crypto/dist/heimdal/appl/login/read_string.c

   1 /*
   2  * Copyright (c) 1997 - 2000 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "login_locl.h"
  35
  36 __RCSID("$Heimdal: read_string.c 18156 2006-09-22 15:42:39Z lha $"
  37         "$NetBSD$");
  38
  39 static sig_atomic_t intr_flag;
  40
  41 static void
  42 intr(int sig)
  43 {
  44     intr_flag++;
  45 }
  46
  47 #ifndef NSIG
  48 #define NSIG 47
  49 #endif
  50
  51 int
  52 read_string(const char *prompt, char *buf, size_t len, int echo)
  53 {
  54     struct sigaction sigs[NSIG];
  55     int oksigs[NSIG];
  56     struct sigaction sa;
  57     FILE *tty;
  58     int ret = 0;
  59     int of = 0;
  60     int i;
  61     int c;
  62     char *p;
  63
  64     struct termios t_new, t_old;
  65
  66     memset(&oksigs, 0, sizeof(oksigs));
  67
  68     memset(&sa, 0, sizeof(sa));
  69     sa.sa_handler = intr;
  70     sigemptyset(&sa.sa_mask);
  71     sa.sa_flags = 0;
  72     for(i = 1; i < sizeof(sigs) / sizeof(sigs[0]); i++)
  73         if (i != SIGALRM)
  74             if (sigaction(i, &sa, &sigs[i]) == 0)
  75                 oksigs[i] = 1;
  76
  77     if((tty = fopen("/dev/tty", "r")) == NULL)
  78         tty = stdin;
  79
  80     fprintf(stderr, "%s", prompt);
  81     fflush(stderr);
  82
  83     if(echo == 0){
  84         tcgetattr(fileno(tty), &t_old);
  85         memcpy(&t_new, &t_old, sizeof(t_new));
  86         t_new.c_lflag &= ~ECHO;
  87         tcsetattr(fileno(tty), TCSANOW, &t_new);
  88     }
  89     intr_flag = 0;
  90     p = buf;
  91     while(intr_flag == 0){
  92         c = getc(tty);
  93         if(c == EOF){
  94             if(!ferror(tty))
  95                 ret = 1;
  96             break;
  97         }
  98         if(c == '\n')
  99             break;
 100         if(of == 0)
 101             *p++ = c;
 102         of = (p == buf + len);
 103     }
 104     if(of)
 105         p--;
 106     *p = 0;
 107
 108     if(echo == 0){
 109         printf("\n");
 110         tcsetattr(fileno(tty), TCSANOW, &t_old);
 111     }
 112
 113     if(tty != stdin)
 114         fclose(tty);
 115
 116     for(i = 1; i < sizeof(sigs) / sizeof(sigs[0]); i++)
 117         if (oksigs[i])
 118             sigaction(i, &sigs[i], NULL);
 119
 120     if(ret)
 121         return -3;
 122     if(intr_flag)
 123         return -2;
 124     if(of)
 125         return -1;
 126     return 0;
 127 }
 128
 129
 130 #if 0
 131 int main()
 132 {
 133     char s[128];
 134     int ret;
 135     ret = read_string("foo: ", s, sizeof(s), 0);
 136     printf("%d ->%s<-\n", ret, s);
 137 }
 138 #endif