diplodocus.org Git - nmh/blob - docs/historical/mh-jun-1982/support/aliascheck.c

   1 #ifdef COMMENT
   2         Proprietary Rand Corporation, 1981.
   3         Further distribution of this software
   4         subject to the terms of the Rand
   5         license agreement.
   6 #endif
   7
   8 /*
   9  * aliascheck(name) will return an indication of whether name is
  10  *  a valid alias from AliasFile.  The return values are:
  11  *
  12  *      1 -> yes
  13  *      0 -> no
  14  *     -1 -> an error in the alias file
  15  */
  16
  17 #include <stdio.h>
  18 #include <ctype.h>
  19 char    *AliasFile =    "/etc/MailAliases";
  20
  21 char *
  22 parse(ptr, buf)
  23         register char *ptr;
  24         char *buf;
  25 {
  26         register char *cp = buf;
  27
  28         while(isalnum(*ptr) || *ptr == '/' || *ptr == '-' ||
  29               *ptr == '.' || *ptr == '*')
  30                 *cp++ = *ptr++;
  31         *cp = 0;
  32         if(cp == buf)
  33                 return 0;
  34         return buf;
  35 }
  36
  37
  38 aliascheck(name)
  39         char *name;
  40 {
  41         register char *pp;
  42         char line[256], pbuf[64];
  43         register FILE *a;
  44
  45         if((a = fopen(AliasFile, "r")) == NULL)
  46                 return -1;
  47         while(fgets(line, sizeof line, a)) {
  48                 if(line[0] == ';' || line[0] == '\n')   /* Comment Line */
  49                         continue;
  50                 if((pp = parse(line, pbuf)) == NULL) {
  51                         fclose(a);
  52                         return -1;
  53                 }
  54                 if(aleq(name, pp)) {
  55                         fclose(a);
  56                         return 1;
  57                 }
  58         }
  59         fclose(a);
  60         return 0;
  61 }
  62
  63
  64 aleq(string, aliasent)
  65         register char *string, *aliasent;
  66 {
  67         register int c;
  68
  69         while(c = *string++)
  70                 if(*aliasent == '*')
  71                         return 1;
  72                 else if((c|040) != (*aliasent|040))
  73                         return(0);
  74                 else
  75                         aliasent++;
  76         return *aliasent == 0 || *aliasent == '*';
  77 }