transmission/libtransmission/list.c

/*
 * This file Copyright (C) 2007 Charles Kerr <charles@rebelbase.com>
 *
 * This file is licensed by the GPL version 2.  Works owned by the
 * Transmission project are granted a special exemption to clause 2(b)
 * so that the bulk of its code can remain under the MIT license. 
 * This exemption does not extend to derived works not owned by
 * the Transmission project.
 *
 * $Id$
 */

#include "transmission.h"
#include "list.h"
#include "utils.h"

static tr_list*
node_alloc( void )
{
    return tr_new0( tr_list, 1 );
}

static void
node_free( tr_list* node )
{
    tr_free( node );
}

/***
****
***/

void
tr_list_free( tr_list** list )
{
    while( *list )
    {
        tr_list * node = *list;
        *list = (*list)->next;
        node_free( node );
    }
}

void
tr_list_prepend( tr_list ** list, void * data )
{
    tr_list * node = node_alloc ();
    node->data = data;
    node->next = *list;
    if( *list )
        (*list)->prev = node;
    *list = node;
}

void
tr_list_append( tr_list ** list, void * data )
{
    tr_list * node = node_alloc( );
    node->data = data;
    if( !*list )
        *list = node;
    else {
        tr_list * l = *list;
        while( l->next )
            l = l->next;
        l->next = node;
        node->prev = l;
    }
}

void
tr_list_insert_sorted( tr_list ** list,
                       void       * data,
                       int          compare(const void*,const void*) )
{
    /* find l, the node that we'll insert this data before */
    tr_list * l;
    for( l=*list; l!=NULL; l=l->next ) {
        const int c = (compare)( data, l->data );
        if( c <= 0 )
            break;
    }

    if( l == NULL)
        tr_list_append( list, data );
    else if( l == *list )
        tr_list_prepend( list, data );
    else {
        tr_list * node = node_alloc( );
        node->data = data;
        if( l->prev ) { node->prev = l->prev; node->prev->next = node; }
        node->next = l;
        l->prev = node;
    }
}


tr_list*
tr_list_find_data ( tr_list * list, const void * data )
{
    for(; list; list=list->next )
        if( list->data == data )
            return list;

    return NULL;
}

static void*
tr_list_remove_node ( tr_list ** list, tr_list * node )
{
    void * data;
    tr_list * prev = node ? node->prev : NULL;
    tr_list * next = node ? node->next : NULL;
    if( prev ) prev->next = next;
    if( next ) next->prev = prev;
    if( *list == node ) *list = next;
    data = node ? node->data : NULL;
    node_free( node );
    return data;
}

void*
tr_list_pop_front( tr_list ** list )
{
    void * ret = NULL;
    if( *list != NULL )
    {
        ret = (*list)->data;
        tr_list_remove_node( list, *list );
    }
    return ret;
}

void*
tr_list_remove_data ( tr_list ** list, const void * data )
{
    return tr_list_remove_node( list, tr_list_find_data( *list, data ) );
}

void*
tr_list_remove( tr_list         ** list,
                const void       * b,
                TrListCompareFunc  compare_func )
{
    return tr_list_remove_node( list, tr_list_find( *list, b, compare_func ) );
}


tr_list*
tr_list_find ( tr_list * list , const void * b, TrListCompareFunc func )
{
    for( ; list; list=list->next )
        if( !func( list->data, b ) )
            return list;

    return NULL;
}

void
tr_list_foreach( tr_list * list, TrListForeachFunc func )
{
    while( list != NULL ) {
        func( list->data );
        list = list->next;
    }
}

int
tr_list_size( const tr_list * list )
{
    int size = 0;
    while( list != NULL ) {
        ++size;
        list = list->next;
    }
    return size;
}