weight (if any) and fill value of *weight
* with fallback (if needed). returned value of 0 is impossible result - this
* special case is already handled above, this return value indicates that switch
* couldn't find weight for a codepoint */
if (switch_value != 0) {
return switch_value;
}
#endif
/* special case switch after contractions switch
* to let state-machine figure out its state on abort */
if (codepoint == 0) {
return 0;
}
uint32_t mph_value = nu_udb_lookup_value(codepoint, NU_DUCET_G, NU_DUCET_G_SIZE,
NU_DUCET_VALUES_C, NU_DUCET_VALUES_I);
return (mph_value != 0
? (int32_t)(mph_value)
: (int32_t)(codepoint + _nu_ducet_weights_count()));
/* ISO/IEC 14651 requests that codepoints with undefined weight should be
* sorted before max weight in collation table. This way all codepoints
* defined in ducet would have weight under a value of _nu_ducet_weights_count(),
* all undefined codepoints would have weight under
* 0x10FFFF + _nu_ducet_weights_count() - 1, max weight will be
* 0x10FFFF + _nu_ducet_weights_count() */
/* Regarding integer overflow:
*
* int32_t can hold 0xFFFFFFFF / 2 = 0x7FFFFFFF positive numbers, this
* function can safely offset codepoint value up to +2146369536 without
* risk of overflow. Thus max collation table size supported is
* 2146369536 (0x7FFFFFFF - 0x10FFFF) */
}
#endif /* NU_WITH_DUCET */
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