Scarfski/tinygltf
1
0
Fork 0
mirror of https://github.com/syoyo/tinygltf.git synced 2026-06-08 03:03:50 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fix float32_mode integer parsing: preserve int64 precision for integer-only tokens

Browse Source 
Co-authored-by: syoyo <18676+syoyo@users.noreply.github.com>
Agent-Logs-Url: https://github.com/syoyo/tinygltf/sessions/a77fd614-00f3-49c1-bb4a-0498771cc63b
This commit is contained in:
copilot-swe-agent[bot]
2026-03-20 21:24:37 +00:00
parent c870bd5fd6
commit c9a9b1175a
2 changed files with 47 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
tinygltf_json.h
View File

@@ -422,9 +422,11 @@ static int cj_fast_flt_convert(uint64_t mantissa, int exp10, int neg, float *out
* Returns pointer past the last character consumed, or NULL on error.
*
* float32_mode: when non-zero, floating-point values are parsed at float
* (single) precision — fewer digits are significant, and the result is
* stored as (double)(float)value. This is faster but not JSON-conformant
* for high-precision doubles.
* (single) precision — only 9 significant digits are tracked for the
* fraction part, and the result is stored as (double)(float)value. This
* is faster but not JSON-conformant for high-precision doubles. Integer-
* only tokens (no '.'/'e') are always parsed at full int64 precision
* regardless of this flag.
*
* Uses Clinger's fast path (no strtod) for ~99% of JSON float values.
* Falls back to strtod only for extreme exponents or >19 significant digits. */
@@ -444,8 +446,12 @@ static const char *cj_parse_number(const char *p, const char *end,
int mantissa_overflow = 0; /* set if >19 significant digits */
int has_frac = 0, has_exp = 0;
/* Max significant digits we track: 19 for double, 9 for float32 */
int max_sig = float32_mode ? 9 : 19;
/* Max significant digits we track:
* Integer part: always 19, so integer-only tokens (no '.'/'e') are always
* accumulated fully and can be typed as int64 regardless of float32_mode.
* Fraction part: 9 in float32_mode (single precision), 19 otherwise. */
int max_sig_int = 19;
int max_sig_frac = float32_mode ? 9 : 19;
/* Integer part */
if (*p == '0') {
@@ -453,7 +459,7 @@ static const char *cj_parse_number(const char *p, const char *end,
} else if ((unsigned)(*p - '1') <= 8u) {
while (p < end && (unsigned)(*p - '0') <= 9u) {
unsigned d = (unsigned)(*p - '0');
if (ndigits < max_sig) {
if (ndigits < max_sig_int) {
mantissa = mantissa * 10 + d;
} else {
exp10++; /* excess digit: bump exponent instead */
@@ -474,7 +480,7 @@ static const char *cj_parse_number(const char *p, const char *end,
if (p >= end || (unsigned)(*p - '0') > 9u) return NULL;
while (p < end && (unsigned)(*p - '0') <= 9u) {
unsigned d = (unsigned)(*p - '0');
if (ndigits < max_sig) {
if (ndigits < max_sig_frac) {
mantissa = mantissa * 10 + d;
exp10--;
}