gen/getttyent.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * Copyright (c) 1989, 1993
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * Redistribution and use in source and binary forms, with or without
  28  * modification, are permitted provided that the following conditions
  29  * are met:
  30  * 1. Redistributions of source code must retain the above copyright
  31  *    notice, this list of conditions and the following disclaimer.
  32  * 2. Redistributions in binary form must reproduce the above copyright
  33  *    notice, this list of conditions and the following disclaimer in the
  34  *    documentation and/or other materials provided with the distribution.
  35  * 3. All advertising materials mentioning features or use of this software
  36  *    must display the following acknowledgement:
  37  *      This product includes software developed by the University of
  38  *      California, Berkeley and its contributors.
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  */
  55
  56
  57 #include <ttyent.h>
  58 #include <stdio.h>
  59 #include <ctype.h>
  60 #include <string.h>
  61 #include <stdlib.h>
  62
  63 static char zapchar;
  64 static FILE *tf;
  65
  66 struct ttyent *
  67 getttynam(tty)
  68         const char *tty;
  69 {
  70         register struct ttyent *t;
  71
  72         setttyent();
  73         while (t = getttyent())
  74                 if (!strcmp(tty, t->ty_name))
  75                         break;
  76         endttyent();
  77         return (t);
  78 }
  79
  80 struct ttyent *
  81 getttyent()
  82 {
  83         static struct ttyent tty;
  84         register int c;
  85         register char *p;
  86 #define MAXLINELENGTH   1024
  87         static char *line = NULL;
  88         static char *skip(), *value();
  89
  90         if ( line == NULL ) {
  91                 line = malloc(MAXLINELENGTH);
  92                 if( line == NULL )
  93                         return NULL;
  94         }
  95
  96         if (!tf && !setttyent())
  97                 return (NULL);
  98         for (;;) {
  99                 if (!fgets(p = line, MAXLINELENGTH, tf))
 100                         return (NULL);
 101                 /* skip lines that are too big */
 102                 if (!index(p, '\n')) {
 103                         while ((c = getc(tf)) != '\n' && c != EOF)
 104                                 ;
 105                         continue;
 106                 }
 107                 while (isspace(*p))
 108                         ++p;
 109                 if (*p && *p != '#')
 110                         break;
 111         }
 112
 113         zapchar = 0;
 114         tty.ty_name = p;
 115         p = skip(p);
 116         if (!*(tty.ty_getty = p))
 117                 tty.ty_getty = tty.ty_type = NULL;
 118         else {
 119                 p = skip(p);
 120                 if (!*(tty.ty_type = p))
 121                         tty.ty_type = NULL;
 122                 else
 123                         p = skip(p);
 124         }
 125         tty.ty_status = 0;
 126         tty.ty_window = NULL;
 127         tty.ty_onerror = NULL;
 128         tty.ty_onoption = NULL;
 129
 130 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace(p[sizeof(e) - 1])
 131 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
 132         for (; *p; p = skip(p)) {
 133                 if (scmp(_TTYS_OFF))
 134                         tty.ty_status &= ~TTY_ON;
 135                 else if (scmp(_TTYS_ON))
 136                         tty.ty_status |= TTY_ON;
 137                 else if (scmp(_TTYS_SECURE))
 138                         tty.ty_status |= TTY_SECURE;
 139                 else if (vcmp(_TTYS_WINDOW))
 140                         tty.ty_window = value(p);
 141                 else if (vcmp(_TTYS_ONERROR))
 142                         tty.ty_onerror = value(p);
 143                 else if (vcmp(_TTYS_ONOPTION))
 144                         tty.ty_onoption = value(p);
 145                 else
 146                         break;
 147         }
 148
 149         if (zapchar == '#' || *p == '#')
 150                 while ((c = *++p) == ' ' || c == '\t')
 151                         ;
 152         tty.ty_comment = p;
 153         if (*p == 0)
 154                 tty.ty_comment = 0;
 155         if (p = index(p, '\n'))
 156                 *p = '\0';
 157         return (&tty);
 158 }
 159
 160 #define QUOTED  1
 161
 162 /*
 163  * Skip over the current field, removing quotes, and return a pointer to
 164  * the next field.
 165  */
 166 static char *
 167 skip(p)
 168         register char *p;
 169 {
 170         register char *t;
 171         register int c, q;
 172
 173         for (q = 0, t = p; (c = *p) != '\0'; p++) {
 174                 if (c == '"') {
 175                         q ^= QUOTED;    /* obscure, but nice */
 176                         continue;
 177                 }
 178                 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
 179                         p++;
 180                 *t++ = *p;
 181                 if (q == QUOTED)
 182                         continue;
 183                 if (c == '#') {
 184                         zapchar = c;
 185                         *p = 0;
 186                         break;
 187                 }
 188                 if (c == '\t' || c == ' ' || c == '\n') {
 189                         zapchar = c;
 190                         *p++ = 0;
 191                         while ((c = *p) == '\t' || c == ' ' || c == '\n')
 192                                 p++;
 193                         break;
 194                 }
 195         }
 196         *--t = '\0';
 197         return (p);
 198 }
 199
 200 static char *
 201 value(p)
 202         register char *p;
 203 {
 204
 205         return ((p = index(p, '=')) ? ++p : NULL);
 206 }
 207
 208 int
 209 setttyent()
 210 {
 211
 212         if (tf) {
 213                 (void)rewind(tf);
 214                 return (1);
 215         } else if (tf = fopen(_PATH_TTYS, "r"))
 216                 return (1);
 217         return (0);
 218 }
 219
 220 int
 221 endttyent()
 222 {
 223         int rval;
 224
 225         if (tf) {
 226                 rval = !(fclose(tf) == EOF);
 227                 tf = NULL;
 228                 return (rval);
 229         }
 230         return (1);
 231 }