Proper line discipline for TTYs and simple line discipline for chardevs

include/sys/amd64/hw/con.h

@@ -4,6 +4,9 @@ struct winsize;
 
 void amd64_con_get_size(struct winsize *ws);
 
+// For tty
+int pc_con_putc(void *dev, char c);
+
 void con_blink(void);
 void amd64_con_putc(int c);
 void amd64_con_init(void);

include/sys/amd64/hw/ps2.h

@@ -1,4 +1,6 @@
 #pragma once
+struct chrdev;
 
 void ps2_init(void);
 void ps2_register_device(void);
+void ps2_kbd_set_tty(struct chrdev *dev);

include/sys/chr.h

@@ -1,19 +1,25 @@
 #pragma once
+#include "sys/termios.h"
 #include "sys/types.h"
 #include "sys/ring.h"
 
 struct chrdev {
     void *dev_data;
+
     struct ring buffer;
+    enum {
+        CHRDEV_GENERIC = 0,
+        CHRDEV_TTY
+    } type;
+
+    // TODO: move tty info somewhere else?
+    struct termios tc;
 
     int (*ioctl) (struct chrdev *chr, unsigned int cmd, void *arg);
     ssize_t (*write) (struct chrdev *chr, const void *buf, size_t pos, size_t lim);
     ssize_t (*read) (struct chrdev *chr, void *buf, size_t pos, size_t lim);
 };
 
-// Generic ring-buffer reader
-ssize_t chr_read_ring(struct chrdev *chr, void *buf, size_t pos, size_t lim);
-
 int chr_ioctl(struct chrdev *chr, unsigned int cmd, void *arg);
 ssize_t chr_write(struct chrdev *chr, const void *buf, size_t pos, size_t lim);
 ssize_t chr_read(struct chrdev *chr, void *buf, size_t pos, size_t lim);

include/sys/line.h

@@ -0,0 +1,12 @@
+#pragma once
+struct chrdev;
+
+// Common TTY line discipline
+ssize_t line_read(struct chrdev *chr, void *buf, size_t pos, size_t lim);
+
+// Simple line discipline - no control, disregard termios, spit out data right after
+// a single byte is available
+ssize_t simple_line_read(struct chrdev *chr, void *buf, size_t pos, size_t lim);
+
+// TODO: invent some magic for devices like /dev/urandom and /dev/zero etc.
+//       they're implemented as block devices right now

include/sys/ring.h

@@ -2,19 +2,24 @@
 #include "sys/types.h"
 #include "sys/spin.h"
 
+struct thread;
+
+#define RING_SIGNAL_BRK     (1 << 0)
+#define RING_SIGNAL_EOF     (1 << 1)
+
 // Ring buffer
 struct ring {
-    char *data;
-    size_t wrptr;
-    size_t rdptr;
+    size_t rd, wr;
     size_t cap;
-    spin_t lock;
-    int post;
-    struct thread *listener;
+    char *base;
+    int flags;
 };
 
-void ring_post(struct ring *b);
-size_t ring_avail(struct ring *b);
-ssize_t ring_read(struct thread *ctx, struct ring *b, void *buf, size_t lim);
-int ring_putc(struct thread *ctx, struct ring *b, char c);
-void ring_init(struct ring *b, size_t cap);
+int ring_readable(struct ring *b);
+int ring_getc(struct thread *ctx, struct ring *b, char *c, int err);
+
+void ring_signal(struct ring *b, int type);
+int ring_putc(struct thread *ctx, struct ring *b, char c, int wait);
+int ring_write(struct thread *ctx, struct ring *b, const void *data, size_t count, int wait);
+
+int ring_init(struct ring *b, size_t cap);

include/sys/termios.h

@@ -1,11 +1,45 @@
 #pragma once
 
+#define TCGETS          0x5401
+#define TCSETS          0x5402
 #define TIOCSPGRP       0x5410
 #define TIOCGWINSZ      0x5413
 
+// Output flags
+#define OPOST           (1 << 0)
+#define ONLCR           (1 << 2)
+#define OCRNL           (1 << 4)
+#define ONLRET          (1 << 6)
+
+// Control flags
+#define ECHO            (1 << 4)        // Echo input characters
+#define ECHOE           (1 << 5)        // if ICANON, ERASE erases prec. character,
+                                        //            WERASE erases prec. word
+#define ECHOK           (1 << 6)        // if ICANON, KILL character erases the line
+#define ECHONL          (1 << 8)        // if ICANON, echo newline (even if no ECHO)
+
+#define TERMIOS_DEFAULT \
+    { \
+        .c_iflag = 0, \
+        .c_oflag = OPOST, \
+        .c_cflag = 0, \
+        .c_lflag = ECHO | ECHONL | ECHOE | ECHOK, \
+    }
+
+typedef unsigned int tcflag_t;
+
 struct winsize {
     unsigned short ws_row;
     unsigned short ws_col;
     unsigned short ws_xpixel;
     unsigned short ws_ypixel;
 };
+
+struct termios {
+    tcflag_t c_iflag;
+    tcflag_t c_oflag;
+    tcflag_t c_cflag;
+    tcflag_t c_lflag;
+};
+
+#define TCSANOW         0

include/sys/tty.h

@@ -1,6 +1,12 @@
 #pragma once
-#include "sys/fs/node.h"
+struct chrdev;
+
+// From keyboard handlers and stuff
+void tty_control_write(struct chrdev *n, char c);
+void tty_data_write(struct chrdev *n, char c);
+
+// From code directly to the screen
+void tty_puts(struct chrdev *n, const char *s);
+void tty_putc(struct chrdev *n, char c);
 
-void tty_control_write(int n, char c);
-void tty_buffer_write(int n, char c);
 void tty_init(void);