#11107 Improve performance of length on a UTF16String

JuliaLang · May 2, 2015 · 63be5dc · 63be5dc
1 parent 0dad086
commit 63be5dc
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Showing 2 changed files with 20 additions and 20 deletions.
diff --git a/src/support/utf8.c b/src/support/utf8.c
@@ -234,11 +234,11 @@ size_t u8_offset(const char *s, size_t charnum)
 
 /**
  * @brief Calculates number of characters in a UTF-8 string
- * 
- * @param[in] iStr UTF-8 encoded string
- * @param[in] iLen Length of the string in bytes
  *
- * @return number of logical characters
+ * @param[in] s UTF-8 encoded string
+ * @param[in] offset Length of the string (or substring) in bytes
+ *
+ * @return Number of logical characters (or codepoints)
  */
 size_t u8_charnum(const char *s, size_t offset)
 {
@@ -256,23 +256,23 @@ size_t u8_charnum(const char *s, size_t offset)
 
 /**
  * @brief Calculates number of characters in a UTF-16 string
- * 
+ *
  * @param[in] iStr UTF-16 encoded string
  * @param[in] iLen Length of the string in 16-bit words
  *
- * @return number of logical characters
+ * @return  number of logical characters (or codepoints)
  */
 DLLEXPORT size_t u16_charnum(const uint16_t *iStr, size_t iLen)
 {
- size_t logChar = 0; // # of logical characters
+ size_t logChar = 0; // # of logical characters
  if (iLen) {
- do {
-  // Simply don't count trailing surrogate characters
-  // Since we are not doing validation anyway, we can just
-  // assume this is a valid UTF-16 string
-  logChar += !is_surrogate_trail(*iStr);
-  iStr++;
- } while (--iLen);
+ do {
+  // Simply don't count trailing surrogate characters
+  // Since we are not doing validation anyway, we can just
+  // assume this is a valid UTF-16 string
+  logChar += !is_surrogate_trail(*iStr);
+  iStr++;
+ } while (--iLen);
  }
  return logChar;
 }

diff --git a/src/support/utf8.h b/src/support/utf8.h
@@ -33,21 +33,21 @@ DLLEXPORT size_t u8_offset(const char *str, size_t charnum);
 
 /**
  * @brief Calculates number of characters in UTF-8 encoded string
- * 
- * @param[in] iStr UTF-8 encoded string
+ *
+ * @param[in] iStr UTF-8 encoded string (or substring)
  * @param[in] iLen Length of string (or substring) in bytes
  *
- * @return Number of logical characters in string (or substring)
+ * @return Number of logical characters (or codepoints) in string (or substring)
  */
-DLLEXPORT size_t u8_charnum(const char *iStr, size_t iOffset);
+DLLEXPORT size_t u8_charnum(const char *iStr, size_t iLen);
 
 /**
  * @brief Calculates number of characters in UTF-16 encoded string
- * 
+ *
  * @param[in] iStr UTF-16 encoded string
  * @param[in] iLen Length of the string (or substring) in 16-bit words
  *
- * @return Number of logical characters in string (or substring)
+ * @return Number of logical characters (or codepoints) in string (or substring)
  */
 DLLEXPORT size_t u16_charnum(const uint16_t *iStr, size_t iLen);