1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/* Error handling for runtime dynamic linker.
Copyright (C) 1995, 1996, 1997 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 <stddef.h>
#include <link.h>
#include <setjmp.h>
#include <stdlib.h>
#include <string.h>
/* This structure communicates state between _dl_catch_error and
_dl_signal_error. */
struct catch
{
char *errstring; /* Error detail filled in here. */
const char *objname;
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;
/* This points to a function which is called when an error is
received. Unlike the handling of `catch' this function may return.
The arguments will be the `errstring' and `objname'. */
static receiver_fct receiver;
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 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
{
/* 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 (char **errstring,
const char **objname,
void (*operate) (void *),
void *args)
{
int errcode;
struct catch *old, 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;
c.objname = NULL;
old = catch;
errcode = setjmp (c.env);
if (errcode == 0)
{
catch = &c;
(*operate) (args);
catch = old;
*errstring = NULL;
*objname = NULL;
return 0;
}
/* We get here only if we longjmp'd out of OPERATE. */
catch = old;
*errstring = c.errstring;
*objname = c.objname;
return errcode == -1 ? 0 : errcode;
}
void
_dl_receive_error (receiver_fct fct, void (*operate) (void *), void *args)
{
struct catch *old_catch;
receiver_fct old_receiver;
old_catch = catch;
old_receiver = receiver;
/* Set the new values. */
catch = NULL;
receiver = fct;
(*operate) (args);
catch = old_catch;
receiver = old_receiver;
}
|
