error ("Attempt to change byte length of a string");
/* We can't accept a change causing byte combining. */
- if ((idxval > 0 && !CHAR_HEAD_P (*str)
- && (prev_byte = string_char_to_byte (array, idxval - 1),
- (prev_byte + 1 < idxval_byte
- || (p[-1] >= 0x80 && p[-1] < 0xA0))))
- || (idxval < XSTRING (array)->size - 1
- && (*str >=0x80 && *str < 0xA0)
- && !CHAR_HEAD_P (p[actual_len])))
+ if (!ASCII_BYTE_P (*str)
+ && ((idxval > 0 && !CHAR_HEAD_P (*str)
+ && (prev_byte = string_char_to_byte (array, idxval - 1),
+ BYTES_BY_CHAR_HEAD (XSTRING (array)->data[prev_byte])
+ > idxval_byte - prev_byte))
+ || (idxval < XSTRING (array)->size - 1
+ && !CHAR_HEAD_P (p[actual_len])
+ && new_len < BYTES_BY_CHAR_HEAD (*str))))
error ("Attempt to change char length of a string");
while (new_len--)
*p++ = *str++;