Fixed utf8 tables again. Separate casefold, toupper, tolower functions.

1 files changed, 16 insertions, 3 deletions

diff --git a/src/utf8code.c b/src/utf8code.c
index 0cdcd8b6..38dff832 100644
--- a/src/utf8code.c
+++ b/src/utf8code.c
@@ -59,7 +59,7 @@ bool utf8_valid_n(const char* s, size_t n) {
     return d.state == 0;
 }
 
-uint32_t utf8_tolower(uint32_t c) {
+uint32_t utf8_casefold(uint32_t c) {
     for (size_t i=0; i < casefold_len; ++i) {
         const struct CaseMapping entry = casemappings[i];
         if (c <= entry.c1) {
@@ -72,9 +72,22 @@ uint32_t utf8_tolower(uint32_t c) {
     return c;
 }
 
-uint32_t utf8_toupper(uint32_t c) {
+uint32_t utf8_tolower(uint32_t c) {
     for (size_t i=0; i < sizeof upcase_ind/sizeof *upcase_ind; ++i) {
-        struct CaseMapping entry = casemappings[upcase_ind[i]];
+        const struct CaseMapping entry = casemappings[upcase_ind[i]];
+        if (c <= entry.c1) {
+            if (c < entry.c0) return c;
+            int d = entry.m1 - entry.c1;
+            if (d == 1) return c + ((entry.c1 & 1) == (c & 1));
+            return c + d;
+        }
+    }
+    return c;
+}
+
+uint32_t utf8_toupper(uint32_t c) {
+    for (size_t i=0; i < sizeof lowcase_ind/sizeof *lowcase_ind; ++i) {
+        const struct CaseMapping entry = casemappings[lowcase_ind[i]];
         if (c <= entry.m1) {
             int d = entry.m1 - entry.c1;
             if (c < (uint32_t)(entry.c0 + d)) return c;