** Merged from IBEX_DISK branch to head.

2000-09-19  Not Zed  <NotZed@HelixCode.com>

	** Merged from IBEX_DISK branch to head.

svn path=/trunk/; revision=5500

1 files changed, 512 insertions, 0 deletions

diff --git a/libibex/ibex_db.c b/libibex/ibex_db.c
new file mode 100644
index 0000000000..1ef0b3d1bc
--- /dev/null
+++ b/libibex/ibex_db.c
@@ -0,0 +1,512 @@
+
+#include <glib.h>
+
+#include <db.h>
+#include <stdio.h>
+#include <unicode.h>
+#include <ctype.h>
+
+#include "ibex_internal.h"
+
+#define d(x)
+
+/*
+  Uses 2 databases: 
+
+  names - HASH  - lists which files are stored
+  words - BTREE - index words to files
+
+*/
+
+static int
+db_delete_name(DB *db, const char *name)
+{
+	DBC *cursor;
+	int err, namelen;
+	DBT key, data;
+
+	printf("called to delete name %s\n", name);
+	return 0;
+
+	err = db->cursor(db, NULL, &cursor, 0);
+	if (err != 0) {
+		printf("Error occured?: %s\n", db_strerror(err));
+		return err;
+	}
+
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
+	namelen = strlen(name);
+
+	err = cursor->c_get(cursor, &key, &data, DB_FIRST);
+	while (err == 0) {
+		if (data.size == namelen && memcmp(data.data, name, namelen) == 0) {
+			d(printf("Found match, removing it\n"));
+			cursor->c_del(cursor, 0);
+		} else {
+			data.size = namelen;
+			data.data = (void *)name;
+			if (cursor->c_get(cursor, &key, &data, DB_GET_BOTH) == 0) {
+				d(printf("seek to match, removing it\n"));
+				cursor->c_del(cursor, 0);
+			} else {
+				d(printf("seek to match, not found\n"));
+			}
+		}
+		err = cursor->c_get(cursor, &key, &data, DB_NEXT_NODUP);
+	}
+
+	cursor->c_close(cursor);
+
+	return 0;
+}
+
+static int
+db_index_words(DB *db, char *name, char **words)
+{
+	DBT key, data;
+	int err = 0;
+	char *word;
+	
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
+	data.data = name;
+	data.size = strlen(name);
+	for (;(word=*words);words++) {
+		/* normalise word first ... */
+		key.data = word;
+		key.size = strlen(word);
+
+		err = db->put(db, NULL, &key, &data, 0);
+		if (err != 0)
+			printf("Error occured?: %s\n", db_strerror(err));
+	}
+
+	return err;
+}
+
+static int
+db_index_word(DB *db, char *name, char *word)
+{
+	DBT key, data;
+	int err = 0;
+	
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
+	data.data = name;
+	data.size = strlen(name);
+	key.data = word;
+	key.size = strlen(word);
+
+	err = db->put(db, NULL, &key, &data, 0);
+	if (err != 0)
+		printf("Error occured?: %s\n", db_strerror(err));
+
+	return err;
+}
+
+static GPtrArray *
+db_find(DB *db, char *word)
+{
+	DBT key, data;
+	int err;
+	DBC *cursor;
+	GPtrArray *matches = g_ptr_array_new();
+
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
+
+	err = db->cursor(db, NULL, &cursor, 0);
+	if (err != 0) {
+		printf("Error occured?: %s\n", db_strerror(err));
+		return matches;
+	}
+
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
+
+	key.size = strlen(word);
+	key.data = word;
+
+	err = cursor->c_get(cursor, &key, &data, DB_SET);
+	while (err == 0) {
+		char *name;
+		name = g_malloc(data.size+1);
+		memcpy(name, data.data, data.size);
+		name[data.size] = '\0';
+		g_ptr_array_add(matches, name);
+		err = cursor->c_get(cursor, &key, &data, DB_NEXT_DUP);
+	}
+	if (err != DB_NOTFOUND) {
+		printf("Error occured?: %s\n", db_strerror(err));
+		/* what to do?  doesn't matter too much its just a search ... */
+	}
+
+	cursor->c_close(cursor);
+
+	return matches;
+}
+
+/* check that db contains key @word, optionally with contents @name */
+static gboolean
+db_contains_word(DB *db, char *name, char *word)
+{
+	DBT key, data;
+
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
+
+	if (name != NULL) {
+		data.size = strlen(name);
+		data.data = name;
+	}
+	key.size = strlen(word);
+	key.data = word;
+
+	return db->get(db, NULL, &key, &data, name?DB_GET_BOTH:DB_SET) == 0;
+}
+
+static int
+db_delete_word(DB *db, char *word)
+{
+	DBT key;
+
+	memset(&key, 0, sizeof(key));
+	key.size = strlen(word);
+	key.data = word;
+	return db->del(db, NULL, &key, 0);
+}
+
+
+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
+ibex_normalise_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 void
+do_insert_words(char *key, char *name, ibex *ib)
+{
+	db_index_word(ib->words, name, key);
+	g_free(key);
+}
+
+static void
+do_free_words(char *key, char *name, void *data)
+{
+	g_free(key);
+}
+
+/**
+ * ibex_index_buffer: the lowest-level ibex indexing interface
+ * @ib: an ibex
+ * @name: the name of the file being indexed
+ * @buffer: a buffer containing data from the file
+ * @len: the length of @buffer
+ * @unread: an output argument containing the number of unread bytes
+ *
+ * This routine indexes up to @len bytes from @buffer into @ib.
+ * If @unread is NULL, the indexer assumes that the buffer ends on a
+ * word boundary, and will index all the way to the end of the
+ * buffer. If @unread is not NULL, and the buffer ends with an
+ * alphabetic character, the indexer will assume that the buffer has
+ * been cut off in the middle of a word, and return the number of
+ * un-indexed bytes at the end of the buffer in *@unread. The caller
+ * should then read in more data through whatever means it has
+ * and pass in the unread bytes from the original buffer, followed
+ * by the new data, on its next call.
+ *
+ * Return value: 0 on success, -1 on failure.
+ **/
+int
+ibex_index_buffer (ibex *ib, char *name, char *buffer, size_t len, size_t *unread)
+{
+	char *p, *q, *nq, *end, *word;
+	int wordsiz, cat;
+	GHashTable *words = g_hash_table_new(g_str_hash, g_str_equal);
+
+	if (unread)
+		*unread = 0;
+
+	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) {
+			goto done;
+		} else if (cat == IBEX_INVALID) {
+			goto error;
+		} 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)) {
+			goto error;
+		} else if (cat == IBEX_INCOMPLETE || (q == end && unread)) {
+			*unread = end - p;
+			goto done;
+		}
+
+		if (wordsiz < q - p + 1) {
+			wordsiz = q - p + 1;
+			word = g_realloc (word, wordsiz);
+		}
+		ibex_normalise_word (p, q, word);
+		if (word[0]) {
+			if (g_hash_table_lookup(words, word) == 0) {
+				g_hash_table_insert(words, g_strdup(word), name);
+			}
+		}
+		p = q;
+	}
+done:
+	/* FIXME: do this and inserts within a transaction */
+	if (!db_contains_word(ib->names, NULL, name)) {
+		printf("adding '%s' to database\n", name);
+		db_index_word(ib->names, "", name);
+	}
+	g_hash_table_foreach(words, (GHFunc)do_insert_words, ib);
+	g_hash_table_destroy(words);
+	g_free (word);
+	return 0;
+error:
+	g_hash_table_foreach(words, (GHFunc)do_free_words, NULL);
+	g_hash_table_destroy(words);
+	g_free (word);
+	return -1;
+}
+
+
+ibex *ibex_open (char *file, int flags, int mode)
+{
+	ibex *ib;
+	u_int32_t dbflags = 0;
+	int err;
+
+	ib = g_malloc0(sizeof(*ib));
+	err = db_create(&ib->words, NULL, 0);
+	if (err != 0) {
+		g_warning("create: Error occured?: %s\n", db_strerror(err));
+		g_free(ib);
+		return NULL;
+	}
+
+	err = ib->words->set_flags(ib->words, DB_DUP);
+	if (err != 0) {
+		g_warning("set flags: Error occured?: %s\n", db_strerror(err));
+		ib->words->close(ib->words, 0);
+		g_free(ib);
+		return NULL;
+	}
+
+	if (flags & O_CREAT)
+		dbflags |= DB_CREATE;
+	if (flags & O_EXCL)
+		dbflags |= DB_EXCL;
+	if (flags & O_RDONLY)
+		dbflags |= DB_RDONLY;
+
+	/* 1MB cache size? */
+	ib->words->set_cachesize(ib->words, 0, 1000000, 0);
+
+	err = ib->words->open(ib->words, file, "words", DB_BTREE, dbflags, mode);
+	if (err != 0) {
+		printf("open: Error occured?: %s\n", db_strerror(err));
+		ib->words->close(ib->words, 0);
+		g_free(ib);		
+		return NULL;
+	}
+
+	/* FIXME: check returns */
+	err = db_create(&ib->names, NULL, 0);
+	err = ib->names->open(ib->names, file, "names", DB_HASH, dbflags, mode);
+
+	return ib;
+}
+
+int ibex_save (ibex *ib)
+{
+	printf("syncing database\n");
+	ib->names->sync(ib->names, 0);
+	return ib->words->sync(ib->words, 0);
+}
+
+int ibex_close (ibex *ib)
+{
+	int ret;
+
+	printf("closing database\n");
+
+	ret = ib->names->close(ib->names, 0);
+	ret = ib->words->close(ib->words, 0);
+	g_free(ib);
+	return ret;
+}
+
+void ibex_unindex (ibex *ib, char *name)
+{
+	printf("trying to unindex '%s'\n", name);
+	if (db_contains_word(ib->names, NULL, name)) {
+		/* FIXME: do within transaction? */
+		db_delete_name(ib->words, name);
+		db_delete_word(ib->names, name);
+	}
+}
+
+GPtrArray *ibex_find (ibex *ib, char *word)
+{
+	char *normal;
+	int len;
+
+	len = strlen(word);
+	normal = alloca(len+1);
+	ibex_normalise_word(word, word+len, normal);
+	return db_find(ib->words, normal);
+}
+
+gboolean ibex_find_name (ibex *ib, char *name, char *word)
+{
+	char *normal;
+	int len;
+
+	len = strlen(word);
+	normal = alloca(len+1);
+	ibex_normalise_word(word, word+len, normal);
+	return db_contains_word(ib->words, name, normal);
+}
+
+gboolean ibex_contains_name(ibex *ib, char *name)
+{
+	return db_contains_word(ib->names, NULL, name);
+}