git.squeep.com Git - dcpu16/blob - hw_keyboard.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include <errno.h>
   4
   5 #include "dcpu16.h"
   6 #include "hw_keyboard.h"
   7
   8 #define BUF_SZ 32
   9
  10 static dcpu16_hw_signal_t keyboard_reset_;
  11 static dcpu16_hw_signal_t keyboard_cycle_;
  12 static dcpu16_hw_signal_t keyboard_hwi_;
  13 static struct dcpu16_hw hw_ = {
  14     .name_  = "Generic Keyboard (compatible)",
  15     .id_l   = 0x7406,
  16     .id_h   = 0x30cf,
  17     .ver    = 0x0001,
  18     .mfg_l  = 0x0000,
  19     .mfg_h  = 0x0000,
  20     .hwi    = keyboard_hwi_,
  21     .cycle  = keyboard_cycle_,
  22     .reset  = keyboard_reset_,
  23     .data   = (struct keyboard_ *)NULL
  24 };
  25
  26 struct keyboard_ {
  27     char *buf;
  28     size_t buf_sz;
  29     DCPU16_WORD interrupt_message;
  30 };
  31
  32 static
  33 void keyboard_reset_(struct dcpu16 *vm, void *data) {
  34     struct keyboard_ *keyboard = (struct keyboard_ *)data;
  35
  36     (void)vm;
  37
  38     keyboard->interrupt_message = 0;
  39     memset(keyboard->buf, 0, keyboard->buf_sz);
  40 }
  41
  42 static
  43 void keyboard_cycle_(struct dcpu16 *vm, void *data) {
  44     struct keyboard_ *keyboard = (struct keyboard_ *)data;
  45
  46     (void)vm, (void)keyboard;
  47 }
  48
  49 static
  50 void keyboard_hwi_(struct dcpu16 *vm, void *data) {
  51     struct keyboard_ *keyboard = (struct keyboard_ *)data;
  52     DCPU16_WORD reg_a = vm->reg[DCPU16_REG_A];
  53     DCPU16_WORD reg_b = vm->reg[DCPU16_REG_B];
  54     size_t i;
  55
  56     switch (reg_a) {
  57         case 0: /* clear keyboard buffer */
  58             memset(keyboard->buf, 0, keyboard->buf_sz);
  59             break;
  60
  61         case 1: /* get next key from buffer as C */
  62             vm->reg[DCPU16_REG_C] = keyboard->buf[0];
  63             for (i = 1; i < keyboard->buf_sz; i++) {
  64                 keyboard->buf[i-1] = keyboard->buf[i];
  65             }
  66             keyboard->buf[i] = '\0';
  67             break;
  68
  69         case 2: /* get currently-pressed-state of key in B as C */
  70             vm->warn_cb_("IMPLEMENT");
  71             (void)reg_b;
  72             vm->reg[DCPU16_REG_C] = 0;
  73             break;
  74
  75         case 3: /* set interrupt state */
  76             keyboard->interrupt_message = reg_b;
  77             break;
  78
  79     }
  80 }
  81
  82 struct dcpu16_hw *keyboard_new(struct dcpu16 *vm) {
  83     struct dcpu16_hw *hw;
  84     char *b;
  85
  86     hw = calloc(1, sizeof *hw);
  87     if (hw == NULL) {
  88         vm->warn_cb_("%s():%s", "calloc", strerror(errno));
  89         return NULL;
  90     }
  91     memcpy(hw, &hw_, sizeof *hw);
  92     hw->data = calloc(1, sizeof hw->data);
  93     if (hw->data == NULL) {
  94         vm->warn_cb_("%s():%s", "calloc", strerror(errno));
  95         free(hw);
  96         return NULL;
  97     }
  98
  99     b = calloc(BUF_SZ, sizeof *b);
 100     if (b == NULL) {
 101         vm->warn_cb_("%s():%s", "calloc", strerror(errno));
 102         free(hw->data);
 103         free(hw);
 104         return NULL;
 105     }
 106     ((struct keyboard_ *)(hw->data))->buf = b;
 107     ((struct keyboard_ *)(hw->data))->buf_sz = BUF_SZ;
 108
 109     return hw;
 110 }
 111
 112 void keyboard_del(struct dcpu16_hw **hw) {
 113     if (hw) {
 114         free(((struct keyboard_ *)((*hw)->data))->buf);
 115         ((struct keyboard_ *)((*hw)->data))->buf = NULL;
 116
 117         free((*hw)->data);
 118         (*hw)->data = NULL;
 119
 120         free(*hw);
 121         *hw = NULL;
 122     }
 123 }