Centralize UTFN code point counting

Change-Id: Ifd6bdcb4ac88452ab01124777168b140cae965a9
Reviewed-on: https://skia-review.googlesource.com/128014
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Herb Derby <herb@google.com>

2 files changed, 24 insertions, 6 deletions

diff --git a/src/core/SkUtils.cpp b/src/core/SkUtils.cpp
index d8ba2b39c1..0b92510bb0 100644
--- a/src/core/SkUtils.cpp
+++ b/src/core/SkUtils.cpp
@@ -372,12 +372,6 @@ size_t SkUTF16_ToUTF8(const uint16_t utf16[], int numberOf16BitValues,
     return size;
 }
 
-const char SkHexadecimalDigits::gUpper[16] =
-           { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
-const char SkHexadecimalDigits::gLower[16] =
-           { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
-
-
 // returns -1 on error
 int SkUTF32_CountUnichars(const void* text, size_t byteLength) {
     if (byteLength == 0) {
@@ -398,3 +392,25 @@ int SkUTF32_CountUnichars(const void* text, size_t byteLength) {
     return SkToInt(byteLength >> 2);
 }
 
+// returns -1 on error
+int SkUTFN_CountUnichars(
+    SkTypeface::Encoding encoding, const void* utfN, size_t byteLength) {
+    SkASSERT(utfN != nullptr);
+    switch (encoding) {
+        case SkTypeface::kUTF8_Encoding:
+            return SkUTF8_CountUnichars(utfN, byteLength);
+        case SkTypeface::kUTF16_Encoding:
+            return SkUTF16_CountUnichars(utfN, byteLength);
+        case SkTypeface::kUTF32_Encoding:
+            return SkUTF32_CountUnichars(utfN, byteLength);
+        default:
+            SkDEBUGFAIL("unknown text encoding");
+    }
+
+    return -1;
+}
+
+const char SkHexadecimalDigits::gUpper[16] =
+    { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
+const char SkHexadecimalDigits::gLower[16] =
+    { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
\ No newline at end of file
diff --git a/src/core/SkUtils.h b/src/core/SkUtils.h
index 9d7c64524f..6037b60c3c 100644
--- a/src/core/SkUtils.h
+++ b/src/core/SkUtils.h
@@ -11,6 +11,7 @@
 #include "SkTypes.h"
 #include "SkMath.h"
 #include "SkOpts.h"
+#include "SkTypeface.h"
 
 /** Similar to memset(), but it assigns a 16, 32, or 64-bit value into the buffer.
     @param buffer   The memory to have value copied into it
@@ -47,6 +48,7 @@ int         SkUTF8_CountUnichars(const char utf8[]);
 int SkUTF8_CountUnichars(const void* utf8, size_t byteLength);
 int SkUTF16_CountUnichars(const void* utf16, size_t byteLength);
 int SkUTF32_CountUnichars(const void* utf32, size_t byteLength);
+int SkUTFN_CountUnichars(SkTypeface::Encoding encoding, const void* utfN, size_t byteLength);
 
 /** This function is safe: invalid UTF8 sequences will return -1
  *  When -1 is returned, ptr is unchanged.