1 files changed, 59 insertions, 0 deletions
diff --git a/libc-top-half/headers/private/printscan.h b/libc-top-half/headers/private/printscan.h
new file mode 100644
index 0000000..7c21f99
--- /dev/null
+++ b/libc-top-half/headers/private/printscan.h
@@ -0,0 +1,59 @@
+#if defined(__wasilibc_printscan_no_floating_point)
+
+#include <stdio.h>
+
+__attribute__((__cold__, __noreturn__))
+static void floating_point_not_supported(void) {
+    void abort(void) __attribute__((__noreturn__));
+    fputs("Support for floating-point formatting is currently disabled.\n"
+          "To enable it, " __wasilibc_printscan_floating_point_support_option ".\n", stderr);
+    abort();
+}
+
+#elif defined(__wasilibc_printscan_no_long_double)
+
+#include <stdio.h>
+
+typedef double long_double;
+#undef LDBL_TRUE_MIN
+#define LDBL_TRUE_MIN DBL_DENORM_MIN
+#undef LDBL_MIN
+#define LDBL_MIN DBL_MIN
+#undef LDBL_MAX
+#define LDBL_MAX DBL_MAX
+#undef LDBL_EPSILON
+#define LDBL_EPSILON DBL_EPSILON
+#undef LDBL_MANT_DIG
+#define LDBL_MANT_DIG DBL_MANT_DIG
+#undef LDBL_MIN_EXP
+#define LDBL_MIN_EXP DBL_MIN_EXP
+#undef LDBL_MAX_EXP
+#define LDBL_MAX_EXP DBL_MAX_EXP
+#undef LDBL_DIG
+#define LDBL_DIG DBL_DIG
+#undef LDBL_MIN_10_EXP
+#define LDBL_MIN_10_EXP DBL_MIN_10_EXP
+#undef LDBL_MAX_10_EXP
+#define LDBL_MAX_10_EXP DBL_MAX_10_EXP
+#undef frexpl
+#define frexpl(x, exp) frexp(x, exp)
+#undef copysignl
+#define copysignl(x, y) copysign(x, y)
+#undef fmodl
+#define fmodl(x, y) fmod(x, y)
+#undef scalbnl
+#define scalbnl(arg, exp) scalbn(arg, exp)
+__attribute__((__cold__, __noreturn__))
+static void long_double_not_supported(void) {
+    void abort(void) __attribute__((__noreturn__));
+    fputs("Support for formatting long double values is currently disabled.\n"
+          "To enable it, " __wasilibc_printscan_full_support_option ".\n", &__stderr_FILE);
+    abort();
+}
+
+#else
+
+// Full long double support.
+typedef long double long_double;
+
+#endif