term_init() and term_cleanup(), mostly

1 files changed, 57 insertions, 3 deletions

diff --git a/framebuffer.c b/framebuffer.c
index b6e922e..66b8c2f 100644
--- a/framebuffer.c
+++ b/framebuffer.c
@@ -1,7 +1,14 @@
 #include <stdlib.h>
+#include <termios.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
 
 #include "framebuffer.h"
 
+size_t term_width = 0,
+       term_height = 0;
+struct termios initial_terminal_state = {0};
+
 Framebuffer fb_new(size_t width, size_t height) {
     Framebuffer fb;
 
@@ -52,8 +59,55 @@ void inline fb_put(Framebuffer fb, size_t row, size_t col, Pixel pixel) {
     fb.fb[row][col] = pixel;
 }
 
-void fb_init(void);
+void term_init(void) {
+    tcgetattr(0, &initial_terminal_state);
+
+    struct termios new = initial_terminal_state;
+
+    new.c_lflag &= ~ICANON;   /* Turn off canonical mode */
+    new.c_lflag &= ~ECHO;     /* Turn off echoing */
+    new.c_cc[VMIN] = 1;       /* One char at a time */
+    new.c_cc[VTIME] = 0;      /* No input timeout */
+    tcsetattr(0, TCSANOW, &new);
+
+    write(STDOUT_FILENO, "\x1b[?1049h", 8); /* Alternative screen buffer */
+    write(STDOUT_FILENO, "\x1b[H", 3); /* Move cursor to top-left */
+    write(STDOUT_FILENO, "\x1b[?25l", 6); /* Hide the cursor */
+
+    term_update_size();
+}
+
+void term_cleanup(void) {
+    tcsetattr(0, TCSANOW, &initial_terminal_state);
+
+    write(STDOUT_FILENO, "\x1b[?25h", 6); /* Show the cursor */
+    write(STDOUT_FILENO, "\x1b[?1049l", 8); /* Alternative screen buffer */
+}
+
+void term_update_size(void) {
+#if defined(TIOCGWINSZ)
+    struct winsize ws;
+
+    if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == 0) {
+        term_height = ws.ws_row;
+        term_width  = ws.ws_col;
+        return;
+    }
+#elif defined(TIOCGSIZE)
+    struct ttysize ts;
+
+    if (ioctl(STDOUT_FILENO, TIOCGSIZE, &ts) == 0) {
+        term_height = ts.ts_row;
+        term_width  = ts.ts_col;
+        return;
+    }
+#else
+    #error "Neither TIOCGWINSZ or TIOCGSIZE are defined, can't proceed"
+#endif
+}
 
-void fb_cleanup(void);
+void fb_print(Framebuffer fb) {
+    write(STDOUT_FILENO, "\x1b[H", 3); /* Move cursor to top-left */
 
-void fb_print(Framebuffer fb);
+    /* TODO: finish me */
+}