/* Alloc.c -- Memory allocation functions
2008-09-24
Igor Pavlov
Public domain */

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

#ifdef _7ZIP_LARGE_PAGES

#ifdef __linux__

#ifndef _7ZIP_ST
#include <pthread.h>
#endif
#include <unistd.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/mman.h>
#include <fcntl.h>

#ifndef SHM_HUGETLB
#warning SHM_HUGETLB undefined ?
#define SHM_HUGETLB 04000
#endif

/* Only ia64 requires this */
#ifdef __ia64__
#define ADDR (void *)(0x8000000000000000UL)
#define SHMAT_FLAGS (SHM_RND)
#else
#define ADDR (void *)(0x0UL)
#define SHMAT_FLAGS (0)
#endif


#endif /*  __linux__ */

#endif /* _7ZIP_LARGE_PAGES */

#include "Alloc.h"

/* #define _SZ_ALLOC_DEBUG */

/* use _SZ_ALLOC_DEBUG to debug alloc/free operations */
#ifdef _SZ_ALLOC_DEBUG
#include <stdio.h>
int g_allocCount = 0;
int g_allocCountMid = 0;
int g_allocCountBig = 0;
#endif

void *MyAlloc(size_t size)
{
  if (size == 0)
    return 0;
  #ifdef _SZ_ALLOC_DEBUG
  {
    void *p = malloc(size);
    fprintf(stderr, "\nAlloc %10d bytes, count = %10d,  addr = %8X", size, g_allocCount++, (unsigned)p);
    return p;
  }
  #else
  return malloc(size);
  #endif
}

void MyFree(void *address)
{
  #ifdef _SZ_ALLOC_DEBUG
  if (address != 0)
    fprintf(stderr, "\nFree; count = %10d,  addr = %8X", --g_allocCount, (unsigned)address);
  #endif
  free(address);
}

#ifdef __linux__
#define _7ZIP_MAX_HUGE_ALLOCS 64
static void *g_HugePageAddr[_7ZIP_MAX_HUGE_ALLOCS] = { NULL };
static void *g_HugePageShmid[_7ZIP_MAX_HUGE_ALLOCS];
static size_t g_HugePageLen[_7ZIP_MAX_HUGE_ALLOCS];
#endif

static void *VirtualAlloc(void *address, size_t size, int AllocLargePages)
{
  #ifdef _7ZIP_LARGE_PAGES
  if (AllocLargePages)
  {
    #ifdef __linux__
    /* huge pages support for Linux; added by Joachim Henke */
    #ifndef _7ZIP_ST
    static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
    #endif
    int i;

    address = NULL;
    #ifndef _7ZIP_ST
    pthread_mutex_lock(&mutex);
    #endif
    for (i = 0; i < _7ZIP_MAX_HUGE_ALLOCS; ++i)
    {
      if (g_HugePageAddr[i] == NULL)
      {
        char *shmaddr;
        int shmid = shmget(2, size, SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
        if (shmid < 0)
        {
          fprintf(stderr,"Warning shmget : %s\n",strerror(errno));
          address = NULL;
          break;
        }
        shmaddr = shmat(shmid, ADDR, SHMAT_FLAGS);
        if (shmaddr == (char *)-1)
        {
          fprintf(stderr,"Warning shmat : %s\n",strerror(errno));
          shmctl(shmid, IPC_RMID, NULL);
          address = NULL;
          break;
        }
        
        g_HugePageShmid[i] = shmid;
        g_HugePageLen[i] = size;
        g_HugePageAddr[i] = address;
printf("HUGE[%d]=%ld %p\n",i,(long)size,address);
        break;
      }
    }
    #ifndef _7ZIP_ST
    pthread_mutex_unlock(&mutex);
    #endif
    return address;
    #endif
  }
  #endif
  return malloc(size);
}

static int VirtualFree(void *address)
{
  #ifdef _7ZIP_LARGE_PAGES
  #ifdef __linux__
  int i;

  for (i = 0; i < _7ZIP_MAX_HUGE_ALLOCS; ++i)
  {
    if (g_HugePageAddr[i] == address)
    {
      shmdt(g_HugePageAddr[i]);
      shmctl(g_HugePageLen[i], IPC_RMID, NULL);
      g_HugePageAddr[i] = NULL;
      return 1;
    }
  }
  #endif
  #endif
  free(address);
  return 1;
}

void *MidAlloc(size_t size)
{
  if (size == 0)
    return 0;
  #ifdef _SZ_ALLOC_DEBUG
  fprintf(stderr, "\nAlloc_Mid %10d bytes;  count = %10d", size, g_allocCountMid++);
  #endif
  return VirtualAlloc(0, size, 0);
}

void MidFree(void *address)
{
  #ifdef _SZ_ALLOC_DEBUG
  if (address != 0)
    fprintf(stderr, "\nFree_Mid; count = %10d", --g_allocCountMid);
  #endif
  if (address == 0)
    return;
  VirtualFree(address);
}

#ifdef _7ZIP_LARGE_PAGES
size_t g_LargePageSize = 0;
#endif

void SetLargePageSize()
{
printf("SetLargePageSize : <>\n");
  #ifdef _7ZIP_LARGE_PAGES
  size_t size = 0;

#if defined(__linux__)
  size = sysconf(_SC_PAGESIZE);
printf("SetLargePageSize : size=%ld\n",(long)size);
  if (size == -1) size = 0;
#endif

  if (size == 0 || (size & (size - 1)) != 0)
    return;
  g_LargePageSize = size;
printf("SetLargePageSize : %ld\n",(long)g_LargePageSize);
  #endif
}


void *BigAlloc(size_t size)
{
  if (size == 0)
    return 0;
  #ifdef _SZ_ALLOC_DEBUG
  fprintf(stderr, "\nAlloc_Big %10d bytes;  count = %10d", size, g_allocCountBig++);
  #endif
  
  #ifdef _7ZIP_LARGE_PAGES
  if (g_LargePageSize != 0 && g_LargePageSize <= (1 << 30) && size >= (1 << 18))
  {
    void *res = VirtualAlloc(0, (size + g_LargePageSize - 1) & (~(g_LargePageSize - 1)),1);
printf("BigAlloc : %ld %ld => %p\n",(long)g_LargePageSize,(long)size,res);
    if (res != 0)
      return res;
  }
  #endif
  return VirtualAlloc(0, size, 0);
}

void BigFree(void *address)
{
  #ifdef _SZ_ALLOC_DEBUG
  if (address != 0)
    fprintf(stderr, "\nFree_Big; count = %10d", --g_allocCountBig);
  #endif
  
  if (address == 0)
    return;
  VirtualFree(address);
}