nasmfm

commit 6c865f04f3cce5ed4502fc32b8e2a044e6d33ec2
parent bb1400f138800794a5f2dc0e953e09098eecf2bc
Author: afify <hassan@afify.dev>
Date:   Wed,  9 Mar 2022 16:29:30 +0300

[feat] add buffer before write

Diffstat:
M
nasmfm.c
 | 
71
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------

1 file changed, 60 insertions(+), 11 deletions(-)
diff --git a/nasmfm.c b/nasmfm.c
@@ -6,18 +6,23 @@
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <termios.h>
 #include <unistd.h>
 
 /* macros */
 #define CTRL_KEY(k) ((k)&0x1f)
-#define CLEAR_SCREEN write(STDOUT_FILENO, "\x1b[2J", 4);
-#define CURSOR_TOP_LEFT write(STDOUT_FILENO, "\x1b[H", 3);
+#define CLEAR_SCREEN    abAppend(&ab, "\x1b[2J",   4);
+#define CURSOR_TOP_LEFT abAppend(&ab, "\x1b[H",    3);
+#define CURSOR_HIDE     abAppend(&ab, "\x1b[?25l", 6);
+#define CURSOR_SHOW     abAppend(&ab, "\x1b[?25h", 6);
+#define ABUF_INIT       \
+	{               \
+		NULL, 0 \
+	}
 
 /* typedef */
 /* function declarations */
-/* global variables */
-/* function implementations */
 
 typedef struct {
 	int rows;
@@ -25,8 +30,31 @@ typedef struct {
 	struct termios orig_termios;
 } Term;
 
+struct abuf {
+	char *b;
+	int len;
+};
+
+/* global variables */
 Term term;
 
+/* function implementations */
+void
+abAppend(struct abuf *ab, const char *s, int len)
+{
+	char *new = realloc(ab->b, ab->len + len);
+	if (new == NULL)
+		return;
+	memcpy(&new[ab->len], s, len);
+	ab->b = new;
+	ab->len += len;
+}
+void
+abFree(struct abuf *ab)
+{
+	free(ab->b);
+}
+
 void
 die(const char *s)
 {
@@ -61,14 +89,32 @@ enableRawMode()
 	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1)
 		die("tcsetattr");
 }
+
 void
-editorDrawRows()
+editorDrawRows(struct abuf *ab)
 {
 	int y;
 	for (y = 0; y < term.rows; y++) {
-		write(STDOUT_FILENO, "~", 1);
+		if (y == term.rows / 3) {
+			char welcome[80];
+			int welcomelen = snprintf(welcome, sizeof(welcome),
+				"Kilo editor -- version nasmfm");
+			if (welcomelen > term.cols)
+				welcomelen = term.cols;
+			int padding = (term.cols - welcomelen) / 2;
+			if (padding) {
+				abAppend(ab, "~", 1);
+				padding--;
+			}
+			while (padding--)
+				abAppend(ab, " ", 1);
+			abAppend(ab, welcome, welcomelen);
+		} else {
+			abAppend(ab, "~", 1);
+		}
+		abAppend(ab, "\x1b[K", 3);
 		if (y < term.rows - 1) {
-			write(STDOUT_FILENO, "\r\n", 2);
+			abAppend(ab, "\r\n", 2);
 		}
 	}
 }
@@ -76,10 +122,13 @@ editorDrawRows()
 void
 editorRefreshScreen()
 {
-	CLEAR_SCREEN
-	CURSOR_TOP_LEFT
-	editorDrawRows();
-	CURSOR_TOP_LEFT
+	struct abuf ab = ABUF_INIT;
+	//abAppend(&ab, "\x1b[2J", 4);
+	abAppend(&ab, "\x1b[H", 3);
+	editorDrawRows(&ab);
+	abAppend(&ab, "\x1b[H", 3);
+	write(STDOUT_FILENO, ab.b, ab.len);
+	abFree(&ab);
 }
 
 char