commit fbf0ef7678619db9e9448fb5384d6fb120b73ce3 Author: Aaron Fischer Date: Mon Sep 17 09:07:22 2018 +0200 First attempt diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..82212e7 --- /dev/null +++ b/.gitignore @@ -0,0 +1,6 @@ +kilo +*.swap +*.swp +*.swo +tags +*.c~ diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..5444450 --- /dev/null +++ b/Makefile @@ -0,0 +1,2 @@ +kilo: kilo.c + $(CC) kilo.c -o kilo -Wall -Wextra -pedantic -std=c99 diff --git a/kilo.c b/kilo.c new file mode 100644 index 0000000..35a492e --- /dev/null +++ b/kilo.c @@ -0,0 +1,180 @@ +/*** includes ***/ + +#include +#include +#include +#include +#include +#include +#include +#include + +/*** defines ***/ +#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 | 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) // CPR (custor position report) + 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'; + + 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) { + // Move cursor to the lower right as a fallback if TIOCGWINSZ does + // not work. We count the columns and rows then by hand. + if (write(STDOUT_FILENO, "\x1b[999C\x1b[999B", 12) != 12) + return -1; + return getCursorPosition(rows, cols); + return -1; + } else { + *cols = ws.ws_col; + *rows = ws.ws_row; + return 0; + } +} + +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++) { + abAppend(ab, "~", 1); + + abAppend(ab, "\x1b[K", 3); // Erase one line + if (y < E.screenrows - 1) { + abAppend(ab, "\r\n", 2); + } + } +} + +void editorRefreshScreen() { + struct abuf ab = ABUF_INIT; + + abAppend(&ab, "\x1b[?25l", 6); // Hide cursor + abAppend(&ab, "\x1b[H", 3); // CUP (cursor position) + + editorDrawRows(&ab); + + abAppend(&ab, "\x1b[H", 3); + abAppend(&ab, "\x1b[?25h", 6); // Show cursor + + write(STDOUT_FILENO, ab.b, ab.len); + abFree(&ab); +} + +/*** input ***/ + +void editorProcessKeypress() { + char c = editorReadKey(); // Blocking! + + 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; +}