/*
Copyright 2000 Helix Code Inc.
*/
/* words.c: low-level indexing ops */
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <unicode.h>
#include "ibex_internal.h"
static signed char utf8_trans[] = {
'A', 'A', 'A', 'A', 'A', 'A', -1, 'C', 'E', 'E', 'E', 'E', 'I', 'I',
'I', 'I', -2, 'N', 'O', 'O', 'O', 'O', 'O', '*', 'O', 'U', 'U', 'U',
'U', 'Y', -3, -4, 'a', 'a', 'a', 'a', 'a', 'a', -5, 'c', 'e', 'e',
'e', 'e', 'i', 'i', 'i', 'i', -6, 'n', 'o', 'o', 'o', 'o', 'o', '/',
'o', 'u', 'u', 'u', 'u', 'y', -7, 'y', 'A', 'a', 'A', 'a', 'A', 'a',
'C', 'c', 'C', 'c', 'C', 'c', 'C', 'c', 'D', 'd', 'D', 'd', 'E', 'e',
'E', 'e', 'E', 'e', 'E', 'e', 'E', 'e', 'G', 'g', 'G', 'g', 'G', 'g',
'G', 'g', 'H', 'h', 'H', 'h', 'I', 'i', 'I', 'i', 'I', 'i', 'I', 'i',
'I', 'i', -8, -9, 'J', 'j', 'K', 'k', 'k', 'L', 'l', 'L', 'l', 'L',
'l', 'L', 'l', 'L', 'l', 'N', 'n', 'N', 'n', 'N', 'n', 'n', -10, -11,
'O', 'o', 'O', 'o', 'O', 'o', -12, -13, 'R', 'r', 'R', 'r', 'R', 'r',
'S', 'r', 'S', 's', 'S', 's', 'S', 's', 'T', 't', 'T', 't', 'T', 't',
'U', 'u', 'U', 'u', 'U', 'u', 'U', 'u', 'U', 'u', 'U', 'u', 'W', 'w',
'Y', 'y', 'Y', 'Z', 'z', 'Z', 'z', 'Z', 'z', 's'
};
static char *utf8_long_trans[] = {
"AE", "TH", "TH", "ss", "ae", "th", "th", "IJ", "ij", "NG", "ng", "OE", "oe"
};
/* This is a bit weird. It takes pointers to the start and end (actually
* just past the end) of a UTF-8-encoded word, and a buffer at least 1
* byte longer than the length of the word. It copies the word into the
* buffer in all lowercase without accents, and splits up ligatures.
* (Since any ligature would be a multi-byte character in UTF-8, splitting
* them into two US-ASCII characters won't overrun the buffer.)
*
* It is not safe to call this routine with bad UTF-8.
*/
static void
normalize_word(char *start, char *end, char *buf)
{
unsigned char *s, *d;
unicode_char_t uc;
s = (unsigned char *)start;
d = (unsigned char *)buf;
while (s < (unsigned char *)end)
{
if (*s < 0x80)
{
/* US-ASCII character: copy unless it's an apostrophe. */
if (*s != '\'')
*d++ = tolower(*s);
s++;
}
else
{
char *next = unicode_get_utf8(s, &uc);
if (uc >= 0xc0 && uc < 0xc0 + sizeof(utf8_trans))
{
signed char ch = utf8_trans[uc - 0xc0];
if (ch > 0)
*d++ = tolower(ch);
else
{
*d++ = tolower(utf8_long_trans[-ch - 1][0]);
*d++ = tolower(utf8_long_trans[-ch - 1][1]);
}
s = next;
}
else
{
while (s < (unsigned char *)next)
*d++ = *s++;
}
}
}
*d = '\0';
}
enum { IBEX_ALPHA, IBEX_NONALPHA, IBEX_INVALID, IBEX_INCOMPLETE };
/* This incorporates parts of libunicode, because there's no way to
* force libunicode to not read past a certain point.
*/
static int
utf8_category(char *sp, char **snp, char *send)
{
unsigned char *p = (unsigned char *)sp, **np = (unsigned char **)snp;
unsigned char *end = (unsigned char *)send;
if (isascii(*p))
{
*np = p + 1;
if (isalpha(*p) || *p == '\'')
return IBEX_ALPHA;
return IBEX_NONALPHA;
}
else
{
unicode_char_t uc;
int more;
if ((*p & 0xe0) == 0xc0)
{
more = 1;
uc = *p & 0x1f;
}
else if ((*p & 0xf0) == 0xe0)
{
more = 2;
uc = *p & 0x0f;
}
else if ((*p & 0xf8) == 0xf0)
{
more = 3;
uc = *p & 0x07;
}
else if ((*p & 0xfc) == 0xf8)
{
more = 4;
uc = *p & 0x03;
}
else if ((*p & 0xfe) == 0xfc)
{
more = 5;
uc = *p & 0x01;
}
else
return IBEX_INVALID;
if (p + more > end)
return IBEX_INCOMPLETE;
while (more--)
{
if ((*++p & 0xc0) != 0x80)
return IBEX_INVALID;
uc <<= 6;
uc |= *p & 0x3f;
}
*np = p + 1;
if (unicode_isalpha(uc))
return IBEX_ALPHA;
else
return IBEX_NONALPHA;
}
}
static ibex_file *
get_ibex_file(ibex *ib, char *name)
{
ibex_file *ibf;
ibf = g_tree_lookup(ib->files, name);
if (!ibf)
{
ibf = g_malloc(sizeof(ibex_file));
ibf->name = strdup(name);
ibf->index = 0;
g_tree_insert(ib->files, ibf->name, ibf);
ib->dirty = TRUE;
}
return ibf;
}
static void
ref_word(ibex *ib, ibex_file *ibf, char *word)
{
GPtrArray *refs;
refs = g_hash_table_lookup(ib->words, word);
if (!refs)
{
refs = g_ptr_array_new();
g_hash_table_insert(ib->words, g_strdup(word), refs);
g_ptr_array_add(refs, ibf);
ib->dirty = TRUE;
}
else if (g_ptr_array_index(refs, refs->len - 1) != ibf)
{
g_ptr_array_add(refs, ibf);
ib->dirty = TRUE;
}
}
int
ibex_index_buffer(ibex *ib, char *name, char *buffer,
size_t len, size_t *unread)
{
char *p, *q, *nq, *end, *word;
ibex_file *ibf = get_ibex_file(ib, name);
int wordsiz, cat;
end = buffer + len;
wordsiz = 20;
word = g_malloc(wordsiz);
p = buffer;
while (p < end)
{
while (p < end)
{
cat = utf8_category(p, &q, end);
if (cat != IBEX_NONALPHA)
break;
p = q;
}
if (p == end)
{
g_free(word);
return 0;
}
else if (cat == IBEX_INVALID)
{
errno = EINVAL;
g_free(word);
return -1;
}
else if (cat == IBEX_INCOMPLETE)
q = end;
while (q < end)
{
cat = utf8_category(q, &nq, end);
if (cat != IBEX_ALPHA)
break;
q = nq;
}
if (cat == IBEX_INVALID || (cat == IBEX_INCOMPLETE && !unread))
{
errno = EINVAL;
g_free(word);
return -1;
}
else if (cat == IBEX_INCOMPLETE || (q == end && unread))
{
*unread = end - p;
g_free(word);
return 0;
}
if (wordsiz < q - p + 1)
{
wordsiz = q - p + 1;
word = g_realloc(word, wordsiz);
}
normalize_word(p, q, word);
ref_word(ib, ibf, word);
p = q;
}
if (unread)
*unread = 0;
g_free(word);
return 0;
}
