Sylpheed

/*

 * LibSylph -- E-Mail client library

 * Copyright (C) 1999-2005 Hiroyuki Yamamoto

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#include <glib.h>

#include <string.h>

#include "stringtable.h"

#include "utils.h"

/* alfons - hashed string table (I wasn't content with GStringChunk;

 * can't recall why :-) */

#if 0

#define XXX_DEBUG \

        debug_print

#else

#define XXX_DEBUG \

        if (0) debug_print

#endif

typedef struct StringEntry_ {

        gint        ref_count;

        gchar  *string;

} StringEntry;

static StringEntry *string_entry_new(const gchar *str)

{

        StringEntry *entry;

        entry = g_new0(StringEntry, 1);

        entry->ref_count = 1;

        entry->string = g_strdup(str);

        return entry;

}

static void string_entry_free(StringEntry *entry)

{

        g_return_if_fail(entry != NULL);

        g_free(entry->string);

        g_free(entry);

}

StringTable *string_table_new(void)

{

        StringTable *strtable;

        strtable = g_new0(StringTable, 1);

        g_return_val_if_fail(strtable != NULL, NULL);

        strtable->hash_table = g_hash_table_new(g_str_hash, g_str_equal);

        g_return_val_if_fail(strtable->hash_table, NULL);

        return strtable;

}

gchar *string_table_lookup_string(StringTable *table, const gchar *str)

{

        StringEntry *entry;

        entry = g_hash_table_lookup(table->hash_table, str);

        if (entry) {

                return entry->string;

        } else {

                return NULL;

        }

}

gchar *string_table_insert_string(StringTable *table, const gchar *str)

{

        StringEntry *entry;

        entry = g_hash_table_lookup(table->hash_table, str);

        if (entry) {

                entry->ref_count++;

                XXX_DEBUG ("ref++ for %s (%d)\n", entry->string,

                           entry->ref_count);

        } else {

                entry = string_entry_new(str);

                XXX_DEBUG ("inserting %s\n", str);

                /* insert entry->string instead of str, since it can be

                 * invalid pointer after this. */

                g_hash_table_insert(table->hash_table, entry->string, entry);

        }

        return entry->string;

}

void string_table_free_string(StringTable *table, const gchar *str)

{

        StringEntry *entry;

        entry = g_hash_table_lookup(table->hash_table, str);

        if (entry) {

                entry->ref_count--;

                if (entry->ref_count <= 0) {

                        XXX_DEBUG ("refcount of string %s dropped to zero\n",

                                   entry->string);

                        g_hash_table_remove(table->hash_table, str);

                        string_entry_free(entry);

                } else {

                        XXX_DEBUG ("ref-- for %s (%d)\n", entry->string,

                                   entry->ref_count);

                }

        }

}

static gboolean string_table_remove_for_each_fn(gchar *key, StringEntry *entry,

                                                gpointer user_data)

{

        g_return_val_if_fail(key != NULL, TRUE);

        g_return_val_if_fail(entry != NULL, TRUE);

        string_entry_free(entry);

        return TRUE;

}

void string_table_free(StringTable *table)

{

        g_return_if_fail(table != NULL);

        g_return_if_fail(table->hash_table != NULL);

        g_hash_table_foreach_remove(table->hash_table,

                                    (GHRFunc)string_table_remove_for_each_fn,

                                    NULL);

        g_hash_table_destroy(table->hash_table);

        g_free(table);

}

static void string_table_stats_for_each_fn(gchar *key, StringEntry *entry,

                                           guint *totals)

{

        if (entry->ref_count > 1) {

                *totals += strlen(key) * (entry->ref_count - 1);

        }

}

void string_table_get_stats(StringTable *table)

{

        guint totals = 0;

        g_hash_table_foreach(table->hash_table,

                             (GHFunc)string_table_stats_for_each_fn, &totals);

        XXX_DEBUG ("TOTAL UNSPILLED %d (%dK)\n", totals, totals / 1024);

}