xref: /freebsd/cddl/contrib/opensolaris/common/ctf/ctf_util.c (revision ebacd8013fe5f7fdf9f6a5b286f6680dd2891036)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <ctf_impl.h>
30 
31 /*
32  * Simple doubly-linked list append routine.  This implementation assumes that
33  * each list element contains an embedded ctf_list_t as the first member.
34  * An additional ctf_list_t is used to store the head (l_next) and tail
35  * (l_prev) pointers.  The current head and tail list elements have their
36  * previous and next pointers set to NULL, respectively.
37  */
38 void
39 ctf_list_append(ctf_list_t *lp, void *new)
40 {
41 	ctf_list_t *p = lp->l_prev;	/* p = tail list element */
42 	ctf_list_t *q = new;		/* q = new list element */
43 
44 	lp->l_prev = q;
45 	q->l_prev = p;
46 	q->l_next = NULL;
47 
48 	if (p != NULL)
49 		p->l_next = q;
50 	else
51 		lp->l_next = q;
52 }
53 
54 /*
55  * Prepend the specified existing element to the given ctf_list_t.  The
56  * existing pointer should be pointing at a struct with embedded ctf_list_t.
57  */
58 void
59 ctf_list_prepend(ctf_list_t *lp, void *new)
60 {
61 	ctf_list_t *p = new;		/* p = new list element */
62 	ctf_list_t *q = lp->l_next;	/* q = head list element */
63 
64 	lp->l_next = p;
65 	p->l_prev = NULL;
66 	p->l_next = q;
67 
68 	if (q != NULL)
69 		q->l_prev = p;
70 	else
71 		lp->l_prev = p;
72 }
73 
74 /*
75  * Delete the specified existing element from the given ctf_list_t.  The
76  * existing pointer should be pointing at a struct with embedded ctf_list_t.
77  */
78 void
79 ctf_list_delete(ctf_list_t *lp, void *existing)
80 {
81 	ctf_list_t *p = existing;
82 
83 	if (p->l_prev != NULL)
84 		p->l_prev->l_next = p->l_next;
85 	else
86 		lp->l_next = p->l_next;
87 
88 	if (p->l_next != NULL)
89 		p->l_next->l_prev = p->l_prev;
90 	else
91 		lp->l_prev = p->l_prev;
92 }
93 
94 /*
95  * Convert an encoded CTF string name into a pointer to a C string by looking
96  * up the appropriate string table buffer and then adding the offset.
97  */
98 const char *
99 ctf_strraw(const ctf_file_t *fp, uint_t name)
100 {
101 	const ctf_strs_t *ctsp = &fp->ctf_str[CTF_NAME_STID(name)];
102 
103 	if (ctsp->cts_strs != NULL && CTF_NAME_OFFSET(name) < ctsp->cts_len)
104 		return (ctsp->cts_strs + CTF_NAME_OFFSET(name));
105 
106 	/* string table not loaded or corrupt offset */
107 	return (NULL);
108 }
109 
110 const char *
111 ctf_strptr(const ctf_file_t *fp, uint_t name)
112 {
113 	const char *s = ctf_strraw(fp, name);
114 	return (s != NULL ? s : "(?)");
115 }
116 
117 /*
118  * Same strdup(3C), but use ctf_alloc() to do the memory allocation.
119  */
120 char *
121 ctf_strdup(const char *s1)
122 {
123 	char *s2 = ctf_alloc(strlen(s1) + 1);
124 
125 	if (s2 != NULL)
126 		(void) strcpy(s2, s1);
127 
128 	return (s2);
129 }
130 
131 /*
132  * Store the specified error code into errp if it is non-NULL, and then
133  * return NULL for the benefit of the caller.
134  */
135 ctf_file_t *
136 ctf_set_open_errno(int *errp, int error)
137 {
138 	if (errp != NULL)
139 		*errp = error;
140 	return (NULL);
141 }
142 
143 /*
144  * Store the specified error code into the CTF container, and then return
145  * CTF_ERR for the benefit of the caller.
146  */
147 long
148 ctf_set_errno(ctf_file_t *fp, int err)
149 {
150 	fp->ctf_errno = err;
151 	return (CTF_ERR);
152 }
153