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
138
139
140
141
142
143
144
145
|
/* $Id: kLdr.c 29 2009-07-01 20:30:29Z bird $ */
/** @file
* kLdr - The Dynamic Loader.
*/
/*
* Copyright (c) 2006-2007 Knut St. Osmundsen <bird-kStuff-spamix@anduin.net>
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/** @mainpage kLdr - The Dynamic Loader
*
* The purpose of kLdr is to provide a generic interface for querying
* information about and loading executable image modules.
*
* kLdr defines the term executable image to include all kinds of files that contains
* binary code that can be executed on a CPU - linker objects (OBJs/Os), shared
* objects (SOs), dynamic link libraries (DLLs), executables (EXEs), and all kinds
* of kernel modules / device drivers (SYSs).
*
* kLdr provides two types of services:
* -# Inspect or/and load individual modules (kLdrMod).
* -# Work as a dynamic loader - construct and maintain an address space (kLdrDy).
*
* The kLdrMod API works on KLDRMOD structures where all the internals are exposed, while
* the kLdrDy API works opque KLDRDY structures. KLDRDY are in reality simple wrappers
* around KLDRMOD with some extra linking and attributes.
*
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#include <k/kLdr.h>
#include "kLdrInternal.h"
/*******************************************************************************
* Global Variables *
*******************************************************************************/
/** Flag indicating whether we've initialized the loader or not.
*
* 0 if not initialized.
* -1 if we're initializing or terminating.
* 1 if we've successfully initialized it.
* -2 if initialization failed.
*/
static int volatile g_fInitialized;
/**
* Initializes the loader.
* @returns 0 on success, non-zero OS status code on failure.
*/
int kldrInit(void)
{
int rc;
/* check we're already good. */
if (g_fInitialized == 1)
return 0;
/* a tiny serialization effort. */
for (;;)
{
if (g_fInitialized == 1)
return 0;
if (g_fInitialized == -2)
return -1;
/** @todo atomic test and set if we care. */
if (g_fInitialized == 0)
{
g_fInitialized = -1;
break;
}
kHlpSleep(1);
}
/*
* Do the initialization.
*/
rc = kHlpHeapInit();
if (!rc)
{
rc = kLdrDyldSemInit();
if (!rc)
{
rc = kldrDyldInit();
if (!rc)
{
g_fInitialized = 1;
return 0;
}
kLdrDyldSemTerm();
}
kHlpHeapTerm();
}
g_fInitialized = -2;
return rc;
}
/**
* Terminates the loader.
*/
void kldrTerm(void)
{
/* can't terminate unless it's initialized. */
if (g_fInitialized != 1)
return;
g_fInitialized = -1;
/*
* Do the termination.
*/
kLdrDyldSemTerm();
kHlpHeapTerm();
/* done */
g_fInitialized = 0;
}
|
