less/backport-makecheck-0017-lesstest-handle-colored-text-with-less-R.patch

From 68932004a8eb935f18732913ca904e466f320753 Mon Sep 17 00:00:00 2001
From: Mark Nudelman <markn@greenwoodsoftware.com>
Date: Mon, 10 Oct 2022 12:31:36 -0700
Subject: [PATCH 11/48] lesstest: handle colored text with less -R.

---
 lesstest/display.c   | 33 ++++++++++++---------
 lesstest/lt_screen.c | 68 ++++++++++++++++++++++++++------------------
 lesstest/lt_types.h  |  6 ++++
 lesstest/runtest     |  3 +-
 4 files changed, 68 insertions(+), 42 deletions(-)

diff --git a/lesstest/display.c b/lesstest/display.c
index 5c9355e..a7e1954 100644
--- a/lesstest/display.c
+++ b/lesstest/display.c
@@ -5,8 +5,6 @@ extern TermInfo terminfo;
 
 static void display_attr(Attr attr) {
 	static Attr prev_attr = 0;
-	if (attr == prev_attr)
-		return;
 	if (prev_attr & ATTR_STANDOUT)
 		printf("%s", terminfo.exit_standout);
 	if (prev_attr & ATTR_BLINK)
@@ -26,8 +24,11 @@ static void display_attr(Attr attr) {
 	prev_attr = attr;
 }
 
-static void display_color(Color fg_color, Color bg_color) {
-printf("{%x/%x}", fg_color, bg_color);
+static void display_color(Color color) {
+	if (color == NULL_COLOR)
+		printf("\33[m");
+	else
+		printf("\33[%dm", color);
 }
 
 void display_screen(const byte* img, int imglen, int screen_width, int screen_height, int move_cursor) {
@@ -36,22 +37,28 @@ void display_screen(const byte* img, int imglen, int screen_width, int screen_he
 	int cursor_x = 0;
 	int cursor_y = 0;
 	int literal = 0;
+	Attr curr_attr = 0;
+	Color curr_color = NULL_COLOR;
 	while (imglen-- > 0) {
 		wchar ch = load_wchar(&img);
 		if (!literal) {
-			if (ch == '\\') {
+			switch (ch) {
+			case '\\':
 				literal = 1;
 				continue;
-			} else if (ch == '@') {
-				Attr attr = *img++;
-				display_attr(attr);
+			case LTS_CHAR_ATTR:
+				curr_attr = *img++;
+				display_attr(curr_attr);
+				if (curr_color != NULL_COLOR)
+					display_color(curr_color);
 				continue;
-			} else if (ch == '$') {
-				Color fg_color = *img++;
-				Color bg_color = *img++;
-				display_color(fg_color, bg_color);
+			case LTS_CHAR_COLOR:
+				curr_color = *img++;
+				display_color(curr_color);
+				if (curr_attr != 0)
+					display_attr(curr_attr);
 				continue;
-			} else if (ch == '#') {
+			case LTS_CHAR_CURSOR:
 				cursor_x = x;
 				cursor_y = y;
 				continue;
diff --git a/lesstest/lt_screen.c b/lesstest/lt_screen.c
index 3574320..6b1fde4 100644
--- a/lesstest/lt_screen.c
+++ b/lesstest/lt_screen.c
@@ -9,7 +9,7 @@
 static const char version[] = "lt_screen|v=1";
 
 int usage(void) {
-	fprintf(stderr, "usage: lt_screen\n");
+	fprintf(stderr, "usage: lt_screen [-w width] [-h height] [-qv]\n");
 	return 0;
 }
 
@@ -20,8 +20,7 @@ int usage(void) {
 typedef struct ScreenChar {
 	wchar ch;
 	Attr attr;
-	Color fg_color;
-	Color bg_color;
+	Color color;
 } ScreenChar;
 
 typedef struct ScreenState {
@@ -31,8 +30,7 @@ typedef struct ScreenState {
 	int cx;
 	int cy;
 	Attr curr_attr;
-	Color curr_fg_color;
-	Color curr_bg_color;
+	Color curr_color;
 	int param_top;
 	int params[MAX_PARAMS+1];
 	int in_esc;
@@ -53,7 +51,7 @@ static void screen_init(void) {
 	screen.cy = 0;
 	screen.in_esc = 0;
 	screen.curr_attr = 0;
-	screen.curr_fg_color = screen.curr_bg_color = 0;
+	screen.curr_color = NULL_COLOR;
 	screen.param_top = -1;
 	screen.params[0] = 0;
 }
@@ -74,7 +72,7 @@ static void param_push(int v) {
 
 static int param_pop(void){
 	if (screen.param_top < 0)
-		return 0; // missing param is assumed to be 0
+		return -1; // missing param 
 	return screen.params[screen.param_top--];
 }
 
@@ -107,17 +105,16 @@ static int screen_incr(int* px, int* py) {
 	return 1;
 }
 
-static void screen_char_set(int x, int y, wchar ch, Attr attr, Color fg_color, Color bg_color) {
+static void screen_char_set(int x, int y, wchar ch, Attr attr, Color color) {
 	ScreenChar* sc = screen_char(x, y);
 	sc->ch = ch;
 	sc->attr = attr;
-	sc->fg_color = fg_color;
-	sc->bg_color = bg_color;
+	sc->color = color;
 }
 
 static int screen_clear(int x, int y, int count) {
 	while (count-- > 0) {
-		screen_char_set(x, y, '_', 0, 0, 0);
+		screen_char_set(x, y, '_', 0, NULL_COLOR);
 		screen_incr(&x, &y);
 	}
 	return 1;
@@ -125,28 +122,25 @@ static int screen_clear(int x, int y, int count) {
 
 static int screen_read(int x, int y, int count) {
 	//write(ttyout, "$|", 2);
-	int attr = 0;
-	int fg_color = 0;
-	int bg_color = 0;
+	Attr attr = 0;
+	int color = NULL_COLOR;
 	while (count-- > 0) {
 		byte buf[32];
 		byte* bufp = buf;
 		ScreenChar* sc = screen_char(x, y);
 		if (sc->attr != attr) {
 			attr = sc->attr;
-			*bufp++ = '@';
+			*bufp++ = LTS_CHAR_ATTR;
 			*bufp++ = attr;
 		}
-		if (sc->fg_color != fg_color || sc->bg_color != bg_color) {
-			fg_color = sc->fg_color;
-			bg_color = sc->bg_color;
-			*bufp++ = '$';
-			*bufp++ = fg_color;
-			*bufp++ = bg_color;
+		if (sc->color != color) {
+			color = sc->color;
+			*bufp++ = LTS_CHAR_COLOR;
+			*bufp++ = color;
 		}
 		if (x == screen.cx && y == screen.cy)
-			*bufp++ = '#';
-		if (sc->ch == '@' || sc->ch == '$' || sc->ch == '\\' || sc->ch == '#')
+			*bufp++ = LTS_CHAR_CURSOR;
+		if (sc->ch == '\\' || sc->ch == LTS_CHAR_ATTR || sc->ch == LTS_CHAR_COLOR || sc->ch == LTS_CHAR_CURSOR)
 			*bufp++ = '\\';
 		store_wchar(&bufp, sc->ch);
 		write(ttyout, buf, bufp-buf);
@@ -189,12 +183,20 @@ static int screen_rscroll(void) {
 
 static int screen_set_attr(int attr) {
 	screen.curr_attr |= attr;
-	return 0;
+	if (verbose) fprintf(stderr, "[%d,%d] set_attr(%d)=%d\n", screen.cx, screen.cy, attr, screen.curr_attr);
+	return 1;
 }
 
 static int screen_clear_attr(int attr) {
 	screen.curr_attr &= ~attr;
-	return 0;
+	if (verbose) fprintf(stderr, "[%d,%d] clr_attr(%d)=%d\n", screen.cx, screen.cy, attr, screen.curr_attr);
+	return 1;
+}
+
+static int screen_set_color(int color) {
+	screen.curr_color = (color >= 0) ? color : NULL_COLOR;
+	if (verbose) fprintf(stderr, "[%d,%d] set_color(%d)=%d\n", screen.cx, screen.cy, color, screen.curr_color);
+	return 1;
 }
 
 // ------------------------------------------------------------------ 
@@ -223,10 +225,15 @@ static int exec_esc(wchar ch) {
 		count = param_pop();
 		y = param_pop();
 		x = param_pop();
+		if (x < 0) x = 0;
+		if (y < 0) y = 0;
+		if (count < 0) count = 0;
 		return screen_read(x, y, count);
 	case 'j': // jump cursor to (N1,N2)
 		y = param_pop();
 		x = param_pop();
+		if (x < 0) x = 0;
+		if (y < 0) y = 0;
 		return screen_move(x, y);
 	case 'g': // visual bell 
 		return 0;
@@ -256,6 +263,8 @@ static int exec_esc(wchar ch) {
 		return screen_clear_attr(ATTR_BLINK);
 	case 'E': // exit bold/blink
 		return screen_clear_attr(ATTR_BOLD|ATTR_BLINK);
+	case 'm': // set color
+		return screen_set_color(param_pop());
 	case '?': // print version string
 		write(ttyout, version, strlen(version));
 		return 1;
@@ -266,10 +275,10 @@ static int exec_esc(wchar ch) {
 
 static int add_char(wchar ch) {
 	//if (verbose) fprintf(stderr, "add (%c) %lx at %d,%d\n", (char)ch, (long)ch, screen.cx, screen.cy);
-	screen_char_set(screen.cx, screen.cy, ch, screen.curr_attr, screen.curr_fg_color, screen.curr_bg_color);
+	screen_char_set(screen.cx, screen.cy, ch, screen.curr_attr, screen.curr_color);
 	int fits = screen_incr(&screen.cx, &screen.cy);
 	if (fits && is_wide_char(ch)) {
-		screen_char_set(screen.cx, screen.cy, 0, 0, 0, 0);
+		screen_char_set(screen.cx, screen.cy, 0, 0, NULL_COLOR);
 		fits = screen_incr(&screen.cx, &screen.cy);
 	}
 	if (!fits) { // Wrap at bottom of screen = scroll
@@ -284,9 +293,12 @@ static int process_char(wchar ch) {
 	int ok = 1;
 	if (screen.in_esc) {
 		if (ch >= '0' && ch <= '9') {
-			param_push(10 * param_pop() + ch - '0');
+			int d = (screen.param_top < 0) ? 0 : screen.params[screen.param_top--];
+			param_push(10 * d + ch - '0');
 		} else if (ch == ';') {
 			param_push(0);
+		} else if (ch == '[') {
+			; // ANSI sequence
 		} else {
 			screen.in_esc = 0;
 			ok = exec_esc(ch);
diff --git a/lesstest/lt_types.h b/lesstest/lt_types.h
index 2b3c1bc..3f98376 100644
--- a/lesstest/lt_types.h
+++ b/lesstest/lt_types.h
@@ -5,6 +5,8 @@ typedef unsigned char byte;
 typedef unsigned char Attr;
 typedef unsigned char Color;
 
+#define NULL_COLOR          ((Color)0xff)
+
 #define ATTR_BOLD           (1<<0)
 #define ATTR_UNDERLINE      (1<<1)
 #define ATTR_STANDOUT       (1<<2)
@@ -18,6 +20,10 @@ typedef unsigned char Color;
 #define RUN_OK              0
 #define RUN_ERR             1
 
+#define LTS_CHAR_ATTR       '@'
+#define LTS_CHAR_COLOR      '$'
+#define LTS_CHAR_CURSOR     '#'
+
 #define is_ascii(ch)        ((ch) >= ' ' && (ch) < 0x7f)
 #define pr_ascii(ch)        (is_ascii(ch) ? ((char)ch) : '.')
 
diff --git a/lesstest/runtest b/lesstest/runtest
index fe7fcab..2a39047 100755
--- a/lesstest/runtest
+++ b/lesstest/runtest
@@ -59,7 +59,8 @@ sub run {
 		print "ERR  cannot open $file\n";
 		return 1;
 	}
-	print "TEST $file\n";
+	my ($basename) = $file =~ m|^.*/([^/]+)$|;
+	print "TEST $basename\n";
 	my $cmd = "$lesstest $lt_opts -s '$lt_screen' -t '$file' '$less'";
 	my $err = system $cmd;
 	if ($err) {
-- 
2.27.0