aboutsummaryrefslogtreecommitdiff
path: root/libctf/ctf-labels.c
blob: 1755b9720a61382d8830b7129b4b14a33c360021 (plain)
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
/* Labelled ranges of type IDs.
   Copyright (C) 2019 Free Software Foundation, Inc.

   This file is part of libctf.

   libctf is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 3, or (at your option) any later
   version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   See the GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.  If not see
   <http://www.gnu.org/licenses/>.  */

#include <ctf-impl.h>
#include <string.h>

static int
extract_label_info (ctf_file_t *fp, const ctf_lblent_t **ctl,
		    uint32_t *num_labels)
{
  const ctf_header_t *h;

  h = (const ctf_header_t *) fp->ctf_data.cts_data;

  *ctl = (const ctf_lblent_t *) (fp->ctf_buf + h->cth_lbloff);
  *num_labels = (h->cth_objtoff - h->cth_lbloff) / sizeof (ctf_lblent_t);

  return 0;
}

/* Returns the topmost label, or NULL if any errors are encountered.  */

const char *
ctf_label_topmost (ctf_file_t *fp)
{
  const ctf_lblent_t *ctlp = NULL;
  const char *s;
  uint32_t num_labels = 0;

  if (extract_label_info (fp, &ctlp, &num_labels) < 0)
    return NULL;				/* errno is set for us.  */

  if (num_labels == 0)
    {
      (void) ctf_set_errno (fp, ECTF_NOLABELDATA);
      return NULL;
    }

  if ((s = ctf_strraw (fp, (ctlp + num_labels - 1)->ctl_label)) == NULL)
    (void) ctf_set_errno (fp, ECTF_CORRUPT);

  return s;
}

/* Iterate over all labels.  We pass the label string and the lblinfo_t struct
   to the specified callback function.  */
int
ctf_label_iter (ctf_file_t *fp, ctf_label_f *func, void *arg)
{
  const ctf_lblent_t *ctlp = NULL;
  uint32_t i;
  uint32_t num_labels = 0;
  ctf_lblinfo_t linfo;
  const char *lname;
  int rc;

  if (extract_label_info (fp, &ctlp, &num_labels) < 0)
    return -1;			/* errno is set for us.  */

  if (num_labels == 0)
    return (ctf_set_errno (fp, ECTF_NOLABELDATA));

  for (i = 0; i < num_labels; i++, ctlp++)
    {
      if ((lname = ctf_strraw (fp, ctlp->ctl_label)) == NULL)
	{
	  ctf_dprintf ("failed to decode label %u with "
		       "type %u\n", ctlp->ctl_label, ctlp->ctl_type);
	  return (ctf_set_errno (fp, ECTF_CORRUPT));
	}

      linfo.ctb_type = ctlp->ctl_type;
      if ((rc = func (lname, &linfo, arg)) != 0)
	return rc;
    }

  return 0;
}

typedef struct linfo_cb_arg
{
  const char *lca_name;		/* Label we want to retrieve info for.  */
  ctf_lblinfo_t *lca_info;	/* Where to store the info about the label.  */
} linfo_cb_arg_t;

static int
label_info_cb (const char *lname, const ctf_lblinfo_t *linfo, void *arg)
{
  /* If lname matches the label we are looking for, copy the
    lblinfo_t struct for the caller.  */

  if (strcmp (lname, ((linfo_cb_arg_t *) arg)->lca_name) == 0)
    {
      /* * Allow caller not to allocate storage to test if label exists.  */

      if (((linfo_cb_arg_t *) arg)->lca_info != NULL)
	memcpy (((linfo_cb_arg_t *) arg)->lca_info, linfo,
	       sizeof (ctf_lblinfo_t));
      return 1;		/* Indicate we found a match.  */
    }

  return 0;
}

/* Retrieve information about the label with name "lname". */
int
ctf_label_info (ctf_file_t *fp, const char *lname, ctf_lblinfo_t *linfo)
{
  linfo_cb_arg_t cb_arg;
  int rc;

  cb_arg.lca_name = lname;
  cb_arg.lca_info = linfo;

  if ((rc = ctf_label_iter (fp, label_info_cb, &cb_arg)) < 0)
    return rc;

  if (rc != 1)
    return (ctf_set_errno (fp, ECTF_NOLABEL));

  return 0;
}