playlist.c

编译后直接运行的ＭＰ３播放器全部Ｃ语言源代码 一个包含FAT文件系统、系统引导 Boot、FLASH Driver等内容的

            flags = PLAYLIST_INSERT_TYPE_APPEND;
            break;
    }
    
    if (queue)
        flags |= PLAYLIST_QUEUED;

    /* shift indices so that track can be added */
    for (i=playlist->amount; i>insert_position; i--)
        playlist->indices[i] = playlist->indices[i-1];

    /* update stored indices if needed */
    if (playlist->amount > 0 && insert_position <= playlist->index)
        playlist->index++;

    if (playlist->amount > 0 && insert_position <= playlist->first_index &&
        position != PLAYLIST_PREPEND)
    {
        playlist->first_index++;

        if (seek_pos < 0 && playlist->current)
        {
            global_settings.resume_first_index = playlist->first_index;
            settings_save();
        }
    }

    if (insert_position < playlist->last_insert_pos ||
        (insert_position == playlist->last_insert_pos && position < 0))
        playlist->last_insert_pos++;

    if (seek_pos < 0 && playlist->control_fd >= 0)
    {
        int result = -1;

        if (flush_pending_control(playlist) < 0)
            return -1;

        mutex_lock(&playlist->control_mutex);

        if (lseek(playlist->control_fd, 0, SEEK_END) >= 0)
        {
            if (fprintf(playlist->control_fd, "%c:%d:%d:", (queue?'Q':'A'),
                    position, playlist->last_insert_pos) > 0)
            {
                /* save the position in file where track name is written */
                seek_pos = lseek(playlist->control_fd, 0, SEEK_CUR);

                if (fprintf(playlist->control_fd, "%s\n", filename) > 0)
                    result = 0;
            }
        }

        mutex_unlock(&playlist->control_mutex);

        if (result < 0)
        {
            splash(HZ*2, true, str(LANG_PLAYLIST_CONTROL_UPDATE_ERROR));
            return result;
        }
    }

    playlist->indices[insert_position] = flags | seek_pos;

    playlist->amount++;
    playlist->num_inserted_tracks++;

    return insert_position;
}

/*
 * Insert directory into playlist.  May be called recursively.
 */
static int add_directory_to_playlist(struct playlist_info* playlist,
                                     char *dirname, int *position, bool queue,
                                     int *count, bool recurse)
{
    char buf[MAX_PATH+1];
    char *count_str;
    int result = 0;
    int num_files = 0;
    bool buffer_full = false;
    int i;
    int dirfilter = SHOW_ALL;
    struct entry *files;

    /* use the tree browser dircache to load files */
    files = load_and_sort_directory(dirname, &dirfilter, &num_files,
        &buffer_full);

    if(!files)
    {
        splash(HZ*2, true, str(LANG_PLAYLIST_DIRECTORY_ACCESS_ERROR));
        return 0;
    }

    /* we've overwritten the dircache so tree browser will need to be
       reloaded */
    reload_directory();

    if (queue)
        count_str = str(LANG_PLAYLIST_QUEUE_COUNT);
    else
        count_str = str(LANG_PLAYLIST_INSERT_COUNT);

    for (i=0; i<num_files; i++)
    {
        /* user abort */
#if defined(HAVE_PLAYER_KEYPAD) || defined(HAVE_NEO_KEYPAD)
        if (button_get(false) == BUTTON_STOP)
#else
        if (button_get(false) == BUTTON_OFF)
#endif
        {
            result = -1;
            break;
        }

        if (files[i].attr & ATTR_DIRECTORY)
        {
            if (recurse)
            {
                /* recursively add directories */
                snprintf(buf, sizeof(buf), "%s/%s", dirname, files[i].name);
                result = add_directory_to_playlist(playlist, buf, position,
                    queue, count, recurse);
                if (result < 0)
                    break;

                /* we now need to reload our current directory */
                files = load_and_sort_directory(dirname, &dirfilter, &num_files,
                    &buffer_full);
                if (!files)
                {
                    result = -1;
                    break;
                }
            }
            else
                continue;
        }
        else if ((files[i].attr & TREE_ATTR_MASK) == TREE_ATTR_MPA)
        {
            int insert_pos;

            snprintf(buf, sizeof(buf), "%s/%s", dirname, files[i].name);
            
            insert_pos = add_track_to_playlist(playlist, buf, *position,
                queue, -1);
            if (insert_pos < 0)
            {
                result = -1;
                break;
            }

            (*count)++;

            /* Make sure tracks are inserted in correct order if user requests
               INSERT_FIRST */
            if (*position == PLAYLIST_INSERT_FIRST || *position >= 0)
                *position = insert_pos + 1;

            if ((*count%PLAYLIST_DISPLAY_COUNT) == 0)
            {
                display_playlist_count(*count, count_str);

                if (*count == PLAYLIST_DISPLAY_COUNT)
                    mpeg_flush_and_reload_tracks();
            }
            
            /* let the other threads work */
            yield();
        }
    }

    return result;
}

/*
 * remove track at specified position
 */
static int remove_track_from_playlist(struct playlist_info* playlist,
                                      int position, bool write)
{
    int i;
    bool inserted;

    if (playlist->amount <= 0)
        return -1;

    inserted = playlist->indices[position] & PLAYLIST_INSERT_TYPE_MASK;

    /* shift indices now that track has been removed */
    for (i=position; i<playlist->amount; i++)
        playlist->indices[i] = playlist->indices[i+1];

    playlist->amount--;

    if (inserted)
        playlist->num_inserted_tracks--;
    else
        playlist->deleted = true;

    /* update stored indices if needed */
    if (position < playlist->index)
        playlist->index--;

    if (position < playlist->first_index)
    {
        playlist->first_index--;

        if (write)
        {
            global_settings.resume_first_index = playlist->first_index;
            settings_save();
        }
    }

    if (position <= playlist->last_insert_pos)
        playlist->last_insert_pos--;

    if (write && playlist->control_fd >= 0)
    {
        int result = -1;

        if (flush_pending_control(playlist) < 0)
            return -1;

        mutex_lock(&playlist->control_mutex);

        if (lseek(playlist->control_fd, 0, SEEK_END) >= 0)
        {
            if (fprintf(playlist->control_fd, "D:%d\n", position) > 0)
            {
                fsync(playlist->control_fd);
                result = 0;
            }
        }

        mutex_unlock(&playlist->control_mutex);

        if (result < 0)
        {
            splash(HZ*2, true, str(LANG_PLAYLIST_CONTROL_UPDATE_ERROR));
            return result;
        }
    }

    return 0;
}

/*
 * randomly rearrange the array of indices for the playlist.  If start_current
 * is true then update the index to the new index of the current playing track
 */
static int randomise_playlist(struct playlist_info* playlist,
                              unsigned int seed, bool start_current,
                              bool write)
{
    int count;
    int candidate;
    int store;
    unsigned int current = playlist->indices[playlist->index];
    
    /* seed 0 is used to identify sorted playlist for resume purposes */
    if (seed == 0)
        seed = 1;

    /* seed with the given seed */
    srand(seed);

    /* randomise entire indices list */
    for(count = playlist->amount - 1; count >= 0; count--)
    {
        /* the rand is from 0 to RAND_MAX, so adjust to our value range */
        candidate = rand() % (count + 1);

        /* now swap the values at the 'count' and 'candidate' positions */
        store = playlist->indices[candidate];
        playlist->indices[candidate] = playlist->indices[count];
        playlist->indices[count] = store;
    }

    if (start_current)
        find_and_set_playlist_index(playlist, current);

    /* indices have been moved so last insert position is no longer valid */
    playlist->last_insert_pos = -1;

    playlist->seed = seed;
    if (playlist->num_inserted_tracks > 0 || playlist->deleted)
        playlist->shuffle_modified = true;

    if (write)
    {
        /* Don't write to disk immediately.  Instead, save in settings and
           only flush if playlist is modified (insertion/deletion) */
        playlist->shuffle_flush = true;
        global_settings.resume_seed = seed;
        settings_save();
    }

    return 0;
}

/*
 * Sort the array of indices for the playlist. If start_current is true then
 * set the index to the new index of the current song.
 */
static int sort_playlist(struct playlist_info* playlist, bool start_current,
                         bool write)
{
    unsigned int current = playlist->indices[playlist->index];

    if (playlist->amount > 0)
        qsort(playlist->indices, playlist->amount, sizeof(playlist->indices[0]),
            compare);

    if (start_current)
        find_and_set_playlist_index(playlist, current);

    /* indices have been moved so last insert position is no longer valid */
    playlist->last_insert_pos = -1;

    if (!playlist->num_inserted_tracks && !playlist->deleted)
        playlist->shuffle_modified = false;
    if (write && playlist->control_fd >= 0)
    {
        /* Don't write to disk immediately.  Instead, save in settings and
           only flush if playlist is modified (insertion/deletion) */
        playlist->shuffle_flush = true;
        global_settings.resume_seed = 0;
        settings_save();
    }

    return 0;
}

/*
 * returns the index of the track that is "steps" away from current playing
 * track.
 */
static int get_next_index(struct playlist_info* playlist, int steps)
{
    int current_index = playlist->index;
    int next_index    = -1;

    if (playlist->amount <= 0)
        return -1;

    switch (global_settings.repeat_mode)
    {
        case REPEAT_OFF:
        {
            current_index = rotate_index(playlist, current_index);
            
            next_index = current_index+steps;
            if ((next_index < 0) || (next_index >= playlist->amount))
                next_index = -1;
            else
                next_index = (next_index+playlist->first_index) %
                    playlist->amount;

            break;
        }

        case REPEAT_ONE:
            next_index = current_index;
            break;

        case REPEAT_ALL:
        default:
        {
            next_index = (current_index+steps) % playlist->amount;
            while (next_index < 0)
                next_index += playlist->amount;

            if (steps >= playlist->amount)
            {
                int i, index;

                index = next_index;
                next_index = -1;

                /* second time around so skip the queued files */
                for (i=0; i<playlist->amount; i++)
                {
                    if (playlist->indices[index] & PLAYLIST_QUEUE_MASK)
                        index = (index+1) % playlist->amount;
                    else
                    {
                        next_index = index;
                        break;
                    }
                }
            }
            break;
        }
    }

    return next_index;
}

/*
 * Search for the seek track and set appropriate indices.  Used after shuffle
 * to make sure the current index is still pointing to correct track.
 */
static void find_and_set_playlist_index(struct playlist_info* playlist,
                                        unsigned int seek)
{
    int i;
    
    /* Set the index to the current song */
    for (i=0; i<playlist->amount; i++)
    {
        if (playlist->indices[i] == seek)
        {
            playlist->index = playlist->first_index = i;

            if (playlist->current)
            {
                global_settings.resume_first_index = i;
                settings_save();
            }

            break;
        }
    }
}

/*
 * used to sort track indices.  Sort order is as follows:
 * 1. Prepended tracks (in prepend order)
 * 2. Playlist/directory tracks (in playlist order)
 * 3. Inserted/Appended tracks (in insert order)
 */
static int compare(const void* p1, const void* p2)
{
    unsigned int* e1 = (unsigned int*) p1;
    unsigned int* e2 = (unsigned int*) p2;
    unsigned int flags1 = *e1 & PLAYLIST_INSERT_TYPE_MASK;
    unsigned int flags2 = *e2 & PLAYLIST_INSERT_TYPE_MASK;

    if (flags1 == flags2)