padding welcome

CMakeLists.txt

@@ -3,4 +3,4 @@ project(editor)
 
 set(CMAKE_CXX_STANDARD 17)
 
-add_executable(editor kilo.cpp)
+add_executable(editor kilo.c)

kilo.c

@@ -0,0 +1,171 @@
+/*** Includes ***/
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <termios.h>
+#include <unistd.h>
+
+/** defines ***/
+#define KILO_VERSION "0.0.1"
+#define CTRL_KEY(k) ((k) & 0x1f)
+
+
+/*** data ***/
+struct editorConfig {
+    int screenrows;
+    int screencols;
+    struct termios orig_termios;
+};
+struct editorConfig E;
+
+/*** terminal ***/
+void die(const char *s){
+    write(STDOUT_FILENO, "\x1b[2J", 4);
+    write(STDOUT_FILENO, "\x1b[H", 3);
+
+    perror(s);
+    exit(1);
+}
+
+void disableRawMode() {
+    if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &E.orig_termios) == -1){
+        die("tcsetattr");
+    }
+}
+
+void enableRawMode() {
+    if(tcgetattr(STDIN_FILENO, &E.orig_termios) == -1) die("tcgetattr");
+
+    atexit(disableRawMode);
+
+    struct termios raw = E.orig_termios;
+    raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
+    raw.c_oflag &= ~(OPOST);
+    raw.c_cflag |= (CS8);
+    raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
+    raw.c_cc[VMIN] = 0;
+    raw.c_cc[VTIME] = 1;
+    if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1) die("tcsetattr");
+}
+
+char editorReadKey() {
+    int nread;
+    char c;
+    while ((nread = read(STDIN_FILENO, &c, 1)) != 1){
+        if (nread == -1 && errno != EAGAIN) die("read");
+    }
+    return c;
+}
+
+int getCursorPosition(int *rows, int *cols) {
+    char buf[32];
+    unsigned int i = 0;
+    if (write(STDOUT_FILENO, "\x1b[6n", 4) != 4) return -1;
+
+    while(i < sizeof(buf) -1) {
+        if (read(STDIN_FILENO, &buf[i], 1) != 1) break;
+        if (buf[i] == 'R') break;
+        i++;
+    }
+    buf[i] = '\0'; //assign null to final byte
+    if(buf[0] != '\x1b' || buf[1] != '[') return -1;
+    if(sscanf(&buf[2], "%d;%d", rows, cols) != 2) return -1;
+    return 0;
+}
+
+int getWindowSize(int *rows, int *cols) {
+    struct winsize ws;
+    if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
+        if (write(STDOUT_FILENO, "\x1b[999C\x1b[999B",12) != 12) return -1;
+        return getCursorPosition(rows, cols);
+    } else {
+        *cols = ws.ws_col;
+        *rows = ws.ws_row;
+        return 0;
+    }
+}
+/*** append buffer ***/
+struct abuf {
+    char *b;
+    int len;
+};
+#define ABUF_INIT {NULL, 0}
+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);
+}
+
+
+/*** output ***/
+void editorDrawRows(struct abuf *ab) {
+    int y;
+    for (y = 0; y < E.screenrows; y++){
+        if (y == E.screenrows / 3) {
+            char welcome[80];
+            int welcomelen = snprintf(welcome, sizeof welcome, "Kilo Editor -- version %s", KILO_VERSION);
+            int padding = (E.screencols - welcomelen) /2;
+            if(padding) {
+                abAppend(ab, "~", 1);
+                padding--;
+            }
+            while(padding--) abAppend(ab, " ", 1);
+            if (welcomelen > E.screencols) welcomelen = E.screencols;
+            abAppend(ab, welcome, welcomelen);
+        } else {
+            abAppend(ab, "~", 1);
+        }
+        abAppend(ab, "\x1b[K", 3);
+        if (y<E.screenrows -1) {
+            abAppend(ab, "\r\n", 2);
+        }
+    }
+}
+void editorRefreshScreen() {
+    struct abuf ab = ABUF_INIT;
+    abAppend(&ab, "\x1b[?25l", 6);
+    abAppend(&ab, "\x1b[H",3); // Cursor Position home
+    editorDrawRows(&ab);
+    abAppend(&ab, "\x1b[H",3); // Cursor Position home
+    abAppend(&ab, "\x1b[?25h", 6);
+
+    write(STDOUT_FILENO, ab.b, ab.len);
+    abFree(&ab);
+}
+
+
+/*** input ***/
+void editorProcessKeypress() {
+    char c = editorReadKey();
+    switch (c) {
+        case CTRL_KEY('q'):
+            write(STDOUT_FILENO, "\x1b[2J", 4);
+            write(STDOUT_FILENO, "\x1b[H", 3);
+            exit(0);
+            break;
+    }
+}
+
+/*** init ***/
+void initEditor() {
+      if (getWindowSize(&E.screenrows, &E.screencols) == -1) die("getWindowSize");
+}
+int main() {
+    enableRawMode();
+    initEditor();
+
+    while(1) {
+        editorRefreshScreen();
+        editorProcessKeypress();
+    }
+    return 0;
+}

kilo.cpp

@@ -1,78 +0,0 @@
-/*** Includes ***/
-#include <ctype.h>
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <termios.h>
-#include <unistd.h>
-
-/** defines ***/
-#define CTRL_KEY(k) ((k) & 0x1f)
-
-
-/*** data ***/
-struct termios orig_termios;
-
-/*** terminal ***/
-void die(const char *s){
-    perror(s);
-    exit(1);
-}
-
-void disableRawMode() {
-    if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &orig_termios) == -1){
-        die("tcsetattr");
-    }
-}
-
-void enableRawMode() {
-    if(tcgetattr(STDIN_FILENO, &orig_termios) == -1) die("tcgetattr");
-
-    atexit(disableRawMode);
-
-    struct termios raw = orig_termios;
-    raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
-    raw.c_oflag &= ~(OPOST);
-    raw.c_cflag |= (CS8);
-    raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
-    raw.c_cc[VMIN] = 0;
-    raw.c_cc[VTIME] = 1;
-    if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1) die("tcsetattr");
-}
-
-char editorReadKey() {
-    int nread;
-    char c;
-    while ((nread = read(STDIN_FILENO, &c, 1)) != 1){
-        if (nread == -1 && errno != EAGAIN) die("read");
-    }
-    return c;
-}
-
-/*** output ***/
-void editorRefreshScreen() {
-    write(STDOUT_FILENO, "\x1b[2J", 4); // Clear Screen
-    write(STDOUT_FILENO, "\x1b[H",3); // Cursor Position home
-}
-
-
-/*** input ***/
-void editorProcessKeypress() {
-    char c = editorReadKey();
-    switch (c) {
-        case CTRL_KEY('q'):
-            exit(0);
-            break;
-    }
-}
-
-/*** init ***/
-int main() {
-    enableRawMode();
-
-    while(1) {
-        editorRefreshScreen();
-        editorProcessKeypress();
-    }
-    return 0;
-}