1 /* Labelled ranges of type IDs.
2 Copyright (C) 2019-2021 Free Software Foundation, Inc.
3
4 This file is part of libctf.
5
6 libctf is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 This program is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
14 See the GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; see the file COPYING. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #include <ctf-impl.h>
21 #include <string.h>
22
23 static int
extract_label_info(ctf_dict_t * fp,const ctf_lblent_t ** ctl,uint32_t * num_labels)24 extract_label_info (ctf_dict_t *fp, const ctf_lblent_t **ctl,
25 uint32_t *num_labels)
26 {
27 const ctf_header_t *h;
28
29 h = (const ctf_header_t *) fp->ctf_data.cts_data;
30
31 *ctl = (const ctf_lblent_t *) (fp->ctf_buf + h->cth_lbloff);
32 *num_labels = (h->cth_objtoff - h->cth_lbloff) / sizeof (ctf_lblent_t);
33
34 return 0;
35 }
36
37 /* Returns the topmost label, or NULL if any errors are encountered. */
38
39 const char *
ctf_label_topmost(ctf_dict_t * fp)40 ctf_label_topmost (ctf_dict_t *fp)
41 {
42 const ctf_lblent_t *ctlp = NULL;
43 const char *s;
44 uint32_t num_labels = 0;
45
46 if (extract_label_info (fp, &ctlp, &num_labels) < 0)
47 return NULL; /* errno is set for us. */
48
49 if (num_labels == 0)
50 {
51 (void) ctf_set_errno (fp, ECTF_NOLABELDATA);
52 return NULL;
53 }
54
55 if ((s = ctf_strraw (fp, (ctlp + num_labels - 1)->ctl_label)) == NULL)
56 (void) ctf_set_errno (fp, ECTF_CORRUPT);
57
58 return s;
59 }
60
61 /* Iterate over all labels. We pass the label string and the lblinfo_t struct
62 to the specified callback function. */
63 int
ctf_label_iter(ctf_dict_t * fp,ctf_label_f * func,void * arg)64 ctf_label_iter (ctf_dict_t *fp, ctf_label_f *func, void *arg)
65 {
66 const ctf_lblent_t *ctlp = NULL;
67 uint32_t i;
68 uint32_t num_labels = 0;
69 ctf_lblinfo_t linfo;
70 const char *lname;
71 int rc;
72
73 if (extract_label_info (fp, &ctlp, &num_labels) < 0)
74 return -1; /* errno is set for us. */
75
76 if (num_labels == 0)
77 return (ctf_set_errno (fp, ECTF_NOLABELDATA));
78
79 for (i = 0; i < num_labels; i++, ctlp++)
80 {
81 if ((lname = ctf_strraw (fp, ctlp->ctl_label)) == NULL)
82 {
83 /* Not marked for translation: label code not used yet. */
84 ctf_err_warn (fp, 0, ECTF_CORRUPT,
85 "failed to decode label %u with type %u",
86 ctlp->ctl_label, ctlp->ctl_type);
87 return (ctf_set_errno (fp, ECTF_CORRUPT));
88 }
89
90 linfo.ctb_type = ctlp->ctl_type;
91 if ((rc = func (lname, &linfo, arg)) != 0)
92 return rc;
93 }
94
95 return 0;
96 }
97
98 typedef struct linfo_cb_arg
99 {
100 const char *lca_name; /* Label we want to retrieve info for. */
101 ctf_lblinfo_t *lca_info; /* Where to store the info about the label. */
102 } linfo_cb_arg_t;
103
104 static int
label_info_cb(const char * lname,const ctf_lblinfo_t * linfo,void * arg)105 label_info_cb (const char *lname, const ctf_lblinfo_t *linfo, void *arg)
106 {
107 /* If lname matches the label we are looking for, copy the
108 lblinfo_t struct for the caller. */
109
110 if (strcmp (lname, ((linfo_cb_arg_t *) arg)->lca_name) == 0)
111 {
112 /* * Allow caller not to allocate storage to test if label exists. */
113
114 if (((linfo_cb_arg_t *) arg)->lca_info != NULL)
115 memcpy (((linfo_cb_arg_t *) arg)->lca_info, linfo,
116 sizeof (ctf_lblinfo_t));
117 return 1; /* Indicate we found a match. */
118 }
119
120 return 0;
121 }
122
123 /* Retrieve information about the label with name "lname". */
124 int
ctf_label_info(ctf_dict_t * fp,const char * lname,ctf_lblinfo_t * linfo)125 ctf_label_info (ctf_dict_t *fp, const char *lname, ctf_lblinfo_t *linfo)
126 {
127 linfo_cb_arg_t cb_arg;
128 int rc;
129
130 cb_arg.lca_name = lname;
131 cb_arg.lca_info = linfo;
132
133 if ((rc = ctf_label_iter (fp, label_info_cb, &cb_arg)) < 0)
134 return rc;
135
136 if (rc != 1)
137 return (ctf_set_errno (fp, ECTF_NOLABEL));
138
139 return 0;
140 }
141