102 lines
3.9 KiB
C
102 lines
3.9 KiB
C
|
/* Provide relocatable packages.
|
||
|
|
Copyright (C) 2003, 2005, 2008-2017 Free Software Foundation, Inc.
|
||
|
|
Written by Bruno Haible <bruno@clisp.org>, 2003.
|
||
|
|
|
||
|
|
This program is free software; you can redistribute it and/or modify it
|
||
|
|
under the terms of the GNU Lesser General Public License as published
|
||
|
|
by the Free Software Foundation; either version 2, or (at your option)
|
||
|
|
any later version.
|
||
|
|
|
||
|
|
This program is distributed in the hope that it will be useful,
|
||
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
|
|
Lesser General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU Lesser General Public License
|
||
|
|
along with this program; if not, see <https://www.gnu.org/licenses/>. */
|
||
|
|
|
||
|
|
#ifndef _RELOCATABLE_H
|
||
|
|
#define _RELOCATABLE_H
|
||
|
|
|
||
|
|
#ifdef __cplusplus
|
||
|
|
extern "C" {
|
||
|
|
#endif
|
||
|
|
|
||
|
|
|
||
|
|
/* This can be enabled through the configure --enable-relocatable option. */
|
||
|
|
#if ENABLE_RELOCATABLE
|
||
|
|
|
||
|
|
/* When building a DLL, we must export some functions. Note that because
|
||
|
|
this is a private .h file, we don't need to use __declspec(dllimport)
|
||
|
|
in any case. */
|
||
|
|
#if HAVE_VISIBILITY && BUILDING_DLL
|
||
|
|
# define RELOCATABLE_DLL_EXPORTED __attribute__((__visibility__("default")))
|
||
|
|
#elif defined _MSC_VER && BUILDING_DLL
|
||
|
|
# define RELOCATABLE_DLL_EXPORTED __declspec(dllexport)
|
||
|
|
#else
|
||
|
|
# define RELOCATABLE_DLL_EXPORTED
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* Sets the original and the current installation prefix of the package.
|
||
|
|
Relocation simply replaces a pathname starting with the original prefix
|
||
|
|
by the corresponding pathname with the current prefix instead. Both
|
||
|
|
prefixes should be directory names without trailing slash (i.e. use ""
|
||
|
|
instead of "/"). */
|
||
|
|
extern RELOCATABLE_DLL_EXPORTED void
|
||
|
|
set_relocation_prefix (const char *orig_prefix,
|
||
|
|
const char *curr_prefix);
|
||
|
|
|
||
|
|
/* Returns the pathname, relocated according to the current installation
|
||
|
|
directory.
|
||
|
|
The returned string is either PATHNAME unmodified or a freshly allocated
|
||
|
|
string that you can free with free() after casting it to 'char *'. */
|
||
|
|
extern const char * relocate (const char *pathname);
|
||
|
|
|
||
|
|
/* Returns the pathname, relocated according to the current installation
|
||
|
|
directory.
|
||
|
|
This function sets *ALLOCATEDP to the allocated memory, or to NULL if
|
||
|
|
no memory allocation occurs. So that, after you're done with the return
|
||
|
|
value, to reclaim allocated memory, you can do: free (*ALLOCATEDP). */
|
||
|
|
extern const char * relocate2 (const char *pathname, char **allocatedp);
|
||
|
|
|
||
|
|
/* Memory management: relocate() potentially allocates memory, because it has
|
||
|
|
to construct a fresh pathname. If this is a problem because your program
|
||
|
|
calls relocate() frequently or because you want to fix all potential memory
|
||
|
|
leaks anyway, you have three options:
|
||
|
|
1) Use this idiom:
|
||
|
|
const char *pathname = ...;
|
||
|
|
const char *rel_pathname = relocate (pathname);
|
||
|
|
...
|
||
|
|
if (rel_pathname != pathname)
|
||
|
|
free ((char *) rel_pathname);
|
||
|
|
2) Use this idiom:
|
||
|
|
char *allocated;
|
||
|
|
const char *rel_pathname = relocate2 (..., &allocated);
|
||
|
|
...
|
||
|
|
free (allocated);
|
||
|
|
3) Think about caching the result. */
|
||
|
|
|
||
|
|
/* Convenience function:
|
||
|
|
Computes the current installation prefix, based on the original
|
||
|
|
installation prefix, the original installation directory of a particular
|
||
|
|
file, and the current pathname of this file.
|
||
|
|
Returns it, freshly allocated. Returns NULL upon failure. */
|
||
|
|
extern char * compute_curr_prefix (const char *orig_installprefix,
|
||
|
|
const char *orig_installdir,
|
||
|
|
const char *curr_pathname);
|
||
|
|
|
||
|
|
#else
|
||
|
|
|
||
|
|
/* By default, we use the hardwired pathnames. */
|
||
|
|
#define relocate(pathname) (pathname)
|
||
|
|
#define relocate2(pathname,allocatedp) (*(allocatedp) = NULL, (pathname))
|
||
|
|
|
||
|
|
#endif
|
||
|
|
|
||
|
|
|
||
|
|
#ifdef __cplusplus
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif /* _RELOCATABLE_H */
|