4.3BSD - /usr/src/lib/libc/gen/getttyent.c

   1: /*
   2:  * Copyright (c) 1985 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #if defined(LIBC_SCCS) && !defined(lint)
   8: static char sccsid[] = "@(#)getttyent.c	5.4 (Berkeley) 5/19/86";
   9: #endif LIBC_SCCS and not lint
  10: 
  11: #include <stdio.h>
  12: #include <strings.h>
  13: #include <ttyent.h>
  14: 
  15: static char TTYFILE[] = "/etc/ttys";
  16: static char zapchar;
  17: static FILE *tf = NULL;
  18: #define LINE 256
  19: static char line[LINE];
  20: static struct ttyent tty;
  21: 
  22: setttyent()
  23: {
  24:     if (tf == NULL)
  25:         tf = fopen(TTYFILE, "r");
  26:     else
  27:         rewind(tf);
  28: }
  29: 
  30: endttyent()
  31: {
  32:     if (tf != NULL) {
  33:         (void) fclose(tf);
  34:         tf = NULL;
  35:     }
  36: }
  37: 
  38: #define QUOTED  1
  39: 
  40: /*
  41:  * Skip over the current field, removing quotes,
  42:  * and return a pointer to the next field.
  43:  */
  44: static char *
  45: skip(p)
  46:     register char *p;
  47: {
  48:     register char *t = p;
  49:     register int c;
  50:     register int q = 0;
  51: 
  52:     for (; (c = *p) != '\0'; p++) {
  53:         if (c == '"') {
  54:             q ^= QUOTED;    /* obscure, but nice */
  55:             continue;
  56:         }
  57:         if (q == QUOTED && *p == '\\' && *(p+1) == '"')
  58:             p++;
  59:         *t++ = *p;
  60:         if (q == QUOTED)
  61:             continue;
  62:         if (c == '#') {
  63:             zapchar = c;
  64:             *p = 0;
  65:             break;
  66:         }
  67:         if (c == '\t' || c == ' ' || c == '\n') {
  68:             zapchar = c;
  69:             *p++ = 0;
  70:             while ((c = *p) == '\t' || c == ' ' || c == '\n')
  71:                 p++;
  72:             break;
  73:         }
  74:     }
  75:     *--t = '\0';
  76:     return (p);
  77: }
  78: 
  79: static char *
  80: value(p)
  81:     register char *p;
  82: {
  83:     if ((p = index(p,'=')) == 0)
  84:         return(NULL);
  85:     p++;            /* get past the = sign */
  86:     return(p);
  87: }
  88: 
  89: struct ttyent *
  90: getttyent()
  91: {
  92:     register char *p;
  93:     register int c;
  94: 
  95:     if (tf == NULL) {
  96:         if ((tf = fopen(TTYFILE, "r")) == NULL)
  97:             return (NULL);
  98:     }
  99:     do {
 100:         p = fgets(line, LINE, tf);
 101:         if (p == NULL)
 102:             return (NULL);
 103:         while ((c = *p) == '\t' || c == ' ' || c == '\n')
 104:             p++;
 105:     } while (c == '\0' || c == '#');
 106:     zapchar = 0;
 107:     tty.ty_name = p;
 108:     p = skip(p);
 109:     tty.ty_getty = p;
 110:     p = skip(p);
 111:     tty.ty_type = p;
 112:     p = skip(p);
 113:     tty.ty_status = 0;
 114:     tty.ty_window = NULL;
 115:     for (; *p; p = skip(p)) {
 116: #define space(x) ((c = p[x]) == ' ' || c == '\t' || c == '\n')
 117:         if (strncmp(p, "on", 2) == 0 && space(2))
 118:             tty.ty_status |= TTY_ON;
 119:         else if (strncmp(p, "off", 3) == 0 && space(3))
 120:             tty.ty_status &= ~TTY_ON;
 121:         else if (strncmp(p, "secure", 6) == 0 && space(6))
 122:             tty.ty_status |= TTY_SECURE;
 123:         else if (strncmp(p, "window=", 7) == 0)
 124:             tty.ty_window = value(p);
 125:         else
 126:             break;
 127:     }
 128:     if (zapchar == '#' || *p == '#')
 129:         while ((c = *++p) == ' ' || c == '\t')
 130:             ;
 131:     tty.ty_comment = p;
 132:     if (*p == 0)
 133:         tty.ty_comment = 0;
 134:     if (p = index(p, '\n'))
 135:         *p = '\0';
 136:     return(&tty);
 137: }

Defined functions

Defined variables

Defined macros