freebsd-dev/contrib/less/charset.c
Xin LI a15691bf11 MFV r293125: less v481.
MFC after:	1 month
Relnotes:	yes
2016-01-05 05:25:16 +00:00

824 lines
16 KiB
C

/*
* Copyright (C) 1984-2015 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, 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>
#include <langinfo.h>
#endif
#include "charset.h"
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" },
{ "utf-8", &utf_mode, "8bcccbcc18b95.b126.bb" },
{ "iso8859", NULL, "8bcccbcc18b95.33b." },
{ "latin3", NULL, "8bcccbcc18b95.33b5.b8.b15.b4.b12.b18.b12.b." },
{ "arabic", NULL, "8bcccbcc18b95.33b.3b.7b2.13b.3b.b26.5b19.b" },
{ "greek", NULL, "8bcccbcc18b95.33b4.2b4.b3.b35.b44.b" },
{ "greek2005", NULL, "8bcccbcc18b95.33b14.b35.b44.b" },
{ "hebrew", NULL, "8bcccbcc18b95.33b.b29.32b28.2b2.b" },
{ "koi8-r", NULL, "8bcccbcc18b95.b." },
{ "KOI8-T", NULL, "8bcccbcc18b95.b8.b6.b8.b.b.5b7.3b4.b4.b3.b.b.3b." },
{ "georgianps", NULL, "8bcccbcc18b95.3b11.4b12.2b." },
{ "tcvn", NULL, "b..b...bcccbccbbb7.8b95.b48.5b." },
{ "TIS-620", NULL, "8bcccbcc18b95.b.4b.11b7.8b." },
{ "next", NULL, "8bcccbcc18b95.bb125.bb" },
{ "dos", NULL, "8bcccbcc12bc5b95.b." },
{ "windows-1251", NULL, "8bcccbcc12bc5b95.b24.b." },
{ "windows-1252", NULL, "8bcccbcc12bc5b95.b.b11.b.2b12.b." },
{ "windows-1255", NULL, "8bcccbcc12bc5b95.b.b8.b.5b9.b.4b." },
{ "ebcdic", NULL, "5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b." },
{ "IBM-1047", NULL, "4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc191.b" },
{ NULL, NULL, NULL }
};
/*
* Support "locale charmap"/nl_langinfo(CODESET) values, as well as others.
*/
struct cs_alias {
char *name;
char *oname;
} cs_aliases[] = {
{ "UTF-8", "utf-8" },
{ "ANSI_X3.4-1968", "ascii" },
{ "US-ASCII", "ascii" },
{ "latin1", "iso8859" },
{ "ISO-8859-1", "iso8859" },
{ "latin9", "iso8859" },
{ "ISO-8859-15", "iso8859" },
{ "latin2", "iso8859" },
{ "ISO-8859-2", "iso8859" },
{ "ISO-8859-3", "latin3" },
{ "latin4", "iso8859" },
{ "ISO-8859-4", "iso8859" },
{ "cyrillic", "iso8859" },
{ "ISO-8859-5", "iso8859" },
{ "ISO-8859-6", "arabic" },
{ "ISO-8859-7", "greek" },
{ "IBM9005", "greek2005" },
{ "ISO-8859-8", "hebrew" },
{ "latin5", "iso8859" },
{ "ISO-8859-9", "iso8859" },
{ "latin6", "iso8859" },
{ "ISO-8859-10", "iso8859" },
{ "latin7", "iso8859" },
{ "ISO-8859-13", "iso8859" },
{ "latin8", "iso8859" },
{ "ISO-8859-14", "iso8859" },
{ "latin10", "iso8859" },
{ "ISO-8859-16", "iso8859" },
{ "IBM437", "dos" },
{ "EBCDIC-US", "ebcdic" },
{ "IBM1047", "IBM-1047" },
{ "KOI8-R", "koi8-r" },
{ "KOI8-U", "koi8-r" },
{ "GEORGIAN-PS", "georgianps" },
{ "TCVN5712-1", "tcvn" },
{ "NEXTSTEP", "next" },
{ "windows", "windows-1252" }, /* backward compatibility */
{ "CP1251", "windows-1251" },
{ "CP1252", "windows-1252" },
{ "CP1255", "windows-1255" },
{ NULL, NULL }
};
#define IS_BINARY_CHAR 01
#define IS_CONTROL_CHAR 02
static char chardef[256];
static char *binfmt = NULL;
static char *utfbinfmt = 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, no_error)
register char *name;
int no_error;
{
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);
}
}
if (!no_error) {
error("invalid charset name", NULL_PARG);
quit(QUIT_ERROR);
}
return (0);
}
#if HAVE_LOCALE
/*
* Define a charset, given a locale name.
*/
static void
ilocale()
{
register int c;
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 (or binary utf) chars.
*/
static void
setbinfmt(s, fmtvarptr, default_fmt)
char *s;
char **fmtvarptr;
char *default_fmt;
{
if (s && utf_mode)
{
/* It would be too hard to account for width otherwise. */
char *t = s;
while (*t)
{
if (*t < ' ' || *t > '~')
{
s = default_fmt;
goto attr;
}
t++;
}
}
/* %n is evil */
if (s == NULL || *s == '\0' ||
(*s == '*' && (s[1] == '\0' || s[2] == '\0' || strchr(s + 2, 'n'))) ||
(*s != '*' && strchr(s, 'n')))
s = default_fmt;
/*
* Select the attributes if it starts with "*".
*/
attr:
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;
}
*fmtvarptr = s;
}
/*
*
*/
static void
set_charset()
{
char *s;
/*
* See if environment variable LESSCHARSET is defined.
*/
s = lgetenv("LESSCHARSET");
if (icharset(s, 0))
return;
/*
* LESSCHARSET is not defined: try LESSCHARDEF.
*/
s = lgetenv("LESSCHARDEF");
if (s != NULL && *s != '\0')
{
ichardef(s);
return;
}
#if HAVE_LOCALE
#ifdef CODESET
/*
* Try using the codeset name as the charset name.
*/
s = nl_langinfo(CODESET);
if (icharset(s, 1))
return;
#endif
#endif
#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
|| strstr(s, "UTF8") != NULL || strstr(s, "utf8") != NULL)
if (icharset("utf-8", 1))
return;
}
#endif
#if HAVE_LOCALE
/*
* Get character definitions from locale functions,
* rather than from predefined charset entry.
*/
ilocale();
#if MSDOS_COMPILER
/*
* Default to "dos".
*/
(void) icharset("dos", 1);
#else
/*
* Default to "latin1".
*/
(void) icharset("latin1", 1);
#endif
#endif
}
/*
* Initialize charset data structures.
*/
public void
init_charset()
{
char *s;
#if HAVE_LOCALE
setlocale(LC_ALL, "");
#endif
set_charset();
s = lgetenv("LESSBINFMT");
setbinfmt(s, &binfmt, "*s<%02X>");
s = lgetenv("LESSUTFBINFMT");
setbinfmt(s, &utfbinfmt, "<U+%04lX>");
}
/*
* Is a given character a "binary" character?
*/
public int
binary_char(c)
LWCHAR c;
{
if (utf_mode)
return (is_ubin_char(c));
c &= 0377;
return (chardef[c] & IS_BINARY_CHAR);
}
/*
* Is a given character a "control" character?
*/
public int
control_char(c)
LWCHAR 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)
LWCHAR c;
{
/* {{ This buffer can be overrun if LESSBINFMT is a long string. }} */
static char buf[32];
c &= 0377;
if ((c < 128 || !utf_mode) && !control_char(c))
SNPRINTF1(buf, sizeof(buf), "%c", (int) c);
else if (c == ESC)
strcpy(buf, "ESC");
#if IS_EBCDIC_HOST
else if (!binary_char(c) && c < 64)
SNPRINTF1(buf, sizeof(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))
SNPRINTF1(buf, sizeof(buf), "^%c", (int) (c ^ 0100));
#endif
else
SNPRINTF1(buf, sizeof(buf), binfmt, c);
return (buf);
}
/*
* Return the printable form of a UTF-8 character.
*/
public char *
prutfchar(ch)
LWCHAR ch;
{
static char buf[32];
if (ch == ESC)
strcpy(buf, "ESC");
else if (ch < 128 && control_char(ch))
{
if (!control_char(ch ^ 0100))
SNPRINTF1(buf, sizeof(buf), "^%c", ((char) ch) ^ 0100);
else
SNPRINTF1(buf, sizeof(buf), binfmt, (char) ch);
} else if (is_ubin_char(ch))
{
SNPRINTF1(buf, sizeof(buf), utfbinfmt, ch);
} else
{
char *p = buf;
if (ch >= 0x80000000)
ch = 0xFFFD; /* REPLACEMENT CHARACTER */
put_wchar(&p, ch);
*p = '\0';
}
return (buf);
}
/*
* Get the length of a UTF-8 character in bytes.
*/
public int
utf_len(ch)
char ch;
{
if ((ch & 0x80) == 0)
return 1;
if ((ch & 0xE0) == 0xC0)
return 2;
if ((ch & 0xF0) == 0xE0)
return 3;
if ((ch & 0xF8) == 0xF0)
return 4;
if ((ch & 0xFC) == 0xF8)
return 5;
if ((ch & 0xFE) == 0xFC)
return 6;
/* Invalid UTF-8 encoding. */
return 1;
}
/*
* Does the parameter point to the lead byte of a well-formed UTF-8 character?
*/
public int
is_utf8_well_formed(s, slen)
unsigned char *s;
int slen;
{
int i;
int len;
if (IS_UTF8_INVALID(s[0]))
return (0);
len = utf_len((char) s[0]);
if (len > slen)
return (0);
if (len == 1)
return (1);
if (len == 2)
{
if (s[0] < 0xC2)
return (0);
} else
{
unsigned char mask;
mask = (~((1 << (8-len)) - 1)) & 0xFF;
if (s[0] == mask && (s[1] & mask) == 0x80)
return (0);
}
for (i = 1; i < len; i++)
if (!IS_UTF8_TRAIL(s[i]))
return (0);
return (1);
}
/*
* Return number of invalid UTF-8 sequences found in a buffer.
*/
public int
utf_bin_count(data, len)
unsigned char *data;
int len;
{
int bin_count = 0;
while (len > 0)
{
if (is_utf8_well_formed(data, len))
{
int clen = utf_len(*data);
data += clen;
len -= clen;
} else
{
/* Skip to next lead byte. */
bin_count++;
do {
++data;
--len;
} while (len > 0 && !IS_UTF8_LEAD(*data));
}
}
return (bin_count);
}
/*
* Get the value of a UTF-8 character.
*/
public LWCHAR
get_wchar(p)
char *p;
{
switch (utf_len(p[0]))
{
case 1:
default:
/* 0xxxxxxx */
return (LWCHAR)
(p[0] & 0xFF);
case 2:
/* 110xxxxx 10xxxxxx */
return (LWCHAR) (
((p[0] & 0x1F) << 6) |
(p[1] & 0x3F));
case 3:
/* 1110xxxx 10xxxxxx 10xxxxxx */
return (LWCHAR) (
((p[0] & 0x0F) << 12) |
((p[1] & 0x3F) << 6) |
(p[2] & 0x3F));
case 4:
/* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
return (LWCHAR) (
((p[0] & 0x07) << 18) |
((p[1] & 0x3F) << 12) |
((p[2] & 0x3F) << 6) |
(p[3] & 0x3F));
case 5:
/* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
return (LWCHAR) (
((p[0] & 0x03) << 24) |
((p[1] & 0x3F) << 18) |
((p[2] & 0x3F) << 12) |
((p[3] & 0x3F) << 6) |
(p[4] & 0x3F));
case 6:
/* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
return (LWCHAR) (
((p[0] & 0x01) << 30) |
((p[1] & 0x3F) << 24) |
((p[2] & 0x3F) << 18) |
((p[3] & 0x3F) << 12) |
((p[4] & 0x3F) << 6) |
(p[5] & 0x3F));
}
}
/*
* Store a character into a UTF-8 string.
*/
public void
put_wchar(pp, ch)
char **pp;
LWCHAR ch;
{
if (!utf_mode || ch < 0x80)
{
/* 0xxxxxxx */
*(*pp)++ = (char) ch;
} else if (ch < 0x800)
{
/* 110xxxxx 10xxxxxx */
*(*pp)++ = (char) (0xC0 | ((ch >> 6) & 0x1F));
*(*pp)++ = (char) (0x80 | (ch & 0x3F));
} else if (ch < 0x10000)
{
/* 1110xxxx 10xxxxxx 10xxxxxx */
*(*pp)++ = (char) (0xE0 | ((ch >> 12) & 0x0F));
*(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
*(*pp)++ = (char) (0x80 | (ch & 0x3F));
} else if (ch < 0x200000)
{
/* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
*(*pp)++ = (char) (0xF0 | ((ch >> 18) & 0x07));
*(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F));
*(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
*(*pp)++ = (char) (0x80 | (ch & 0x3F));
} else if (ch < 0x4000000)
{
/* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
*(*pp)++ = (char) (0xF0 | ((ch >> 24) & 0x03));
*(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F));
*(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F));
*(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
*(*pp)++ = (char) (0x80 | (ch & 0x3F));
} else
{
/* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
*(*pp)++ = (char) (0xF0 | ((ch >> 30) & 0x01));
*(*pp)++ = (char) (0x80 | ((ch >> 24) & 0x3F));
*(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F));
*(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F));
*(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
*(*pp)++ = (char) (0x80 | (ch & 0x3F));
}
}
/*
* Step forward or backward one character in a string.
*/
public LWCHAR
step_char(pp, dir, limit)
char **pp;
signed int dir;
char *limit;
{
LWCHAR ch;
int len;
char *p = *pp;
if (!utf_mode)
{
/* It's easy if chars are one byte. */
if (dir > 0)
ch = (LWCHAR) ((p < limit) ? *p++ : 0);
else
ch = (LWCHAR) ((p > limit) ? *--p : 0);
} else if (dir > 0)
{
len = utf_len(*p);
if (p + len > limit)
{
ch = 0;
p = limit;
} else
{
ch = get_wchar(p);
p += len;
}
} else
{
while (p > limit && IS_UTF8_TRAIL(p[-1]))
p--;
if (p > limit)
ch = get_wchar(--p);
else
ch = 0;
}
*pp = p;
return ch;
}
/*
* Unicode characters data
* Actual data is in the generated *.uni files.
*/
#define DECLARE_RANGE_TABLE_START(name) \
static struct wchar_range name##_array[] = {
#define DECLARE_RANGE_TABLE_END(name) \
}; struct wchar_range_table name##_table = { name##_array, sizeof(name##_array)/sizeof(*name##_array) };
DECLARE_RANGE_TABLE_START(compose)
#include "compose.uni"
DECLARE_RANGE_TABLE_END(compose)
DECLARE_RANGE_TABLE_START(ubin)
#include "ubin.uni"
DECLARE_RANGE_TABLE_END(ubin)
DECLARE_RANGE_TABLE_START(wide)
#include "wide.uni"
DECLARE_RANGE_TABLE_END(wide)
/* comb_table is special pairs, not ranges. */
static struct wchar_range comb_table[] = {
{0x0644,0x0622}, {0x0644,0x0623}, {0x0644,0x0625}, {0x0644,0x0627},
};
static int
is_in_table(ch, table)
LWCHAR ch;
struct wchar_range_table *table;
{
int hi;
int lo;
/* Binary search in the table. */
if (ch < table->table[0].first)
return 0;
lo = 0;
hi = table->count - 1;
while (lo <= hi)
{
int mid = (lo + hi) / 2;
if (ch > table->table[mid].last)
lo = mid + 1;
else if (ch < table->table[mid].first)
hi = mid - 1;
else
return 1;
}
return 0;
}
/*
* Is a character a UTF-8 composing character?
* If a composing character follows any char, the two combine into one glyph.
*/
public int
is_composing_char(ch)
LWCHAR ch;
{
return is_in_table(ch, &compose_table);
}
/*
* Should this UTF-8 character be treated as binary?
*/
public int
is_ubin_char(ch)
LWCHAR ch;
{
return is_in_table(ch, &ubin_table);
}
/*
* Is this a double width UTF-8 character?
*/
public int
is_wide_char(ch)
LWCHAR ch;
{
return is_in_table(ch, &wide_table);
}
/*
* Is a character a UTF-8 combining character?
* A combining char acts like an ordinary char, but if it follows
* a specific char (not any char), the two combine into one glyph.
*/
public int
is_combining_char(ch1, ch2)
LWCHAR ch1;
LWCHAR ch2;
{
/* The table is small; use linear search. */
int i;
for (i = 0; i < sizeof(comb_table)/sizeof(*comb_table); i++)
{
if (ch1 == comb_table[i].first &&
ch2 == comb_table[i].last)
return 1;
}
return 0;
}