/*** includes ***/ #define _DEFAULT_SOURCE #define _BSD_SOURCE #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include /*** defines ***/ #define KILO_VERSION "0.0.1" #define CTRL_KEY(k) ((k) & 0x1f) enum editorKey { ARROW_LEFT = 1000, ARROW_RIGHT, ARROW_UP, ARROW_DOWN, DEL_KEY, HOME_KEY, END_KEY, PAGE_UP, PAGE_DOWN }; /*** data ***/ typedef struct erow { int size; char *chars; } erow; struct editorConfig { int cx, cy; int screenrows; int screencols; int numrows; erow *row; 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"); } int editorReadKey() { int nread; char c; while ((nread = read(STDIN_FILENO, &c, 1)) != 1) { if (nread == -1 && errno != EAGAIN) die("read"); } // Process escape sequences if (c == '\x1b') { char seq[3]; if (read(STDIN_FILENO, &seq[0], 1) != 1) return '\x1b'; if (read(STDIN_FILENO, &seq[1], 1) != 1) return '\x1b'; if (seq[0] == '[') { if (seq[1] >= '0' && seq[1] <= '9') { if (read(STDIN_FILENO, &seq[2], 1) != 1) return '\x1b'; if (seq[2] == '~') { switch (seq[1]) { case '1': return HOME_KEY; case '3': return DEL_KEY; case '4': return END_KEY; case '5': return PAGE_UP; case '6': return PAGE_DOWN; case '7': return HOME_KEY; case '8': return END_KEY; } } } else { switch (seq[1]) { case 'A': return ARROW_UP; case 'B': return ARROW_DOWN; case 'C': return ARROW_RIGHT; case 'D': return ARROW_LEFT; } } } else if (seq[0] == '0') { switch (seq[1]) { case 'H': return HOME_KEY; case 'F': return END_KEY; } } return '\x1b'; } else { 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; } } /*** row operations ***/ void editorAppendRow(char *s, size_t len) { E.row = realloc(E.row, sizeof(erow) * (E.numrows +1)); int at = E.numrows; E.row[at].size = len; E.row[at].chars = malloc(len + 1); memcpy(E.row[at].chars, s, len); E.row[at].chars[len] = '\0'; E.numrows++; } /*** file i/o ***/ void editorOpen(char *filename) { FILE *fp = fopen(filename, "r"); if (!fp) die("fopen"); char *line = NULL; size_t linecap = 0; ssize_t linelen; while ((linelen = getline(&line, &linecap, fp)) != -1) { while (linelen > 0 && (line[linelen - 1] == '\n' || line[linelen - 1] == '\r')) linelen--; editorAppendRow(line, linelen); } free(line); fclose(fp); } /*** 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.numrows) { if (E.numrows == 0 && y == E.screenrows / 3) { char welcome[80]; int welcomelen = snprintf(welcome, sizeof(welcome), "Kilo editor -- version %s", KILO_VERSION); if (welcomelen > E.screencols) welcomelen = E.screencols; int padding = (E.screencols - welcomelen) / 2; if (padding) { abAppend(ab, "~", 1); padding--; } while(padding--) abAppend(ab, " ", 1); abAppend(ab, welcome, welcomelen); } else { abAppend(ab, "~", 1); } } else { int len = E.row[y].size; if (len > E.screencols) len = E.screencols; abAppend(ab, E.row[y].chars, len); } 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); // Update cursor position char buf[32]; snprintf(buf, sizeof(buf), "\x1b[%d;%dH", E.cy +1, E.cx + 1); abAppend(&ab, buf, strlen(buf)); abAppend(&ab, "\x1b[?25h", 6); // Show cursor write(STDOUT_FILENO, ab.b, ab.len); abFree(&ab); } /*** input ***/ void editorMoveCursor(int key) { switch (key) { case ARROW_LEFT: if (E.cx != 0) { E.cx--; } break; case ARROW_RIGHT: if (E.cx != E.screencols -1) { E.cx++; } break; case ARROW_UP: if (E.cy != 0) { E.cy--; } break; case ARROW_DOWN: if (E.cy != E.screenrows -1) { E.cy++; } break; } } void editorProcessKeypress() { int c = editorReadKey(); // Blocking! switch (c) { case CTRL_KEY('q'): write(STDOUT_FILENO, "\x1b[2J", 4); write(STDOUT_FILENO, "\x1b[H", 3); exit(0); break; case HOME_KEY: E.cx = 0; break; case END_KEY: E.cx = E.screencols -1; break; case PAGE_UP: case PAGE_DOWN: { int times = E.screenrows; while(times--) editorMoveCursor(c == PAGE_UP ? ARROW_UP : ARROW_DOWN); } break; case ARROW_UP: case ARROW_DOWN: case ARROW_LEFT: case ARROW_RIGHT: editorMoveCursor(c); break; } } /*** init ***/ void initEditor() { E.cx = 0; E.cy = 0; E.numrows = 0; E.row = NULL; if (getWindowSize(&E.screenrows, &E.screencols) == -1) die("getWindowSize"); } int main(int argc, char *argv[]) { enableRawMode(); initEditor(); if (argc >= 2) { editorOpen(argv[1]); } while (1) { editorRefreshScreen(); editorProcessKeypress(); } return 0; }