[SOLVED] CS代考计算机代写 #include “devices/kbd.h”

#include “devices/kbd.h”
#include
#include
#include
#include
#include “devices/input.h”
#include “devices/shutdown.h”
#include “threads/interrupt.h”
#include “threads/io.h”

/* Keyboard data register port. */
#define DATA_REG 0x60

/* Current state of shift keys.
True if depressed, false otherwise. */
static bool left_shift, right_shift;/* Left and right Shift keys. */
static bool left_alt, right_alt;/* Left and right Alt keys. */
static bool left_ctrl, right_ctrl;/* Left and right Ctl keys. */

/* Status of Caps Lock.
True when on, false when off. */
static bool caps_lock;

/* Number of keys pressed. */
static int64_t key_cnt;

static intr_handler_func keyboard_interrupt;

/* Initializes the keyboard. */
void
kbd_init (void)
{
intr_register_ext (0x21, keyboard_interrupt, “8042 Keyboard”);
}

/* Prints keyboard statistics. */
void
kbd_print_stats (void)
{
printf (“Keyboard: %lld keys pressed
”, key_cnt);
}
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/* Maps a set of contiguous scancodes into characters. */
struct keymap
{
uint8_t first_scancode; /* First scancode. */
const char *chars;/* chars[0] has scancode first_scancode,
chars[1] has scancode first_scancode + 1,
and so on to the end of the string. */
};

/* Keys that produce the same characters regardless of whether
the Shift keys are down.Case of letters is an exception
that we handle elsewhere.*/
static const struct keymap invariant_keymap[] =
{
{0x01, “33”}, /* Escape. */
{0x0e, “b”},
{0x0f, “tQWERTYUIOP”},
{0x1c, “r”},
{0x1e, “ASDFGHJKL”},
{0x2c, “ZXCVBNM”},
{0x37, “*”},
{0x39, ” “},
{0x53, “177”}, /* Delete. */
{0, NULL},
};

/* Characters for keys pressed without Shift, for those keys
where it matters. */
static const struct keymap unshifted_keymap[] =
{
{0x02, “1234567890-=”},
{0x1a, “[]”},
{0x27, “;’`”},
{0x2b, “\”},
{0x33, “,./”},
{0, NULL},
};

/* Characters for keys pressed with Shift, for those keys where
it matters. */
static const struct keymap shifted_keymap[] =
{
{0x02, “!@#$%^&*()_+”},
{0x1a, “{}”},
{0x27, “:”~”},
{0x2b, “|”},
{0x33, “<>?”},
{0, NULL},
};

static bool map_key (const struct keymap[], unsigned scancode, uint8_t *);

static void
keyboard_interrupt (struct intr_frame *args UNUSED)
{
/* Status of shift keys. */
bool shift = left_shift || right_shift;
bool alt = left_alt || right_alt;
bool ctrl = left_ctrl || right_ctrl;

/* Keyboard scancode. */
unsigned code;

/* False if key pressed, true if key released. */
bool release;

/* Character that corresponds to `code’. */
uint8_t c;

/* Read scancode, including second byte if prefix code. */
code = inb (DATA_REG);
if (code == 0xe0)
code = (code << 8) | inb (DATA_REG);/* Bit 0x80 distinguishes key press from key release (even if there’s a prefix). */release = (code & 0x80) != 0;code &= ~0x80u;/* Interpret key. */if (code == 0x3a) {/* Caps Lock. */if (!release)caps_lock = !caps_lock;}else if (map_key (invariant_keymap, code, &c) || (!shift && map_key (unshifted_keymap, code, &c)) || (shift && map_key (shifted_keymap, code, &c))){/* Ordinary character. */if (!release) {/* Reboot if Ctrl+Alt+Del pressed. */if (c == 0177 && ctrl && alt)shutdown_reboot ();/* Handle Ctrl, Shift. Note that Ctrl overrides Shift. */if (ctrl && c >= 0x40 && c < 0x60) {/* A is 0x41, Ctrl+A is 0x01, etc. */c -= 0x40; }else if (shift == caps_lock)c = tolower (c);/* Handle Alt by setting the high bit. This 0x80 is unrelated to the one used to distinguish key press from key release. */if (alt)c += 0x80;/* Append to keyboard buffer. */if (!input_full ()){key_cnt++;input_putc (c);}}}else{/* Maps a keycode into a shift state variable. */struct shift_key {unsigned scancode;bool *state_var;};/* Table of shift keys. */static const struct shift_key shift_keys[] = {{0x2a, &left_shift},{0x36, &right_shift},{0x38, &left_alt},{0xe038, &right_alt},{0x1d, &left_ctrl},{0xe01d, &right_ctrl},{0,NULL},};const struct shift_key *key;/* Scan the table. */for (key = shift_keys; key->scancode != 0; key++)
if (key->scancode == code)
{
*key->state_var = !release;
break;
}
}
}

/* Scans the array of keymaps K for SCANCODE.
If found, sets *C to the corresponding character and returns
true.
If not found, returns false and C is ignored. */
static bool
map_key (const struct keymap k[], unsigned scancode, uint8_t *c)
{
for (; k->first_scancode != 0; k++)
if (scancode >= k->first_scancode
&& scancode < k->first_scancode + strlen (k->chars))
{
*c = k->chars[scancode – k->first_scancode];
return true;
}

return false;
}