send.h

   1 /** \file send.h sender-related defines and structures */
   2 /** the sender subcommands */
   3 enum {SENDER_ADD, SENDER_DELETE, SENDER_ALLOW, SENDER_DENY, SENDER_ON, SENDER_OFF};
   4
   5 /** the number of sender subcommands */
   6 #define NUM_SENDER_CMDS (SENDER_OFF + 1)
   7
   8 /**
   9  * describes one supported sender of para_server
  10  *
  11  * \sa http_send.c ortp_send.c
  12  */
  13 struct sender {
  14 /** the name of the sender */
  15         const char *name;
  16 /**
  17  * the init function of this sender
  18  *
  19  * It must fill in all function pointers of \a s as well as the \a client_cmds
  20  * array, see below. It should also do all necessary preparations to init
  21  * this sending facility, for example it could open a tcp port.
  22  */
  23         void (*init)(struct sender *s);
  24 /** \p SENDER_ON or \p SENDER_OFF */
  25         int status;
  26 /**
  27  * return the help text of this sender
  28  *
  29  * The result must be dynamically allocated and is freed by the caller.
  30  */
  31         char* (*help)(void);
  32 /**
  33  * return current status info about this sender
  34  *
  35  * The result must be dynamically allocated and is freed by the caller.
  36  */
  37         char* (*info)(void);
  38 /**
  39  * the send-hook
  40  *
  41  * It gets called whenever para_server is playing and the current
  42  * audio format handler indicates that another chunk of data should
  43  * be sent now. The two parameters \a current_chunk and \a chunks_sent
  44  * only differ if the stream was repositioned by the \a ff or \a jmp
  45  * command. Of course, \a buf is a pointer to the chunk of data which
  46  * should be sent, and \a len is the length of this buffer.
  47 */
  48         void (*send)(long unsigned current_chunk, long unsigned chunks_sent,
  49                 const char *buf, size_t len);
  50 /** add file descriptors to fd_sets
  51  *
  52  * The pre_select function of each supported sender is called just before
  53  * para_server enters its main select loop. Each sender may add its own
  54  * file descriptors to the \a rfds or the \a wfds set.
  55  *
  56  * If a file descriptor was added, \a max_fileno must be increased by
  57  * this function, if necessary.
  58  *
  59  * \sa select(2)
  60 */
  61         void (*pre_select)(int *max_fileno, fd_set *rfds, fd_set *wfds);
  62 /**
  63  * handle the file descriptors which are ready for I/O
  64  *
  65  * If the pre_select hook added one ore more file descriptors to the read or write
  66  * set, this is the hook to check the result and do any I/O on those descriptors
  67  * which are ready for reading/writing.
  68  */
  69         void (*post_select)(fd_set *rfds, fd_set *wfds);
  70 /**
  71  * terminate all connected clients
  72  *
  73  * This is called e.g. if the stop command was executed. It should make the clients
  74  * aware of the end-of-file condition.
  75  */
  76         void (*shutdown_clients)(void);
  77 /**
  78  * array of function pointers for the sender subcommands
  79  *
  80  * Each sender may implement any subset of the sender commands by filling in
  81  * the appropriate function pointer in the array. A \p NULL pointer means this
  82  * command is not implemented by this sender.
  83  */
  84         int (*client_cmds[NUM_SENDER_CMDS])(struct sender_command_data*);
  85 };
  86