lib/libc/gen/getttyent.c

   1 /*      $NetBSD: getttyent.c,v 1.23 2006/04/17 23:29:21 salo Exp $      */
   2
   3 /*
   4  * Copyright (c) 1989, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 #if 0
  35 static char sccsid[] = "@(#)getttyent.c 8.1 (Berkeley) 6/4/93";
  36 #else
  37 __RCSID("$NetBSD: getttyent.c,v 1.23 2006/04/17 23:29:21 salo Exp $");
  38 #endif
  39 #endif /* LIBC_SCCS and not lint */
  40
  41 #include "namespace.h"
  42
  43 #include <assert.h>
  44 #include <ctype.h>
  45 #include <stdio.h>
  46 #include <string.h>
  47 #include <ttyent.h>
  48 #include <errno.h>
  49 #include <err.h>
  50 #include <stdlib.h>
  51
  52 #ifdef __weak_alias
  53 __weak_alias(endttyent,_endttyent)
  54 __weak_alias(getttyent,_getttyent)
  55 __weak_alias(getttynam,_getttynam)
  56 __weak_alias(setttyent,_setttyent)
  57 __weak_alias(setttyentpath,_setttyentpath)
  58 #endif
  59
  60 static FILE *tf;
  61 static size_t lineno = 0;
  62 static char *skip(char *, char *);
  63 static char *value(char *);
  64
  65 struct ttyent *
  66 getttynam(const char *tty)
  67 {
  68         struct ttyent *t;
  69
  70         _DIAGASSERT(tty != NULL);
  71
  72         setttyent();
  73         while ((t = getttyent()) != NULL)
  74                 if (!strcmp(tty, t->ty_name))
  75                         break;
  76         endttyent();
  77         return (t);
  78 }
  79
  80 struct ttyent *
  81 getttyent(void)
  82 {
  83         static struct ttyent tty;
  84         int c;
  85         char *p;
  86         size_t len;
  87         static char *line = NULL;
  88         char zapchar;
  89
  90         if (line)
  91                 free(line);
  92
  93         if (!tf && !setttyent())
  94                 return NULL;
  95
  96         for (;;) {
  97                 errno = 0;
  98                 line = fparseln(tf, &len, &lineno, NULL, FPARSELN_UNESCALL);
  99                 if (line == NULL) {
 100                         if (errno != 0)
 101                                 warn("%s", __func__);
 102                         return NULL;
 103                 }
 104                 for (p = line; *p && isspace((unsigned char)*p); p++)
 105                         continue;
 106                 if (*p && *p != '#')
 107                         break;
 108                 free(line);
 109         }
 110
 111         tty.ty_name = p;
 112         p = skip(p, &zapchar);
 113         if (*(tty.ty_getty = p) == '\0')
 114                 tty.ty_getty = tty.ty_type = NULL;
 115         else {
 116                 p = skip(p, &zapchar);
 117                 if (*(tty.ty_type = p) == '\0')
 118                         tty.ty_type = NULL;
 119                 else
 120                         p = skip(p, &zapchar);
 121         }
 122         tty.ty_status = 0;
 123         tty.ty_window = NULL;
 124         tty.ty_class = NULL;
 125
 126 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && (isspace((unsigned char) p[sizeof(e) - 1]) || p[sizeof(e) - 1] == '\0')
 127 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
 128         for (; *p; p = skip(p, &zapchar)) {
 129                 if (scmp(_TTYS_OFF))
 130                         tty.ty_status &= ~TTY_ON;
 131                 else if (scmp(_TTYS_ON))
 132                         tty.ty_status |= TTY_ON;
 133                 else if (scmp(_TTYS_SECURE))
 134                         tty.ty_status |= TTY_SECURE;
 135                 else if (scmp(_TTYS_LOCAL))
 136                         tty.ty_status |= TTY_LOCAL;
 137                 else if (scmp(_TTYS_RTSCTS))
 138                         tty.ty_status |= TTY_RTSCTS;
 139                 else if (scmp(_TTYS_DTRCTS))
 140                         tty.ty_status |= TTY_DTRCTS;
 141                 else if (scmp(_TTYS_SOFTCAR))
 142                         tty.ty_status |= TTY_SOFTCAR;
 143                 else if (scmp(_TTYS_MDMBUF))
 144                         tty.ty_status |= TTY_MDMBUF;
 145                 else if (vcmp(_TTYS_WINDOW))
 146                         tty.ty_window = value(p);
 147                 else if (vcmp(_TTYS_CLASS))
 148                         tty.ty_class = value(p);
 149                 else
 150                         warnx("%s: %s, %lu: unknown option `%s'",
 151                             __func__, _PATH_TTYS, (unsigned long)lineno, p);
 152         }
 153
 154         if (zapchar == '#' || *p == '#')
 155                 while ((c = *++p) == ' ' || c == '\t')
 156                         continue;
 157         tty.ty_comment = p;
 158         if (*p == '\0')
 159                 tty.ty_comment = NULL;
 160         if ((p = strchr(p, '\n')) != NULL)
 161                 *p = '\0';
 162         return &tty;
 163 }
 164
 165 #define QUOTED  1
 166
 167 /*
 168  * Skip over the current field, removing quotes, and return a pointer to
 169  * the next field.
 170  */
 171 static char *
 172 skip(char *p, char *zapchar)
 173 {
 174         char *t;
 175         int c, q;
 176
 177         _DIAGASSERT(p != NULL);
 178         *zapchar = '\0';
 179
 180         for (q = 0, t = p; (c = *p) != '\0'; p++) {
 181                 if (c == '"') {
 182                         q ^= QUOTED;    /* obscure, but nice */
 183                         continue;
 184                 }
 185                 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
 186                         p++;
 187                 *t++ = *p;
 188                 if (q == QUOTED)
 189                         continue;
 190                 if (c == '#') {
 191                         *zapchar = c;
 192                         *p = '\0';
 193                         *--t = '\0';
 194                         return p;
 195                 }
 196                 if (c == '\t' || c == ' ' || c == '\n') {
 197                         *zapchar = c;
 198                         *p++ = '\0';
 199                         while ((c = *p) == '\t' || c == ' ' || c == '\n')
 200                                 p++;
 201                         *--t = '\0';
 202                         return p;
 203                 }
 204         }
 205         if (t != p)
 206                 *t = '\0';
 207         return p;
 208 }
 209
 210 static char *
 211 value(char *p)
 212 {
 213
 214         _DIAGASSERT(p != NULL);
 215
 216         return (p = strchr(p, '=')) != NULL ? ++p : NULL;
 217 }
 218
 219 int
 220 setttyentpath(const char *path)
 221 {
 222         lineno = 0;
 223         if (tf) {
 224                 rewind(tf);
 225                 return 1;
 226         } else if ((tf = fopen(path, "r")) != NULL)
 227                 return 1;
 228         return 0;
 229 }
 230
 231 int
 232 setttyent(void)
 233 {
 234         return setttyentpath(_PATH_TTYS);
 235 }
 236
 237 int
 238 endttyent(void)
 239 {
 240         int rval;
 241
 242         if (tf) {
 243                 rval = !(fclose(tf) == EOF);
 244                 tf = NULL;
 245                 return rval;
 246         }
 247         return 1;
 248 }