xnu-792.6.76.tar.gz

[apple/xnu.git] / bsd / vfs / vfs_utfconv.c

diff --git a/bsd/vfs/vfs_utfconv.c b/bsd/vfs/vfs_utfconv.c
index 01a49889e3b5aab73923cac07eee2c2c836daaac..11af9238adae8f323eb71baaeaac955a8d327f25 100644 (file)
--- a/bsd/vfs/vfs_utfconv.c
+++ b/bsd/vfs/vfs_utfconv.c
@@ -117,10 +117,31 @@ unicode_decomposeable(u_int16_t character) {
        return (0);
 }
 
+
+/*
+ * Get the combing class.
+ *
+ * Similar to CFUniCharGetCombiningPropertyForCharacter.
+ */
+static inline u_int8_t
+get_combining_class(u_int16_t character) {
+       const u_int8_t *bitmap = __CFUniCharCombiningPropertyBitmap;
+
+       u_int8_t value = bitmap[(character >> 8)];
+
+       if (value) {
+               bitmap = bitmap + (value * 256);
+               return bitmap[character % 256];
+       }
+       return (0);
+}
+
+
 static int unicode_decompose(u_int16_t character, u_int16_t *convertedChars);
 
 static u_int16_t unicode_combine(u_int16_t base, u_int16_t combining);
 
+static void priortysort(u_int16_t* characters, int count);
 
 char utf_extrabytes[32] = {
         0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
@@ -316,6 +337,7 @@ utf8_decodestr(const u_int8_t* utf8p, size_t utf8len, u_int16_t* ucsp,
        u_int16_t* bufend;
        unsigned int ucs_ch;
        unsigned int byte;
+       int combcharcnt = 0;
        int result = 0;
        int decompose, precompose, swapbytes;
 
@@ -416,6 +438,7 @@ utf8_decodestr(const u_int8_t* utf8p, size_t utf8len, u_int16_t* ucsp,
                                                if (ucsp >= bufend)
                                                        goto toolong;
                                        }
+                                       combcharcnt += count - 1;
                                        continue;                       
                                }
                        } else if (precompose && (ucsp != bufstart)) {
@@ -436,8 +459,25 @@ utf8_decodestr(const u_int8_t* utf8p, size_t utf8len, u_int16_t* ucsp,
                if (ucs_ch == altslash)
                        ucs_ch = '/';
 
+               /*
+                * Make multiple combining character sequences canonical
+                */
+               if (unicode_combinable(ucs_ch)) {
+                       ++combcharcnt;   /* start tracking a run */
+               } else if (combcharcnt) {
+                       if (combcharcnt > 1) {
+                               priortysort(ucsp - combcharcnt, combcharcnt);
+                       }
+                       combcharcnt = 0;  /* start over */
+               }
                *ucsp++ = swapbytes ? NXSwapShort(ucs_ch) : ucs_ch;
        }
+       /*
+        * Make a previous combining sequence canonical
+        */
+       if (combcharcnt > 1) {
+               priortysort(ucsp - combcharcnt, combcharcnt);
+       }
 
 exit:
        *ucslen = (u_int8_t*)ucsp - (u_int8_t*)bufstart;
@@ -729,3 +769,39 @@ unicode_combine(u_int16_t base, u_int16_t combining)
        return (value);
 }
 
+
+/*
+ * priortysort - order combining chars into canonical order
+ *
+ * Similar to CFUniCharPrioritySort
+ */
+static void
+priortysort(u_int16_t* characters, int count)
+{
+       u_int32_t p1, p2;
+       u_int16_t *ch1, *ch2;
+       u_int16_t *end;
+       int changes = 1;
+
+       end = characters + count;
+       do {
+               changes = 0;
+               ch1 = characters;
+               ch2 = characters + 1;
+               p2 = get_combining_class(*ch1);
+               while (ch2 < end) {
+                       p1 = p2;
+                       p2 = get_combining_class(*ch2);
+                       if (p1 > p2) {
+                               u_int32_t tmp;
+
+                               tmp = *ch1;
+                               *ch1 = *ch2;
+                               *ch2 = tmp;
+                               changes = 1;
+                       }
+                       ++ch1;
+                       ++ch2;
+               }
+       } while (changes);
+}