summaryrefslogtreecommitdiffstats
path: root/fluent-bit/lib/luajit-3065c9/src/lj_strscan.c
diff options
context:
space:
mode:
Diffstat (limited to 'fluent-bit/lib/luajit-3065c9/src/lj_strscan.c')
-rw-r--r--fluent-bit/lib/luajit-3065c9/src/lj_strscan.c558
1 files changed, 0 insertions, 558 deletions
diff --git a/fluent-bit/lib/luajit-3065c9/src/lj_strscan.c b/fluent-bit/lib/luajit-3065c9/src/lj_strscan.c
deleted file mode 100644
index 1d1c1c74..00000000
--- a/fluent-bit/lib/luajit-3065c9/src/lj_strscan.c
+++ /dev/null
@@ -1,558 +0,0 @@
-/*
-** String scanning.
-** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h
-*/
-
-#include <math.h>
-
-#define lj_strscan_c
-#define LUA_CORE
-
-#include "lj_obj.h"
-#include "lj_char.h"
-#include "lj_strscan.h"
-
-/* -- Scanning numbers ---------------------------------------------------- */
-
-/*
-** Rationale for the builtin string to number conversion library:
-**
-** It removes a dependency on libc's strtod(), which is a true portability
-** nightmare. Mainly due to the plethora of supported OS and toolchain
-** combinations. Sadly, the various implementations
-** a) are often buggy, incomplete (no hex floats) and/or imprecise,
-** b) sometimes crash or hang on certain inputs,
-** c) return non-standard NaNs that need to be filtered out, and
-** d) fail if the locale-specific decimal separator is not a dot,
-** which can only be fixed with atrocious workarounds.
-**
-** Also, most of the strtod() implementations are hopelessly bloated,
-** which is not just an I-cache hog, but a problem for static linkage
-** on embedded systems, too.
-**
-** OTOH the builtin conversion function is very compact. Even though it
-** does a lot more, like parsing long longs, octal or imaginary numbers
-** and returning the result in different formats:
-** a) It needs less than 3 KB (!) of machine code (on x64 with -Os),
-** b) it doesn't perform any dynamic allocation and,
-** c) it needs only around 600 bytes of stack space.
-**
-** The builtin function is faster than strtod() for typical inputs, e.g.
-** "123", "1.5" or "1e6". Arguably, it's slower for very large exponents,
-** which are not very common (this could be fixed, if needed).
-**
-** And most importantly, the builtin function is equally precise on all
-** platforms. It correctly converts and rounds any input to a double.
-** If this is not the case, please send a bug report -- but PLEASE verify
-** that the implementation you're comparing to is not the culprit!
-**
-** The implementation quickly pre-scans the entire string first and
-** handles simple integers on-the-fly. Otherwise, it dispatches to the
-** base-specific parser. Hex and octal is straightforward.
-**
-** Decimal to binary conversion uses a fixed-length circular buffer in
-** base 100. Some simple cases are handled directly. For other cases, the
-** number in the buffer is up-scaled or down-scaled until the integer part
-** is in the proper range. Then the integer part is rounded and converted
-** to a double which is finally rescaled to the result. Denormals need
-** special treatment to prevent incorrect 'double rounding'.
-*/
-
-/* Definitions for circular decimal digit buffer (base 100 = 2 digits/byte). */
-#define STRSCAN_DIG 1024
-#define STRSCAN_MAXDIG 800 /* 772 + extra are sufficient. */
-#define STRSCAN_DDIG (STRSCAN_DIG/2)
-#define STRSCAN_DMASK (STRSCAN_DDIG-1)
-#define STRSCAN_MAXEXP (1 << 20)
-
-/* Helpers for circular buffer. */
-#define DNEXT(a) (((a)+1) & STRSCAN_DMASK)
-#define DPREV(a) (((a)-1) & STRSCAN_DMASK)
-#define DLEN(lo, hi) ((int32_t)(((lo)-(hi)) & STRSCAN_DMASK))
-
-#define casecmp(c, k) (((c) | 0x20) == k)
-
-/* Final conversion to double. */
-static void strscan_double(uint64_t x, TValue *o, int32_t ex2, int32_t neg)
-{
- double n;
-
- /* Avoid double rounding for denormals. */
- if (LJ_UNLIKELY(ex2 <= -1075 && x != 0)) {
- /* NYI: all of this generates way too much code on 32 bit CPUs. */
-#if (defined(__GNUC__) || defined(__clang__)) && LJ_64
- int32_t b = (int32_t)(__builtin_clzll(x)^63);
-#else
- int32_t b = (x>>32) ? 32+(int32_t)lj_fls((uint32_t)(x>>32)) :
- (int32_t)lj_fls((uint32_t)x);
-#endif
- if ((int32_t)b + ex2 <= -1023 && (int32_t)b + ex2 >= -1075) {
- uint64_t rb = (uint64_t)1 << (-1075-ex2);
- if ((x & rb) && ((x & (rb+rb+rb-1)))) x += rb+rb;
- x = (x & ~(rb+rb-1));
- }
- }
-
- /* Convert to double using a signed int64_t conversion, then rescale. */
- lj_assertX((int64_t)x >= 0, "bad double conversion");
- n = (double)(int64_t)x;
- if (neg) n = -n;
- if (ex2) n = ldexp(n, ex2);
- o->n = n;
-}
-
-/* Parse hexadecimal number. */
-static StrScanFmt strscan_hex(const uint8_t *p, TValue *o,
- StrScanFmt fmt, uint32_t opt,
- int32_t ex2, int32_t neg, uint32_t dig)
-{
- uint64_t x = 0;
- uint32_t i;
-
- /* Scan hex digits. */
- for (i = dig > 16 ? 16 : dig ; i; i--, p++) {
- uint32_t d = (*p != '.' ? *p : *++p); if (d > '9') d += 9;
- x = (x << 4) + (d & 15);
- }
-
- /* Summarize rounding-effect of excess digits. */
- for (i = 16; i < dig; i++, p++)
- x |= ((*p != '.' ? *p : *++p) != '0'), ex2 += 4;
-
- /* Format-specific handling. */
- switch (fmt) {
- case STRSCAN_INT:
- if (!(opt & STRSCAN_OPT_TONUM) && x < 0x80000000u+neg &&
- !(x == 0 && neg)) {
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_INT; /* Fast path for 32 bit integers. */
- }
- if (!(opt & STRSCAN_OPT_C)) { fmt = STRSCAN_NUM; break; }
- /* fallthrough */
- case STRSCAN_U32:
- if (dig > 8) return STRSCAN_ERROR;
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_U32;
- case STRSCAN_I64:
- case STRSCAN_U64:
- if (dig > 16) return STRSCAN_ERROR;
- o->u64 = neg ? (uint64_t)-(int64_t)x : x;
- return fmt;
- default:
- break;
- }
-
- /* Reduce range, then convert to double. */
- if ((x & U64x(c0000000,0000000))) { x = (x >> 2) | (x & 3); ex2 += 2; }
- strscan_double(x, o, ex2, neg);
- return fmt;
-}
-
-/* Parse octal number. */
-static StrScanFmt strscan_oct(const uint8_t *p, TValue *o,
- StrScanFmt fmt, int32_t neg, uint32_t dig)
-{
- uint64_t x = 0;
-
- /* Scan octal digits. */
- if (dig > 22 || (dig == 22 && *p > '1')) return STRSCAN_ERROR;
- while (dig-- > 0) {
- if (!(*p >= '0' && *p <= '7')) return STRSCAN_ERROR;
- x = (x << 3) + (*p++ & 7);
- }
-
- /* Format-specific handling. */
- switch (fmt) {
- case STRSCAN_INT:
- if (x >= 0x80000000u+neg) fmt = STRSCAN_U32;
- /* fallthrough */
- case STRSCAN_U32:
- if ((x >> 32)) return STRSCAN_ERROR;
- o->i = neg ? -(int32_t)x : (int32_t)x;
- break;
- default:
- case STRSCAN_I64:
- case STRSCAN_U64:
- o->u64 = neg ? (uint64_t)-(int64_t)x : x;
- break;
- }
- return fmt;
-}
-
-/* Parse decimal number. */
-static StrScanFmt strscan_dec(const uint8_t *p, TValue *o,
- StrScanFmt fmt, uint32_t opt,
- int32_t ex10, int32_t neg, uint32_t dig)
-{
- uint8_t xi[STRSCAN_DDIG], *xip = xi;
-
- if (dig) {
- uint32_t i = dig;
- if (i > STRSCAN_MAXDIG) {
- ex10 += (int32_t)(i - STRSCAN_MAXDIG);
- i = STRSCAN_MAXDIG;
- }
- /* Scan unaligned leading digit. */
- if (((ex10^i) & 1))
- *xip++ = ((*p != '.' ? *p : *++p) & 15), i--, p++;
- /* Scan aligned double-digits. */
- for ( ; i > 1; i -= 2) {
- uint32_t d = 10 * ((*p != '.' ? *p : *++p) & 15); p++;
- *xip++ = d + ((*p != '.' ? *p : *++p) & 15); p++;
- }
- /* Scan and realign trailing digit. */
- if (i) *xip++ = 10 * ((*p != '.' ? *p : *++p) & 15), ex10--, dig++, p++;
-
- /* Summarize rounding-effect of excess digits. */
- if (dig > STRSCAN_MAXDIG) {
- do {
- if ((*p != '.' ? *p : *++p) != '0') { xip[-1] |= 1; break; }
- p++;
- } while (--dig > STRSCAN_MAXDIG);
- dig = STRSCAN_MAXDIG;
- } else { /* Simplify exponent. */
- while (ex10 > 0 && dig <= 18) *xip++ = 0, ex10 -= 2, dig += 2;
- }
- } else { /* Only got zeros. */
- ex10 = 0;
- xi[0] = 0;
- }
-
- /* Fast path for numbers in integer format (but handles e.g. 1e6, too). */
- if (dig <= 20 && ex10 == 0) {
- uint8_t *xis;
- uint64_t x = xi[0];
- double n;
- for (xis = xi+1; xis < xip; xis++) x = x * 100 + *xis;
- if (!(dig == 20 && (xi[0] > 18 || (int64_t)x >= 0))) { /* No overflow? */
- /* Format-specific handling. */
- switch (fmt) {
- case STRSCAN_INT:
- if (!(opt & STRSCAN_OPT_TONUM) && x < 0x80000000u+neg) {
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_INT; /* Fast path for 32 bit integers. */
- }
- if (!(opt & STRSCAN_OPT_C)) { fmt = STRSCAN_NUM; goto plainnumber; }
- /* fallthrough */
- case STRSCAN_U32:
- if ((x >> 32) != 0) return STRSCAN_ERROR;
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_U32;
- case STRSCAN_I64:
- case STRSCAN_U64:
- o->u64 = neg ? (uint64_t)-(int64_t)x : x;
- return fmt;
- default:
- plainnumber: /* Fast path for plain numbers < 2^63. */
- if ((int64_t)x < 0) break;
- n = (double)(int64_t)x;
- if (neg) n = -n;
- o->n = n;
- return fmt;
- }
- }
- }
-
- /* Slow non-integer path. */
- if (fmt == STRSCAN_INT) {
- if ((opt & STRSCAN_OPT_C)) return STRSCAN_ERROR;
- fmt = STRSCAN_NUM;
- } else if (fmt > STRSCAN_INT) {
- return STRSCAN_ERROR;
- }
- {
- uint32_t hi = 0, lo = (uint32_t)(xip-xi);
- int32_t ex2 = 0, idig = (int32_t)lo + (ex10 >> 1);
-
- lj_assertX(lo > 0 && (ex10 & 1) == 0, "bad lo %d ex10 %d", lo, ex10);
-
- /* Handle simple overflow/underflow. */
- if (idig > 310/2) { if (neg) setminfV(o); else setpinfV(o); return fmt; }
- else if (idig < -326/2) { o->n = neg ? -0.0 : 0.0; return fmt; }
-
- /* Scale up until we have at least 17 or 18 integer part digits. */
- while (idig < 9 && idig < DLEN(lo, hi)) {
- uint32_t i, cy = 0;
- ex2 -= 6;
- for (i = DPREV(lo); ; i = DPREV(i)) {
- uint32_t d = (xi[i] << 6) + cy;
- cy = (((d >> 2) * 5243) >> 17); d = d - cy * 100; /* Div/mod 100. */
- xi[i] = (uint8_t)d;
- if (i == hi) break;
- if (d == 0 && i == DPREV(lo)) lo = i;
- }
- if (cy) {
- hi = DPREV(hi);
- if (xi[DPREV(lo)] == 0) lo = DPREV(lo);
- else if (hi == lo) { lo = DPREV(lo); xi[DPREV(lo)] |= xi[lo]; }
- xi[hi] = (uint8_t)cy; idig++;
- }
- }
-
- /* Scale down until no more than 17 or 18 integer part digits remain. */
- while (idig > 9) {
- uint32_t i = hi, cy = 0;
- ex2 += 6;
- do {
- cy += xi[i];
- xi[i] = (cy >> 6);
- cy = 100 * (cy & 0x3f);
- if (xi[i] == 0 && i == hi) hi = DNEXT(hi), idig--;
- i = DNEXT(i);
- } while (i != lo);
- while (cy) {
- if (hi == lo) { xi[DPREV(lo)] |= 1; break; }
- xi[lo] = (cy >> 6); lo = DNEXT(lo);
- cy = 100 * (cy & 0x3f);
- }
- }
-
- /* Collect integer part digits and convert to rescaled double. */
- {
- uint64_t x = xi[hi];
- uint32_t i;
- for (i = DNEXT(hi); --idig > 0 && i != lo; i = DNEXT(i))
- x = x * 100 + xi[i];
- if (i == lo) {
- while (--idig >= 0) x = x * 100;
- } else { /* Gather round bit from remaining digits. */
- x <<= 1; ex2--;
- do {
- if (xi[i]) { x |= 1; break; }
- i = DNEXT(i);
- } while (i != lo);
- }
- strscan_double(x, o, ex2, neg);
- }
- }
- return fmt;
-}
-
-/* Parse binary number. */
-static StrScanFmt strscan_bin(const uint8_t *p, TValue *o,
- StrScanFmt fmt, uint32_t opt,
- int32_t ex2, int32_t neg, uint32_t dig)
-{
- uint64_t x = 0;
- uint32_t i;
-
- if (ex2 || dig > 64) return STRSCAN_ERROR;
-
- /* Scan binary digits. */
- for (i = dig; i; i--, p++) {
- if ((*p & ~1) != '0') return STRSCAN_ERROR;
- x = (x << 1) | (*p & 1);
- }
-
- /* Format-specific handling. */
- switch (fmt) {
- case STRSCAN_INT:
- if (!(opt & STRSCAN_OPT_TONUM) && x < 0x80000000u+neg) {
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_INT; /* Fast path for 32 bit integers. */
- }
- if (!(opt & STRSCAN_OPT_C)) { fmt = STRSCAN_NUM; break; }
- /* fallthrough */
- case STRSCAN_U32:
- if (dig > 32) return STRSCAN_ERROR;
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_U32;
- case STRSCAN_I64:
- case STRSCAN_U64:
- o->u64 = neg ? (uint64_t)-(int64_t)x : x;
- return fmt;
- default:
- break;
- }
-
- /* Reduce range, then convert to double. */
- if ((x & U64x(c0000000,0000000))) { x = (x >> 2) | (x & 3); ex2 += 2; }
- strscan_double(x, o, ex2, neg);
- return fmt;
-}
-
-/* Scan string containing a number. Returns format. Returns value in o. */
-StrScanFmt lj_strscan_scan(const uint8_t *p, MSize len, TValue *o,
- uint32_t opt)
-{
- int32_t neg = 0;
- const uint8_t *pe = p + len;
-
- /* Remove leading space, parse sign and non-numbers. */
- if (LJ_UNLIKELY(!lj_char_isdigit(*p))) {
- while (lj_char_isspace(*p)) p++;
- if (*p == '+' || *p == '-') neg = (*p++ == '-');
- if (LJ_UNLIKELY(*p >= 'A')) { /* Parse "inf", "infinity" or "nan". */
- TValue tmp;
- setnanV(&tmp);
- if (casecmp(p[0],'i') && casecmp(p[1],'n') && casecmp(p[2],'f')) {
- if (neg) setminfV(&tmp); else setpinfV(&tmp);
- p += 3;
- if (casecmp(p[0],'i') && casecmp(p[1],'n') && casecmp(p[2],'i') &&
- casecmp(p[3],'t') && casecmp(p[4],'y')) p += 5;
- } else if (casecmp(p[0],'n') && casecmp(p[1],'a') && casecmp(p[2],'n')) {
- p += 3;
- }
- while (lj_char_isspace(*p)) p++;
- if (*p || p < pe) return STRSCAN_ERROR;
- o->u64 = tmp.u64;
- return STRSCAN_NUM;
- }
- }
-
- /* Parse regular number. */
- {
- StrScanFmt fmt = STRSCAN_INT;
- int cmask = LJ_CHAR_DIGIT;
- int base = (opt & STRSCAN_OPT_C) && *p == '0' ? 0 : 10;
- const uint8_t *sp, *dp = NULL;
- uint32_t dig = 0, hasdig = 0, x = 0;
- int32_t ex = 0;
-
- /* Determine base and skip leading zeros. */
- if (LJ_UNLIKELY(*p <= '0')) {
- if (*p == '0') {
- if (casecmp(p[1], 'x'))
- base = 16, cmask = LJ_CHAR_XDIGIT, p += 2;
- else if (casecmp(p[1], 'b'))
- base = 2, cmask = LJ_CHAR_DIGIT, p += 2;
- }
- for ( ; ; p++) {
- if (*p == '0') {
- hasdig = 1;
- } else if (*p == '.') {
- if (dp) return STRSCAN_ERROR;
- dp = p;
- } else {
- break;
- }
- }
- }
-
- /* Preliminary digit and decimal point scan. */
- for (sp = p; ; p++) {
- if (LJ_LIKELY(lj_char_isa(*p, cmask))) {
- x = x * 10 + (*p & 15); /* For fast path below. */
- dig++;
- } else if (*p == '.') {
- if (dp) return STRSCAN_ERROR;
- dp = p;
- } else {
- break;
- }
- }
- if (!(hasdig | dig)) return STRSCAN_ERROR;
-
- /* Handle decimal point. */
- if (dp) {
- if (base == 2) return STRSCAN_ERROR;
- fmt = STRSCAN_NUM;
- if (dig) {
- ex = (int32_t)(dp-(p-1)); dp = p-1;
- while (ex < 0 && *dp-- == '0') ex++, dig--; /* Skip trailing zeros. */
- if (ex <= -STRSCAN_MAXEXP) return STRSCAN_ERROR;
- if (base == 16) ex *= 4;
- }
- }
-
- /* Parse exponent. */
- if (base >= 10 && casecmp(*p, (uint32_t)(base == 16 ? 'p' : 'e'))) {
- uint32_t xx;
- int negx = 0;
- fmt = STRSCAN_NUM; p++;
- if (*p == '+' || *p == '-') negx = (*p++ == '-');
- if (!lj_char_isdigit(*p)) return STRSCAN_ERROR;
- xx = (*p++ & 15);
- while (lj_char_isdigit(*p)) {
- xx = xx * 10 + (*p & 15);
- if (xx >= STRSCAN_MAXEXP) return STRSCAN_ERROR;
- p++;
- }
- ex += negx ? -(int32_t)xx : (int32_t)xx;
- }
-
- /* Parse suffix. */
- if (*p) {
- /* I (IMAG), U (U32), LL (I64), ULL/LLU (U64), L (long), UL/LU (ulong). */
- /* NYI: f (float). Not needed until cp_number() handles non-integers. */
- if (casecmp(*p, 'i')) {
- if (!(opt & STRSCAN_OPT_IMAG)) return STRSCAN_ERROR;
- p++; fmt = STRSCAN_IMAG;
- } else if (fmt == STRSCAN_INT) {
- if (casecmp(*p, 'u')) p++, fmt = STRSCAN_U32;
- if (casecmp(*p, 'l')) {
- p++;
- if (casecmp(*p, 'l')) p++, fmt += STRSCAN_I64 - STRSCAN_INT;
- else if (!(opt & STRSCAN_OPT_C)) return STRSCAN_ERROR;
- else if (sizeof(long) == 8) fmt += STRSCAN_I64 - STRSCAN_INT;
- }
- if (casecmp(*p, 'u') && (fmt == STRSCAN_INT || fmt == STRSCAN_I64))
- p++, fmt += STRSCAN_U32 - STRSCAN_INT;
- if ((fmt == STRSCAN_U32 && !(opt & STRSCAN_OPT_C)) ||
- (fmt >= STRSCAN_I64 && !(opt & STRSCAN_OPT_LL)))
- return STRSCAN_ERROR;
- }
- while (lj_char_isspace(*p)) p++;
- if (*p) return STRSCAN_ERROR;
- }
- if (p < pe) return STRSCAN_ERROR;
-
- /* Fast path for decimal 32 bit integers. */
- if (fmt == STRSCAN_INT && base == 10 &&
- (dig < 10 || (dig == 10 && *sp <= '2' && x < 0x80000000u+neg))) {
- if ((opt & STRSCAN_OPT_TONUM)) {
- o->n = neg ? -(double)x : (double)x;
- return STRSCAN_NUM;
- } else if (x == 0 && neg) {
- o->n = -0.0;
- return STRSCAN_NUM;
- } else {
- o->i = neg ? -(int32_t)x : (int32_t)x;
- return STRSCAN_INT;
- }
- }
-
- /* Dispatch to base-specific parser. */
- if (base == 0 && !(fmt == STRSCAN_NUM || fmt == STRSCAN_IMAG))
- return strscan_oct(sp, o, fmt, neg, dig);
- if (base == 16)
- fmt = strscan_hex(sp, o, fmt, opt, ex, neg, dig);
- else if (base == 2)
- fmt = strscan_bin(sp, o, fmt, opt, ex, neg, dig);
- else
- fmt = strscan_dec(sp, o, fmt, opt, ex, neg, dig);
-
- /* Try to convert number to integer, if requested. */
- if (fmt == STRSCAN_NUM && (opt & STRSCAN_OPT_TOINT) && !tvismzero(o)) {
- double n = o->n;
- int32_t i = lj_num2int(n);
- if (n == (lua_Number)i) { o->i = i; return STRSCAN_INT; }
- }
- return fmt;
- }
-}
-
-int LJ_FASTCALL lj_strscan_num(GCstr *str, TValue *o)
-{
- StrScanFmt fmt = lj_strscan_scan((const uint8_t *)strdata(str), str->len, o,
- STRSCAN_OPT_TONUM);
- lj_assertX(fmt == STRSCAN_ERROR || fmt == STRSCAN_NUM, "bad scan format");
- return (fmt != STRSCAN_ERROR);
-}
-
-#if LJ_DUALNUM
-int LJ_FASTCALL lj_strscan_number(GCstr *str, TValue *o)
-{
- StrScanFmt fmt = lj_strscan_scan((const uint8_t *)strdata(str), str->len, o,
- STRSCAN_OPT_TOINT);
- lj_assertX(fmt == STRSCAN_ERROR || fmt == STRSCAN_NUM || fmt == STRSCAN_INT,
- "bad scan format");
- if (fmt == STRSCAN_INT) setitype(o, LJ_TISNUM);
- return (fmt != STRSCAN_ERROR);
-}
-#endif
-
-#undef DNEXT
-#undef DPREV
-#undef DLEN
-
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-09 14:29:55 +0000