diff options
| -rw-r--r-- | src/charset.c | 77 |
1 files changed, 68 insertions, 9 deletions
diff --git a/src/charset.c b/src/charset.c index 7e605dada1b..905efee017a 100644 --- a/src/charset.c +++ b/src/charset.c @@ -92,6 +92,9 @@ int n_cmpchars; unsigned char *_fetch_multibyte_char_p; int _fetch_multibyte_char_len; +#define min(X, Y) ((X) < (Y) ? (X) : (Y)) +#define max(X, Y) ((X) > (Y) ? (X) : (Y)) + /* Set STR a pointer to the multi-byte form of the character C. If C is not a composite character, the multi-byte form is set in WORKBUF and STR points WORKBUF. The caller should allocate at least 4-byte @@ -831,9 +834,9 @@ strwidth (str, len) DEFUN ("string-width", Fstring_width, Sstring_width, 1, 1, 0, "Return width of STRING when displayed in the current buffer.\n\ Width is measured by how many columns it occupies on the screen.\n\ -When calculating width of a multi-byte character in STRING,\n\ - only the base leading-code is considered and the validity of\n\ - the following bytes are not checked.") +When calculating width of a multibyte character in STRING,\n\ +only the base leading-code is considered; the validity of\n\ +the following bytes is not checked.") (str) Lisp_Object str; { @@ -860,7 +863,11 @@ The returned value is 0 for left-to-right and 1 for right-to-left.") } DEFUN ("chars-in-string", Fchars_in_string, Schars_in_string, 1, 1, 0, - "Return number of characters in STRING.") + "Return number of characters in STRING.\n\ +When using multibyte characters, this is not the necessarily same as\n\ +the length of STRING; the length counts a multibyte characters as\n\ +several bytes, but this function counts a multibyte character as one\n\ +character.") (str) Lisp_Object str; { @@ -888,14 +895,65 @@ DEFUN ("chars-in-string", Fchars_in_string, Schars_in_string, 1, 1, 0, return val; } +DEFUN ("count-chars-region", Fcount_chars_region, Scount_chars_region, 2, 2, 0, + "Return number of characters between BEG and END.\n\ +When using multibyte characters, this is not the necessarily same as\n\ +(- END BEG); that subtraction gives you the number of bytes, which\n\ +may be more than the number of characters.") + (beg, end) + Lisp_Object beg, end; +{ + int from, to, stop; + Lisp_Object val; + int chars = 0; + unsigned char *p, *endp; + + validate_region (&beg, &end); + + from = min (XFASTINT (beg), XFASTINT (end)); + stop = to = max (XFASTINT (beg), XFASTINT (end)); + p = POS_ADDR (from); + endp = POS_ADDR (stop); + + if (from < GPT && GPT < to) + stop = GPT; + + while (1) + { + if (p == endp) + { + if (stop == GPT) + { + p = POS_ADDR (stop); + stop = to; + endp = POS_ADDR (stop); + } + else + break; + } + + if (*p == LEADING_CODE_COMPOSITION) + { + p++; + while (p < endp && ! CHAR_HEAD_P (p)) p++; + } + else + p += BYTES_BY_CHAR_HEAD (*p); + + chars++; + } + + return make_number (chars); +} + DEFUN ("char-boundary-p", Fchar_boundary_p, Schar_boundary_p, 1, 1, 0, "Return non-nil value if POS is at character boundary of multibyte form.\n\ -The return value is:\n\ +When the value is non-nil, it contains some additional information:\n\ 0 if POS is at an ASCII character or at the end of range,\n\ - 1 if POS is at a head of 2-byte length multi-byte form,\n\ - 2 if POS is at a head of 3-byte length multi-byte form,\n\ - 3 if POS is at a head of 4-byte length multi-byte form,\n\ - 4 if POS is at a head of multi-byte form of a composite character.\n\ + 1 if POS is before a 2-byte length multi-byte form,\n\ + 2 if POS is before a 3-byte length multi-byte form,\n\ + 3 if POS is before a 4-byte length multi-byte form,\n\ + 4 if POS is before a composite character.\n\ If POS is out of range or not at character boundary, return NIL.") (pos) Lisp_Object pos; @@ -1496,6 +1554,7 @@ syms_of_charset () defsubr (&Sstring_width); defsubr (&Schar_direction); defsubr (&Schars_in_string); + defsubr (&Scount_chars_region); defsubr (&Schar_boundary_p); defsubr (&Sconcat_chars); defsubr (&Scmpcharp); |