mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 11:37:35 +00:00
6f7d0cb1c3
This makes breaking changes to add underscores to many non-standard function names provided by the c library. MODE=tiny is now tinier and we now use smaller locks that are better for tiny apps in this mode. Some headers have been renamed to be in the same folder as the build package, so it'll be easier to know which build dependency is needed. Certain old misguided interfaces have been removed. Intel intrinsics headers are now listed in libc/isystem (but not in the amalgamation) to help further improve open source compatibility. Header complexity has also been reduced. Lastly, more shell scripts are now available.
40 lines
1.2 KiB
C
40 lines
1.2 KiB
C
#ifndef COSMOPOLITAN_LIBC_STR_TPDECODECB_H_
|
|
#define COSMOPOLITAN_LIBC_STR_TPDECODECB_H_
|
|
#include "libc/intrin/bsr.h"
|
|
#if !(__ASSEMBLER__ + __LINKER__ + 0)
|
|
|
|
/* TODO(jart): DELETE? */
|
|
|
|
/**
|
|
* Generic Thompson-Pike Varint Decoder.
|
|
* @return number of bytes successfully consumed or -1 w/ errno
|
|
* @note synchronization is performed
|
|
* @todo delete
|
|
*/
|
|
forceinline int tpdecodecb(wint_t *out, int first,
|
|
int get(void *arg, uint32_t i), void *arg) {
|
|
uint32_t wc, cb, need, msb, j, i = 1;
|
|
if (__builtin_expect((wc = first) == -1, 0)) return -1;
|
|
while (__builtin_expect((wc & 0b11000000) == 0b10000000, 0)) {
|
|
if ((wc = get(arg, i++)) == -1) return -1;
|
|
}
|
|
if (__builtin_expect(!(0 <= wc && wc <= 0x7F), 0)) {
|
|
msb = wc < 252 ? _bsr(~wc & 0xff) : 1;
|
|
need = 7 - msb;
|
|
wc &= ((1u << msb) - 1) | 0b00000011;
|
|
for (j = 1; j < need; ++j) {
|
|
if ((cb = get(arg, i++)) == -1) return -1;
|
|
if ((cb & 0b11000000) == 0b10000000) {
|
|
wc = wc << 6 | (cb & 0b00111111);
|
|
} else {
|
|
if (out) *out = u'\xFFFD';
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
if (__builtin_expect(!!out, 1)) *out = (wint_t)wc;
|
|
return i;
|
|
}
|
|
|
|
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
|
|
#endif /* COSMOPOLITAN_LIBC_STR_TPDECODECB_H_ */
|