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

   1 /*
   2  * Copyright (c) 1993 Ulrich Pegelow <pegelow@moorea.uni-muenster.de>
   3  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
   4  * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
   5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
   6  * Copyright (c) 2003-2006 Roland McGrath <roland@redhat.com>
   7  * Copyright (c) 2006-2015 Dmitry V. Levin <ldv@altlinux.org>
   8  * Copyright (c) 2015-2018 The strace developers.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. The name of the author may not be used to endorse or promote products
  20  *    derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include "defs.h"
  35
  36 #ifdef HAVE_SYS_SHM_H
  37 # include <sys/shm.h>
  38 #elif defined HAVE_LINUX_SHM_H
  39 # include <linux/shm.h>
  40 #endif
  41
  42 #ifndef SHM_HUGE_SHIFT
  43 # define SHM_HUGE_SHIFT 26
  44 #endif
  45
  46 #ifndef SHM_HUGE_MASK
  47 # define SHM_HUGE_MASK 0x3f
  48 #endif
  49
  50 #include "xlat/shm_resource_flags.h"
  51 #include "xlat/shm_flags.h"
  52
  53 SYS_FUNC(shmget)
  54 {
  55         printxval(ipc_private, (unsigned int) tcp->u_arg[0], NULL);
  56         tprintf(", %" PRI_klu ", ", tcp->u_arg[1]);
  57
  58         unsigned int flags = tcp->u_arg[2] & ~0777;
  59         const unsigned int mask = SHM_HUGE_MASK << SHM_HUGE_SHIFT;
  60         const unsigned int hugetlb_value = flags & mask;
  61
  62         flags &= ~mask;
  63         if (flags || !hugetlb_value)
  64                 printflags(shm_resource_flags, flags, NULL);
  65
  66         if (hugetlb_value) {
  67                 tprintf("%s%u<<",
  68                         flags ? "|" : "",
  69                         hugetlb_value >> SHM_HUGE_SHIFT);
  70                 print_xlat_u(SHM_HUGE_SHIFT);
  71         }
  72
  73         if (flags || hugetlb_value)
  74                 tprints("|");
  75         print_numeric_umode_t(tcp->u_arg[2] & 0777);
  76
  77         return RVAL_DECODED;
  78 }
  79
  80 SYS_FUNC(shmat)
  81 {
  82         if (entering(tcp)) {
  83                 tprintf("%d, ", (int) tcp->u_arg[0]);
  84                 if (indirect_ipccall(tcp)) {
  85                         printaddr(tcp->u_arg[3]);
  86                         tprints(", ");
  87                         printflags(shm_flags, tcp->u_arg[1], "SHM_???");
  88                 } else {
  89                         printaddr(tcp->u_arg[1]);
  90                         tprints(", ");
  91                         printflags(shm_flags, tcp->u_arg[2], "SHM_???");
  92                 }
  93                 return 0;
  94         } else {
  95                 if (syserror(tcp))
  96                         return 0;
  97                 if (indirect_ipccall(tcp)) {
  98                         union {
  99                                 uint64_t r64;
 100                                 uint32_t r32;
 101                         } u;
 102                         if (umoven(tcp, tcp->u_arg[2], current_wordsize, &u) < 0)
 103                                 return RVAL_NONE;
 104                         tcp->u_rval = (sizeof(u.r32) == current_wordsize)
 105                                       ? u.r32 : u.r64;
 106                 }
 107                 return RVAL_HEX;
 108         }
 109 }
 110
 111 SYS_FUNC(shmdt)
 112 {
 113         printaddr(tcp->u_arg[indirect_ipccall(tcp) ? 3 : 0]);
 114         return RVAL_DECODED;
 115 }