Keep the terminal on the pty for interactive runsHEADmaster

exec > >(tee ...) sent slackpkg's TUI (dialog writes to stderr) into the
log pipe, so the curses interface never reached the terminal and output
was mangled. Only tee non-interactive runs now; interactive runs skip
logging and keep fds 0/1/2 on the tty. Add an INT trap so Ctrl+C aborts
with 130 instead of letting the run continue.

2 files changed, 13 insertions, 8 deletions

diff --git a/README.md b/README.md
index d49b986..e4f6dac 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ Options:
 Environment:
 
 - `INITRD` initrd to inspect (default `/boot/initrd-generic.img`)
-- `LOG` append the whole run, slackpkg output included, to this file
+- `LOG` append the non-interactive run, slackpkg output included, to this file
   (default `/var/log/dist-upgrade.log`; set it empty to disable)
 
 A logrotate rule for that log ships in `logrotate.d/dist-upgrade`; install it
@@ -41,8 +41,10 @@ to `/etc/logrotate.d/`.
 4. Lists any leftover `.new` config files.
 5. Reports whether a reboot is recommended.
 
-The full run is appended to `LOG`, with a timestamped header per run, so an
-unattended upgrade can be reviewed afterwards.
+A non-interactive run is appended to `LOG`, with a timestamped header per run,
+so an unattended upgrade can be reviewed afterwards. Interactive runs are not
+logged: slackpkg's TUI needs the terminal, and redirecting it through the log
+breaks the curses interface.
 
 If slackpkg upgrades itself mid-run (exit status 50) the script re-executes
 once from the top to finish the operation, exactly as slackpkg's own message
diff --git a/dist-upgrade b/dist-upgrade
index 0b2f7a1..a71d224 100755
--- a/dist-upgrade
+++ b/dist-upgrade
@@ -46,8 +46,8 @@ to boot.
 
 Environment:
   INITRD              initrd to inspect (default /boot/initrd-generic.img)
-  LOG                 append run output here (default /var/log/dist-upgrade.log;
-                      set empty to disable)
+  LOG                 append non-interactive run output here (default
+                      /var/log/dist-upgrade.log; set empty to disable)
 EOF
 }
 
@@ -142,16 +142,18 @@ run_step() {
 
 setup_log() {
   [ -n "$LOG" ] || return 0
+  if [ "$INTERACTIVE" -eq 1 ]; then
+    info "interactive run: not logging (slackpkg's TUI needs the terminal)"
+    return 0
+  fi
   if ! : >> "$LOG" 2>/dev/null; then
     warn "cannot write log $LOG, continuing without logging"
     LOG=""
     return 0
   fi
-  local mode=non-interactive
-  [ "$INTERACTIVE" -eq 1 ] && mode=interactive
   {
     printf '\n===== dist-upgrade %s =====\n' "$(date '+%Y-%m-%d %H:%M:%S')"
-    printf 'mode: %s\n' "$mode"
+    printf 'mode: non-interactive\n'
     printf 'args:%s\n' "$(printf ' %s' "${ORIG_ARGS[@]}")"
   } >> "$LOG"
   exec > >(tee -a "$LOG") 2>&1
@@ -299,6 +301,7 @@ setup_log
 
 TMPDIR_SNAP=$(mktemp -d) || die "mktemp failed"
 trap 'rm -rf "$TMPDIR_SNAP"' EXIT
+trap 'exit 130' INT
 
 snapshot_initrd