// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * mpls functions

 *

 * Copyright (C) 2018 Cumulus Networks, Inc.

 *                    Donald Sharp

 */

#include <zebra.h>

#include <mpls.h>

#include <memory.h>

/*

 * String to label conversion, labels separated by '/'.

 *

 * @param label_str labels separated by /

 * @param num_labels number of labels; zero if conversion was unsuccessful

 * @param labels preallocated mpls_label_t array of size MPLS_MAX_LABELS; only

 *               modified if the conversion succeeded

 * @return  0 on success

 *         -1 if the string could not be parsed as integers

 *         -2 if a label was inside the reserved range (0-15)

 *         -3 if the number of labels given exceeds MPLS_MAX_LABELS

 */

int mpls_str2label(const char *label_str, uint8_t *num_labels,

       mpls_label_t *labels)

{

  char *ostr;       // copy of label string (start)

  char *lstr;       // copy of label string

  char *nump;       // pointer to next segment

  char *endp;       // end pointer

  int i;          // for iterating label_str

  int rc;         // return code

  mpls_label_t pl[MPLS_MAX_LABELS]; // parsed labels

  /* labels to zero until we have a successful parse */

  ostr = lstr = XSTRDUP(MTYPE_TMP, label_str);

  *num_labels = 0;

  rc = 0;

  for (i = 0; i < MPLS_MAX_LABELS && lstr && !rc; i++) {

    nump = strsep(&lstr, "/");

    pl[i] = strtoul(nump, &endp, 10);

    /* format check */

    if (*endp != '\0')

      rc = -1;

    /* validity check */

    else if (!IS_MPLS_UNRESERVED_LABEL(pl[i]))

      rc = -2;

  }

  /* excess labels */

  if (!rc && i == MPLS_MAX_LABELS && lstr)

    rc = -3;

  if (!rc) {

    *num_labels = i;

    memcpy(labels, pl, *num_labels * sizeof(mpls_label_t));

  }

  XFREE(MTYPE_TMP, ostr);

  return rc;

}

/*

 * Label to string conversion, labels in string separated by '/'.

 */

char *mpls_label2str(uint8_t num_labels, const mpls_label_t *labels, char *buf,

         int len, enum lsp_types_t type, int pretty)

{

  char label_buf[BUFSIZ];

  int i;

  buf[0] = '\0';

  for (i = 0; i < num_labels; i++) {

    if (i != 0)

      strlcat(buf, "/", len);

    if (pretty)

      label2str(labels[i], type, label_buf,

          sizeof(label_buf));

    else

      snprintf(label_buf, sizeof(label_buf), "%u",

         ((type == ZEBRA_LSP_EVPN)

            ? label2vni(&labels[i])

            : labels[i]));

    strlcat(buf, label_buf, len);

  }

  return buf;

}