[glibc.git] / elf / dl-error.c

/* Error handling for runtime dynamic linker.
Copyright (C) 1995, 1996 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., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <stddef.h>
#include <link.h>
#include <setjmp.h>
#include <string.h>

/* This structure communicates state between _dl_catch_error and
   _dl_signal_error.  */
struct catch
  {
    const char *errstring, *objname; /* Error detail filled in here.  */
    jmp_buf env;		/* longjmp here on error.  */
  };

/* This points to such a structure during a call to _dl_catch_error.
   During implicit startup and run-time work for needed shared libraries,
   this is null.  */
static struct catch *catch;


void
_dl_signal_error (int errcode,
		  const char *objname,
		  const char *errstring)
{
  if (! errstring)
    errstring = "DYNAMIC LINKER BUG!!!";

  if (catch)
    {
      /* 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 len = strlen (errstring) + 1;
      catch->errstring = malloc (len);
      if (catch->errstring != NULL)
	memcpy (catch->errstring, errstring, len);
      catch->objname = objname;
      longjmp (catch->env, errcode ?: -1);
    }
  else
    {
      /* Lossage while resolving the program's own symbols is always fatal.  */
      extern char **_dl_argv;	/* Set in rtld.c at startup.  */
      _dl_sysdep_fatal (_dl_argv[0] ?: "<program name unknown>",
			": error in loading shared libraries\n",
			objname ?: "", objname ? ": " : "",
			errstring, errcode ? ": " : "",
			errcode ? strerror (errcode) : "", "\n", NULL);
    }
}

int
_dl_catch_error (const char **errstring,
		 const char **objname,
		 void (*operate) (void))
{
  int errcode;
  struct catch c = { errstring: NULL, objname: NULL };

  errcode = setjmp (c.env);
  if (errcode == 0)
    {
      catch = &c;
      (*operate) ();
      catch = NULL;
      *errstring = *objname = NULL;
      return 0;
    }

  /* We get here only if we longjmp'd out of OPERATE.  */
  *errstring = c.errstring;
  *objname = c.objname;
  return errcode == -1 ? 0 : errcode;
}
Commit	Line	Data
	1	/* Error handling for runtime dynamic linker.
	2	Copyright (C) 1995, 1996 Free Software Foundation, Inc.
	3	This file is part of the GNU C Library.
	4
	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Library General Public License as
	7	published by the Free Software Foundation; either version 2 of the
	8	License, or (at your option) any later version.
	9
	10	The GNU C Library 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 the GNU C Library; see the file COPYING.LIB. If
	17	not, write to the Free Software Foundation, Inc., 675 Mass Ave,
	18	Cambridge, MA 02139, USA. */
	19
	20	#include <stddef.h>
	21	#include <link.h>
	22	#include <setjmp.h>
	23	#include <string.h>
	24
	25	/* This structure communicates state between _dl_catch_error and
	26	_dl_signal_error. */
	27	struct catch
	28	{
	29	const char errstring, objname; /* Error detail filled in here. */
	30	jmp_buf env; /* longjmp here on error. */
	31	};
	32
	33	/* This points to such a structure during a call to _dl_catch_error.
	34	During implicit startup and run-time work for needed shared libraries,
	35	this is null. */
	36	static struct catch *catch;
	37
	38
	39	void
	40	_dl_signal_error (int errcode,
	41	const char *objname,
	42	const char *errstring)
	43	{
	44	if (! errstring)
	45	errstring = "DYNAMIC LINKER BUG!!!";
	46
	47	if (catch)
	48	{
	49	/* We are inside _dl_catch_error. Return to it. We have to
	50	duplicate the error string since it might be allocated on the
	51	stack. */
	52	size_t len = strlen (errstring) + 1;
	53	catch->errstring = malloc (len);
	54	if (catch->errstring != NULL)
	55	memcpy (catch->errstring, errstring, len);
	56	catch->objname = objname;
	57	longjmp (catch->env, errcode ?: -1);
	58	}
	59	else
	60	{
	61	/* Lossage while resolving the program's own symbols is always fatal. */
	62	extern char *_dl_argv; / Set in rtld.c at startup. */
	63	_dl_sysdep_fatal (_dl_argv[0] ?: "<program name unknown>",
	64	": error in loading shared libraries\n",
	65	objname ?: "", objname ? ": " : "",
	66	errstring, errcode ? ": " : "",
	67	errcode ? strerror (errcode) : "", "\n", NULL);
	68	}
	69	}
	70
	71	int
	72	_dl_catch_error (const char **errstring,
	73	const char **objname,
	74	void (*operate) (void))
	75	{
	76	int errcode;
	77	struct catch c = { errstring: NULL, objname: NULL };
	78
	79	errcode = setjmp (c.env);
	80	if (errcode == 0)
	81	{
	82	catch = &c;
	83	(*operate) ();
	84	catch = NULL;
	85	errstring = objname = NULL;
	86	return 0;
	87	}
	88
	89	/* We get here only if we longjmp'd out of OPERATE. */
	90	*errstring = c.errstring;
	91	*objname = c.objname;
	92	return errcode == -1 ? 0 : errcode;
	93	}