term_init() and term_cleanup(), mostly

3 files changed, 78 insertions, 7 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 */
+}
diff --git a/framebuffer.h b/framebuffer.h
index 1b0254f..373cfb4 100644
--- a/framebuffer.h
+++ b/framebuffer.h
@@ -5,8 +5,9 @@
 #include <stddef.h>    /* wchar_t */
 #include <sys/types.h> /* ssize_t */
 
-/* Globals for the terminal size, set by fb_init() */
-extern size_t TERM_WIDTH, TERM_HEIGHT;
+/* Globals for the terminal size, set by term_update_size() */
+extern size_t term_width, term_height;
+extern struct termios initial_terminal_state;
 
 /* Represents a 24 bit colour, 8 bit per channel */
 typedef struct Colour_s {
@@ -60,12 +61,18 @@ void fb_fill(Framebuffer fb, Pixel pixel);
 void inline fb_put(Framebuffer fb, size_t row, size_t col, Pixel pixel);
 
 /* Initializes the terminal and sets TERM_WIDTH and TERM_HEIGHT */
-void fb_init(void);
+void term_init(void);
 
 /* Undoes everything fb_init() did */
-void fb_cleanup(void);
+void term_cleanup(void);
+
+/* Updates term_width and term_height */
+void term_update_size(void);
 
 /* Prints fb to the screen */
 void fb_print(Framebuffer fb);
 
+/* c is a byte */
+#define get_input(c) read(STDIN_FILENO, &c, 1)
+
 #endif /* FRAMEBUFFER_H_ */
diff --git a/main.c b/main.c
index 8755687..5f5fc8c 100644
--- a/main.c
+++ b/main.c
@@ -1,5 +1,15 @@
 #include <stdio.h>
+#include <unistd.h>
+
+#include "framebuffer.h"
 
 int main(void) {
+    term_init();
+
     fprintf(stderr, "Not yet implemented\n");
+
+    char c;
+    get_input(c);
+
+    term_cleanup();
 }