Fix waiting for ustd on shutdown

[ust.git] / usttrace

diff --git a/usttrace b/usttrace
index 8377272e5514be5fcb84e7d35611f1e299a86e02..b3af05d7a167cb4da41507e09cd8230264f025af 100755 (executable)
--- a/usttrace
+++ b/usttrace
@@ -3,13 +3,14 @@
 # usttrace  by Pierre-Marc Fournier 2009
 # Distributed under the GPLv2.
 
-USTD="./ustd/ustd"
-LIBINTERFORK="./libinterfork/.libs/libinterfork.so"
-LIBMALLOCWRAP="./libmallocwrap/.libs/libmallocwrap.so"
+USTTRACE_DIR="$(dirname $0)"
+USTD="${USTTRACE_DIR}/ustd/ustd"
+LIBINTERFORK_PATH="${USTTRACE_DIR}/libinterfork/.libs/libinterfork.so"
+LIBMALLOCWRAP_PATH="${USTTRACE_DIR}/libmallocwrap/.libs/libmallocwrap.so"
 
-STD_LDLIBRARY_UST="./libust/.libs:../liburcu"
+STD_LDLIBRARY_UST="${USTTRACE_DIR}/libust/.libs"
 
-BASE_TRACE_DIR="$HOME/.usttraces"
+BASE_TRACE_DIR="${HOME}/.usttraces"
 
 function usage () {
        echo "usage:  $0 OPTIONS COMMAND" 2>/dev/stderr
@@ -20,28 +21,36 @@ function usage () {
        echo "    -L    Add path to ust libraries to LD_LIBRARY_PATH." 2>/dev/stderr
        echo "    -m    Instrument malloc calls." 2>/dev/stderr
        echo "    -f    Also trace forked processes." 2>/dev/stderr
+       echo "    -s    Use system-wide daemon instead of creating one for this session." 2>/dev/stderr
 }
 
 function error() {
        echo "$0: error: $1" 2>/dev/stderr
 }
 
-while getopts ":hlLmf" options; do
+while getopts ":hlLmfs" options; do
        case $options in
                l) arg_preload_libust=1;;
                L) arg_ld_std_ust=1;;
                m) arg_preload_malloc=1;;
                f) arg_preload_fork=1;;
+               s) arg_syswide_daemon=1;;
                h) usage;
                   exit 0;;
-               \?) echo $usage
+               \?) usage
                        exit 1;;
-               *) echo $usage
+               *) usage
                        exit 1;;
        esac
 done
 shift $(($OPTIND - 1))
 
+if [ ! -x "$USTD" ];
+then
+       error "specified path to ustd not executable ($USTD)"
+       exit 1
+fi
+
 # Prepare vars
 CMD=$1
 
@@ -66,14 +75,19 @@ mkdir -p "$OUTDIR"
 # Choose socket path
 SOCKPATH="/tmp/ust-sock-$$"
 
-# Start daemon
-$USTD -s "$SOCKPATH" -o "$OUTDIR" >"$OUTDIR/ustd.log" 2>&1 &
-USTDPID=$!
+if [ "$arg_syswide_daemon" != "1" ];
+then
+       pidfilepath="/tmp/usttrace-$USER-$(date +%Y%m%d%H%M%S%N)-ustd-pid"
+       mkfifo -m 0600 "$pidfilepath"
+       # Start daemon
+       $USTD -d --pidfile "$pidfilepath" -s "$SOCKPATH" -o "$OUTDIR" >"$OUTDIR/ustd.log" 2>&1 &
+       USTDPID="$(<$pidfilepath)"
+       export UST_DAEMON_SOCKET="$SOCKPATH"
+fi
 
 # Establish the environment for the command
 export UST_TRACE=1
 export UST_AUTOPROBE=1
-export UST_DAEMON_SOCKET="$SOCKPATH"
 
 if [ "$arg_preload_libust" = "1" ];
 then
@@ -81,6 +95,11 @@ then
        export LD_PRELOAD="$LD_PRELOAD:./libust/.libs/libust.so"
 fi
 
+if [ "$arg_ld_std_ust" = "1" ];
+then
+       export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$STD_LDLIBRARY_UST"
+fi
+
 if [ "$arg_preload_malloc" = "1" ];
 then
        export LD_PRELOAD="$LD_PRELOAD:./libmallocwrap/.libs/libmallocwrap.so"
@@ -88,23 +107,31 @@ fi
 
 if [ "$arg_preload_fork" = "1" ];
 then
-       export LD_PRELOAD="$LD_PRELOAD:./libinterfork/.libs/libinterfork.so"
+       export LD_PRELOAD="$LD_PRELOAD:$LIBINTERFORK_PATH"
 fi
 
-if [ "$arg_ld_std_ust" = "1" ];
-then
-       export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$STD_LDLIBRARY_UST"
-fi
+# Install a handler for SIGIO. This is the signal that will be sent by ustd to
+# the traced program to trigger the creation of its listener thread. However,
+# it is possible that the SIGIO will be sent after the shell fork, but before
+# the exec of the command. If this handler isn't there, bash might terminate
+# because of a unhandled signal.
 
 # Execute the command
-bash -c "$CMD"
+bash -c "$CMD" 2>&1 | tee "$OUTDIR/app.log"
 
 ## Because of the keepalive mechanism, we're sure that by the time
 ## we get here, the daemon is connected to all the buffers that still exist.
 ## Therefore we can politely ask it to die when it's done.
 
-kill -SIGTERM "$USTDPID"
+if [ "$arg_syswide_daemon" != "1" ];
+then
+       # Tell the daemon to die
+       kill -SIGTERM "$USTDPID"
+
+       echo "Waiting for ustd to shutdown..."
+       wait
+
+       rm "$pidfilepath"
+fi
 
-# Tell the daemon to die
-echo "Waiting for ustd to shutdown..."
-wait "$USTDPID"
+echo "Trace was output in: " $OUTDIR