freebsd-src/contrib/less/charset.c
2002-01-07 20:29:38 +00:00

336 lines
6.1 KiB
C

/*
* Copyright (C) 1984-2000 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information about less, or for information on how to
* contact the author, see the README file.
*/
/*
* Functions to define the character set
* and do things specific to the character set.
*/
#include "less.h"
#if HAVE_LOCALE
#include <locale.h>
#include <ctype.h>
#endif
public int utf_mode = 0;
/*
* Predefined character sets,
* selected by the LESSCHARSET environment variable.
*/
struct charset {
char *name;
int *p_flag;
char *desc;
} charsets[] = {
{ "ascii", NULL, "8bcccbcc18b95.b" },
{ "dos", NULL, "8bcccbcc12bc5b223.b" },
{ "ebcdic", NULL, "5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b." },
{ "IBM-1047", NULL, "4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc191.b" },
{ "iso8859", NULL, "8bcccbcc18b95.33b." },
{ "koi8-r", NULL, "8bcccbcc18b95.b128." },
{ "next", NULL, "8bcccbcc18b95.bb125.bb" },
{ "utf-8", &utf_mode, "8bcccbcc18b." },
{ NULL, NULL, NULL }
};
struct cs_alias {
char *name;
char *oname;
} cs_aliases[] = {
{ "latin1", "iso8859" },
{ "latin9", "iso8859" },
{ NULL, NULL }
};
#define IS_BINARY_CHAR 01
#define IS_CONTROL_CHAR 02
static char chardef[256];
static char *binfmt = NULL;
public int binattr = AT_STANDOUT;
/*
* Define a charset, given a description string.
* The string consists of 256 letters,
* one for each character in the charset.
* If the string is shorter than 256 letters, missing letters
* are taken to be identical to the last one.
* A decimal number followed by a letter is taken to be a
* repetition of the letter.
*
* Each letter is one of:
* . normal character
* b binary character
* c control character
*/
static void
ichardef(s)
char *s;
{
register char *cp;
register int n;
register char v;
n = 0;
v = 0;
cp = chardef;
while (*s != '\0')
{
switch (*s++)
{
case '.':
v = 0;
break;
case 'c':
v = IS_CONTROL_CHAR;
break;
case 'b':
v = IS_BINARY_CHAR|IS_CONTROL_CHAR;
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
n = (10 * n) + (s[-1] - '0');
continue;
default:
error("invalid chardef", NULL_PARG);
quit(QUIT_ERROR);
/*NOTREACHED*/
}
do
{
if (cp >= chardef + sizeof(chardef))
{
error("chardef longer than 256", NULL_PARG);
quit(QUIT_ERROR);
/*NOTREACHED*/
}
*cp++ = v;
} while (--n > 0);
n = 0;
}
while (cp < chardef + sizeof(chardef))
*cp++ = v;
}
/*
* Define a charset, given a charset name.
* The valid charset names are listed in the "charsets" array.
*/
static int
icharset(name)
register char *name;
{
register struct charset *p;
register struct cs_alias *a;
if (name == NULL || *name == '\0')
return (0);
/* First see if the name is an alias. */
for (a = cs_aliases; a->name != NULL; a++)
{
if (strcmp(name, a->name) == 0)
{
name = a->oname;
break;
}
}
for (p = charsets; p->name != NULL; p++)
{
if (strcmp(name, p->name) == 0)
{
ichardef(p->desc);
if (p->p_flag != NULL)
*(p->p_flag) = 1;
return (1);
}
}
error("invalid charset name", NULL_PARG);
quit(QUIT_ERROR);
/*NOTREACHED*/
}
#if HAVE_LOCALE
/*
* Define a charset, given a locale name.
*/
static void
ilocale()
{
register int c;
setlocale(LC_ALL, "");
for (c = 0; c < (int) sizeof(chardef); c++)
{
if (isprint(c))
chardef[c] = 0;
else if (iscntrl(c))
chardef[c] = IS_CONTROL_CHAR;
else
chardef[c] = IS_BINARY_CHAR|IS_CONTROL_CHAR;
}
}
#endif
/*
* Define the printing format for control chars.
*/
public void
setbinfmt(s)
char *s;
{
if (s == NULL || *s == '\0')
s = "*s<%X>";
/*
* Select the attributes if it starts with "*".
*/
if (*s == '*')
{
switch (s[1])
{
case 'd': binattr = AT_BOLD; break;
case 'k': binattr = AT_BLINK; break;
case 's': binattr = AT_STANDOUT; break;
case 'u': binattr = AT_UNDERLINE; break;
default: binattr = AT_NORMAL; break;
}
s += 2;
}
binfmt = s;
}
/*
* Initialize charset data structures.
*/
public void
init_charset()
{
register char *s;
s = lgetenv("LESSBINFMT");
setbinfmt(s);
/*
* See if environment variable LESSCHARSET is defined.
*/
s = lgetenv("LESSCHARSET");
if (icharset(s))
return;
/*
* LESSCHARSET is not defined: try LESSCHARDEF.
*/
s = lgetenv("LESSCHARDEF");
if (s != NULL && *s != '\0')
{
ichardef(s);
return;
}
#if HAVE_STRSTR
/*
* Check whether LC_ALL, LC_CTYPE or LANG look like UTF-8 is used.
*/
if ((s = lgetenv("LC_ALL")) != NULL ||
(s = lgetenv("LC_CTYPE")) != NULL ||
(s = lgetenv("LANG")) != NULL)
{
if (strstr(s, "UTF-8") != NULL || strstr(s, "utf-8") != NULL)
if (icharset("utf-8"))
return;
}
#endif
#if HAVE_LOCALE
/*
* Use setlocale.
*/
ilocale();
#else
#if MSDOS_COMPILER
/*
* Default to "dos".
*/
(void) icharset("dos");
#else
/*
* Default to "latin1".
*/
(void) icharset("latin1");
#endif
#endif
}
/*
* Is a given character a "binary" character?
*/
public int
binary_char(c)
unsigned char c;
{
c &= 0377;
return (chardef[c] & IS_BINARY_CHAR);
}
/*
* Is a given character a "control" character?
*/
public int
control_char(c)
int c;
{
c &= 0377;
return (chardef[c] & IS_CONTROL_CHAR);
}
/*
* Return the printable form of a character.
* For example, in the "ascii" charset '\3' is printed as "^C".
*/
public char *
prchar(c)
int c;
{
static char buf[8];
c &= 0377;
if (!control_char(c))
sprintf(buf, "%c", c);
else if (c == ESC)
sprintf(buf, "ESC");
#if IS_EBCDIC_HOST
else if (!binary_char(c) && c < 64)
sprintf(buf, "^%c",
/*
* This array roughly inverts CONTROL() #defined in less.h,
* and should be kept in sync with CONTROL() and IBM-1047.
*/
"@ABC.I.?...KLMNO"
"PQRS.JH.XY.."
"\\]^_"
"......W[.....EFG"
"..V....D....TU.Z"[c]);
#else
else if (c < 128 && !control_char(c ^ 0100))
sprintf(buf, "^%c", c ^ 0100);
#endif
else
sprintf(buf, binfmt, c);
return (buf);
}