/*-
 * Copyright (c) 1995 Alex Tatmanjants <alex@elvisti.kiev.ua>
 *		at Electronni Visti IA, Kiev, Ukraine.
 *			All rights reserved.
 *
 * Copyright (c) 2011 The FreeBSD Foundation
 * All rights reserved.
 * Portions of this software were developed by David Chisnall
 * under sponsorship from the FreeBSD Foundation.
 *
 * 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 ``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 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>
__FBSDID("$FreeBSD$");

#include "namespace.h"
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sysexits.h>
#include "un-namespace.h"

#include "collate.h"
#include "setlocale.h"
#include "ldpart.h"

#include "libc_private.h"

/*
 * To avoid modifying the original (single-threaded) code too much, we'll just
 * define the old globals as fields inside the table.
 *
 * We also modify the collation table test functions to search the thread-local
 * table first and the global table second.  
 */
#define __collate_substitute_nontrivial (table->__collate_substitute_nontrivial)
#define __collate_substitute_table_ptr (table->__collate_substitute_table_ptr)
#define __collate_char_pri_table_ptr (table->__collate_char_pri_table_ptr)
#define __collate_chain_pri_table (table->__collate_chain_pri_table)
int __collate_load_error;


struct xlocale_collate __xlocale_global_collate = {
	{{0}, "C"}, 1, 0
};

 struct xlocale_collate __xlocale_C_collate = {
	{{0}, "C"}, 1, 0
};

void __collate_err(int ex, const char *f) __dead2;

int
__collate_load_tables_l(const char *encoding, struct xlocale_collate *table);

static void
destruct_collate(void *t)
{
	struct xlocale_collate *table = t;
	if (__collate_chain_pri_table) {
		free(__collate_chain_pri_table);
	}
	free(t);
}

void *
__collate_load(const char *encoding, locale_t unused)
{
	if (strcmp(encoding, "C") == 0 || strcmp(encoding, "POSIX") == 0) {
		return &__xlocale_C_collate;
	}
	struct xlocale_collate *table = calloc(sizeof(struct xlocale_collate), 1);
	table->header.header.destructor = destruct_collate;
	// FIXME: Make sure that _LDP_CACHE is never returned.  We should be doing
	// the caching outside of this section
	if (__collate_load_tables_l(encoding, table) != _LDP_LOADED) {
		xlocale_release(table);
		return NULL;
	}
	return table;
}

/**
 * Load the collation tables for the specified encoding into the global table.
 */
int
__collate_load_tables(const char *encoding)
{
	int ret = __collate_load_tables_l(encoding, &__xlocale_global_collate);
	__collate_load_error = __xlocale_global_collate.__collate_load_error;
	return ret;
}

int
__collate_load_tables_l(const char *encoding, struct xlocale_collate *table)
{
	FILE *fp;
	int i, saverr, chains;
	uint32_t u32;
	char strbuf[STR_LEN], buf[PATH_MAX];
	void *TMP_substitute_table, *TMP_char_pri_table, *TMP_chain_pri_table;

	/* 'encoding' must be already checked. */
	if (strcmp(encoding, "C") == 0 || strcmp(encoding, "POSIX") == 0) {
		table->__collate_load_error = 1;
		return (_LDP_CACHE);
	}

	/* 'PathLocale' must be already set & checked. */
	/* Range checking not needed, encoding has fixed size */
	(void)strcpy(buf, _PathLocale);
	(void)strcat(buf, "/");
	(void)strcat(buf, encoding);
	(void)strcat(buf, "/LC_COLLATE");
	if ((fp = fopen(buf, "re")) == NULL)
		return (_LDP_ERROR);

	if (fread(strbuf, sizeof(strbuf), 1, fp) != 1) {
		saverr = errno;
		(void)fclose(fp);
		errno = saverr;
		return (_LDP_ERROR);
	}
	chains = -1;
	if (strcmp(strbuf, COLLATE_VERSION) == 0)
		chains = 0;
	else if (strcmp(strbuf, COLLATE_VERSION1_2) == 0)
		chains = 1;
	if (chains < 0) {
		(void)fclose(fp);
		errno = EFTYPE;
		return (_LDP_ERROR);
	}
	if (chains) {
		if (fread(&u32, sizeof(u32), 1, fp) != 1) {
			saverr = errno;
			(void)fclose(fp);
			errno = saverr;
			return (_LDP_ERROR);
		}
		if ((chains = (int)ntohl(u32)) < 1) {
			(void)fclose(fp);
			errno = EFTYPE;
			return (_LDP_ERROR);
		}
	} else
		chains = TABLE_SIZE;

	if ((TMP_substitute_table =
	     malloc(sizeof(__collate_substitute_table))) == NULL) {
		saverr = errno;
		(void)fclose(fp);
		errno = saverr;
		return (_LDP_ERROR);
	}
	if ((TMP_char_pri_table =
	     malloc(sizeof(__collate_char_pri_table))) == NULL) {
		saverr = errno;
		free(TMP_substitute_table);
		(void)fclose(fp);
		errno = saverr;
		return (_LDP_ERROR);
	}
	if ((TMP_chain_pri_table =
	     malloc(sizeof(*__collate_chain_pri_table) * chains)) == NULL) {
		saverr = errno;
		free(TMP_substitute_table);
		free(TMP_char_pri_table);
		(void)fclose(fp);
		errno = saverr;
		return (_LDP_ERROR);
	}

#define FREAD(a, b, c, d) \
{ \
	if (fread(a, b, c, d) != c) { \
		saverr = errno; \
		free(TMP_substitute_table); \
		free(TMP_char_pri_table); \
		free(TMP_chain_pri_table); \
		(void)fclose(d); \
		errno = saverr; \
		return (_LDP_ERROR); \
	} \
}

	FREAD(TMP_substitute_table, sizeof(__collate_substitute_table), 1, fp);
	FREAD(TMP_char_pri_table, sizeof(__collate_char_pri_table), 1, fp);
	FREAD(TMP_chain_pri_table,
	      sizeof(*__collate_chain_pri_table), chains, fp);
	(void)fclose(fp);

	if (__collate_substitute_table_ptr != NULL)
		free(__collate_substitute_table_ptr);
	__collate_substitute_table_ptr = TMP_substitute_table;
	if (__collate_char_pri_table_ptr != NULL)
		free(__collate_char_pri_table_ptr);
	__collate_char_pri_table_ptr = TMP_char_pri_table;
	for (i = 0; i < UCHAR_MAX + 1; i++) {
		__collate_char_pri_table[i].prim =
		    ntohl(__collate_char_pri_table[i].prim);
		__collate_char_pri_table[i].sec =
		    ntohl(__collate_char_pri_table[i].sec);
	}
	if (__collate_chain_pri_table != NULL)
		free(__collate_chain_pri_table);
	__collate_chain_pri_table = TMP_chain_pri_table;
	for (i = 0; i < chains; i++) {
		__collate_chain_pri_table[i].prim =
		    ntohl(__collate_chain_pri_table[i].prim);
		__collate_chain_pri_table[i].sec =
		    ntohl(__collate_chain_pri_table[i].sec);
	}
	__collate_substitute_nontrivial = 0;
	for (i = 0; i < UCHAR_MAX + 1; i++) {
		if (__collate_substitute_table[i][0] != i ||
		    __collate_substitute_table[i][1] != 0) {
			__collate_substitute_nontrivial = 1;
			break;
		}
	}
	table->__collate_load_error = 0;

	return (_LDP_LOADED);
}

u_char *
__collate_substitute(struct xlocale_collate *table, const u_char *s)
{
	int dest_len, len, nlen;
	int delta = strlen(s);
	u_char *dest_str = NULL;

	if (s == NULL || *s == '\0')
		return (__collate_strdup(""));
	delta += delta / 8;
	dest_str = malloc(dest_len = delta);
	if (dest_str == NULL)
		__collate_err(EX_OSERR, __func__);
	len = 0;
	while (*s) {
		nlen = len + strlen(__collate_substitute_table[*s]);
		if (dest_len <= nlen) {
			dest_str = reallocf(dest_str, dest_len = nlen + delta);
			if (dest_str == NULL)
				__collate_err(EX_OSERR, __func__);
		}
		(void)strcpy(dest_str + len, __collate_substitute_table[*s++]);
		len = nlen;
	}
	return (dest_str);
}

void
__collate_lookup(struct xlocale_collate *table, const u_char *t, int *len, int *prim, int *sec)
{
	struct __collate_st_chain_pri *p2;

	*len = 1;
	*prim = *sec = 0;
	for (p2 = __collate_chain_pri_table; p2->str[0] != '\0'; p2++) {
		if (*t == p2->str[0] &&
		    strncmp(t, p2->str, strlen(p2->str)) == 0) {
			*len = strlen(p2->str);
			*prim = p2->prim;
			*sec = p2->sec;
			return;
		}
	}
	*prim = __collate_char_pri_table[*t].prim;
	*sec = __collate_char_pri_table[*t].sec;
}

u_char *
__collate_strdup(u_char *s)
{
	u_char *t = strdup(s);

	if (t == NULL)
		__collate_err(EX_OSERR, __func__);
	return (t);
}

void
__collate_err(int ex, const char *f)
{
	const char *s;
	int serrno = errno;

	s = _getprogname();
	_write(STDERR_FILENO, s, strlen(s));
	_write(STDERR_FILENO, ": ", 2);
	s = f;
	_write(STDERR_FILENO, s, strlen(s));
	_write(STDERR_FILENO, ": ", 2);
	s = strerror(serrno);
	_write(STDERR_FILENO, s, strlen(s));
	_write(STDERR_FILENO, "\n", 1);
	exit(ex);
}

#ifdef COLLATE_DEBUG
void
__collate_print_tables()
{
	int i;
	struct __collate_st_chain_pri *p2;

	printf("Substitute table:\n");
	for (i = 0; i < UCHAR_MAX + 1; i++)
	    if (i != *__collate_substitute_table[i])
		printf("\t'%c' --> \"%s\"\n", i,
		       __collate_substitute_table[i]);
	printf("Chain priority table:\n");
	for (p2 = __collate_chain_pri_table; p2->str[0] != '\0'; p2++)
		printf("\t\"%s\" : %d %d\n", p2->str, p2->prim, p2->sec);
	printf("Char priority table:\n");
	for (i = 0; i < UCHAR_MAX + 1; i++)
		printf("\t'%c' : %d %d\n", i, __collate_char_pri_table[i].prim,
		       __collate_char_pri_table[i].sec);
}
#endif