mono/utils/mono-filemap.c

   1 /*
   2  * mono-filemap.c: Unix/Windows implementation for filemap.
   3  *
   4  * Author:
   5  *   Paolo Molaro (lupus@ximian.com)
   6  *
   7  * Copyright 2008-2008 Novell, Inc.
   8  */
   9
  10 #include "config.h"
  11
  12 #if HAVE_SYS_STAT_H
  13 #include <sys/stat.h>
  14 #endif
  15 #include <fcntl.h>
  16 #include <string.h>
  17 #ifdef HAVE_UNISTD_H
  18 #include <unistd.h>
  19 #endif
  20 #include <stdlib.h>
  21 #include <stdio.h>
  22
  23 #include "mono-mmap.h"
  24
  25 MonoFileMap *
  26 mono_file_map_open (const char* name)
  27 {
  28         return (MonoFileMap *)fopen (name, "rb");
  29 }
  30
  31 guint64
  32 mono_file_map_size (MonoFileMap *fmap)
  33 {
  34         struct stat stat_buf;
  35         if (fstat (fileno ((FILE*)fmap), &stat_buf) < 0)
  36                 return 0;
  37         return stat_buf.st_size;
  38 }
  39
  40 int
  41 mono_file_map_fd (MonoFileMap *fmap)
  42 {
  43         return fileno ((FILE*)fmap);
  44 }
  45
  46 int
  47 mono_file_map_close (MonoFileMap *fmap)
  48 {
  49         return fclose ((FILE*)fmap);
  50 }
  51
  52 #if !defined(HAVE_MMAP) && !defined (HOST_WIN32)
  53
  54 static mono_file_map_alloc_fn alloc_fn = (mono_file_map_alloc_fn) malloc;
  55 static mono_file_map_release_fn release_fn = (mono_file_map_release_fn) free;
  56
  57 void
  58 mono_file_map_set_allocator (mono_file_map_alloc_fn alloc, mono_file_map_release_fn release)
  59 {
  60         alloc_fn = alloc == NULL     ? (mono_file_map_alloc_fn) malloc : alloc;
  61         release_fn = release == NULL ? (mono_file_map_release_fn) free : release;
  62 }
  63
  64 void *
  65 mono_file_map (size_t length, int flags, int fd, guint64 offset, void **ret_handle)
  66 {
  67         guint64 cur_offset;
  68         size_t bytes_read;
  69         void *ptr = (*alloc_fn) (length);
  70         if (!ptr)
  71                 return NULL;
  72         cur_offset = lseek (fd, 0, SEEK_CUR);
  73         if (lseek (fd, offset, SEEK_SET) != offset) {
  74                 free (ptr);
  75                 return NULL;
  76         }
  77         bytes_read = read (fd, ptr, length);
  78         lseek (fd, cur_offset, SEEK_SET);
  79         *ret_handle = NULL;
  80         return ptr;
  81 }
  82
  83 int
  84 mono_file_unmap (void *addr, void *handle)
  85 {
  86         (*release_fn) (addr);
  87         return 0;
  88 }
  89 #endif