char *strstr_m(const char *src, const char *findstr);
void strlower_m(char *s);
void strupper_m(char *s);
+size_t strlen_m_ext(const char *s, const charset_t dst_charset);
size_t strlen_m(const char *s);
size_t strlen_m_term(const char *s);
size_t strlen_m_term_null(const char *s);
}
/**
- Count the number of UCS2 characters in a string. Normally this will
- be the same as the number of bytes in a string for single byte strings,
- but will be different for multibyte.
-**/
-
-size_t strlen_m(const char *s)
+ * Calculate the number of units (8 or 16-bit, depending on the
+ * destination charset), that would be needed to convert the input
+ * string which is expected to be in in CH_UNIX encoding to the
+ * destination charset (which should be a unicode charset).
+ */
+size_t strlen_m_ext(const char *s, const charset_t dst_charset)
{
size_t count = 0;
while (*s) {
size_t c_size;
codepoint_t c = next_codepoint(s, &c_size);
- if (c < 0x10000) {
- /* Unicode char fits into 16 bits. */
+ s += c_size;
+
+ switch(dst_charset) {
+ case CH_UTF16LE:
+ case CH_UTF16BE:
+ case CH_UTF16MUNGED:
+ if (c < 0x10000) {
+ /* Unicode char fits into 16 bits. */
+ count += 1;
+ } else {
+ /* Double-width unicode char - 32 bits. */
+ count += 2;
+ }
+ break;
+ case CH_UTF8:
+ /*
+ * this only checks ranges, and does not
+ * check for invalid codepoints
+ */
+ if (c < 0x80) {
+ count += 1;
+ } else if (c < 0x800) {
+ count += 2;
+ } else if (c < 0x1000) {
+ count += 3;
+ } else {
+ count += 4;
+ }
+ break;
+ default:
+ /*
+ * non-unicode encoding:
+ * assume that each codepoint fits into
+ * one unit in the destination encoding.
+ */
count += 1;
- } else {
- /* Double-width unicode char - 32 bits. */
- count += 2;
}
- s += c_size;
}
return count;
}
+/**
+ Count the number of UCS2 characters in a string. Normally this will
+ be the same as the number of bytes in a string for single byte strings,
+ but will be different for multibyte.
+**/
+
+size_t strlen_m(const char *s)
+{
+ return strlen_m_ext(s, CH_UTF16LE);
+}
+
/**
Count the number of UCS2 characters in a string including the null
terminator.