Fix build on OpenBSD (#1162)

Wisdurm · web-flow · commit 70a72f72122f · 2026-03-17T21:24:00.000+01:00
* Replace DBL_DECIMAL_DIG with more portable C++ variant.
diff --git a/include/crow/json.h b/include/crow/json.h
@@ -1896,9 +1896,9 @@ namespace crow // NOTE: Already documented in "crow/app.h"
                             if (v.nt == num_type::Double_precision_floating_point)
                             {
 #ifdef _MSC_VER
-                                sprintf_s(outbuf, sizeof(outbuf), "%.*g", DBL_DECIMAL_DIG, v.num.d);
+                                sprintf_s(outbuf, sizeof(outbuf), "%.*g", std::numeric_limits<double>::max_digits10, v.num.d);
 #else
-                                snprintf(outbuf, sizeof(outbuf), "%.*g", DBL_DECIMAL_DIG, v.num.d);
+                                snprintf(outbuf, sizeof(outbuf), "%.*g", std::numeric_limits<double>::max_digits10, v.num.d);
 #endif
                             }
                             else

Original file line number	Diff line number	Diff line change
`@@ -1896,9 +1896,9 @@ namespace crow // NOTE: Already documented in "crow/app.h"`
`1896`	`1896`	`if (v.nt == num_type::Double_precision_floating_point)`
`1897`	`1897`	`{`
`1898`	`1898`	`#ifdef _MSC_VER`
`1899`		`- sprintf_s(outbuf, sizeof(outbuf), "%.*g", DBL_DECIMAL_DIG, v.num.d);`
	`1899`	`+ sprintf_s(outbuf, sizeof(outbuf), "%.*g", std::numeric_limits<double>::max_digits10, v.num.d);`
`1900`	`1900`	`#else`
`1901`		`- snprintf(outbuf, sizeof(outbuf), "%.*g", DBL_DECIMAL_DIG, v.num.d);`
	`1901`	`+ snprintf(outbuf, sizeof(outbuf), "%.*g", std::numeric_limits<double>::max_digits10, v.num.d);`
`1902`	`1902`	`#endif`
`1903`	`1903`	`}`
`1904`	`1904`	`else`