glibc/elf/dl-dst.h

73 lines
3.0 KiB
C

/* Handling of dynamic sring tokens.
Copyright (C) 1999, 2001 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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 2.1 of the License, or (at your option) any later version.
The GNU C Library 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 the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
/* Determine the number of DST elements in the name. Only if IS_PATH is
nonzero paths are recognized (i.e., multiple, ':' separated filenames). */
#define DL_DST_COUNT(name, is_path) \
({ \
size_t __cnt = 0; \
const char *__sf = strchr (name, '$'); \
\
if (__builtin_expect (__sf != NULL, 0)) \
__cnt = _dl_dst_count (__sf, is_path); \
\
__cnt; })
/* Prototype for used function. */
extern size_t _dl_dst_count (const char *name, int is_path);
/* Guess from the number of DSTs the length of the result string. */
#define DL_DST_REQUIRED(l, name, len, cnt) \
({ \
size_t origin_len; \
size_t __len = (len); \
\
/* Now we make a guess how many extra characters on top of the length \
of S we need to represent the result. We know that we have CNT \
replacements. Each at most can use \
MAX (strlen (ORIGIN), strlen (_dl_platform)) \
minus 7 (which is the length of "$ORIGIN"). \
\
First get the origin string if it is not available yet. This can \
only happen for the map of the executable. */ \
if ((l)->l_origin == NULL) \
{ \
assert ((l)->l_name[0] == '\0'); \
(l)->l_origin = _dl_get_origin (); \
origin_len = ((l)->l_origin && (l)->l_origin != (char *) -1 \
? strlen ((l)->l_origin) : 0); \
} \
else \
origin_len = (l)->l_origin == (char *) -1 ? 0 : strlen ((l)->l_origin); \
\
__len + cnt * (MAX (origin_len, _dl_platformlen) - 7); })
/* Find origin of the executable. */
extern const char *_dl_get_origin (void);
/* Perform the DST substitution. */
#define DL_DST_SUBSTITUTE(l, name, res, is_path) \
_dl_dst_substitute (l, name, res, is_path)
/* Prototype for used function. */
extern char *_dl_dst_substitute (struct link_map *l, const char *name,
char *result, int is_path);