utf8.c: Use mnemonics instead of hex numbers

[perl5.git] / utf8.c

diff --git a/utf8.c b/utf8.c
index 2228778..2f4035b 100644 (file)
--- a/utf8.c
+++ b/utf8.c
@@ -1430,17 +1430,22 @@ Perl_utf16_to_utf8(pTHX_ U8* p, U8* d, I32 bytelen, I32 *newlen)
            *d++ = (U8)(( uv        & 0x3f) | 0x80);
            continue;
        }
-       if (uv >= 0xd800 && uv <= 0xdbff) {     /* surrogates */
+#define FIRST_HIGH_SURROGATE UNICODE_SURROGATE_FIRST
+#define LAST_HIGH_SURROGATE  0xDBFF
+#define FIRST_LOW_SURROGATE  0xDC00
+#define LAST_LOW_SURROGATE   UNICODE_SURROGATE_LAST
+       if (uv >= FIRST_HIGH_SURROGATE && uv <= LAST_HIGH_SURROGATE) {
            if (p >= pend) {
                Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
            } else {
                UV low = (p[0] << 8) + p[1];
                p += 2;
-               if (low < 0xdc00 || low > 0xdfff)
+               if (low < FIRST_LOW_SURROGATE || low > LAST_LOW_SURROGATE)
                    Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
-               uv = ((uv - 0xd800) << 10) + (low - 0xdc00) + 0x10000;
+               uv = ((uv - FIRST_HIGH_SURROGATE) << 10)
+                                       + (low - FIRST_LOW_SURROGATE) + 0x10000;
            }
-       } else if (uv >= 0xdc00 && uv <= 0xdfff) {
+       } else if (uv >= FIRST_LOW_SURROGATE && uv <= LAST_LOW_SURROGATE) {
            Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
        }
        if (uv < 0x10000) {