zephyr/zwgc/display.c

   1 /* This file is part of the Project Athena Zephyr Notification System.
   2  * It is one of the source files comprising zwgc, the Zephyr WindowGram
   3  * client.
   4  *
   5  *      Created by:     Marc Horowitz <marc@athena.mit.edu>
   6  *
   7  *      $Id: display.c,v 1.4 1999/01/22 23:20:15 ghudson Exp $
   8  *
   9  *      Copyright (c) 1989 by the Massachusetts Institute of Technology.
  10  *      For copying and distribution information, see the file
  11  *      "mit-copyright.h".
  12  */
  13
  14 #if (!defined(lint) && !defined(SABER))
  15 static char rcsid_display_c[] = "$Id: display.c,v 1.4 1999/01/22 23:20:15 ghudson Exp $";
  16 #endif
  17
  18 #include <zephyr/mit-copyright.h>
  19
  20 /****************************************************************************/
  21 /*                                                                          */
  22 /*             "Bus" module for plug in output driver modules:              */
  23 /*                                                                          */
  24 /****************************************************************************/
  25
  26 #include <sysdep.h>
  27 #include "new_memory.h"
  28 #include "new_string.h"
  29 #include "variables.h"
  30 #include "display.h"
  31
  32 /*
  33  * driver_table - <<<>>>
  34  */
  35
  36 extern void tty_driver();
  37 extern void plain_driver();
  38 extern void raw_driver();
  39
  40 extern int tty_driver_init();
  41
  42 #ifndef X_DISPLAY_MISSING
  43 extern int X_driver_init();
  44 extern void X_driver();
  45 #endif
  46
  47 static struct driver_info {
  48     string driver_name;
  49     void   (*driver)();
  50     int    (*driver_init)();
  51     void   (*driver_reset)();
  52 } driver_table[] = {
  53 #ifndef X_DISPLAY_MISSING
  54     {"X",     X_driver,     X_driver_init,   X_driver_reset},
  55 #endif
  56     {"tty",   tty_driver,   tty_driver_init, NULL},
  57     {"plain", plain_driver, NULL,            NULL},
  58     {"raw",   raw_driver,   NULL,            NULL},
  59     {NULL,    NULL,         NULL,            NULL}
  60 };
  61
  62 /*
  63  * <<<>>>
  64  */
  65
  66 struct driver_info *get_driver_info(driver_name)
  67      string driver_name;
  68 {
  69     struct driver_info *d;
  70
  71     for (d=driver_table; d->driver_name; d++)
  72       if (string_Eq(d->driver_name, driver_name) && d->driver)
  73         return(d);
  74
  75     return(NULL);
  76 }
  77
  78 /*
  79  *    void init_display(int *pargc; char **argv)
  80  *        Effects: <<<>>>
  81  */
  82
  83 void display_init(pargc, argv)
  84      int *pargc;
  85      char **argv;
  86 {
  87     char **new, **current;
  88     struct driver_info *d;
  89     string first_working_driver = "";
  90     string default_driver = "";
  91
  92     /*
  93      * Process argument list handling "-disable <driver>" and
  94      * "-default <driver>" arguments:
  95      */
  96     for (new=current=argv+1; *current; current++) {
  97         if (string_Eq(*current, "-disable")) {
  98             current++; *pargc -= 2;
  99             if (!*current)
 100               usage();
 101             if (d = get_driver_info(*current))
 102               d->driver = NULL;
 103         } else if (string_Eq(*current, "-default")) {
 104             current++; *pargc -= 2;
 105             if (!*current)
 106               usage();
 107             default_driver = *current;
 108         } else
 109           *(new++) = *current;
 110     }
 111     *new = *current;
 112
 113     /*
 114      * Initialize all non-disabled drivers.  If a driver reports an error,
 115      * disable that driver.  Set default_driver if not already set
 116      * by the -default argument to the first non-disabled driver.
 117      */
 118     for (d = driver_table; d->driver_name; d++) {
 119         if (!d->driver)
 120           continue;
 121
 122         if (d->driver_init && d->driver_init(pargc, argv)) {
 123             d->driver = NULL;
 124             continue;
 125         }
 126
 127         if (!*first_working_driver)
 128           first_working_driver = d->driver_name;
 129     }
 130
 131     if (!get_driver_info(default_driver))
 132       default_driver = first_working_driver;
 133
 134     var_set_variable("output_driver", default_driver);
 135 }
 136
 137 void display_reset()
 138 {
 139    for (d = driver_table; d->driver_name; d++)
 140       if (d->driver) d->driver_reset();
 141 }