/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* Authors: Jeffrey Stedfast <fejj@ximian.com>
*
* Copyright 2003 Ximian, Inc. (www.ximian.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Street #330, Boston, MA 02111-1307, USA.
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <glib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "e-util/e-memory.h"
#include "camel/camel-charset-map.h"
#include "camel-iconv.h"
#define ICONV_CACHE_SIZE (16)
struct _iconv_cache_bucket {
struct _iconv_cache_bucket *next;
struct _iconv_cache_bucket *prev;
guint32 refcount:31;
guint32 used:1;
iconv_t cd;
char *key;
};
/* a useful website on charset alaises:
* http://www.li18nux.org/subgroups/sa/locnameguide/v1.1draft/CodesetAliasTable-V11.html */
struct {
char *charset;
char *iconv_name;
} known_iconv_charsets[] = {
#if 0
/* charset name, iconv-friendly charset name */
{ "iso-8859-1", "iso-8859-1" },
{ "iso8859-1", "iso-8859-1" },
/* the above mostly serves as an example for iso-style charsets,
but we have code that will populate the iso-*'s if/when they
show up in camel_iconv_charset_name() so I'm
not going to bother putting them all in here... */
{ "windows-cp1251", "cp1251" },
{ "windows-1251", "cp1251" },
{ "cp1251", "cp1251" },
/* the above mostly serves as an example for windows-style
charsets, but we have code that will parse and convert them
to their cp#### equivalents if/when they show up in
camel_iconv_charset_name() so I'm not going to bother
putting them all in here either... */
#endif
/* charset name (lowercase!), iconv-friendly name (sometimes case sensitive) */
{ "utf-8", "UTF-8" },
{ "utf8", "UTF-8" },
/* 10646 is a special case, its usually UCS-2 big endian */
/* This might need some checking but should be ok for solaris/linux */
{ "iso-10646-1", "UCS-2BE" },
{ "iso_10646-1", "UCS-2BE" },
{ "iso10646-1", "UCS-2BE" },
{ "iso-10646", "UCS-2BE" },
{ "iso_10646", "UCS-2BE" },
{ "iso10646", "UCS-2BE" },
/* "ks_c_5601-1987" seems to be the most common of this lot */
{ "ks_c_5601-1987", "EUC-KR" },
{ "5601", "EUC-KR" },
{ "ksc-5601", "EUC-KR" },
{ "ksc-5601-1987", "EUC-KR" },
{ "ksc-5601_1987", "EUC-KR" },
/* FIXME: Japanese/Korean/Chinese stuff needs checking */
{ "euckr-0", "EUC-KR" },
{ "5601", "EUC-KR" },
{ "big5-0", "BIG5" },
{ "big5.eten-0", "BIG5" },
{ "big5hkscs-0", "BIG5HKCS" },
{ "gb2312-0", "gb2312" },
{ "gb2312.1980-0", "gb2312" },
{ "euc-cn", "gb2312" },
{ "gb18030-0", "gb18030" },
{ "gbk-0", "GBK" },
{ "eucjp-0", "eucJP" }, /* should this map to "EUC-JP" instead? */
{ "ujis-0", "ujis" }, /* we might want to map this to EUC-JP */
{ "jisx0208.1983-0", "SJIS" },
{ "jisx0212.1990-0", "SJIS" },
{ "pck", "SJIS" },
{ NULL, NULL }
};
static GHashTable *iconv_charsets;
static EMemChunk *cache_chunk;
static struct _iconv_cache_bucket *iconv_cache_buckets;
static GHashTable *iconv_cache;
static GHashTable *iconv_open_hash;
static unsigned int iconv_cache_size = 0;
#ifdef G_THREADS_ENABLED
static GStaticMutex iconv_cache_lock = G_STATIC_MUTEX_INIT;
static GStaticMutex iconv_charset_lock = G_STATIC_MUTEX_INIT;
#define ICONV_CACHE_LOCK() g_static_mutex_lock (&iconv_cache_lock)
#define ICONV_CACHE_UNLOCK() g_static_mutex_unlock (&iconv_cache_lock)
#define ICONV_CHARSET_LOCK() g_static_mutex_lock (&iconv_charset_lock)
#define ICONV_CHARSET_UNLOCK() g_static_mutex_unlock (&iconv_charset_lock)
#else
#define ICONV_CACHE_LOCK()
#define ICONV_CACHE_UNLOCK()
#define ICONV_CHARSET_LOCK()
#define ICONV_CHARSET_UNLOCK()
#endif /* G_THREADS_ENABLED */
/* caller *must* hold the iconv_cache_lock to call any of the following functions */
/**
* iconv_cache_bucket_new:
* @key: cache key
* @cd: iconv descriptor
*
* Creates a new cache bucket, inserts it into the cache and
* increments the cache size.
*
* Returns a pointer to the newly allocated cache bucket.
**/
static struct _iconv_cache_bucket *
iconv_cache_bucket_new (const char *key, iconv_t cd)
{
struct _iconv_cache_bucket *bucket;
bucket = e_memchunk_alloc (cache_chunk);
bucket->next = NULL;
bucket->prev = NULL;
bucket->key = g_strdup (key);
bucket->refcount = 1;
bucket->used = TRUE;
bucket->cd = cd;
g_hash_table_insert (iconv_cache, bucket->key, bucket);
/* FIXME: Since iconv_cache_expire_unused() traverses the list
from head to tail, perhaps it might be better to append new
nodes rather than prepending? This way older cache buckets
expire first? */
bucket->next = iconv_cache_buckets;
iconv_cache_buckets = bucket;
iconv_cache_size++;
return bucket;
}
/**
* iconv_cache_bucket_expire:
* @bucket: cache bucket
*
* Expires a single cache bucket @bucket. This should only ever be
* called on a bucket that currently has no used iconv descriptors
* open.
**/
static void
iconv_cache_bucket_expire (struct _iconv_cache_bucket *bucket)
{
g_hash_table_remove (iconv_cache, bucket->key);
if (bucket->prev) {
bucket->prev->next = bucket->next;
if (bucket->next)
bucket->next->prev = bucket->prev;
} else {
iconv_cache_buckets = bucket->next;
if (bucket->next)
bucket->next->prev = NULL;
}
g_free (bucket->key);
g_iconv_close (bucket->cd);
e_memchunk_free (cache_chunk, bucket);
iconv_cache_size--;
}
/**
* iconv_cache_expire_unused:
*
* Expires as many unused cache buckets as it needs to in order to get
* the total number of buckets < ICONV_CACHE_SIZE.
**/
static void
iconv_cache_expire_unused (void)
{
struct _iconv_cache_bucket *bucket, *next;
bucket = iconv_cache_buckets;
while (bucket && iconv_cache_size >= ICONV_CACHE_SIZE) {
next = bucket->next;
if (bucket->refcount == 0)
iconv_cache_bucket_expire (bucket);
bucket = next;
}
}
static void
iconv_charset_free (char *name, char *iname, gpointer user_data)
{
g_free (name);
g_free (iname);
}
void
camel_iconv_shutdown (void)
{
struct _iconv_cache_bucket *bucket, *next;
g_hash_table_foreach (iconv_charsets, (GHFunc) iconv_charset_free, NULL);
g_hash_table_destroy (iconv_charsets);
bucket = iconv_cache_buckets;
while (bucket) {
next = bucket->next;
g_free (bucket->key);
g_iconv_close (bucket->cd);
e_memchunk_free (cache_chunk, bucket);
bucket = next;
}
g_hash_table_destroy (iconv_cache);
g_hash_table_destroy (iconv_open_hash);
e_memchunk_destroy (cache_chunk);
}
/**
* camel_iconv_init:
*
* Initialize Camel's iconv cache. This *MUST* be called before any
* camel-iconv interfaces will work correctly.
**/
void
camel_iconv_init (void)
{
static int initialized = FALSE;
char *from, *to;
int i;
if (initialized)
return;
iconv_charsets = g_hash_table_new (g_str_hash, g_str_equal);
for (i = 0; known_iconv_charsets[i].charset != NULL; i++) {
from = g_strdup (known_iconv_charsets[i].charset);
to = g_strdup (known_iconv_charsets[i].iconv_name);
g_ascii_strdown (from, -1);
g_hash_table_insert (iconv_charsets, from, to);
}
iconv_cache_buckets = NULL;
iconv_cache = g_hash_table_new (g_str_hash, g_str_equal);
iconv_open_hash = g_hash_table_new (g_direct_hash, g_direct_equal);
cache_chunk = e_memchunk_new (ICONV_CACHE_SIZE, sizeof (struct _iconv_cache_bucket));
initialized = TRUE;
}
/**
* camel_iconv_charset_name:
* @charset: charset name
*
* Maps charset names to the names that glib's g_iconv_open() is more
* likely able to handle.
*
* Returns an iconv-friendly name for @charset.
**/
const char *
camel_iconv_charset_name (const char *charset)
{
char *name, *iname, *tmp;
if (charset == NULL)
return NULL;
name = g_alloca (strlen (charset) + 1);
strcpy (name, charset);
g_ascii_strdown (name, -1);
ICONV_CHARSET_LOCK ();
if ((iname = g_hash_table_lookup (iconv_charsets, name)) != NULL) {
ICONV_CHARSET_UNLOCK ();
return iname;
}
/* Unknown, try to convert some basic charset types to something that should work */
if (!strncmp (name, "iso", 3)) {
/* camel_charset_canonical_name() can handle this case */
ICONV_CHARSET_UNLOCK ();
return camel_charset_canonical_name (charset);
} else if (strncmp (name, "windows-", 8) == 0) {
/* Convert windows-#### or windows-cp#### to cp#### */
tmp = name + 8;
if (!strncmp (tmp, "cp", 2))
tmp += 2;
iname = g_strdup_printf ("CP%s", tmp);
} else if (strncmp (name, "microsoft-", 10) == 0) {
/* Convert microsoft-#### or microsoft-cp#### to cp#### */
tmp = name + 10;
if (!strncmp (tmp, "cp", 2))
tmp += 2;
iname = g_strdup_printf ("CP%s", tmp);
} else {
/* Just assume its ok enough as is, case and all - let g_iconv_open() handle this */
iname = g_strdup (charset);
}
g_hash_table_insert (iconv_charsets, g_strdup (name), iname);
ICONV_CHARSET_UNLOCK ();
return iname;
}
/**
* camel_iconv_open:
* @to: charset to convert to
* @from: charset to convert from
*
* Allocates a coversion descriptor suitable for converting byte
* sequences from charset @from to charset @to. The resulting
* descriptor can be used with iconv (or the camel_iconv wrapper) any
* number of times until closed using camel_iconv_close.
*
* Returns a new conversion descriptor for use with iconv on success
* or (iconv_t) -1 on fail as well as setting an appropriate errno
* value.
**/
iconv_t
camel_iconv_open (const char *to, const char *from)
{
struct _iconv_cache_bucket *bucket;
iconv_t cd;
char *key;
if (from == NULL || to == NULL) {
errno = EINVAL;
return (iconv_t) -1;
}
if (!strcasecmp (from, "x-unknown"))
from = camel_charset_locale_name ();
/* Even tho g_iconv_open will find the appropriate charset
* format(s) for the to/from charset strings (hahaha, yea
* right), we still convert them to their canonical format
* here so that our key is in a standard format */
from = camel_iconv_charset_name (from);
to = camel_iconv_charset_name (to);
key = g_alloca (strlen (from) + strlen (to) + 2);
sprintf (key, "%s:%s", from, to);
ICONV_CACHE_LOCK ();
bucket = g_hash_table_lookup (iconv_cache, key);
if (bucket) {
if (bucket->used) {
cd = g_iconv_open (to, from);
if (cd == (iconv_t) -1)
goto exception;
} else {
/* Apparently iconv on Solaris <= 7 segfaults if you pass in
* NULL for anything but inbuf; work around that. (NULL outbuf
* or NULL *outbuf is allowed by Unix98.)
*/
size_t inleft = 0, outleft = 0;
char *outbuf = NULL;
cd = bucket->cd;
bucket->used = TRUE;
/* reset the descriptor */
g_iconv (cd, NULL, &inleft, &outbuf, &outleft);
}
bucket->refcount++;
} else {
cd = g_iconv_open (to, from);
if (cd == (iconv_t) -1)
goto exception;
iconv_cache_expire_unused ();
bucket = iconv_cache_bucket_new (key, cd);
}
g_hash_table_insert (iconv_open_hash, cd, bucket->key);
ICONV_CACHE_UNLOCK ();
return cd;
exception:
ICONV_CACHE_UNLOCK ();
if (errno == EINVAL)
g_warning ("Conversion from '%s' to '%s' is not supported", from, to);
else
g_warning ("Could not open converter from '%s' to '%s': %s",
from, to, g_strerror (errno));
return cd;
}
/**
* camel_iconv:
* @cd: conversion descriptor
* @inbuf: address of input buffer
* @inleft: input bytes left
* @outbuf: address of output buffer
* @outleft: output bytes left
*
* Read `man 3 iconv`
**/
size_t
camel_iconv (iconv_t cd, const char **inbuf, size_t *inleft, char **outbuf, size_t *outleft)
{
return g_iconv (cd, (char **) inbuf, inleft, outbuf, outleft);
}
/**
* camel_iconv_close:
* @cd: iconv conversion descriptor
*
* Closes the iconv descriptor @cd.
*
* Returns 0 on success or -1 on fail as well as setting an
* appropriate errno value.
**/
int
camel_iconv_close (iconv_t cd)
{
struct _iconv_cache_bucket *bucket;
const char *key;
if (cd == (iconv_t) -1)
return 0;
ICONV_CACHE_LOCK ();
key = g_hash_table_lookup (iconv_open_hash, cd);
if (key) {
g_hash_table_remove (iconv_open_hash, cd);
bucket = g_hash_table_lookup (iconv_cache, key);
g_assert (bucket);
bucket->refcount--;
if (cd == bucket->cd)
bucket->used = FALSE;
else
g_iconv_close (cd);
if (!bucket->refcount && iconv_cache_size > ICONV_CACHE_SIZE) {
/* expire this cache bucket */
iconv_cache_bucket_expire (bucket);
}
} else {
ICONV_CACHE_UNLOCK ();
g_warning ("This iconv context wasn't opened using camel_iconv_open()");
return g_iconv_close (cd);
}
ICONV_CACHE_UNLOCK ();
return 0;
}
