1 /* Copyright (C) 1989, 1990, 1991, 1992, 2000, 2001, 2004
2    Free Software Foundation, Inc.
3      Written by James Clark (jjc@jclark.com)
4 
5 This file is part of groff.
6 
7 groff is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
11 
12 groff is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15 for more details.
16 
17 You should have received a copy of the GNU General Public License along
18 with groff; see the file COPYING.  If not, write to the Free Software
19 Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA. */
20 
21 #include <stdlib.h>
22 
23 #ifdef HAVE_CONFIG_H
24 #include <config.h>
25 #endif
26 
27 #ifdef HAVE_MMAP
28 
29 #include <sys/types.h>
30 #include <sys/mman.h>
31 
32 /* The Net-2 man pages says that a MAP_FILE flag is required. */
33 #ifndef MAP_FILE
34 #define MAP_FILE 0
35 #endif
36 
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40 
mapread(int fd,int nbytes)41 char *mapread(int fd, int nbytes)
42 {
43   char *p = (char *)mmap((void *)0, (size_t)nbytes, PROT_READ,
44 			 MAP_FILE|MAP_PRIVATE, fd, (off_t)0);
45   if (p == (char *)-1)
46     return 0;
47   /* mmap() shouldn't return 0 since MAP_FIXED wasn't specified. */
48   if (p == 0)
49     abort();
50   return p;
51 }
52 
unmap(char * p,int len)53 int unmap(char *p, int len)
54 {
55   return munmap((void *)p, len);
56 }
57 
58 #ifdef __cplusplus
59 }
60 #endif
61 
62 #else /* not HAVE_MMAP */
63 
64 #include <errno.h>
65 
66 #ifdef __cplusplus
67 extern "C" {
68 #endif
69 
mapread(int fd,int nbytes)70 char *mapread(int fd, int nbytes)
71 {
72   errno = ENODEV;
73   return 0;
74 }
75 
unmap(char * p,int len)76 int unmap(char *p, int len)
77 {
78   errno = EINVAL;
79   return -1;
80 }
81 
82 #ifdef __cplusplus
83 }
84 #endif
85 
86 #endif /* not HAVE_MMAP */
87