kernel: Move video console code

This commit introduces a video console driver to Hyra and replaces
that weird tty.c file used only for video console logic

Signed-off-by: Ian Moffett <ian@osmora.org>

3 files changed, 13 insertions, 453 deletions

diff --git a/sys/kern/kern_syslog.c b/sys/kern/kern_syslog.c
index 52bdcca..d8880a9 100644
--- a/sys/kern/kern_syslog.c
+++ b/sys/kern/kern_syslog.c
@@ -28,29 +28,23 @@
  */
 
 #include <sys/syslog.h>
-#include <sys/tty.h>
 #include <sys/machdep.h>
+#include <dev/vcons/vcons.h>
 #include <string.h>
 
-static struct tty syslog_tty;
-
-/* False if we don't log to a console */
-static bool is_conlog_init = false;
+static struct vcons_screen syslog_screen = {0};
 
 static void
 syslog_write(const char *s, size_t len)
 {
-#if defined(__SERIAL_DEBUG)
     size_t tmp_len = len;
     const char *tmp_s = s;
 
     while (tmp_len--) {
-        serial_dbgch(*tmp_s++);
-    }
+#if defined(__SERIAL_DEBUG)
+        serial_dbgch(*tmp_s);
 #endif  /* defined(__SERIAL_DEBUG) */
-
-    if (is_conlog_init) {
-        tty_write(&syslog_tty, s, len);
+        vcons_putch(&syslog_screen, *tmp_s++);
     }
 }
 
@@ -131,8 +125,13 @@ kprintf(const char *fmt, ...)
 void
 syslog_init(void)
 {
-    is_conlog_init = true;
+    struct termios termios = {0};
+
+    termios.c_oflag |= OCRNL;   /* Map CR to NL by default */
+
+    syslog_screen.bg = 0x000000;
+    syslog_screen.fg = 0x808080;
+    syslog_screen.termios = termios;
 
-    tty_set_defaults(&syslog_tty);
-    tty_attach(&syslog_tty);
+    vcons_attach(&syslog_screen);
 }
diff --git a/sys/kern/subr_tty.c b/sys/kern/subr_tty.c
deleted file mode 100644
index 43a02bb..0000000
--- a/sys/kern/subr_tty.c
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice,
- *    this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of Hyra nor the names of its
- *    contributors may be used to endorse or promote products derived from
- *    this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <sys/tty.h>
-
-/*
- * Pushes a char to the TTY
- * ring buffer.
- *
- * Call with TTY locked.
- */
-void
-tty_push_char(struct tty *tty, int c)
-{
-    struct tty_ring *ring;
-
-    ring = &tty->ring;
-
-    /*
-     * If our ring is full, it should
-     * be flushed as soon as possible.
-     *
-     * XXX: ring->len will be reset by tty_flush()
-     * so there is no need to do it here.
-     */
-    if (ring->len >= LINE_RING_SIZE) {
-        tty_flush(tty);
-    }
-
-    ring->buf[ring->len++] = c;
-}
diff --git a/sys/kern/tty.c b/sys/kern/tty.c
deleted file mode 100644
index 3a959a9..0000000
--- a/sys/kern/tty.c
+++ /dev/null
@@ -1,382 +0,0 @@
-/*
- * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice,
- *    this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of Hyra nor the names of its
- *    contributors may be used to endorse or promote products derived from
- *    this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <sys/tty.h>
-#include <sys/cdefs.h>
-#include <sys/errno.h>
-#include <sys/ascii.h>
-#include <string.h>
-#include <tty_font.h>
-
-/*
- * Default cursor color.
- *
- * TODO: The cursor color should
- *       be the invert of the color
- *       of whatever it is on top of.
- */
-#define DEFAULT_CURSOR_BG 0x808080
-
-#define CURSOR_WIDTH            FONT_WIDTH
-#define CURSOR_HEIGHT           FONT_HEIGHT
-
-__KERNEL_META("$Hyra$: tty.c, Ian Marco Moffett, "
-              "Core TTY implementation");
-
-/* List of attached TTYs */
-static TAILQ_HEAD(, tty) tty_list;
-
-/*
- * Renders a char onto the TTY specified by `tty`.
- */
-static void
-tty_draw_char(struct tty *tty, char c, uint32_t fg, uint32_t bg)
-{
-    uint32_t *fb_ptr;
-    uint32_t x, y;
-    size_t idx;
-    const uint8_t *glyph;
-
-    /* Get a pointer to framebuffer memory */
-    fb_ptr = tty->fbdev.mem;
-
-    /* Get the specific glyph of `c` */
-    glyph = &DEFAULT_FONT_DATA[(int)c*16];
-
-    x = tty->chpos_x;
-    y = tty->chpos_y;
-
-    for (uint32_t cy = 0; cy < FONT_HEIGHT; ++cy) {
-        for (uint32_t cx = 0; cx < FONT_WIDTH; ++cx) {
-            idx = fbdev_get_index(&tty->fbdev, x+FONT_WIDTH-cx, y+cy);
-            fb_ptr[idx] = __TEST(glyph[cy], __BIT(cx)) ? fg : bg;
-        }
-    }
-}
-
-/*
- * Draws a cursor onto the screen.
- *
- * Call with TTY locked.
- */
-static void
-tty_draw_cursor(struct tty *tty, bool hide)
-{
-    uint32_t x, y, idx;
-    uint32_t *fb_ptr;
-    uint32_t color;
-
-    fb_ptr = tty->fbdev.mem;
-    color = hide ? tty->bg : DEFAULT_CURSOR_BG;
-
-    for (size_t cy = 0; cy < CURSOR_HEIGHT; ++cy) {
-        for (size_t cx = 0; cx < CURSOR_WIDTH; ++cx) {
-            x = tty->curspos_x + cx;
-            y = tty->curspos_y + cy;
-            idx = fbdev_get_index(&tty->fbdev, x, y);
-            fb_ptr[idx] = color;
-        }
-    }
-}
-
-static void
-tty_scroll_single(struct tty *tty)
-{
-    uint32_t *fb_ptr;
-    size_t line_size, dest_idx, src_idx;
-
-    fb_ptr = tty->fbdev.mem;
-    line_size = tty->fbdev.pitch/4;
-
-    /* Copy each line up */
-    for (size_t y = FONT_HEIGHT; y < tty->t_ws_ypixel; y += FONT_HEIGHT) {
-        dest_idx = fbdev_get_index(&tty->fbdev, 0, y - FONT_HEIGHT);
-        src_idx = fbdev_get_index(&tty->fbdev, 0, y);
-        memcpy32(&fb_ptr[dest_idx], &fb_ptr[src_idx], FONT_HEIGHT*line_size);
-    }
-
-    /*
-     * Ensure we start at X position 0
-     * after we scrolled down.
-     */
-    tty->chpos_x = 0;
-    tty->curspos_x = 0;
-}
-
-/*
- * Handles a newline.
- *
- * Call with TTY locked.
- */
-static inline void
-tty_newline(struct tty *tty)
-{
-    uint32_t ypos;
-    const uint32_t MAX_YPOS = tty->t_ws_ypixel - (CURSOR_HEIGHT*2);
-
-    /* Hide the cursor */
-    tty_draw_cursor(tty, true);
-
-    /* Reset X positions */
-    tty->chpos_x = 0;
-    tty->curspos_x = 0;
-
-    /*
-     * Get the value closest to end
-     * of the screen.
-     */
-    ypos = __MAX(tty->chpos_y, tty->curspos_y);
-
-    /*
-     * Check if we need to scroll
-     * instead of incrementing
-     * Y positions.
-     */
-    if (ypos < MAX_YPOS) {
-        tty->chpos_y += FONT_HEIGHT;
-        tty->curspos_y += FONT_HEIGHT;
-    } else {
-        tty_scroll_single(tty);
-    }
-
-    /* Redraw the cursor */
-    tty_draw_cursor(tty, false);
-}
-
-/*
- * Appends a character to the TTY specified
- * by `tty` as well as incrementing tty->chpos_x
- * and making newlines as needed.
- *
- * Call with TTY locked.
- */
-static inline void
-tty_append_char(struct tty *tty, int c)
-{
-    const uint32_t MAX_XPOS = tty->t_ws_xpixel - FONT_WIDTH;
-
-    /* Hide the cursor */
-    tty_draw_cursor(tty, true);
-
-    tty_draw_char(tty, c, tty->fg, tty->bg);
-    tty->chpos_x += FONT_WIDTH;
-    tty->curspos_x += FONT_WIDTH;
-
-    if (tty->chpos_x >= MAX_XPOS) {
-        tty_newline(tty);
-    }
-
-    /* Redraw the cursor */
-    tty_draw_cursor(tty, false);
-}
-
-/*
- * Writes out a tab as `tty->tab_width`
- * spaces.
- *
- * Call with TTY locked.
- */
-static void
-tty_expand_tab(struct tty *tty)
-{
-    for (size_t i = 0; i < tty->tab_width; ++i) {
-        tty_append_char(tty, ' ');
-    }
-}
-
-/*
- * Writes a char to the TTY.
- *
- * Returns 0 on success; non-zero value
- * is a character to be resent.
- *
- * Call with TTY locked.
- */
-static int
-tty_putch(struct tty *tty, int c)
-{
-    if (!__TEST(tty->t_oflag, OPOST)) {
-        /*
-         * Just write out the char with
-         * no processing.
-         */
-        tty_append_char(tty, c);
-        return 0;
-    }
-
-    switch (c) {
-    case ASCII_HT:
-        /* Tab */
-        tty_expand_tab(tty);
-        break;
-    case ASCII_LF:
-        /* Line feed ('\n') */
-        tty_newline(tty);
-        break;
-    default:
-        tty_append_char(tty, c);
-        break;
-    }
-
-    return 0;
-}
-
-/*
- * Flushes a TTY specified by `tty`.
- *
- * Call with TTY locked.
- */
-void
-tty_flush(struct tty *tty)
-{
-    struct tty_ring *ring;
-
-    ring = &tty->ring;
-
-    /*
-     * Write each byte from the buffer
-     * to the screen with output processing
-     * if possible.
-     *
-     * XXX: Perhaps there could be a faster
-     *      way of doing this instead of
-     *      byte by byte?
-     */
-    for (size_t i = 0; i < ring->len; ++i) {
-        tty_putch(tty, ring->buf[i]);
-    }
-
-    ring->len = 0;
-}
-
-/*
- * Writes to a TTY specified by `tty`.
- *
- * @buf: Buffer to write.
- * @len: Length of buffer.
- *
- * Returns number of bytes written, and
- * EXIT_FAILURE on error.
- */
-ssize_t
-tty_write(struct tty *tty, const char *buf, size_t len)
-{
-    if (len == 0) {
-        /* Bad value, don't even try */
-        return EXIT_FAILURE;
-    }
-
-    TTY_LOCK(tty);
-    for (size_t i = 0; i < len; ++i) {
-        tty_push_char(tty, buf[i]);
-        /*
-         * If we have a newline and we are
-         * buffering bytes, flush the ring.
-         */
-        if (buf[i] == '\n' && __TEST(tty->t_oflag, ORBUF)) {
-            tty_flush(tty);
-        }
-    }
-
-    /*
-     * If we aren't buffering bytes, don't
-     * keep the bytes within the ring and
-     * flush it right away per `tty_write()`
-     * call.
-     */
-    if (!__TEST(tty->t_oflag, ORBUF)) {
-        tty_flush(tty);
-    }
-
-    TTY_UNLOCK(tty);
-    return len;
-}
-
-/*
- * Sets TTY fields to their defaults.
- */
-void
-tty_set_defaults(struct tty *tty)
-{
-    /* Ensure everything is initially zero */
-    memset(tty, 0, sizeof(*tty));
-
-    /*
-     * Now, initialize everything to their defaults.
-     *
-     * Some notes about the default framebuffer device:
-     * ------------------------------------------------
-     *  The default framebuffer device should be the
-     *  front buffer. Later on during boot, all attached
-     *  TTYs shall have their fbdev swapped out with a
-     *  backbuffer to improve performace as reading directly
-     *  from video memory is going to be slow.
-     *
-     *  XXX: At some point we should be allocating a backbuffer
-     *       instead when it's time for *all* TTYs to have them.
-     *
-     *       A good idea would be to only allocate a backbuffer
-     *       *if* we switched to some TTY and deallocate
-     *       that backbuffer when switching away from that TTY.
-     *
-     *       The first thing that comes to mind when thinking
-     *       about this idea is loosing our text when we switch
-     *       back out. To rectify this, we could buffer chars
-     *       which would take less memory than keeping the whole
-     *       backbuffer (holds pixels i.e uint32_t).
-     *
-     *       This can perhaps be done by some internal flag which
-     *       indicates that kmalloc() is usable and chars can
-     *       be buffered. Once we switch back, just allocate
-     *       a new backbuffer and copy the chars back.
-     */
-    tty->fbdev = fbdev_get_front();
-    tty->t_oflag = (OPOST | ORBUF);
-    tty->tab_width = DEFAULT_TAB_WIDTH;
-    tty->fg = 0x808080;
-    tty->bg = 0x000000;
-    tty->t_ws_xpixel = tty->fbdev.width;
-    tty->t_ws_ypixel = tty->fbdev.height;
-    tty->t_ws_row = tty->fbdev.height / FONT_HEIGHT;
-    tty->t_ws_col = tty->fbdev.width / FONT_WIDTH;
-
-}
-
-void
-tty_attach(struct tty *tty)
-{
-    TAILQ_INSERT_TAIL(&tty_list, tty, link);
-    tty_draw_cursor(tty, false);
-}
-
-void
-tty_init(void)
-{
-    TAILQ_INIT(&tty_list);  /* Ensure the TTY list is usable */
-}