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

        return (*e1 & PLAYLIST_SEEK_MASK) - (*e2 & PLAYLIST_SEEK_MASK);
    else if (flags1 == PLAYLIST_INSERT_TYPE_PREPEND ||
        flags2 == PLAYLIST_INSERT_TYPE_APPEND)
        return -1;
    else if (flags1 == PLAYLIST_INSERT_TYPE_APPEND ||
        flags2 == PLAYLIST_INSERT_TYPE_PREPEND)
        return 1;
    else if (flags1 && flags2)
        return (*e1 & PLAYLIST_SEEK_MASK) - (*e2 & PLAYLIST_SEEK_MASK);
    else
        return *e1 - *e2;
}

/*
 * gets pathname for track at seek index
 */
static int get_filename(struct playlist_info* playlist, int seek,
                        bool control_file, char *buf, int buf_length)
{
    int fd;
    int max = -1;
    char tmp_buf[MAX_PATH+1];
    char dir_buf[MAX_PATH+1];

    if (buf_length > MAX_PATH+1)
        buf_length = MAX_PATH+1;

    if (playlist->in_ram && !control_file)
    {
        strncpy(tmp_buf, &playlist->buffer[seek], sizeof(tmp_buf));
        tmp_buf[MAX_PATH] = '\0';
        max = strlen(tmp_buf) + 1;
    }
    else
    {
        if (control_file)
            fd = playlist->control_fd;
        else
        {
            if(-1 == playlist->fd)
                playlist->fd = open(playlist->filename, O_RDONLY);
            
            fd = playlist->fd;
        }
        
        if(-1 != fd)
        {
            if (control_file)
                mutex_lock(&playlist->control_mutex);
            
            lseek(fd, seek, SEEK_SET);
            max = read(fd, tmp_buf, buf_length);
            
            if (control_file)
                mutex_unlock(&playlist->control_mutex);            
        }

        if (max < 0)
        {
            if (control_file)
                splash(HZ*2, true,
                    str(LANG_PLAYLIST_CONTROL_ACCESS_ERROR));
            else
                splash(HZ*2, true, str(LANG_PLAYLIST_ACCESS_ERROR));

            return max;
        }
    }

    strncpy(dir_buf, playlist->filename, playlist->dirlen-1);
    dir_buf[playlist->dirlen-1] = 0;

    return (format_track_path(buf, tmp_buf, buf_length, max, dir_buf));
}

/*
 * Returns absolute path of track
 */
static int format_track_path(char *dest, char *src, int buf_length, int max,
                             char *dir)
{
    int i = 0;
    int j;
    char *temp_ptr;

    /* Zero-terminate the file name */
    while((src[i] != '\n') &&
          (src[i] != '\r') &&
          (i < max))
        i++;

    /* Now work back killing white space */
    while((src[i-1] == ' ') || 
          (src[i-1] == '\t'))
        i--;

    src[i]=0;
      
    /* replace backslashes with forward slashes */
    for ( j=0; j<i; j++ )
        if ( src[j] == '\\' )
            src[j] = '/';

    if('/' == src[0])
    {
        strncpy(dest, src, buf_length);
    }
    else
    {
        /* handle dos style drive letter */
        if (':' == src[1])
            strncpy(dest, &src[2], buf_length);
        else if ('.' == src[0] && '.' == src[1] && '/' == src[2])
        {
            /* handle relative paths */
            i=3;
            while(src[i] == '.' &&
                  src[i] == '.' &&
                  src[i] == '/')
                i += 3;
            for (j=0; j<i/3; j++) {
                temp_ptr = strrchr(dir, '/');
                if (temp_ptr)
                    *temp_ptr = '\0';
                else
                    break;
            }
            snprintf(dest, buf_length, "%s/%s", dir, &src[i]);
        }
        else if ( '.' == src[0] && '/' == src[1] ) {
            snprintf(dest, buf_length, "%s/%s", dir, &src[2]);
        }
        else {
            snprintf(dest, buf_length, "%s/%s", dir, src);
        }
    }

    return 0;
}

/*
 * Display splash message showing progress of playlist/directory insertion or
 * save.
 */
static void display_playlist_count(int count, char *fmt)
{
    lcd_clear_display();

#ifdef HAVE_LCD_BITMAP
    if(global_settings.statusbar)
        lcd_setmargins(0, STATUSBAR_HEIGHT);
    else
        lcd_setmargins(0, 0);
#endif

    splash(0, true, fmt, count,
#ifdef HAVE_PLAYER_KEYPAD
           str(LANG_STOP_ABORT)
#else
           str(LANG_OFF_ABORT)
#endif
        );
}

/*
 * Display buffer full message
 */
static void display_buffer_full(void)
{
    lcd_clear_display();
    lcd_puts(0,0,str(LANG_PLAYINDICES_PLAYLIST));
    lcd_puts(0,1,str(LANG_PLAYINDICES_BUFFER));
    lcd_update();
    sleep(HZ*2);
    lcd_clear_display();
}

/*
 * Flush any pending control commands to disk.  Called when playlist is being
 * modified.  Returns 0 on success and -1 on failure.
 */
static int flush_pending_control(struct playlist_info* playlist)
{
    int result = 0;
        
    if (playlist->shuffle_flush && global_settings.resume_seed >= 0)
    {
        /* pending shuffle */
        mutex_lock(&playlist->control_mutex);
        
        if (lseek(playlist->control_fd, 0, SEEK_END) >= 0)
        {
            if (global_settings.resume_seed == 0)
                result = fprintf(playlist->control_fd, "U:%d\n",
                    playlist->first_index);
            else
                result = fprintf(playlist->control_fd, "S:%d:%d\n",
                    global_settings.resume_seed, playlist->first_index);

            if (result > 0)
            {
                fsync(playlist->control_fd);

                playlist->shuffle_flush = false;
                global_settings.resume_seed = -1;
                settings_save();

                result = 0;
            }
            else
                result = -1;
        }
        else
            result = -1;
        
        mutex_unlock(&playlist->control_mutex);
        
        if (result < 0)
        {
            splash(HZ*2, true, str(LANG_PLAYLIST_CONTROL_UPDATE_ERROR));
            return result;
        }
    }

    return result;
}

/*
 * Rotate indices such that first_index is index 0
 */
static int rotate_index(struct playlist_info* playlist, int index)
{
    index -= playlist->first_index;
    if (index < 0)
        index += playlist->amount;

    return index;
}

/*
 * Initialize playlist entries at startup
 */
void playlist_init(void)
{
    struct playlist_info* playlist = &current_playlist;

    playlist->current = true;
    snprintf(playlist->control_filename, sizeof(playlist->control_filename),
        "%s", PLAYLIST_CONTROL_FILE);
    playlist->fd = -1;
    playlist->control_fd = -1;
    playlist->max_playlist_size = global_settings.max_files_in_playlist;
    playlist->indices = buffer_alloc(playlist->max_playlist_size * sizeof(int));
    playlist->buffer_size =
        AVERAGE_FILENAME_LENGTH * global_settings.max_files_in_dir;
    playlist->buffer = buffer_alloc(playlist->buffer_size);
    mutex_init(&playlist->control_mutex);
    empty_playlist(playlist, true);
}

/*
 * Create new playlist
 */
int playlist_create(char *dir, char *file)
{
    struct playlist_info* playlist = &current_playlist;

    new_playlist(playlist, dir, file);

    if (file)
        /* load the playlist file */
        add_indices_to_playlist(playlist, NULL, 0);

    return 0;
}

#define PLAYLIST_COMMAND_SIZE (MAX_PATH+12)

/*
 * Restore the playlist state based on control file commands.  Called to
 * resume playback after shutdown.
 */
int playlist_resume(void)
{
    struct playlist_info* playlist = &current_playlist;
    char *buffer;
    int buflen;
    int nread;
    int total_read = 0;
    bool first = true;
    bool sorted = true;

    enum {
        resume_playlist,
        resume_add,
        resume_queue,
        resume_delete,
        resume_shuffle,
        resume_unshuffle,
        resume_reset,
        resume_comment
    };

    /* use mp3 buffer for maximum load speed */
    buflen = (mp3end - mp3buf);
    buffer = mp3buf;

    empty_playlist(playlist, true);

    playlist->control_fd = open(playlist->control_filename, O_RDWR);
    if (playlist->control_fd < 0)
    {
        splash(HZ*2, true, str(LANG_PLAYLIST_CONTROL_ACCESS_ERROR));
        return -1;
    }
    playlist->control_created = true;

    /* read a small amount first to get the header */
    nread = read(playlist->control_fd, buffer,
        PLAYLIST_COMMAND_SIZE<buflen?PLAYLIST_COMMAND_SIZE:buflen);
    if(nread <= 0)
    {
        splash(HZ*2, true, str(LANG_PLAYLIST_CONTROL_ACCESS_ERROR));
        return -1;
    }

    while (1)
    {
        int result = 0;
        int count;
        int current_command = resume_comment;
        int last_newline = 0;
        int str_count = -1;
        bool newline = true;
        bool exit_loop = false;
        char *p = buffer;
        char *str1 = NULL;
        char *str2 = NULL;
        char *str3 = NULL;

        for(count=0; count<nread && !exit_loop; count++,p++)
        {
            /* Are we on a new line? */
            if((*p == '\n') || (*p == '\r'))
            {
                *p = '\0';

                /* save last_newline in case we need to load more data */
                last_newline = count;

                switch (current_command)
                {
                    case resume_playlist:
                    {
                        /* str1=version str2=dir str3=file */
                        int version;
                        
                        if (!str1)
                        {
                            result = -1;
                            exit_loop = true;
                            break;
                        }
                        
                        if (!str2)
                            str2 = "";
                        
                        if (!str3)
                            str3 = "";
                        
                        version = atoi(str1);
                        
                        if (version != PLAYLIST_CONTROL_FILE_VERSION)
                            return -1;
                        
                        update_playlist_filename(playlist, str2, str3);
                        
                        if (str3[0] != '\0')
                        {
                            /* NOTE: add_indices_to_playlist() overwrites the
                               mp3buf so we need to reload control file
                               data */
                            add_indices_to_playlist(playlist, NULL, 0);
                        }
                        else if (str2[0] != '\0')
                        {
                            playlist->in_ram = true;
                            resume_directory(str2);
                        }
                        
                        /* load the rest of the data */
                        first = false;
                        exit_loop = true;

                        break;
                    }
                    case resume_add:
                    case resume_queue:
                    {
                        /* str1=position str2=last_position str3=file */
                        int position, last_position;
                        bool queue;
                        
                        if (!str1 || !str2 || !str3)
                        {
                            result = -1;
                            exit_loop = true;
                            break;
                        }
                        
                        position = atoi(str1);
                        last_position = atoi(str2);
                        
                        queue = (current_command == resume_add)?false:true;
                        
                        /* seek position is based on str3's position in
                           buffer */
                        if (add_track_to_playlist(playlist, str3, position,
                                queue, total_read+(str3-buffer)) < 0)
                            return -1;
                        
                        playlist->last_insert_pos = last_position;

                        break;
                    }
                    case resume_delete:
                    {
                        /* str1=position */
                        int position;
                        
                        if (!str1)
                        {
                            result = -1;
                            exit_loop = true;
                            break;
                        }
                        
                        position = atoi(str1);
                        
                        if (remove_track_from_playlist(playlist, position,
                                false) < 0)
                            return -1;

                        break;
                    }