1 files changed, 121 insertions, 0 deletions
diff --git a/desktop/unx/source/file_image_unx.c b/desktop/unx/source/file_image_unx.c
new file mode 100644
index 000000000..4294a5761
--- /dev/null
+++ b/desktop/unx/source/file_image_unx.c
@@ -0,0 +1,121 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "file_image.h"
+
+#include <unistd.h>
+
+#include <errno.h>
+#include <fcntl.h>
+
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <string.h>
+
+/*
+ * file_image_open
+ */
+int file_image_open (file_image * image, const char * filename)
+{
+    int         result = 0;
+    int         fd;
+    struct stat st;
+    void *      p;
+
+    if (image == NULL)
+        return EINVAL;
+
+    image->m_base = MAP_FAILED;
+    image->m_size = 0;
+
+    if ((fd = open (filename, O_RDONLY)) == -1)
+        return errno;
+
+    if (fstat (fd, &st) == -1)
+    {
+        result = errno;
+        goto cleanup_and_leave;
+    }
+
+    p = mmap (NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+    if (p == MAP_FAILED)
+    {
+        result = errno;
+        goto cleanup_and_leave;
+    }
+
+    image->m_base = p;
+    image->m_size = st.st_size;
+
+cleanup_and_leave:
+    close (fd);
+    return result;
+}
+
+/*
+ * file_image_pagein.
+ */
+int file_image_pagein (file_image * image)
+{
+    long s = -1;
+    volatile char c =0;
+    size_t idx;
+
+    if (image == NULL)
+        return EINVAL;
+    if (image->m_base == NULL)
+        return EINVAL;
+    if (image->m_size == 0)
+        return 0;
+
+    if (madvise (image->m_base, image->m_size, MADV_WILLNEED) == -1)
+        return errno;
+
+    s = sysconf (_SC_PAGESIZE);
+    if (s == -1)
+        s = 0x1000;
+    // force touching of each page despite the optimizer
+    for(idx = 0; idx < image->m_size; idx += (size_t)s)
+    {
+        c ^= ((volatile const char*)(image->m_base))[idx];
+    }
+    c ^= ((volatile const char*)(image->m_base))[image->m_size-1];
+    (void)c; // silence Clang 13 trunk -Wunused-but-set-variable
+
+    return 0;
+}
+
+/*
+ * file_image_close
+ */
+int file_image_close (file_image * image)
+{
+    if (image == NULL)
+        return EINVAL;
+
+    if (munmap (image->m_base, image->m_size) == -1)
+        return errno;
+
+    image->m_base = NULL;
+    image->m_size = 0;
+    return 0;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */