external/ibm-public/postfix/dist/src/util/percentm.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      percentm 3
   6 /* SUMMARY
   7 /*      expand %m embedded in string to system error text
   8 /* SYNOPSIS
   9 /*      #include <percentm.h>
  10 /*
  11 /*      char    *percentm(const char *src, int err)
  12 /* DESCRIPTION
  13 /*      The percentm() routine makes a copy of the null-terminated string
  14 /*      given via the \fIsrc\fR argument, with %m sequences replaced by
  15 /*      the system error text corresponding to the \fIerr\fR argument.
  16 /*      The result is overwritten upon each successive call.
  17 /*
  18 /*      Arguments:
  19 /* .IP src
  20 /*      A null-terminated input string with zero or more %m sequences.
  21 /* .IP err
  22 /*      A legal \fIerrno\fR value. The text corresponding to this error
  23 /*      value is used when expanding %m sequences.
  24 /* SEE ALSO
  25 /*      syslog(3) system logger library
  26 /* HISTORY
  27 /* .ad
  28 /* .fi
  29 /*      A percentm() routine appears in the TCP Wrapper software
  30 /*      by Wietse Venema.
  31 /* LICENSE
  32 /* .ad
  33 /* .fi
  34 /*      The Secure Mailer license must be distributed with this software.
  35 /* AUTHOR(S)
  36 /*      Wietse Venema
  37 /*      IBM T.J. Watson Research
  38 /*      P.O. Box 704
  39 /*      Yorktown Heights, NY 10598, USA
  40 /*--*/
  41
  42 /* System libraries. */
  43
  44 #include <sys_defs.h>
  45 #include <string.h>
  46
  47 /* Utility library. */
  48
  49 #include "vstring.h"
  50 #include "percentm.h"
  51
  52 /* percentm - replace %m by error message corresponding to value in err */
  53
  54 char   *percentm(const char *str, int err)
  55 {
  56     static VSTRING *vp;
  57     const unsigned char *ip = (const unsigned char *) str;
  58
  59     if (vp == 0)
  60         vp = vstring_alloc(100);                /* grows on demand */
  61     VSTRING_RESET(vp);
  62
  63     while (*ip) {
  64         switch (*ip) {
  65         default:
  66             VSTRING_ADDCH(vp, *ip++);
  67             break;
  68         case '%':
  69             switch (ip[1]) {
  70             default:                            /* leave %<any> alone */
  71                 VSTRING_ADDCH(vp, *ip++);
  72                 /* FALLTHROUGH */
  73             case '\0':                          /* don't fall off end */
  74                 VSTRING_ADDCH(vp, *ip++);
  75                 break;
  76             case 'm':                           /* replace %m */
  77                 vstring_strcat(vp, strerror(err));
  78                 ip += 2;
  79                 break;
  80             }
  81         }
  82     }
  83     VSTRING_TERMINATE(vp);
  84     return (vstring_str(vp));
  85 }
  86