usttrace

   1 #!/bin/bash
   2
   3 # usttrace  by Pierre-Marc Fournier 2009
   4 # Distributed under the GPLv2.
   5
   6 USTD="./ustd/ustd"
   7 LIBINTERFORK_PATH="./libinterfork/.libs/libinterfork.so"
   8 LIBMALLOCWRAP_PATH="./libmallocwrap/.libs/libmallocwrap.so"
   9
  10 STD_LDLIBRARY_UST="./libust/.libs:../liburcu"
  11
  12 BASE_TRACE_DIR="$HOME/.usttraces"
  13
  14 function usage () {
  15         echo "usage:  $0 OPTIONS COMMAND" 2>/dev/stderr
  16         echo "" 2>/dev/stderr
  17         echo "Options:" 2>/dev/stderr
  18         echo "    -l    Runtime link with UST library." 2>/dev/stderr
  19         echo "          (Needed only if program was not linked at compile time with libust.)" 2>/dev/stderr
  20         echo "    -L    Add path to ust libraries to LD_LIBRARY_PATH." 2>/dev/stderr
  21         echo "    -m    Instrument malloc calls." 2>/dev/stderr
  22         echo "    -f    Also trace forked processes." 2>/dev/stderr
  23         echo "    -s    Use system-wide daemon instead of creating one for this session." 2>/dev/stderr
  24 }
  25
  26 function error() {
  27         echo "$0: error: $1" 2>/dev/stderr
  28 }
  29
  30 while getopts ":hlLmfs" options; do
  31         case $options in
  32                 l) arg_preload_libust=1;;
  33                 L) arg_ld_std_ust=1;;
  34                 m) arg_preload_malloc=1;;
  35                 f) arg_preload_fork=1;;
  36                 s) arg_syswide_daemon=1;;
  37                 h) usage;
  38                    exit 0;;
  39                 \?) usage
  40                         exit 1;;
  41                 *) usage
  42                         exit 1;;
  43         esac
  44 done
  45 shift $(($OPTIND - 1))
  46
  47 # Prepare vars
  48 CMD=$1
  49
  50 # Validate input
  51 if [ -z "$HOME" ];
  52 then
  53         error "no home specified"
  54 fi
  55
  56 if [ -z "$CMD" ];
  57 then
  58         error "no command specified"
  59         usage;
  60         exit 1
  61 fi
  62
  63 # Create directory for trace output
  64 DATESTRING="$(hostname)-$(date +%Y%m%d%H%M%S)"
  65 OUTDIR="$BASE_TRACE_DIR/$DATESTRING"
  66 mkdir -p "$OUTDIR"
  67
  68 # Choose socket path
  69 SOCKPATH="/tmp/ust-sock-$$"
  70
  71 if [ "$arg_syswide_daemon" != "1" ];
  72 then
  73         # Start daemon
  74         $USTD -s "$SOCKPATH" -o "$OUTDIR" 2>&1 >"$OUTDIR/ustd.log" &
  75         USTDPID="$!"
  76         export UST_DAEMON_SOCKET="$SOCKPATH"
  77 fi
  78
  79 # Wait for the daemon to settle
  80 # If we don't, the process may try to connect to its socket before
  81 # it's ready.
  82 # FIXME: is there a way to make sure this works every time?
  83 sleep 0.5
  84
  85 # Establish the environment for the command
  86 export UST_TRACE=1
  87 export UST_AUTOPROBE=1
  88
  89 if [ "$arg_preload_libust" = "1" ];
  90 then
  91         export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:./libust/.libs"
  92         export LD_PRELOAD="$LD_PRELOAD:./libust/.libs/libust.so"
  93 fi
  94
  95 if [ "$arg_ld_std_ust" = "1" ];
  96 then
  97         export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$STD_LDLIBRARY_UST"
  98 fi
  99
 100 if [ "$arg_preload_malloc" = "1" ];
 101 then
 102         export LD_PRELOAD="$LD_PRELOAD:./libmallocwrap/.libs/libmallocwrap.so"
 103 fi
 104
 105 if [ "$arg_preload_fork" = "1" ];
 106 then
 107         export LD_PRELOAD="$LD_PRELOAD:$LIBINTERFORK_PATH"
 108 fi
 109
 110 # Install a handler for SIGIO. This is the signal that will be sent by ustd to
 111 # the traced program to trigger the creation of its listener thread. However,
 112 # it is possible that the SIGIO will be sent after the shell fork, but before
 113 # the exec of the command. If this handler isn't there, bash might terminate
 114 # because of a unhandled signal.
 115
 116 # Execute the command
 117 bash -c "$CMD" 2>&1 | tee "$OUTDIR/app.log"
 118
 119 ## Because of the keepalive mechanism, we're sure that by the time
 120 ## we get here, the daemon is connected to all the buffers that still exist.
 121 ## Therefore we can politely ask it to die when it's done.
 122
 123 if [ "$arg_syswide_daemon" != "1" ];
 124 then
 125         # Tell the daemon to die
 126         kill -SIGTERM "$USTDPID"
 127
 128         echo "Waiting for ustd to shutdown..."
 129         wait "$USTDPID"
 130 fi
 131
 132 echo "Trace was output in: " $OUTDIR