xref: /illumos-gate/usr/src/common/ctf/ctf_labels.c (revision 8b80e8cb6855118d46f605e91b5ed4ce83417395)
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 2002-2003 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 static int
32 extract_label_info(ctf_file_t *fp, const ctf_lblent_t **ctl, uint_t *num_labels)
33 {
34 	const ctf_header_t *h;
35 
36 	/*
37 	 * Labels are only supported in V2 or later
38 	 */
39 	if (fp->ctf_version < CTF_VERSION_2)
40 		return (ctf_set_errno(fp, ECTF_NOTSUP));
41 
42 	h = (const ctf_header_t *)fp->ctf_data.cts_data;
43 
44 	/* LINTED - pointer alignment */
45 	*ctl = (const ctf_lblent_t *)(fp->ctf_buf + h->cth_lbloff);
46 	*num_labels = (h->cth_objtoff - h->cth_lbloff) / sizeof (ctf_lblent_t);
47 
48 	return (0);
49 }
50 
51 /*
52  * Returns the topmost label, or NULL if any errors are encountered
53  */
54 const char *
55 ctf_label_topmost(ctf_file_t *fp)
56 {
57 	const ctf_lblent_t *ctlp;
58 	const char *s;
59 	uint_t num_labels;
60 
61 	if (extract_label_info(fp, &ctlp, &num_labels) == CTF_ERR)
62 		return (NULL); /* errno is set */
63 
64 	if (num_labels == 0) {
65 		(void) ctf_set_errno(fp, ECTF_NOLABELDATA);
66 		return (NULL);
67 	}
68 
69 	if ((s = ctf_strraw(fp, (ctlp + num_labels - 1)->ctl_label)) == NULL)
70 		(void) ctf_set_errno(fp, ECTF_CORRUPT);
71 
72 	return (s);
73 }
74 
75 /*
76  * Iterate over all labels.  We pass the label string and the lblinfo_t struct
77  * to the specified callback function.
78  */
79 int
80 ctf_label_iter(ctf_file_t *fp, ctf_label_f *func, void *arg)
81 {
82 	const ctf_lblent_t *ctlp;
83 	uint_t i, num_labels;
84 	ctf_lblinfo_t linfo;
85 	const char *lname;
86 	int rc;
87 
88 	if (extract_label_info(fp, &ctlp, &num_labels) == CTF_ERR)
89 		return (CTF_ERR); /* errno is set */
90 
91 	if (num_labels == 0)
92 		return (ctf_set_errno(fp, ECTF_NOLABELDATA));
93 
94 	for (i = 0; i < num_labels; i++, ctlp++) {
95 		if ((lname = ctf_strraw(fp, ctlp->ctl_label)) == NULL) {
96 			ctf_dprintf("failed to decode label %u with "
97 			    "typeidx %u\n", ctlp->ctl_label, ctlp->ctl_typeidx);
98 			return (ctf_set_errno(fp, ECTF_CORRUPT));
99 		}
100 
101 		linfo.ctb_typeidx = ctlp->ctl_typeidx;
102 		if ((rc = func(lname, &linfo, arg)) != 0)
103 			return (rc);
104 	}
105 
106 	return (0);
107 }
108 
109 typedef struct linfo_cb_arg {
110 	const char *lca_name;    /* Label we want to retrieve info for */
111 	ctf_lblinfo_t *lca_info; /* Where to store the info about the label */
112 } linfo_cb_arg_t;
113 
114 static int
115 label_info_cb(const char *lname, const ctf_lblinfo_t *linfo, void *arg)
116 {
117 	/*
118 	 * If lname matches the label we are looking for, copy the
119 	 * lblinfo_t struct for the caller.
120 	 */
121 	if (strcmp(lname, ((linfo_cb_arg_t *)arg)->lca_name) == 0) {
122 		/*
123 		 * Allow caller not to allocate storage to test if label exists
124 		 */
125 		if (((linfo_cb_arg_t *)arg)->lca_info != NULL)
126 			bcopy(linfo, ((linfo_cb_arg_t *)arg)->lca_info,
127 			    sizeof (ctf_lblinfo_t));
128 		return (1); /* Indicate we found a match */
129 	}
130 
131 	return (0);
132 }
133 
134 /*
135  * Retrieve information about the label with name "lname"
136  */
137 int
138 ctf_label_info(ctf_file_t *fp, const char *lname, ctf_lblinfo_t *linfo)
139 {
140 	linfo_cb_arg_t cb_arg;
141 	int rc;
142 
143 	cb_arg.lca_name = lname;
144 	cb_arg.lca_info = linfo;
145 
146 	if ((rc = ctf_label_iter(fp, label_info_cb, &cb_arg)) == CTF_ERR)
147 		return (rc);
148 
149 	if (rc != 1)
150 		return (ctf_set_errno(fp, ECTF_NOLABEL));
151 
152 	return (0);
153 }
154