src/terminal/itrm.h

   1 #ifndef EL__TERMINAL_ITRM_H
   2 #define EL__TERMINAL_ITRM_H
   3
   4
   5 #define ITRM_OUT_QUEUE_SIZE     16384
   6
   7 /* Currently, ELinks treats control sequences as text if they are
   8  * longer than ITRM_IN_QUEUE_SIZE bytes.  So it should be defined
   9  * as greater than the length of any control sequence that ELinks
  10  * is expected to receive.  These are the longest so far:
  11  * VT420: "\E[?64;1;2;6;7;8;9;15;18;19;21c"
  12  * VT510: "\E[?64;1;2;7;8;9;12;15;18;21;23;24;42;44;45;46c" */
  13 #define ITRM_IN_QUEUE_SIZE      64
  14
  15 struct itrm_queue {
  16         unsigned char *data;
  17
  18         /* The amount of data in the queue, in bytes.  This may be
  19          * less than the amount of memory allocated for the buffer;
  20          * struct itrm_queue does not keep track of that, and has
  21          * no global policy on whether the buffer can be resized.  */
  22         int len;
  23 };
  24
  25 /* Things coming into an itrm, whether from the terminal or from the
  26  * master.  */
  27 struct itrm_in {
  28         /* A file descriptor for the standard input.  In some ports,
  29          * this is the terminal device itself; in others, this is a
  30          * pipe from an input thread.  In principle, the data format
  31          * depends on the terminal.  */
  32         int std;
  33
  34         /* In a slave process, a file descriptor for a socket from
  35          * which it reads data sent by the master process.  The other
  36          * end of the socket connection is terminal.fdout in the
  37          * master process.  The format of these data is almost the
  38          * same as could be sent to the terminal (via itrm.out.std),
  39          * but there are special commands that begin with a null byte.
  40          *
  41          * In the master process, @sock is the same as itrm.out.std,
  42          * but nothing actually uses it.  */
  43         int sock;
  44
  45         /* A file descriptor for controlling the standard input.  This
  46          * is always the terminal device itself, thus the same as @std
  47          * in some ports.  ELinks doesn't read or write with this file
  48          * descriptor; it only does things like tcsetattr.  */
  49         int ctl;
  50
  51         /* Bytes that have been received from @std but not yet
  52          * converted to events.  queue.data is allocated for
  53          * ITRM_IN_QUEUE_SIZE bytes and never resized.  The itrm
  54          * layer cannot parse control sequences longer than that.
  55          * Anything that modifies queue.len should also call
  56          * unhandle_itrm_stdin() if the queue becomes full, or
  57          * handle_itrm_stdin() if the queue stops being full.
  58          * Those functions are internal to kbd.c.  */
  59         struct itrm_queue queue;
  60 };
  61
  62 /* Things going out from an itrm, whether to the terminal or to the
  63  * master.  */
  64 struct itrm_out {
  65         /* A file descriptor for the standard output.  In some ports,
  66          * this is the terminal device itself; in others, this is a
  67          * pipe to an output thread.  The data format depends on the
  68          * terminal in principle, but this has not yet been
  69          * implemented; see bug 96.  */
  70         int std;
  71
  72         /* A file descriptor for a pipe or socket to which this
  73          * process sends input events.  The other end of the pipe or
  74          * socket connection is terminal.fdin in the master process.
  75          * If the connection is from the master process to itself, it
  76          * uses a pipe; otherwise a socket.  The events are formatted
  77          * as struct interlink_event, but at the beginning of the
  78          * connection, a struct terminal_info and extra data are also
  79          * sent.  */
  80         int sock;
  81
  82         /* Bytes that should be written to @sock.  They will be
  83          * written when select() indicates the write won't block.  To
  84          * add data here, call itrm_queue_event(), which reallocates
  85          * queue.data if appropriate.  The size of this queue is
  86          * unrelated to ITRM_OUT_QUEUE_SIZE.  */
  87         struct itrm_queue queue;
  88 };
  89
  90 /* A connection between a terminal and a master ELinks process.
  91  * Normally, only one struct itrm exists in each master or slave
  92  * process, and the global pointer @ditrm (not declared here)
  93  * points to it.  */
  94 struct itrm {
  95         struct itrm_in in;              /* Input */
  96         struct itrm_out out;            /* Output */
  97
  98         timer_id_T timer;               /* ESC timeout timer */
  99         struct termios t;               /* For restoring original attributes */
 100         void *mouse_h;                  /* Mouse handle */
 101         unsigned char *orig_title;      /* For restoring window title */
 102
 103         unsigned int blocked:1;         /* Whether it was blocked */
 104         unsigned int altscreen:1;       /* Whether to use alternate screen */
 105         unsigned int touched_title:1;   /* Whether the term title was changed */
 106         /* The @remote flag is not set in regular slave terminals.
 107          * Instead, it means the itrm controls a preexisting terminal,
 108          * and windows should not be displayed on the terminal of the
 109          * itrm (but see bug 776: the master clears the terminal anyway);
 110          * thus the terminal init and done strings are not sent.  */
 111         unsigned int remote:1;          /* Whether it is a remote session */
 112 };
 113
 114 #endif