external/ibm-public/postfix/dist/src/global/tok822_find.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      tok822_find 3
   6 /* SUMMARY
   7 /*      token list search operators
   8 /* SYNOPSIS
   9 /*      #include <tok822.h>
  10 /*
  11 /*      TOK822  *tok822_find_type(head, type)
  12 /*      TOK822  *head;
  13 /*      int     type;
  14 /*
  15 /*      TOK822  *tok822_rfind_type(tail, type)
  16 /*      TOK822  *tail;
  17 /*      int     type;
  18 /* DESCRIPTION
  19 /*      This module implements token list search operations.
  20 /*
  21 /*      tok822_find_type() searches a list of tokens for the first
  22 /*      instance of the specified token type. The result is the
  23 /*      found token or a null pointer when the search failed.
  24 /*
  25 /*      tok822_rfind_type() searches a list of tokens in reverse direction
  26 /*      for the first instance of the specified token type. The result
  27 /*      is the found token or a null pointer when the search failed.
  28 /* LICENSE
  29 /* .ad
  30 /* .fi
  31 /*      The Secure Mailer license must be distributed with this software.
  32 /* AUTHOR(S)
  33 /*      Wietse Venema
  34 /*      IBM T.J. Watson Research
  35 /*      P.O. Box 704
  36 /*      Yorktown Heights, NY 10598, USA
  37 /*--*/
  38
  39 /* System library. */
  40
  41 #include <sys_defs.h>
  42
  43 /* Utility library. */
  44
  45 #include <vstring.h>
  46
  47 /* Global library. */
  48
  49 #include <tok822.h>
  50
  51 /* tok822_find_type - find specific token type, forward search */
  52
  53 TOK822 *tok822_find_type(TOK822 *head, int op)
  54 {
  55     TOK822 *tp;
  56
  57     for (tp = head; tp != 0 && tp->type != op; tp = tp->next)
  58          /* void */ ;
  59     return (tp);
  60 }
  61
  62 /* tok822_rfind_type - find specific token type, backward search */
  63
  64 TOK822 *tok822_rfind_type(TOK822 *tail, int op)
  65 {
  66     TOK822 *tp;
  67
  68     for (tp = tail; tp != 0 && tp->type != op; tp = tp->prev)
  69          /* void */ ;
  70     return (tp);
  71 }