[hackers] [scroll] don't scroll if alternative screen is active || Jan Klemkow

From: <git_AT_suckless.org>
Date: Thu, 2 Apr 2020 23:05:24 +0200 (CEST)

commit db13d11496626604931053ac2d5a12f022efca43
Author: Jan Klemkow <j.klemkow_AT_wemelug.de>
AuthorDate: Thu Apr 2 23:02:38 2020 +0200
Commit: Jan Klemkow <j.klemkow_AT_wemelug.de>
CommitDate: Thu Apr 2 23:02:38 2020 +0200

    don't scroll if alternative screen is active

diff --git a/scroll.c b/scroll.c
index 69189ae..ceed4ef 100644
--- a/scroll.c
+++ b/scroll.c
_AT_@ -58,6 +58,7 @@ pid_t child;
 int mfd;
 struct termios dfl;
 struct winsize ws;
+static bool altscreen = false; /* is alternative screen active */
 
 void
 die(const char *fmt, ...)
_AT_@ -188,7 +189,6 @@ strelen(const char *buf, size_t size)
 bool
 isaltscreen(char c)
 {
- static bool alt = false;
         static enum {CHAR, BREK, ESC} state = CHAR;
         static char buf[BUFSIZ];
         static size_t i = 0;
_AT_@ -219,18 +219,18 @@ isaltscreen(char c)
                         if (strcmp(buf, "?1049h") == 0 ||
                             strcmp(buf, "?1047h") == 0 ||
                             strcmp(buf, "?47h" ) == 0)
- alt = true;
+ altscreen = true;
 
                         /* esc seq. disable alternative screen */
                         if (strcmp(buf, "?1049l") == 0 ||
                             strcmp(buf, "?1047l") == 0 ||
                             strcmp(buf, "?47l" ) == 0)
- alt = false;
+ altscreen = false;
                 }
                 break;
         }
 
- return alt;
+ return altscreen;
 }
 
 void
_AT_@ -389,11 +389,13 @@ main(int argc, char *argv[])
                         if (n <= 0 && errno != EINTR)
                                 die("read:");
 
- if (strncmp(KB_SCROLL_UP, input, n) == 0 ||
- strncmp(MS_SCROLL_UP, input, n) == 0)
+ if (!altscreen &&
+ (strncmp(KB_SCROLL_UP, input, n) == 0 ||
+ strncmp(MS_SCROLL_UP, input, n) == 0))
                                 scrollup();
- else if (strncmp(KB_SCROLL_DOWN, input, n) == 0 ||
- strncmp(MS_SCROLL_DOWN, input, n) == 0)
+ else if (!altscreen &&
+ (strncmp(KB_SCROLL_DOWN, input, n) == 0 ||
+ strncmp(MS_SCROLL_DOWN, input, n) == 0))
                                 scrolldown(buf, pos);
                         else if (write(mfd, input, n) == -1)
                                 die("write:");
Received on Thu Apr 02 2020 - 23:05:24 CEST