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/* Error handling for runtime dynamic linker.
Copyright (C) 1995, 1996, 1997, 1998, 1999 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <setjmp.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <elf/ldsodefs.h>
#include <bits/libc-tsd.h>
/* This structure communicates state between _dl_catch_error and
_dl_signal_error. */
struct catch
{
char *errstring; /* Error detail filled in here. */
jmp_buf env; /* longjmp here on error. */
};
/* Multiple threads at once can use the `_dl_catch_error' function. The
calls can come from `_dl_map_object_deps', `_dlerror_run', or from
any of the libc functionality which loads dynamic objects (NSS, iconv).
Therefore we have to be prepared to save the state in thread-local
memory. */
__libc_tsd_define (static, DL_ERROR)
#define tsd_getspecific() __libc_tsd_get (DL_ERROR)
#define tsd_setspecific(data) __libc_tsd_set (DL_ERROR, (data))
/* This points to a function which is called when an continuable error is
received. Unlike the handling of `catch' this function may return.
The arguments will be the `errstring' and `objname'.
Since this functionality is not used in normal programs (only in ld.so)
we do not care about multi-threaded programs here. We keep this as a
global variable. */
static receiver_fct receiver;
void
internal_function
_dl_signal_error (int errcode,
const char *objname,
const char *errstring)
{
struct catch *lcatch;
if (! errstring)
errstring = "DYNAMIC LINKER BUG!!!";
lcatch = tsd_getspecific ();
if (lcatch != NULL)
{
/* We are inside _dl_catch_error. Return to it. We have to
duplicate the error string since it might be allocated on the
stack. */
size_t objname_len = objname ? strlen (objname) + 2 : 0;
size_t errstring_len = strlen (errstring) + 1;
lcatch->errstring = malloc (objname_len + errstring_len);
if (lcatch->errstring != NULL)
{
char *cp = lcatch->errstring;
if (objname_len > 0)
{
cp = __mempcpy (cp, objname, objname_len - 2);
cp = __mempcpy (cp, ": ", 2);
}
memcpy (cp, errstring, errstring_len);
}
longjmp (lcatch->env, errcode ?: -1);
}
else
{
/* Lossage while resolving the program's own symbols is always fatal. */
char buffer[1024];
_dl_sysdep_fatal (_dl_argv[0] ?: "<program name unknown>",
": error while loading shared libraries: ",
objname ?: "", objname && *objname ? ": " : "",
errstring, errcode ? ": " : "",
(errcode
? __strerror_r (errcode, buffer, sizeof buffer)
: ""), "\n", NULL);
}
}
void
internal_function
_dl_signal_cerror (int errcode,
const char *objname,
const char *errstring)
{
if (receiver)
{
/* We are inside _dl_receive_error. Call the user supplied
handler and resume the work. The receiver will still be
installed. */
(*receiver) (errcode, objname, errstring);
}
else
_dl_signal_error (errcode, objname, errstring);
}
int
internal_function
_dl_catch_error (char **errstring,
void (*operate) (void *),
void *args)
{
int errcode;
struct catch *volatile old;
struct catch c;
/* We need not handle `receiver' since setting a `catch' is handled
before it. */
/* Some systems (e.g., SPARC) handle constructors to local variables
inefficient. So we initialize `c' by hand. */
c.errstring = NULL;
old = tsd_getspecific ();
errcode = setjmp (c.env);
if (errcode == 0)
{
tsd_setspecific (&c);
(*operate) (args);
tsd_setspecific (old);
*errstring = NULL;
return 0;
}
/* We get here only if we longjmp'd out of OPERATE. */
tsd_setspecific (old);
*errstring = c.errstring;
return errcode == -1 ? 0 : errcode;
}
void
internal_function
_dl_receive_error (receiver_fct fct, void (*operate) (void *), void *args)
{
struct catch *old_catch;
receiver_fct old_receiver;
old_catch = tsd_getspecific ();
old_receiver = receiver;
/* Set the new values. */
tsd_setspecific (NULL);
receiver = fct;
(*operate) (args);
tsd_setspecific (old_catch);
receiver = old_receiver;
}
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