/* Labelled ranges of type IDs.

   Copyright (C) 2019-2025 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_dict_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_dict_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_dict_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)

  {

    /* Not marked for translation: label code not used yet.  */

    ctf_err_warn (fp, 0, ECTF_CORRUPT,

      "failed to decode label %u with type %u",

      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_dict_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;

}