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/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "git2_util.h"
#if !defined(GIT_WIN32) && !defined(NO_MMAP)
#include "map.h"
#include <sys/mman.h>
#include <unistd.h>
#include <errno.h>
int git__page_size(size_t *page_size)
{
long sc_page_size = sysconf(_SC_PAGE_SIZE);
if (sc_page_size < 0) {
git_error_set(GIT_ERROR_OS, "can't determine system page size");
return -1;
}
*page_size = (size_t) sc_page_size;
return 0;
}
int git__mmap_alignment(size_t *alignment)
{
return git__page_size(alignment);
}
int p_mmap(git_map *out, size_t len, int prot, int flags, int fd, off64_t offset)
{
int mprot = PROT_READ;
int mflag = 0;
GIT_MMAP_VALIDATE(out, len, prot, flags);
out->data = NULL;
out->len = 0;
if (prot & GIT_PROT_WRITE)
mprot |= PROT_WRITE;
if ((flags & GIT_MAP_TYPE) == GIT_MAP_SHARED)
mflag = MAP_SHARED;
else if ((flags & GIT_MAP_TYPE) == GIT_MAP_PRIVATE)
mflag = MAP_PRIVATE;
else
mflag = MAP_SHARED;
out->data = mmap(NULL, len, mprot, mflag, fd, offset);
if (!out->data || out->data == MAP_FAILED) {
git_error_set(GIT_ERROR_OS, "failed to mmap. Could not write data");
return -1;
}
out->len = len;
return 0;
}
int p_munmap(git_map *map)
{
GIT_ASSERT_ARG(map);
munmap(map->data, map->len);
map->data = NULL;
map->len = 0;
return 0;
}
#endif
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