1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1997-2012 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                                                                      *
19 ***********************************************************************/
20 #pragma prototyped
21 /*
22  * Glenn Fowler
23  * AT&T Research
24  */
25 
26 #include "dlllib.h"
27 
28 /*
29  * find and load lib plugin/module library name with optional version ver and dlopen() flags
30  * at least one dlopen() is called to initialize dlerror()
31  * if path!=0 then library path up to size chars copied to path with trailing 0
32  * if name contains a directory prefix then library search is limited to the dir and siblings
33  */
34 
35 extern void*
dllplugin(const char * lib,const char * name,const char * ver,unsigned long rel,unsigned long * cur,int flags,char * path,size_t size)36 dllplugin(const char* lib, const char* name, const char* ver, unsigned long rel, unsigned long* cur, int flags, char* path, size_t size)
37 {
38 	void*		dll;
39 	int		err;
40 	int		hit;
41 	Dllscan_t*	dls;
42 	Dllent_t*	dle;
43 
44 	err = hit = 0;
45 	for (;;)
46 	{
47 		if (dls = dllsopen(lib, name, ver))
48 		{
49 			while (dle = dllsread(dls))
50 			{
51 				hit = 1;
52 #if 0
53 			again:
54 #endif
55 				if (dll = dllopen(dle->path, flags|RTLD_GLOBAL|RTLD_PARENT))
56 				{
57 					if (!dllcheck(dll, dle->path, rel, cur))
58 					{
59 						err = state.error;
60 						dlclose(dll);
61 						dll = 0;
62 						continue;
63 					}
64 					if (path && size)
65 						strlcpy(path, dle->path, size);
66 					break;
67 				}
68 				else
69 				{
70 #if 0
71 					/*
72 					 * dlopen() should load implicit libraries
73 					 * this code does that
74 					 * but it doesn't help on galadriel
75 					 */
76 
77 					char*	s;
78 					char*	e;
79 
80 					if ((s = dllerror(1)) && (e = strchr(s, ':')))
81 					{
82 						*e = 0;
83 						error(1, "AHA %s implicit", s);
84 						dll = dllplugin(lib, s, 0, 0, 0, flags, path, size);
85 						*e = ':';
86 						if (dll)
87 						{
88 							error(1, "AHA implicit %s => %s", s, path);
89 							goto again;
90 						}
91 					}
92 #endif
93 					errorf("dll", NiL, 1, "dllplugin: %s dlopen failed: %s", dle->path, dllerror(1));
94 					err = state.error;
95 				}
96 			}
97 			dllsclose(dls);
98 		}
99 		if (hit)
100 		{
101 			if (!dll)
102 				state.error = err;
103 			return dll;
104 		}
105 		if (!lib)
106 			break;
107 		lib = 0;
108 	}
109 	if (dll = dllopen(name, flags))
110 	{
111 		if (!dllcheck(dll, name, rel, cur))
112 		{
113 			dlclose(dll);
114 			dll = 0;
115 		}
116 		else if (path && size)
117 			strlcpy(path, name, size);
118 	}
119 	return dll;
120 }
121 
122 extern void*
dllplug(const char * lib,const char * name,const char * ver,int flags,char * path,size_t size)123 dllplug(const char* lib, const char* name, const char* ver, int flags, char* path, size_t size)
124 {
125 	return dllplugin(lib, name, ver, 0, NiL, flags, path, size);
126 }
127