io.c

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 *	multi_dest_index_set (which is used only inside glimpse) must be malloced separately.
 */
initialize_data_structures(files)
int	files;
{
	FILEMASK_SIZE = ((files + 1)/(8*sizeof(int)) + 4);
	REAL_PARTITION = (FILEMASK_SIZE + 4);
	if (REAL_PARTITION < MAX_PARTITION + 2) REAL_PARTITION = MAX_PARTITION + 2;
	REAL_INDEX_BUF = ((files + 1)*3 + 3*8*sizeof(int)  + 6*MAX_WORD_BUF + 2);	/* index line length with OneFilePerBlock (and/or ByteLevelIndex) */
	/* increased by *3 + 24*sizeof(int) to avoid segfaults --GV */
	if (REAL_INDEX_BUF < MAX_SORTLINE_LEN) REAL_INDEX_BUF = MAX_SORTLINE_LEN;
	MAX_ALL_INDEX = (REAL_INDEX_BUF / 2);
	if (src_index_set == NULL) src_index_set = (unsigned int *)my_malloc(sizeof(int)*REAL_PARTITION);
	memset(src_index_set, '\0', sizeof(int) * REAL_PARTITION);
	if (dest_index_set == NULL) dest_index_set = (unsigned int *)my_malloc(sizeof(int)*REAL_PARTITION);
	memset(dest_index_set, '\0', sizeof(int) * REAL_PARTITION);

/* malloc a few extra bytes above REAL_INDEX_BUF */
/* the value of REAL_INDEX_BUF is used to terminate loops, but in the loop up to 4 chars may be assigned */
	if (src_index_buf == NULL) src_index_buf = (unsigned char *)my_malloc(sizeof(char)*(REAL_INDEX_BUF+4));
	memset(src_index_buf, '\0', sizeof(char)*(REAL_INDEX_BUF+4));
	if (dest_index_buf == NULL) dest_index_buf = (unsigned char *)my_malloc(sizeof(char)*(REAL_INDEX_BUF + 4));
	memset(dest_index_buf, '\0', sizeof(char)*(REAL_INDEX_BUF+4));
	if (merge_index_buf == NULL) merge_index_buf = (unsigned char *)my_malloc(sizeof(char)*(REAL_INDEX_BUF + 4));
	memset(merge_index_buf, '\0', sizeof(char)*(REAL_INDEX_BUF+4));
}

destroy_data_structures()
{
	if (src_index_set != NULL) free(src_index_set);
	src_index_set = NULL;
	if (dest_index_set != NULL) free(dest_index_set);
	dest_index_set = NULL;
	if (src_index_buf != NULL) free(src_index_buf);
	src_index_buf = NULL;
	if (dest_index_buf != NULL) free(dest_index_buf);
	dest_index_buf = NULL;
	if (merge_index_buf != NULL) free(merge_index_buf);
	merge_index_buf = NULL;
}

/* We MUST be able to parse name as: "goodoldunixfilename firstwordofotherinfo restofotherinfo_whichifNULL_willnotbeprecededbyblanklikeitdoeshere\n" */
/* len is strlen(name), being points to                   ^ and end points to ^: the firstwordofotherinfo can be used to create .glimpse_filehash when -U ON */
/* Restriction: the 3 strings above cannot contain '\n' or '\0' or ' ' */
/* returns 0 if parsing was successful, -1 if error */
/* begin/end values are NOT stored for each file (painful!), so this function may be called multiple times for the same name: caller MUST save if reqd. */
int
special_parse_name(name, len, begin, end)
	char	*name;
	int	len;
	int	*begin, *end;
{
	int	i;
	int	index;

	*begin = -1;
	*end = -1;
	if (InfoAfterFilename || ExtractInfo) {	/* Glimpse will ALWAYS terminate filename at first blank (no ' ', '\n', '\0' in filename) */
		/* Trying to use FILE_END_MARK instead of blank! --GB 6/7/99 */
		for (i=0; i<len; i++) {
			if (name[i] == '\n') break;
			if (name[i] == FILE_END_MARK)  {
				if (*begin == -1) {
					*begin = i+1;
					if (!InfoAfterFilename) break;	/* don't care about URL since it doesn't exist as far as I know */
				}
				else {
					*end = i;
					break;
				}
			}
		}
		if (*begin == -1) {
			*begin = 0; *end = len;
			return 0;
		}
		else {
			if (*end == -1) *end = len;
			if (*begin >= *end) {
				*end = *begin - 1; *begin = 0;
				/* was returning -1 before, but if can't find any "firstwordofinfo", then just use the first word in buffer for indexing... */
			}
			return 0;
		}
	}
	else {
		*begin = 0; *end = len;
		return 0;
	}
}

/* Puts the actual name of the file in the file-system into temp (caller must pass buffer that is large enough to hold it...) */
int
special_get_name(name, len, temp)
	char	*name;
	int	len;
	char	*temp;
{
	int	begin=-1, end=-1;
	if (name == NULL) return -1;
	if (len < 0) len = strlen(name);
	if (len <= 0) {
		errno = EINVAL;
		return -1;
	}
	if (special_parse_name(name, len, &begin, &end) == -1) return -1;
	if ((begin >= MAX_LINE_LEN) || (len >= MAX_LINE_LEN)) {
		errno = ENAMETOOLONG;
		return -1;
	}
	if (begin > 0) {	/* points to first element of the information (like URL) stored after filename */
		memcpy(temp, name, begin-1);
		temp[begin-1] = '\0';
	}
	else {	/* no other information stored with filename */
		memcpy(temp, name, len);
		temp[len] = '\0';
	}
	return 0;
}

/* Must NOT write into name or flag since they may be passed as "const" char* on some systems */
FILE *
my_fopen(name, flag)
	char	*name;
	char	*flag;
{
	int	len;
	char	temp[MAX_LINE_LEN];

	if (name == NULL) return NULL;
	len = strlen(name);
	if (special_get_name(name, len, temp) == -1) return NULL;
	return fopen(temp, flag);
}

int
my_open(name, flag, mode)
	char	*name;
	int	flag, mode;
{
	int	len;
	char	temp[MAX_LINE_LEN];

	if (name == NULL) return -1;
	len = strlen(name);
	if (special_get_name(name, len, temp) == -1) return -1;
	return open(temp, flag, mode);
}

int
my_stat(name, buf)
	char	*name;
	struct stat *buf;
{
	int	len;
	char	temp[MAX_LINE_LEN];

	if (name == NULL) return -1;
	len = strlen(name);
	if (special_get_name(name, len, temp) == -1) return -1;
	return stat(temp, buf);
}

int
my_lstat(name, buf)
	char	*name;
	struct stat *buf;
{
	int	len;
	char	temp[MAX_LINE_LEN];

	if (name == NULL) return -1;
	len = strlen(name);
	if (special_get_name(name, len, temp) == -1) return -1;
	return lstat(temp, buf);
}

/* Changed hash-routines to look at exactly that portion of the filename that occurs before the first blank character, */
/* and use that to compare names: Oct/96 --- But lose efficiency since must parse name everytime: at least 1 string copy */
/* Using FILE_END_MARK instead of blank. --GB 6/7/99 */
name_hashelement *name_hashtable[MAX_64K_HASH];	/* if (!BigFilenameHashTable) then only the first 4K entries in it are used */

/*
 * Returns the index of the name if the it is found amongst the set
 * of files in name_array; -1 otherwise.
 */
int
get_filename_index(name)
	char	*name;
{
	int	index;
	int	len;
	int	i, begin=-1, end=-1;
	/* int	skips=0; */
	name_hashelement	*e;
	char	*temp;
	int	temp_len;

	if (name == NULL) return -1;
	len = strlen(name);
	if (special_parse_name(name, len, &begin, &end) == -1) return -1;
	if ((begin >= MAX_LINE_LEN) || (len >= MAX_LINE_LEN)) {
		errno = ENAMETOOLONG;
		return -1;
	}
	temp = name;
	if (begin > 0) {	/* points to first element of the information (like URL) stored after filename */
		temp_len = begin - 1;
	}
	else {	/* no other information stored with filename */
		temp_len = len;
	}

	if (FirstWordOfInfoIsKey) index = hashNk(name, end-begin);
	else {	/* hash on filename */
		if (begin <= 0) index = hashNk(name, len);
		else index = hashNk(name, begin-1);
	}
	e = name_hashtable[index];
	while((e != NULL) && (strncmp(temp, e->name, temp_len))) {
		/* skips ++; */
		e = e->next;
	}
	/* fprintf(STATFILE, "skips = %d\n", skips); */
	if (e == NULL) return -1;
	return e->index;
}

insert_filename(name, name_index)
	char	*name;
	int	name_index;
{
	int	len;
	int	index;
	int	i, begin=-1, end=-1;
	name_hashelement **pe;
	char	*temp;
	int	temp_len;

	if (name == NULL) return;
	len = strlen(name);
	if (special_parse_name(name, len, &begin, &end) == -1) return;
	if ((begin >= MAX_LINE_LEN) || (len >= MAX_LINE_LEN)) {
		errno = ENAMETOOLONG;
		return;
	}
	temp = name;
	if (begin > 0) {	/* points to first element of the information (like URL) stored after filename */
		temp_len = begin - 1;
	}
	else {	/* no other information stored with filename */
		temp_len = len;
	}

	if (FirstWordOfInfoIsKey) index = hashNk(name, end-begin);
	else {	/* hash on filename */
		if (begin <= 0) index = hashNk(name, len);
		else index = hashNk(name, begin-1);
	}
	pe = &name_hashtable[index];
	while((*pe != NULL) && (strncmp((*pe)->name, temp, temp_len))) pe = &(*pe)->next;
	if ((*pe) != NULL) return;
	if ((*pe = (name_hashelement *)my_malloc(sizeof(name_hashelement))) == NULL) {
		fprintf(stderr, "malloc failure in insert_filename %s:%d\n", __FILE__, __LINE__);
		exit(2);
	}
	(*pe)->next = NULL;
#if	0
	if (((*pe)->name = (char *)my_malloc(len + 2)) == NULL) {
		fprintf(stderr, "malloc failure in insert_filename %s:%d\n", __FILE__, __LINE__);
		exit(2);
	}
	strcpy((*pe)->name, name);
#else
	(*pe)->name = name;
#endif
	(*pe)->name_len = strlen(name);
	(*pe)->index = name_index;
}

change_filename(name, len, index, newname)
	char	*name;
	int	len;
	int	index;
	char	*newname;
{
	name_hashelement **pe, *t;
	char	temp[MAX_LINE_LEN];
	int	temp_len;

	if (special_get_name(name, len, temp) == -1) return;
	temp_len = strlen(temp);
	pe = &name_hashtable[index];
	while((*pe != NULL) && (strncmp((*pe)->name, temp, temp_len))) pe = &(*pe)->next;
	if ((*pe) == NULL) return;
#if	0
	my_free((*pe)->name);
#endif
	(*pe)->name = newname;
	return;
}

delete_filename(name, name_index)
	char	*name;
	int	name_index;
{
	int	len;
	int	index;
	int	i, begin=-1, end=-1;
	name_hashelement **pe, *t;
	char	*temp;
	int	temp_len;

	if (name == NULL) return;
	len = strlen(name);
	if (special_parse_name(name, len, &begin, &end) == -1) return;
	if ((begin >= MAX_LINE_LEN) || (len >= MAX_LINE_LEN)) {
		errno = ENAMETOOLONG;
		return;
	}
	temp = name;
	if (begin > 0) {	/* points to first element of the information (like URL) stored after filename */
		temp_len = begin - 1;
	}
	else {	/* no other information stored with filename */
		temp_len = len;
	}

	if (FirstWordOfInfoIsKey) index = hashNk(name, end-begin);
	else {	/* hash on filename */
		if (begin <= 0) index = hashNk(name, len);
		else index = hashNk(name, begin-1);
	}
	pe = &name_hashtable[index];
	while((*pe != NULL) && (strncmp((*pe)->name, temp, temp_len))) pe = &(*pe)->next;
	if ((*pe) == NULL) return;
	t = *pe;
	*pe = (*pe)->next;
#if	0
	my_free(t->name);
#endif
	my_free(t, sizeof(name_hashelement));
	return;
}

init_filename_hashtable()
{
	int	i;
	for (i=0; i<MAX_64K_HASH; i++) name_hashtable[i] = NULL;
}

int	built_filename_hashtable = 0;
build_filename_hashtable(names, num)
	char	**names[];
	int	num;
{
	int	i;

	init_filename_hashtable();
	for (i=0; i<num; i++) insert_filename(LIST_GET(names, i), i);
	built_filename_hashtable = 1;
}

destroy_filename_hashtable()
{
	int	i;
	name_hashelement **pe, *t;

	for (i=0; i<MAX_64K_HASH; i++) {
		pe = &name_hashtable[i];
		while(*pe!=NULL) {
			t = *pe;
			*pe = (*pe)->next;
#if	0
			my_free(t->name);
#endif
			my_free(t, sizeof(name_hashelement));
		}
		*pe = NULL;
	}
	built_filename_hashtable = 0;
}

long
get_file_time(fp, stbuf, name, i)
	FILE	*fp;
	struct stat *stbuf;
	char	*name;
	int	i;
{
	CHAR	array[sizeof(long)];
	int	xx;
	long	ret = 0;
	struct stat mystbuf;
	if (fp != NULL) {
		fseek(fp, i*sizeof(long), 0);
		fread(array, sizeof(long), 1, fp);
		for (xx=0; xx<sizeof(long); xx++) ret |= array[xx] << (8*(sizeof(long) - xx - 1));
	}
	else if (stbuf != NULL) {
		ret = stbuf->st_mtime;
	}
	else {
		if (my_stat(name, &mystbuf) == -1) ret = 0;
		else ret = mystbuf.st_mtime;
	}
	return ret;
}