usr/src/common/ctf/ctf_labels.c

   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 }