first commit

4 files changed, 232 insertions, 0 deletions

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..59acc4f
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,7 @@
+all: tea
+
+%: %c
+	gcc -o $@ $<
+
+install:
+	install tea /usr/bin/tea
diff --git a/README b/README
new file mode 100644
index 0000000..b0beeee
--- /dev/null
+++ b/README
@@ -0,0 +1 @@
+Troff Editor for ANSI terminals
diff --git a/tea b/tea
new file mode 100755
index 0000000..4e7612c
--- /dev/null
+++ b/tea
diff --git a/tea.c b/tea.c
new file mode 100644
index 0000000..d580493
--- /dev/null
+++ b/tea.c
@@ -0,0 +1,224 @@
+#include <ctype.h>
+#include <err.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/ttydefaults.h>
+#include <termios.h>
+#include <unistd.h>
+
+#define ESC "\033"
+#define CSI ESC "["
+
+#define prn(...) dprintf(ttyfd, __VA_ARGS__)
+#define rerr(...) do { raw(false); err(__VA_ARGS__); } while (0)
+
+char **lines;
+int lines_c;
+int lines_s;
+
+char *src;
+int src_l;
+int src_s;
+
+int x, y; /* current cursor position */
+int w, h; /* terminal width, height */
+int margin = 10;
+
+int current = -1; /* currently selected item */
+int xorig, yorig; /* original cursor position in cols, rows */
+int ttyfd;
+
+/* enable/disable "raw" mode */
+void raw(bool enable) {
+	int r;
+	static struct termios orig;
+	struct termios raw;
+
+	if (enable) {
+		r = tcgetattr(ttyfd, &orig);
+		if (r == -1) err(1, "tcgetattr");
+
+		raw = orig;
+		raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
+		raw.c_oflag &= ~OPOST;
+		raw.c_cflag |= CS8;
+		raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
+
+		r = tcsetattr(ttyfd, TCSAFLUSH, &raw);
+		if (r == -1) err(1, "tcsetattr");
+
+	} else
+		tcsetattr(ttyfd, TCSAFLUSH, &orig);
+}
+
+/* cursor position report */
+int cpr(int *x, int *y) {
+	char c, xbuf[4], ybuf[4];
+	int i;
+
+	prn(CSI "6n");
+
+	/* get CSI */
+	read(ttyfd, &c, 1);
+	if (c != '\033') return -1;
+	read(ttyfd, &c, 1);
+	if (c != '[') return -1;
+
+	/* get x */
+	i = 0;
+	while (read(ttyfd, &c, 1) && c != ';') {
+		if (i > 3 || !isdigit(c)) return -1;
+		ybuf[i++] = c;
+	}
+	if (i == 0) return -1;
+	ybuf[i] = '\0';
+
+	/* get y */
+	i = 0;
+	while (read(ttyfd, &c, 1) && c != 'R') {
+		if (i > 3 || !isdigit(c)) return -1;
+		xbuf[i++] = c;
+	}
+	if (i == 0) return -1;
+	xbuf[i] = '\0';
+
+	*x = atoi(xbuf);
+	*y = atoi(ybuf);
+
+	return 0;
+}
+
+int up() { }
+int down() { }
+int right() {}
+int left() {}
+
+void addc(char c) {
+	if (c != '\n' && x + 1 > w) {
+		prn("\r");
+		addc('\n');
+		x = margin + 1;
+		prn(CSI "%dC", margin - 1);
+		if (y == h) yorig--;
+		else y++;
+	} else
+		x++;
+	if (src_l + 2 > src_s) {
+		fprintf(stderr, "too big!\n");
+		exit(1);
+	}
+	src[++src_l] = c;
+	src[src_l + 1] = '\0';
+	prn("%c", c);
+}
+
+int main() {
+	char c, *line, *p, *tmp;
+	int i, line_s, r;
+	struct winsize ws;
+
+	src_s = 1000;
+	src = malloc((src_s + 1) * sizeof(char));
+	if (src == NULL) err(1, "malloc");
+	src_l = -1;
+
+	ttyfd = open("/dev/tty", O_RDWR);
+	if (ttyfd == -1) rerr(1, "open");
+
+	/* read file */
+
+/*
+	line_s = 100;
+	line = malloc((line_s + 1) * sizeof(char));
+	if (line == NULL) err(1, "malloc");
+
+	lines_c = 0;
+	lines_s = 50;
+	lines = malloc(lines_s * sizeof(char *));
+	if (lines == NULL) err(1, "malloc");
+
+	i = 0;
+	while (read(STDIN_FILENO, &c, 1) != 0) {
+		if (c == '\n') {
+			line[i] = '\0';
+			lines[lines_c] = malloc((strlen(line) + 1) * sizeof(char));
+			if (lines[lines_c] == NULL) err(1, "malloc");
+			strcpy(lines[lines_c], line);
+			lines_c++;
+			i = 0;
+		} else {
+			if (i > line_s) {
+				line_s += 50;
+				tmp = realloc(line, (line_s + 1) * sizeof(char));
+				if (tmp == NULL) err(1, "realloc");
+				line = tmp;
+			}
+			line[i++] = c;
+		}
+	}
+*/
+
+	raw(true);
+
+	/* save original cursor position */
+	r = cpr(&xorig, &yorig);
+	if (r == -1) {
+		fprintf(stderr, "could not retrieve cursor position");
+		goto quit;
+	}
+
+	/* print output */
+	for (i = 0; i < lines_c; i++)
+		prn("%s\r\n", lines[i]);
+
+	/* get height of terminal */
+	r = ioctl(ttyfd, TIOCGWINSZ, &ws);
+	if (r == -1) rerr(1, "ioctl");
+	w = ws.ws_col;
+	h = ws.ws_row;
+
+	/* correct cursor position if original cursor was near bottom */
+	r = y + lines_c - h;
+	if (r > 0)
+		y = y - r;
+
+	/* restore original cursor position (CUP) */
+	prn(CSI "%d;%dH", yorig, xorig + margin - 1);
+	x = xorig + margin - 1;
+	y = yorig;
+
+	while (read(ttyfd, &c, 1) != 0) {
+		switch (c) {
+		case '\033': /* escape */
+			read(ttyfd, &c, 1);
+			if (c != '[') break;
+			read(ttyfd, &c, 1);
+			if (c == 'A') up();
+			if (c == 'B') down();
+			if (c == 'C') right();
+			if (c == 'D') left();
+			break;
+		case 3: /* ctrl-c */
+			goto quit;
+			break;
+		default:
+			if (iscntrl(c)) break;
+			addc(c);
+			break;
+		}
+	}
+quit:
+	prn(CSI "%d;%dH", yorig, xorig);
+	prn(CSI "J"); /* delete from cursor to end of display (ED) */
+	raw(false);
+	printf("%s", src);
+	return 0;
+die:
+	raw(false);
+	puts("died");
+	return 0;
+}