src/interface/dialog.c

   1 /*****************************************************************************
   2  * dialog.c: User dialog functions
   3  *****************************************************************************
   4  * Copyright © 2009 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 /**
  22  * \file dialog.c
  23  * User dialogs core
  24  */
  25
  26 #ifdef HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include <stdarg.h>
  31
  32 #include <vlc_common.h>
  33 #include <vlc_dialog.h>
  34 #include <vlc_extensions.h>
  35 #include <assert.h>
  36 #include "libvlc.h"
  37
  38 static vlc_mutex_t provider_lock = VLC_STATIC_MUTEX;
  39
  40 #undef dialog_Register
  41 /**
  42  * Registers an object as the dialog provider.
  43  * It is assumed that the appropriate variable callbacks are already
  44  * registered.
  45  */
  46 int dialog_Register (vlc_object_t *obj)
  47 {
  48     libvlc_priv_t *priv = libvlc_priv (obj->p_libvlc);
  49     int ret = VLC_EGENERIC;
  50
  51     vlc_mutex_lock (&provider_lock);
  52     if (priv->p_dialog_provider == NULL)
  53     {   /* Since the object is responsible for unregistering itself before
  54          * it terminates, at reference is not needed. */
  55         priv->p_dialog_provider = obj;
  56         ret = VLC_SUCCESS;
  57     }
  58     vlc_mutex_unlock (&provider_lock);
  59     return ret;
  60 }
  61
  62 #undef dialog_Unregister
  63 /**
  64  * Unregisters the dialog provider.
  65  * Note that unless you have unregistered the callbacks already, the provider
  66  * might still be in use by other threads. Also, you need to cancel all
  67  * pending dialogs yourself.
  68  */
  69 int dialog_Unregister (vlc_object_t *obj)
  70 {
  71     libvlc_priv_t *priv = libvlc_priv (obj->p_libvlc);
  72     int ret = VLC_EGENERIC;
  73
  74     vlc_mutex_lock (&provider_lock);
  75     if (priv->p_dialog_provider == obj)
  76     {
  77         priv->p_dialog_provider = NULL;
  78         ret = VLC_SUCCESS;
  79     }
  80     vlc_mutex_unlock (&provider_lock);
  81     return ret;
  82 }
  83
  84 static vlc_object_t *dialog_GetProvider (vlc_object_t *obj)
  85 {
  86     libvlc_priv_t *priv = libvlc_priv (obj->p_libvlc);
  87     vlc_object_t *provider;
  88
  89     vlc_mutex_lock (&provider_lock);
  90     if ((provider = priv->p_dialog_provider) != NULL)
  91         vlc_object_hold (provider);
  92     vlc_mutex_unlock (&provider_lock);
  93     return provider;
  94 }
  95
  96 /**
  97  * Sends an error message through the user interface (if any).
  98  * @param obj the VLC object emitting the error
  99  * @param modal whether to wait for user to acknowledge the error
 100  *              before returning control to the caller
 101  * @param title title of the error dialog
 102  * @param fmt format string for the error message
 103  * @param ap parameters list for the formatted error message
 104  */
 105 void dialog_VFatal (vlc_object_t *obj, bool modal, const char *title,
 106                     const char *fmt, va_list ap)
 107 {
 108     char *text;
 109
 110     if (obj->i_flags & OBJECT_FLAGS_NOINTERACT)
 111         return;
 112
 113     vlc_object_t *provider = dialog_GetProvider (obj);
 114     if (provider == NULL)
 115     {
 116         msg_Err (obj, "%s", title);
 117         msg_GenericVa (obj, VLC_MSG_ERR, MODULE_STRING, fmt, ap);
 118         return;
 119     }
 120
 121     if (vasprintf (&text, fmt, ap) != -1)
 122     {
 123         dialog_fatal_t dialog = { title, text, };
 124         var_SetAddress (provider,
 125                         modal ? "dialog-critical" : "dialog-error", &dialog);
 126         free (text);
 127     }
 128     vlc_object_release (provider);
 129 }
 130
 131 #undef dialog_Login
 132 /**
 133  * Requests a username and password through the user interface.
 134  * @param obj the VLC object requesting credential information
 135  * @param username a pointer to the specified username [OUT]
 136  * @param password a pointer to the specified password [OUT]
 137  * @param title title for the dialog
 138  * @param text format string for the message in the dialog
 139  * @return Nothing. If a user name resp. a password was specified,
 140  * it will be returned as a heap-allocated character array
 141  * into the username resp password pointer. Those must be freed with free().
 142  * Otherwise *username resp *password will be NULL.
 143  */
 144 void dialog_Login (vlc_object_t *obj, char **username, char **password,
 145                    const char *title, const char *fmt, ...)
 146 {
 147     assert ((username != NULL) && (password != NULL));
 148
 149     *username = *password = NULL;
 150     if (obj->i_flags & OBJECT_FLAGS_NOINTERACT)
 151         return;
 152
 153     vlc_object_t *provider = dialog_GetProvider (obj);
 154     if (provider == NULL)
 155         return;
 156
 157     char *text;
 158     va_list ap;
 159
 160     va_start (ap, fmt);
 161     if (vasprintf (&text, fmt, ap) != -1)
 162     {
 163         dialog_login_t dialog = { title, text, username, password, };
 164         var_SetAddress (provider, "dialog-login", &dialog);
 165         free (text);
 166     }
 167     va_end (ap);
 168     vlc_object_release (provider);
 169 }
 170
 171
 172 #undef dialog_Question
 173 /**
 174  * Asks a total (Yes/No/Cancel) question through the user interface.
 175  * @param obj VLC object emitting the question
 176  * @param title dialog box title
 177  * @param text dialog box text
 178  * @param yes first choice/button text
 179  * @param no second choice/button text
 180  * @param cancel third answer/button text, or NULL if no third option
 181  * @return 0 if the user could not answer the question (e.g. there is no UI),
 182  * 1, 2 resp. 3 if the user pressed the first, second resp. third button.
 183  */
 184 int dialog_Question (vlc_object_t *obj, const char *title, const char *text,
 185                      const char *yes, const char *no, const char *cancel)
 186 {
 187     if (obj->i_flags & OBJECT_FLAGS_NOINTERACT)
 188         return 0;
 189
 190     vlc_object_t *provider = dialog_GetProvider (obj);
 191     if (provider == NULL)
 192         return 0;
 193
 194     dialog_question_t dialog = { title, text, yes, no, cancel, 0, };
 195     var_SetAddress (provider, "dialog-question", &dialog);
 196     vlc_object_release (provider);
 197     return dialog.answer;
 198 }
 199
 200 #undef dialog_ProgressCreate
 201 /**
 202  * Creates a progress bar dialog.
 203  */
 204 dialog_progress_bar_t *
 205 dialog_ProgressCreate (vlc_object_t *obj, const char *title,
 206                        const char *message, const char *cancel)
 207 {
 208     if (obj->i_flags & OBJECT_FLAGS_NOINTERACT)
 209         return NULL;
 210
 211     vlc_object_t *provider = dialog_GetProvider (obj);
 212     if (provider == NULL)
 213         return NULL;
 214
 215     dialog_progress_bar_t *dialog = malloc (sizeof (*dialog));
 216     if (dialog != NULL)
 217     {
 218         dialog->title = title;
 219         dialog->message = message;
 220         dialog->cancel = cancel;
 221         var_SetAddress (provider, "dialog-progress-bar", dialog);
 222 #ifndef NDEBUG
 223         dialog->title = dialog->message = dialog->cancel = NULL;
 224 #endif
 225         assert (dialog->pf_update);
 226         assert (dialog->pf_check);
 227         assert (dialog->pf_destroy);
 228     }
 229
 230     /* FIXME: This could conceivably crash if the dialog provider is destroyed
 231      * before the dialog user. Holding the provider does not help, as it only
 232      * protects object variable operations. For instance, it does not prevent
 233      * unloading of the interface plugin. In the short term, the only solution
 234      * is to not use progress dialog after deinitialization of the interfaces.
 235      */
 236     vlc_object_release (provider);
 237     return dialog;
 238 }
 239
 240 void dialog_ProgressDestroy (dialog_progress_bar_t *dialog)
 241 {
 242     assert (dialog);
 243
 244     dialog->pf_destroy (dialog->p_sys);
 245     free (dialog);
 246 }
 247
 248 void dialog_ProgressSet (dialog_progress_bar_t *dialog, const char *text,
 249                          float value)
 250 {
 251     assert (dialog);
 252
 253     dialog->pf_update (dialog->p_sys, text, value);
 254 }
 255
 256 bool dialog_ProgressCancelled (dialog_progress_bar_t *dialog)
 257 {
 258     assert (dialog);
 259
 260     return dialog->pf_check (dialog->p_sys);
 261 }
 262
 263 #undef dialog_ExtensionUpdate
 264 int dialog_ExtensionUpdate (vlc_object_t *obj, extension_dialog_t *dialog)
 265 {
 266     assert (obj);
 267     assert (dialog);
 268
 269     vlc_object_t *dp = dialog_GetProvider(obj);
 270     if (!dp)
 271     {
 272         msg_Warn (obj, "Dialog provider is not set, can't update dialog '%s'",
 273                   dialog->psz_title);
 274         return VLC_EGENERIC;
 275     }
 276
 277     // Signaling the dialog provider
 278     int ret = var_SetAddress (dp, "dialog-extension", dialog);
 279
 280     vlc_object_release (dp);
 281     return ret;
 282 }