From: Lennart Poettering <lennart@poettering.net>
Date: Wed, 17 Jul 2024 15:45:26 +0000 (+0200)
Subject: terminal-util: add recognizable error if cols/rows of tty are initially not initialized
X-Git-Tag: v257-rc1~873^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0ea4198f0a9ef4aa2226b437bfa6e9a741ea99b0;p=thirdparty%2Fsystemd.git

terminal-util: add recognizable error if cols/rows of tty are initially not initialized

Various tty types come up with cols/rows not initialized (i.e. set to
zero). Let's detect these cases, and return a better error than EIO,
simply to make things easier to debug.
---

diff --git a/src/basic/terminal-util.c b/src/basic/terminal-util.c
index df091c36a96..c2ff3ca85a8 100644
--- a/src/basic/terminal-util.c
+++ b/src/basic/terminal-util.c
@@ -855,7 +855,7 @@ int fd_columns(int fd) {
                 return -errno;
 
         if (ws.ws_col <= 0)
-                return -EIO;
+                return -ENODATA; /* some tty types come up with invalid row/column initially, return a recognizable error for that */
 
         return ws.ws_col;
 }
@@ -892,7 +892,7 @@ int fd_lines(int fd) {
                 return -errno;
 
         if (ws.ws_row <= 0)
-                return -EIO;
+                return -ENODATA; /* some tty types come up with invalid row/column initially, return a recognizable error for that */
 
         return ws.ws_row;
 }