1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
/****************************************************************
* *
* Copyright (c) 2001-2015 Fidelity National Information *
* Services, Inc. and/or its subsidiaries. All rights reserved. *
* *
* This source code contains the intellectual property *
* of its copyright holder(s), and is made available *
* under a license. If you do not know the terms of *
* the license, please stop and do not read further. *
* *
****************************************************************/
/* do_shmat.c UNIX - Attach shared memory (stub)
* Note: The TANDEM (NonStop/UX) requires a special version of this routine
* so that attaching shared memory does not interfere with malloc.
*/
#include "mdef.h"
#include <sys/shm.h>
#include <sys/mman.h>
#include <errno.h>
#ifndef __MVS__
#include <sys/sysmacros.h>
#endif
#include "gtm_stdio.h"
#include "gtm_ipc.h"
#include "do_shmat.h"
void *do_shmat(int4 shmid, const void *shm_base, int4 shmflg)
{
# ifdef __sparc
return(shmat((int)shmid, shm_base, shmflg | SHM_SHARE_MMU));
# else
return(shmat((int)shmid, shm_base, shmflg));
# endif
}
/* This is do_shmat + capability to execute code from shared memory.
* On platforms that support the SHM_EXEC bit (as of Oct 2014 this is only Linux) we use it.
* On those that dont, we use mprotect (additional system call) on top of shmat.
* Until SHM_EXEC is not available on all POSIX platforms that GT.M is built/supported on, we need the mprotect code.
*/
void *do_shmat_exec_perm(int4 shmid, size_t shm_size, int *save_errno)
{
int4 shmflg;
void *addr;
# if defined(SHM_EXEC)
shmflg = SHM_EXEC;
# else
shmflg = 0;
# endif
addr = do_shmat(shmid, NULL, shmflg);
if (-1 == (sm_long_t)addr)
{
*save_errno = errno;
return addr;
}
# if !defined(SHM_EXEC)
if (-1 == mprotect(addr, shm_size, PROT_READ | PROT_WRITE | PROT_EXEC))
{
*save_errno = errno;
assert(FALSE);
SHMDT(addr);
addr = (void *)-1;
}
# endif
return addr;
}
|
