/*
 * Copyright 2002-2019 Intel Corporation.
 * 
 * This software is provided to you as Sample Source Code as defined in the accompanying
 * End User License Agreement for the Intel(R) Software Development Products ("Agreement")
 * section 1.L.
 * 
 * This software and the related documents are provided as is, with no express or implied
 * warranties, other than those that are expressly stated in the License.
 */

/*
 * This test verifies that Pin properly saves and restores the applicaton's
 * XMM registers when emulating a synchronous signal (i.e. fault).  The
 * application's main thread does a memory copy operation using the XMM
 * registers.  However, the copy causes a fault by accessing an illegal memory
 * location.  A handler catches the fault and fixes the address of the illegal
 * memory location.  It also modifies the XMM registers.  If Pin doesn't
 * properly save/restore the XMM registers in the handler, the main thread's
 * memory copy will be corrupted.
 */
// features.h does not exist on FreeBSD
#ifdef TARGET_LINUX
// features initializes the system's state, including the state of __USE_GNU
#include <features.h>
#endif

// If __USE_GNU is defined, we don't need to do anything.
// If we defined it ourselves, we need to undefine it later.
#ifndef __USE_GNU
    #define __USE_GNU
    #define APP_UNDEF_USE_GNU
#endif

#if defined(TARGET_MAC)
# include <sys/ucontext.h>
#else
# include <ucontext.h>
#endif

// If we defined __USE_GNU ourselves, we need to undefine it here.
#ifdef APP_UNDEF_USE_GNU
    #undef __USE_GNU
    #undef APP_UNDEF_USE_GNU
#endif


#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <stdlib.h>

#define SIZE       32
#define ALIGN      16

char *SigBuf1;
char *SigBuf2;
unsigned long Glob;


static void XmmCheck();
static void CheckBuf(const char *, size_t);
static char *Allocate(size_t, size_t);
static void Handle(int, siginfo_t *, void *);

extern void CopyWithXmmFault(char *, char *, int);
extern void CopyWithXmm(char *, char *, int);

int main()
{
    struct sigaction sigact;
    int i;


    SigBuf1 = Allocate(SIZE, ALIGN);
    SigBuf2 = Allocate(SIZE, ALIGN);
    for (i = 0; i < SIZE;  i++)
        SigBuf1[i] = (char)i;

    sigact.sa_sigaction = Handle;
    sigact.sa_flags = SA_SIGINFO;
    sigemptyset(&sigact.sa_mask);
    if (sigaction(SIGSEGV, &sigact, 0) == -1)
    {
        fprintf(stderr, "Unable to set up handler\n");
        return 1;
    }
    if (sigaction(SIGBUS, &sigact, 0) == -1)
    {
        fprintf(stderr, "Unable to set up handler\n");
        return 1;
    }

    XmmCheck();
    return 0;
}


static void XmmCheck()
{
    char *p1;
    char *p2;
    int i;

    p1 = Allocate(SIZE, ALIGN);
    p2 = Allocate(SIZE, ALIGN);
    memset(p2, 0, SIZE);

    for (i = 0;  i < SIZE;  i++)
        p1[i] = "abcdefghijklmnopqrstuvwxyz"[i%26];

    /* This routine causes a fault by accessing an illegal memory location */
    CopyWithXmmFault(p2, p1, SIZE);

    /* Verify that the memory was copied correctly */
    CheckBuf(p2, SIZE);
}


static void CheckBuf(const char *p, size_t size)
{
    int i;
    char c;

    for (i = 0;  i < size;  i++)
    {
        c = "abcdefghijklmnopqrstuvwxyz"[i%26];
        if (p[i] != c)
        {
            fprintf(stderr, "Element %d wrong: is '%c' should be '%c'\n", i, p[i], c);
            exit(1);
        }
    }
}


static char *Allocate(size_t size, size_t align)
{
    char *p;
    size_t low;

    p = malloc(size + (align-1));
    low = (size_t)p % align;
    if (low)
        return p + (align-low);
    else
        return p;
}


static void Handle(int sig, siginfo_t *i, void *vctxt)
{
    ucontext_t *ctxt = vctxt;

    /* Fix the illegal memory address access */
#if defined(TARGET_IA32)
#if defined(TARGET_MAC)
    ctxt->uc_mcontext->__ss.__eax = (unsigned long)&Glob;
#else
    ctxt->uc_mcontext.gregs[REG_EAX] = (unsigned long)&Glob;
#endif
#elif defined(TARGET_IA32E)
#if defined(TARGET_BSD)
    ctxt->uc_mcontext.mc_rax = (unsigned long)&Glob;
#elif defined(TARGET_MAC)
    ctxt->uc_mcontext->__ss.__rax = (unsigned long)&Glob;
#else
    ctxt->uc_mcontext.gregs[REG_RAX] = (unsigned long)&Glob;
#endif
#endif

    /* This changes the values of the XMM registers */
    CopyWithXmm(SigBuf2, SigBuf1, SIZE);
}