summaryrefslogtreecommitdiff
path: root/libcaja-private/caja-file-queue.c
blob: 48fd6818c7f91a30d5b3f5a8580741ca0d821b5b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-

   Copyright (C) 2001 Maciej Stachowiak

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

   Author: Maciej Stachowiak <mjs@noisehavoc.org>
*/

#include <config.h>
#include "caja-file-queue.h"

#include <glib.h>

struct CajaFileQueue
{
    GList *head;
    GList *tail;
    GHashTable *item_to_link_map;
};

CajaFileQueue *
caja_file_queue_new (void)
{
    CajaFileQueue *queue;

    queue = g_new0 (CajaFileQueue, 1);
    queue->item_to_link_map = g_hash_table_new (g_direct_hash, g_direct_equal);

    return queue;
}

void
caja_file_queue_destroy (CajaFileQueue *queue)
{
    g_hash_table_destroy (queue->item_to_link_map);
    caja_file_list_free (queue->head);
    g_free (queue);
}

void
caja_file_queue_enqueue (CajaFileQueue *queue,
                         CajaFile      *file)
{
    if (g_hash_table_lookup (queue->item_to_link_map, file) != NULL)
    {
        /* It's already on the queue. */
        return;
    }

    if (queue->tail == NULL)
    {
        queue->head = g_list_append (NULL, file);
        queue->tail = queue->head;
    }
    else
    {
        queue->tail = g_list_append (queue->tail, file);
        queue->tail = queue->tail->next;
    }

    caja_file_ref (file);
    g_hash_table_insert (queue->item_to_link_map, file, queue->tail);
}

CajaFile *
caja_file_queue_dequeue (CajaFileQueue *queue)
{
    CajaFile *file;

    file = caja_file_queue_head (queue);
    caja_file_queue_remove (queue, file);

    return file;
}

void
caja_file_queue_remove (CajaFileQueue *queue,
                        CajaFile *file)
{
    GList *link;

    link = g_hash_table_lookup (queue->item_to_link_map, file);

    if (link == NULL)
    {
        /* It's not on the queue */
        return;
    }

    if (link == queue->tail)
    {
        /* Need to special-case removing the tail. */
        queue->tail = queue->tail->prev;
    }

    queue->head =  g_list_remove_link (queue->head, link);
    g_list_free (link);
    g_hash_table_remove (queue->item_to_link_map, file);

    caja_file_unref (file);
}

CajaFile *
caja_file_queue_head (CajaFileQueue *queue)
{
    if (queue->head == NULL)
    {
        return NULL;
    }

    return CAJA_FILE (queue->head->data);
}

gboolean
caja_file_queue_is_empty (CajaFileQueue *queue)
{
    return (queue->head == NULL);
}