usttrace

   1 #!/bin/bash
   2
   3 # usttrace  by Pierre-Marc Fournier 2009
   4 # Distributed under the GPLv2.
   5
   6 function error() {
   7         echo "$0: error: $1" 2>/dev/stderr
   8 }
   9
  10 USTTRACE_DIR="$(dirname $0)"
  11 if [ -x "${USTTRACE_DIR}/ustd/ustd" ] ; then
  12     # Use the not installed libraries instead
  13     USTD="${USTTRACE_DIR}/ustd/ustd"
  14     LIBINTERFORK_PATH="${USTTRACE_DIR}/libinterfork/.libs/libinterfork.so"
  15     LIBMALLOCWRAP_PATH="${USTTRACE_DIR}/libmallocwrap/.libs/libmallocwrap.so"
  16     LIBUST_PATH="${USTTRACE_DIR}/libust/.libs/libust.so"
  17 else
  18     # Use the libraries that the dynamic link finds
  19     USTD="ustd"
  20     if [ ! -x "$(which ustd 2>/dev/null)" ]; then
  21         error "cannot find an executable ustd; make sure its location is in the PATH"
  22         exit 1
  23     fi
  24     LIBINTERFORK_PATH="libinterfork.so"
  25     LIBMALLOCWRAP_PATH="libmallocwrap.so"
  26     LIBUST_PATH="libust.so"
  27 fi
  28
  29 BASE_TRACE_DIR="${HOME}/.usttraces"
  30
  31 function usage () {
  32         echo "usage:  $0 OPTIONS COMMAND" 2>/dev/stderr
  33         echo "" 2>/dev/stderr
  34         echo "Options:" 2>/dev/stderr
  35         echo "    -l    Runtime link with UST library." 2>/dev/stderr
  36         echo "          (Needed only if program was not linked at compile time with libust.)" 2>/dev/stderr
  37         echo "    -L    Add path to ust libraries to LD_LIBRARY_PATH." 2>/dev/stderr
  38         echo "    -m    Instrument malloc calls." 2>/dev/stderr
  39         echo "    -f    Also trace forked processes." 2>/dev/stderr
  40         echo "    -s    Use system-wide daemon instead of creating one for this session." 2>/dev/stderr
  41 }
  42
  43 while getopts ":hlLmfs" options; do
  44         case $options in
  45                 l) arg_preload_libust=1;;
  46                 L) arg_ld_std_ust=1;;
  47                 m) arg_preload_malloc=1;;
  48                 f) arg_preload_fork=1;;
  49                 s) arg_syswide_daemon=1;;
  50                 h) usage;
  51                    exit 0;;
  52                 \?) usage
  53                         exit 1;;
  54                 *) usage
  55                         exit 1;;
  56         esac
  57 done
  58 shift $(($OPTIND - 1))
  59
  60 # Prepare vars
  61 CMD=$*
  62
  63 # Validate input
  64 if [ -z "$HOME" ];
  65 then
  66         error "no home specified"
  67 fi
  68
  69 if [ -z "$CMD" ];
  70 then
  71         error "no command specified"
  72         usage;
  73         exit 1
  74 fi
  75
  76 # Create directory for trace output
  77 DATESTRING="$(hostname)-$(date +%Y%m%d%H%M%S)"
  78 OUTDIR="$BASE_TRACE_DIR/$DATESTRING"
  79 mkdir -p "$OUTDIR"
  80
  81 # Choose socket path
  82 SOCKPATH="/tmp/ust-sock-$$"
  83
  84 if [ "$arg_syswide_daemon" != "1" ];
  85 then
  86         pidfilepath="/tmp/usttrace-$USER-$(date +%Y%m%d%H%M%S%N)-ustd-pid"
  87         mkfifo -m 0600 "$pidfilepath"
  88         # Start daemon
  89         $USTD --pidfile "$pidfilepath" -s "$SOCKPATH" -o "$OUTDIR" >"$OUTDIR/ustd.log" 2>&1 &
  90         USTDPID="$(<$pidfilepath)"
  91         export UST_DAEMON_SOCKET="$SOCKPATH"
  92 fi
  93
  94 # Establish the environment for the command
  95 (
  96     export UST_TRACE=1
  97     export UST_AUTOPROBE=1
  98
  99     if [ "$arg_preload_libust" = "1" ];
 100     then
 101         if [ -n "${LIBUST_PATH%libust.so}" ] ; then
 102             export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:${LIBUST_PATH%libust.so}"
 103         fi
 104         export LD_PRELOAD="$LD_PRELOAD:$LIBUST_PATH"
 105     fi
 106
 107     if [ "$arg_ld_std_ust" = "1" ];
 108     then
 109         if [ -n "$${LIBUST_PATH%libust.so}" ] ; then
 110             export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:${LIBUST_PATH%libust.so}"
 111         fi
 112     fi
 113
 114     if [ "$arg_preload_malloc" = "1" ];
 115     then
 116         export LD_PRELOAD="$LD_PRELOAD:$LIBMALLOCWRAP_PATH"
 117     fi
 118
 119     if [ "$arg_preload_fork" = "1" ];
 120     then
 121         export LD_PRELOAD="$LD_PRELOAD:$LIBINTERFORK_PATH"
 122     fi
 123
 124 # Install a handler for SIGIO. This is the signal that will be sent by ustd to
 125 # the traced program to trigger the creation of its listener thread. However,
 126 # it is possible that the SIGIO will be sent after the shell fork, but before
 127 # the exec of the command. If this handler isn't there, bash might terminate
 128 # because of a unhandled signal.
 129
 130 # Execute the command
 131     $CMD 2>&1
 132 ) | tee "$OUTDIR/app.log"
 133
 134 ## Because of the keepalive mechanism, we're sure that by the time
 135 ## we get here, the daemon is connected to all the buffers that still exist.
 136 ## Therefore we can politely ask it to die when it's done.
 137
 138 if [ "$arg_syswide_daemon" != "1" ];
 139 then
 140         # Tell the daemon to die
 141         kill -SIGTERM "$USTDPID"
 142
 143         echo "Waiting for ustd to shutdown..."
 144         wait "$USTDPID"
 145
 146         rm "$pidfilepath"
 147 fi
 148
 149 echo "Trace was output in: " $OUTDIR