From 2228468a6db1e648c69849860d30867c0e77650e Mon Sep 17 00:00:00 2001
From: AtomToast <reg-2@t-online.de>
Date: Wed, 29 Apr 2020 02:31:29 +0200
Subject: [PATCH] apply Luke Smiths external pipe eternal patch

Enables external pipe to work on the entire scrollback history.

Source: https://github.com/LukeSmithxyz/st/commit/da13ef12463d1870caed94584db464d68c6b3182
Made to work on semi-vanilla st.

This patch requires both externalpipe and scrollback patch in order to work
---
 st.c | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/st.c b/st.c
index d4c88a2..2716f44 100644
--- a/st.c
+++ b/st.c
@@ -46,6 +46,7 @@
 #define TLINE(y)		((y) < term.scr ? term.hist[((y) + term.histi - \
 				term.scr + HISTSIZE + 1) % HISTSIZE] : \
 				term.line[(y) - term.scr])
+#define TLINE_HIST(y)           ((y) <= HISTSIZE-term.row+2 ? term.hist[(y)] : term.line[(y-HISTSIZE+term.row-3)])
 
 enum term_mode {
 	MODE_WRAP        = 1 << 0,
@@ -431,6 +432,20 @@ tlinelen(int y)
 	return i;
 }
 
+int
+tlinehistlen(int y)
+{
+	int i = term.col;
+
+	if (TLINE_HIST(y)[i - 1].mode & ATTR_WRAP)
+		return i;
+
+	while (i > 0 && TLINE_HIST(y)[i - 1].u == ' ')
+		--i;
+
+	return i;
+}
+
 void
 selstart(int col, int row, int snap)
 {
@@ -2025,16 +2040,18 @@ externalpipe(const Arg *arg)
 	/* ignore sigpipe for now, in case child exists early */
 	oldsigpipe = signal(SIGPIPE, SIG_IGN);
 	newline = 0;
-	for (n = 0; n < term.row; n++) {
-		bp = term.line[n];
-		lastpos = MIN(tlinelen(n) + 1, term.col) - 1;
+	for (n = 0; n <= HISTSIZE + 2; n++) {
+		bp = TLINE_HIST(n);
+		lastpos = MIN(tlinehistlen(n) + 1, term.col) - 1;
 		if (lastpos < 0)
 			break;
+        if (lastpos == 0)
+            continue;
 		end = &bp[lastpos + 1];
 		for (; bp < end; ++bp)
 			if (xwrite(to[1], buf, utf8encode(bp->u, buf)) < 0)
 				break;
-		if ((newline = term.line[n][lastpos].mode & ATTR_WRAP))
+		if ((newline = TLINE_HIST(n)[lastpos].mode & ATTR_WRAP))
 			continue;
 		if (xwrite(to[1], "\n", 1) < 0)
 			break;
-- 
2.26.2