1/* Provide relocatable packages.
2   Copyright (C) 2003 Free Software Foundation, Inc.
3   Written by Bruno Haible <bruno@clisp.org>, 2003.
4
5   This program is free software; you can redistribute it and/or modify it
6   under the terms of the GNU Library General Public License as published
7   by the Free Software Foundation; either version 2, or (at your option)
8   any later version.
9
10   This program is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Library General Public License for more details.
14
15   You should have received a copy of the GNU Library General Public
16   License along with this program; if not, write to the Free Software
17   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
18   USA.  */
19
20#ifndef _RELOCATABLE_H
21#define _RELOCATABLE_H
22
23#ifdef __cplusplus
24extern "C" {
25#endif
26
27
28/* This can be enabled through the configure --enable-relocatable option.  */
29#if ENABLE_RELOCATABLE
30
31/* When building a DLL, we must export some functions.  Note that because
32   this is a private .h file, we don't need to use __declspec(dllimport)
33   in any case.  */
34#if defined _MSC_VER && BUILDING_DLL
35# define RELOCATABLE_DLL_EXPORTED __declspec(dllexport)
36#else
37# define RELOCATABLE_DLL_EXPORTED
38#endif
39
40/* Sets the original and the current installation prefix of the package.
41   Relocation simply replaces a pathname starting with the original prefix
42   by the corresponding pathname with the current prefix instead.  Both
43   prefixes should be directory names without trailing slash (i.e. use ""
44   instead of "/").  */
45extern RELOCATABLE_DLL_EXPORTED void
46       set_relocation_prefix (const char *orig_prefix,
47			      const char *curr_prefix);
48
49/* Returns the pathname, relocated according to the current installation
50   directory.  */
51extern const char * relocate (const char *pathname);
52
53/* Memory management: relocate() leaks memory, because it has to construct
54   a fresh pathname.  If this is a problem because your program calls
55   relocate() frequently, think about caching the result.  */
56
57/* Convenience function:
58   Computes the current installation prefix, based on the original
59   installation prefix, the original installation directory of a particular
60   file, and the current pathname of this file.  Returns NULL upon failure.  */
61extern const char * compute_curr_prefix (const char *orig_installprefix,
62					 const char *orig_installdir,
63					 const char *curr_pathname);
64
65#else
66
67/* By default, we use the hardwired pathnames.  */
68#define relocate(pathname) (pathname)
69
70#endif
71
72
73#ifdef __cplusplus
74}
75#endif
76
77#endif /* _RELOCATABLE_H */
78