text: /* $FreeBSD: releng/11.1/lib/libc/iconv/citrus_db_factory.c 267437 2014-06-13 08:28:51Z tijl $ */
  /*	$NetBSD: citrus_db_factory.c,v 1.10 2013/09/14 13:05:51 joerg Exp $	*/
  
  /*-
   * Copyright (c)2003 Citrus Project,
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  #include <sys/cdefs.h>
  #include <sys/types.h>
  #include <sys/queue.h>
  
  #include <arpa/inet.h>
  #include <assert.h>
  #include <errno.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  
  #include "citrus_namespace.h"
  #include "citrus_region.h"
  #include "citrus_db_file.h"
  #include "citrus_db_factory.h"
  
  struct _citrus_db_factory_entry {
  	STAILQ_ENTRY(_citrus_db_factory_entry)	 de_entry;
  	struct _citrus_db_factory_entry		*de_next;
  	uint32_t				 de_hashvalue;
  	struct _region				 de_key;
  	int					 de_key_free;
  	struct _region				 de_data;
  	int					 de_data_free;
  	int					de_idx;
  };
  
  struct _citrus_db_factory {
  	size_t					 df_num_entries;
  	STAILQ_HEAD(, _citrus_db_factory_entry)	 df_entries;
  	size_t					 df_total_key_size;
  	size_t					 df_total_data_size;
  	uint32_t (*df_hashfunc)(struct _citrus_region *);
  	void					*df_hashfunc_closure;
  };
  
  #define DB_ALIGN 16
  
  int
  _citrus_db_factory_create(struct _citrus_db_factory **rdf,
      _citrus_db_hash_func_t hashfunc, void *hashfunc_closure)
  {
  	struct _citrus_db_factory *df;
  
  	df = malloc(sizeof(*df));
  	if (df == NULL)
  		return (errno);
  	df->df_num_entries = 0;
  	df->df_total_key_size = df->df_total_data_size = 0;
  	STAILQ_INIT(&df->df_entries);
  	df->df_hashfunc = hashfunc;
  	df->df_hashfunc_closure = hashfunc_closure;
  
  	*rdf = df;
  
  	return (0);
  }
  
  void
  _citrus_db_factory_free(struct _citrus_db_factory *df)
  {
  	struct _citrus_db_factory_entry *de;
  
  	while ((de = STAILQ_FIRST(&df->df_entries)) != NULL) {
  		STAILQ_REMOVE_HEAD(&df->df_entries, de_entry);
  		if (de->de_key_free)
  			free(_region_head(&de->de_key));
  		if (de->de_data_free)
  			free(_region_head(&de->de_data));
  		free(de);
  	}
  	free(df);
  }
  
  static __inline size_t
  ceilto(size_t sz)
  {
  	return ((sz + DB_ALIGN - 1) & ~(DB_ALIGN - 1));
  }
  
  int
  _citrus_db_factory_add(struct _citrus_db_factory *df, struct _region *key,
      int keyfree, struct _region *data, int datafree)
  {
  	struct _citrus_db_factory_entry *de;
  
  	de = malloc(sizeof(*de));
  	if (de == NULL)
  		return (-1);
  
  	de->de_hashvalue = df->df_hashfunc(key);
  	de->de_key = *key;
  	de->de_key_free = keyfree;
  	de->de_data = *data;
  	de->de_data_free = datafree;
  	de->de_idx = -1;
  
  	STAILQ_INSERT_TAIL(&df->df_entries, de, de_entry);
  	df->df_total_key_size += _region_size(key);
  	df->df_total_data_size += ceilto(_region_size(data));
  	df->df_num_entries++;
  
  	return (0);
  
  }
  
  int
  _citrus_db_factory_add_by_string(struct _citrus_db_factory *df,
      const char *key, struct _citrus_region *data, int datafree)
  {
  	struct _region r;
  	char *tmp;
  
  	tmp = strdup(key);
  	if (tmp == NULL)
  		return (errno);
  	_region_init(&r, tmp, strlen(key));
  	return _citrus_db_factory_add(df, &r, 1, data, datafree);
  }
  
  int
  _citrus_db_factory_add8_by_string(struct _citrus_db_factory *df,
      const char *key, uint8_t val)
  {
  	struct _region r;
  	uint8_t *p;
  
  	p = malloc(sizeof(*p));
  	if (p == NULL)
  		return (errno);
  	*p = val;
  	_region_init(&r, p, 1);
  	return (_citrus_db_factory_add_by_string(df, key, &r, 1));
  }
  
  int
  _citrus_db_factory_add16_by_string(struct _citrus_db_factory *df,
      const char *key, uint16_t val)
  {
  	struct _region r;
  	uint16_t *p;
  
  	p = malloc(sizeof(*p));
  	if (p == NULL)
  		return (errno);
  	*p = htons(val);
  	_region_init(&r, p, 2);
  	return (_citrus_db_factory_add_by_string(df, key, &r, 1));
  }
  
  int
  _citrus_db_factory_add32_by_string(struct _citrus_db_factory *df,
      const char *key, uint32_t val)
  {
  	struct _region r;
  	uint32_t *p;
  
  	p = malloc(sizeof(*p));
  	if (p == NULL)
  		return (errno);
  	*p = htonl(val);
  	_region_init(&r, p, 4);
  	return (_citrus_db_factory_add_by_string(df, key, &r, 1));
  }
  
  int
  _citrus_db_factory_add_string_by_string(struct _citrus_db_factory *df,
      const char *key, const char *data)
  {
  	char *p;
  	struct _region r;
  
  	p = strdup(data);
  	if (p == NULL)
  		return (errno);
  	_region_init(&r, p, strlen(p) + 1);
  	return (_citrus_db_factory_add_by_string(df, key, &r, 1));
  }
  
  size_t
  _citrus_db_factory_calc_size(struct _citrus_db_factory *df)
  {
  	size_t sz;
  
  	sz = ceilto(_CITRUS_DB_HEADER_SIZE);
  	sz += ceilto(_CITRUS_DB_ENTRY_SIZE * df->df_num_entries);
  	sz += ceilto(df->df_total_key_size);
  	sz += df->df_total_data_size;
  
  	return (sz);
  }
  
  static __inline void
  put8(struct _region *r, size_t *rofs, uint8_t val)
  {
  
  	*(uint8_t *)_region_offset(r, *rofs) = val;
  	*rofs += 1;
  }
  
  static __inline void
  put32(struct _region *r, size_t *rofs, uint32_t val)
  {
  
  	val = htonl(val);
  	memcpy(_region_offset(r, *rofs), &val, 4);
  	*rofs += 4;
  }
  
  static __inline void
  putpad(struct _region *r, size_t *rofs)
  {
  	size_t i;
  
  	for (i = ceilto(*rofs) - *rofs; i > 0; i--)
  		put8(r, rofs, 0);
  }
  
  static __inline void
  dump_header(struct _region *r, const char *magic, size_t *rofs,
      size_t num_entries)
  {
  
  	while (*rofs<_CITRUS_DB_MAGIC_SIZE)
  		put8(r, rofs, *magic++);
  	put32(r, rofs, num_entries);
  	put32(r, rofs, _CITRUS_DB_HEADER_SIZE);
  }
  
  int
  _citrus_db_factory_serialize(struct _citrus_db_factory *df, const char *magic,
      struct _region *r)
  {
  	struct _citrus_db_factory_entry *de, **depp, *det;
  	size_t dataofs, i, keyofs, nextofs, ofs;
  
  	ofs = 0;
  	/* check whether more than 0 entries exist */
  	if (df->df_num_entries == 0) {
  		dump_header(r, magic, &ofs, 0);
  		return (0);
  	}
  	/* allocate hash table */
  	depp = calloc(df->df_num_entries, sizeof(*depp));
  	if (depp == NULL)
  		return (-1);
  
  	/* step1: store the entries which are not conflicting */
  	STAILQ_FOREACH(de, &df->df_entries, de_entry) {
  		de->de_hashvalue %= df->df_num_entries;
  		de->de_idx = -1;
  		de->de_next = NULL;
  		if (depp[de->de_hashvalue] == NULL) {
  			depp[de->de_hashvalue] = de;
  			de->de_idx = (int)de->de_hashvalue;
  		}
  	}
  
  	/* step2: resolve conflicts */
  	i = 0;
  	STAILQ_FOREACH(de, &df->df_entries, de_entry) {
  		if (de->de_idx == -1) {
  			det = depp[de->de_hashvalue];
  			while (det->de_next != NULL)
  				det = det->de_next;
  			det->de_next = de;
  			while (depp[i] != NULL)
  				i++;
  			depp[i] = de;
  			de->de_idx = (int)i;
  		}
  	}
  
  	keyofs = _CITRUS_DB_HEADER_SIZE +
  	    ceilto(df->df_num_entries*_CITRUS_DB_ENTRY_SIZE);
  	dataofs = keyofs + ceilto(df->df_total_key_size);
  
  	/* dump header */
  	dump_header(r, magic, &ofs, df->df_num_entries);
  
  	/* dump entries */
  	for (i = 0; i < df->df_num_entries; i++) {
  		de = depp[i];
  		nextofs = 0;
  		if (de->de_next) {
  			nextofs = _CITRUS_DB_HEADER_SIZE +
  			    de->de_next->de_idx * _CITRUS_DB_ENTRY_SIZE;
  		}
  		put32(r, &ofs, de->de_hashvalue);
  		put32(r, &ofs, nextofs);
  		put32(r, &ofs, keyofs);
  		put32(r, &ofs, _region_size(&de->de_key));
  		put32(r, &ofs, dataofs);
  		put32(r, &ofs, _region_size(&de->de_data));
  		memcpy(_region_offset(r, keyofs),
  		    _region_head(&de->de_key), _region_size(&de->de_key));
  		keyofs += _region_size(&de->de_key);
  		memcpy(_region_offset(r, dataofs),
  		    _region_head(&de->de_data), _region_size(&de->de_data));
  		dataofs += _region_size(&de->de_data);
  		putpad(r, &dataofs);
  	}
  	putpad(r, &ofs);
  	putpad(r, &keyofs);
  	free(depp);
  
  	return (0);
  }
  