granicus.if.org Git - strace/blob - futex.c

   1 /*
   2  * Copyright (c) 2002-2003 Roland McGrath  <roland@redhat.com>
   3  * Copyright (c) 2007-2008 Ulrich Drepper <drepper@redhat.com>
   4  * Copyright (c) 2009 Andreas Schwab <schwab@redhat.com>
   5  * Copyright (c) 2014-2015 Dmitry V. Levin <ldv@altlinux.org>
   6  * Copyright (c) 2014-2019 The strace developers.
   7  * All rights reserved.
   8  *
   9  * SPDX-License-Identifier: LGPL-2.1-or-later
  10  */
  11
  12 #include "defs.h"
  13
  14 #ifndef FUTEX_PRIVATE_FLAG
  15 # define FUTEX_PRIVATE_FLAG 128
  16 #endif
  17 #ifndef FUTEX_CLOCK_REALTIME
  18 # define FUTEX_CLOCK_REALTIME 256
  19 #endif
  20 #ifndef FUTEX_OP_OPARG_SHIFT
  21 # define FUTEX_OP_OPARG_SHIFT 8
  22 #endif
  23
  24 #include "xlat/futexbitset.h"
  25 #include "xlat/futexops.h"
  26 #include "xlat/futexwakeops.h"
  27 #include "xlat/futexwakecmps.h"
  28
  29 static int
  30 do_futex(struct tcb *const tcp, const print_obj_by_addr_fn print_ts)
  31 {
  32         const kernel_ulong_t uaddr = tcp->u_arg[0];
  33         const int op = tcp->u_arg[1];
  34         const int cmd = op & 127;
  35         const kernel_ulong_t timeout = tcp->u_arg[3];
  36         const kernel_ulong_t uaddr2 = tcp->u_arg[4];
  37         const unsigned int val = tcp->u_arg[2];
  38         const unsigned int val2 = tcp->u_arg[3];
  39         const unsigned int val3 = tcp->u_arg[5];
  40         const char *comment;
  41
  42         printaddr(uaddr);
  43         tprints(", ");
  44         printxval(futexops, op, "FUTEX_???");
  45         switch (cmd) {
  46         case FUTEX_WAIT:
  47                 tprintf(", %u", val);
  48                 tprints(", ");
  49                 print_ts(tcp, timeout);
  50                 break;
  51         case FUTEX_LOCK_PI:
  52                 tprints(", ");
  53                 print_ts(tcp, timeout);
  54                 break;
  55         case FUTEX_WAIT_BITSET:
  56                 tprintf(", %u", val);
  57                 tprints(", ");
  58                 print_ts(tcp, timeout);
  59                 tprints(", ");
  60                 printxval(futexbitset, val3, NULL);
  61                 break;
  62         case FUTEX_WAKE_BITSET:
  63                 tprintf(", %u", val);
  64                 tprints(", ");
  65                 printxval(futexbitset, val3, NULL);
  66                 break;
  67         case FUTEX_REQUEUE:
  68                 tprintf(", %u", val);
  69                 tprintf(", %u, ", val2);
  70                 printaddr(uaddr2);
  71                 break;
  72         case FUTEX_CMP_REQUEUE:
  73         case FUTEX_CMP_REQUEUE_PI:
  74                 tprintf(", %u", val);
  75                 tprintf(", %u, ", val2);
  76                 printaddr(uaddr2);
  77                 tprintf(", %u", val3);
  78                 break;
  79         case FUTEX_WAKE_OP:
  80                 tprintf(", %u", val);
  81                 tprintf(", %u, ", val2);
  82                 printaddr(uaddr2);
  83                 tprints(", ");
  84                 if ((val3 >> 28) & FUTEX_OP_OPARG_SHIFT) {
  85                         print_xlat(FUTEX_OP_OPARG_SHIFT);
  86                         tprints("<<28|");
  87                 }
  88                 comment = printxval(futexwakeops, (val3 >> 28) & 0x7, NULL)
  89                         ? NULL : "FUTEX_OP_???";
  90                 tprints("<<28");
  91                 tprints_comment(comment);
  92                 tprintf("|%#x<<12|", (val3 >> 12) & 0xfff);
  93                 comment = printxval(futexwakecmps, (val3 >> 24) & 0xf, NULL)
  94                         ? NULL : "FUTEX_OP_CMP_???";
  95                 tprints("<<24");
  96                 tprints_comment(comment);
  97                 tprintf("|%#x", val3 & 0xfff);
  98                 break;
  99         case FUTEX_WAIT_REQUEUE_PI:
 100                 tprintf(", %u", val);
 101                 tprints(", ");
 102                 print_ts(tcp, timeout);
 103                 tprints(", ");
 104                 printaddr(uaddr2);
 105                 break;
 106         case FUTEX_FD:
 107         case FUTEX_WAKE:
 108                 tprintf(", %u", val);
 109                 break;
 110         case FUTEX_UNLOCK_PI:
 111         case FUTEX_TRYLOCK_PI:
 112                 break;
 113         default:
 114                 tprintf(", %u", val);
 115                 tprints(", ");
 116                 printaddr(timeout);
 117                 tprints(", ");
 118                 printaddr(uaddr2);
 119                 tprintf(", %#x", val3);
 120                 break;
 121         }
 122
 123         return RVAL_DECODED;
 124 }
 125
 126 #if HAVE_ARCH_TIME32_SYSCALLS
 127 SYS_FUNC(futex_time32)
 128 {
 129         return do_futex(tcp, print_timespec32);
 130 }
 131 #endif
 132
 133 SYS_FUNC(futex_time64)
 134 {
 135         return do_futex(tcp, print_timespec64);
 136 }