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Improve Lua and JSON serialization

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This commit is contained in:
Justine Tunney 2022-07-12 23:31:06 -07:00
parent 3027d67037
commit e3cd476a9b
20 changed files with 1041 additions and 476 deletions
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46
libc/fmt/formatflex64.c
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@ -16,48 +16,24 @@
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/fmt/fmt.h"
#include "libc/bits/popcnt.h"
#include "libc/fmt/itoa.h"
#include "libc/math.h"
static inline int CountZeroesHex(uint64_t x) {
int n;
for (n = 0; x;) {
if (!(x & 15)) {
++n;
}
x >>= 4;
}
return n;
}
static inline int CountZeroesDec(int64_t s) {
int n, r;
uint64_t x;
x = s >= 0 ? s : -(uint64_t)s;
for (n = 0; x;) {
r = x % 10;
x = x / 10;
if (!r) ++n;
}
return n;
}
/**
* Formats integer using decimal or hexadecimal.
*
* We choose hex vs. decimal based on whichever one has the most zeroes.
* We only bother counting zeroes for numbers outside -256 ≤ 𝑥 ≤ 256.
* This formats as int64 signed decimal. However it's a:
*
* 1. positive number
* 2. with population count of 1
* 3. and a magnitude of at least 256
*
* Then we switch to hex notation to make the number more readable.
*/
char *FormatFlex64(char p[hasatleast 24], int64_t x, char z) {
int zhex, zdec;
if (-256 <= x && x <= 256) goto UseDecimal;
zhex = CountZeroesHex(x) * 16;
zdec = CountZeroesDec(x) * 10;
if (zdec >= zhex) {
UseDecimal:
return FormatInt64(p, x);
} else {
if (x >= 256 && popcnt(x) == 1) {
return FormatHex64(p, x, z);
} else {
return FormatInt64(p, x);
}
}