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/* Information collection during ld.so startup.
Copyright (C) 1995-2020 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, see
<https://www.gnu.org/licenses/>. */
#ifndef _DL_MAIN
#define _DL_MAIN
#include <ldsodefs.h>
#include <limits.h>
#include <stdlib.h>
/* Length limits for names and paths, to protect the dynamic linker,
particularly when __libc_enable_secure is active. */
#ifdef NAME_MAX
# define SECURE_NAME_LIMIT NAME_MAX
#else
# define SECURE_NAME_LIMIT 255
#endif
#ifdef PATH_MAX
# define SECURE_PATH_LIMIT PATH_MAX
#else
# define SECURE_PATH_LIMIT 1024
#endif
/* Strings containing colon-separated lists of audit modules. */
struct audit_list
{
/* Array of strings containing colon-separated path lists. Each
audit module needs its own namespace, so pre-allocate the largest
possible list. */
const char *audit_strings[DL_NNS];
/* Number of entries added to audit_strings. */
size_t length;
/* Index into the audit_strings array (for the iteration phase). */
size_t current_index;
/* Tail of audit_strings[current_index] which still needs
processing. */
const char *current_tail;
/* Scratch buffer for returning a name which is part of the strings
in audit_strings. */
char fname[SECURE_NAME_LIMIT];
};
/* This is a list of all the modes the dynamic loader can be in. */
enum rtld_mode
{
rtld_mode_normal, rtld_mode_list, rtld_mode_verify, rtld_mode_trace,
rtld_mode_help,
};
/* Aggregated state information extracted from environment variables
and the ld.so command line. */
struct dl_main_state
{
struct audit_list audit_list;
/* The library search path. */
const char *library_path;
/* Where library_path comes from. LD_LIBRARY_PATH or --library-path. */
const char *library_path_source;
/* The list preloaded objects from LD_PRELOAD. */
const char *preloadlist;
/* The preload list passed as a command argument. */
const char *preloadarg;
/* Additional glibc-hwcaps subdirectories to search first.
Colon-separated list. */
const char *glibc_hwcaps_prepend;
/* Mask for the internal glibc-hwcaps subdirectories.
Colon-separated list. */
const char *glibc_hwcaps_mask;
enum rtld_mode mode;
/* True if any of the debugging options is enabled. */
bool any_debug;
/* True if information about versions has to be printed. */
bool version_info;
};
/* Helper function to invoke _dl_init_paths with the right arguments
from *STATE. */
static inline void
call_init_paths (const struct dl_main_state *state)
{
_dl_init_paths (state->library_path, state->library_path_source,
state->glibc_hwcaps_prepend, state->glibc_hwcaps_mask);
}
/* Print ld.so usage information and exit. */
_Noreturn void _dl_usage (const char *argv0, const char *wrong_option)
attribute_hidden;
/* Print ld.so version information and exit. */
_Noreturn void _dl_version (void) attribute_hidden;
/* Print ld.so --help output and exit. */
_Noreturn void _dl_help (const char *argv0, struct dl_main_state *state)
attribute_hidden;
#endif /* _DL_MAIN */
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