X-Git-Url: https://git.distorted.org.uk/~mdw/profile/blobdiff_plain/9906310798d936a6cacd0ec5a2d3b607e911c423..5c1771876cc5301c2d0c7e9e28c69a01682d2429:/bin/start-ssh-agent

diff --git a/bin/start-ssh-agent b/bin/start-ssh-agent
index 542abcd..88fd657 100755
--- a/bin/start-ssh-agent
+++ b/bin/start-ssh-agent
@@ -8,16 +8,16 @@ case "${SHELL-/bin/sh}" in
   *csh*) style=csh;;
   *) style=sh;;
 esac
-force= chosen= commands=
+force=nil chosen= commands=
 while [ $# -gt 0 ]; do
   case "$1" in
-    -h | --help) echo "$usage"; exit 0;;
-    -c | --cshell | --tcsh) style=csh chosen=t;;
-    -b | --bourne | --bash | --zsh) style=sh chosen=t;;
-    -f | --force) force=t;;
-    --) shift; break;;
-    -*) echo >&2 "$usage"; exit 1;;
-    *) break;;
+    -h | --help) echo "$usage"; exit 0 ;;
+    -c | --cshell | --tcsh) style=csh chosen=t ;;
+    -b | --bourne | --bash | --zsh) style=sh chosen=t ;;
+    -f | --force) force=t ;;
+    --) shift; break ;;
+    -*) echo >&2 "$usage"; exit 1 ;;
+    *) break ;;
   esac
   shift
 done
@@ -29,46 +29,74 @@ case $chosen,$style in
     ;;
 esac
 
-### Should I start a new agent?
-case "$force,$SSH_AUTH_SOCK" in
-  t,* | ,)
-    start=t
-    ;;
-  *)
-    start=
-    set +e; ssh-add -l >/dev/null 2>&1; rc=$?; set -e
-    [ $rc -ge 2 ] && start=t
+## Check that this stands a chance of working.
+if ! type >/dev/null 2>&1 ssh-agent || ! type >/dev/null >&1 ssh-add; then
+  echo >&2 "$0: ssh not installed; chickening out"
+  exit 1
+fi
+
+## Some useful variables.
+hostname=${HOST-$(hostname)}
+user=${USER-${LOGNAME-$(id -un)}} uid=${UID-$(id -u)}
+dir=$TMPDIR/.ssh-agent.$hostname.$user
+socket=$dir/sock; pid=$dir/pid
+export SSH_AUTH_SOCK
+
+## Should I start a new agent?
+foundp=nil
+case $force in
+  nil)
+    case ${SSH_AUTH_SOCK+t} in
+      t)
+	set +e; ssh-add -l >/dev/null 2>&1; rc=$?; set -e
+	if [ $rc -lt 2 ]; then foundp=t; fi
+	;;
+    esac
+    case $foundp in
+      t) ;;
+      *)
+	for i in \
+	  "$HOME/.cache/keyring-"*"/ssh" \
+	  "/run/user/$uid/keyring/ssh" \
+	  "$socket"
+	do
+	  SSH_AUTH_SOCK=$i
+	  set +e; ssh-add -l >/dev/null 2>&1; rc=$?; set -e
+	  if [ $rc -lt 2 ]; then foundp=t; break; fi
+	done
+	;;
+    esac
     ;;
 esac
 
 ### If so, do that
-if [ "$start" ]; then
-  hostname=${HOST-$(hostname)}
-  user=${USER-${LOGNAME-$(whoami)}}
-  dir=$TMPDIR/.ssh-agent.$hostname.$user; socket=$dir/sock; pid=$dir/pid
-  mkdir -p -m700 "$dir"
-  SSH_AUTH_SOCK=$socket; export SSH_AUTH_SOCK
-  set +e; ssh-add -l >/dev/null 2>&1; rc=$?; set -e
-  if [ $rc -ge 2 ]; then
-    if [ -f "$pid" ]; then
-      kill $(cat "$pid") >/dev/null 2>&1 || :
+case $foundp in
+  nil)
+    mkdir -p -m700 "$dir"
+    SSH_AUTH_SOCK=$socket
+    p=$PATH
+    runes=
+    while :; do
+      case $p in *:*) d=${p%%:*} p=${p#*:} ;; *) d=$p p= ;; esac
+      if [ -x "${d+$d/}setsid" ]; then runes="$runes setsid"; break; fi
+      case $p in "") break ;; esac
+    done
+    set +e; ssh-add -l >/dev/null 2>&1; rc=$?; set -e
+    if [ $rc -ge 2 ]; then
+      if [ -f "$pid" ]; then
+	kill $(cat "$pid") >/dev/null 2>&1 || :
+      fi
+      rm -f "$socket" "$pid"
+      (cd /; exec $runes ssh-agent -d -a "$socket" </dev/null >/dev/null 2>&1)&
+      echo $! >"$pid"
+      SSH_AUTH_SOCK=$socket
     fi
-    rm -f "$socket" "$pid"
-    (cd /; exec ssh-agent -d -a "$socket" >/dev/null 2>&1)&
-    echo $! >"$pid"
-    SSH_AUTH_SOCK=$socket; export SSH_AUTH_SOCK
-  fi
-fi
+    ;;
+esac
 
 ### Run a program, or export the details
 case $style in
-  sh)
-    echo "SSH_AUTH_SOCK='$SSH_AUTH_SOCK'; export SSH_AUTH_SOCK"
-    ;;
-  csh)
-    echo "setenv SSH_AUTH_SOCK '$SSH_AUTH_SOCK'"
-    ;;
-  commands)
-    exec "$@"
-    ;;
+  sh) echo "SSH_AUTH_SOCK='$SSH_AUTH_SOCK'; export SSH_AUTH_SOCK" ;;
+  csh) echo "setenv SSH_AUTH_SOCK '$SSH_AUTH_SOCK'" ;;
+  commands) exec "$@" ;;
 esac