usr/src/lib/extendedFILE/common/extendedFILE.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/types.h>
  30 #include <errno.h>
  31 #include <fcntl.h>
  32 #include <limits.h>
  33 #include <signal.h>
  34 #include <stdio.h>
  35 #include <stdio_ext.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <unistd.h>
  39
  40 #define _FILE_FD_MAX 255
  41
  42 /*
  43  * This 32-bit only preloadable library enables extended fd FILE's.
  44  */
  45
  46 #pragma init(init_STDIO_bad_fd)
  47
  48 void
  49 init_STDIO_bad_fd(void)
  50 {
  51         int action = -1;        /* default signal */
  52         int closed_fd = -1;     /* default fd */
  53         char *ptr;
  54         int signal;
  55         int retval;
  56
  57         /*
  58          * user specified badfd
  59          */
  60         if ((ptr = getenv("_STDIO_BADFD")) != NULL) {
  61                 closed_fd = atoi(ptr);
  62                 if (closed_fd < 3 || closed_fd > _FILE_FD_MAX) {
  63                         (void) fprintf(stderr, "File descriptor must be"
  64                             " in the range 3-%d inclusive.\n", _FILE_FD_MAX);
  65                         exit(1);
  66                 }
  67         }
  68
  69         /*
  70          * user specified action
  71          */
  72         if ((ptr = getenv("_STDIO_BADFD_SIGNAL")) != NULL) {
  73                 /* accept numbers or symbolic names */
  74                 if (strncmp(ptr, "SIG", 3) == 0)        /* begins with "SIG"? */
  75                         ptr = ptr + 3;
  76                 retval = str2sig(ptr, &signal);
  77                 if (retval == -1) {
  78                         (void) fprintf(stderr,
  79                             "Invalid signal name or number.\n");
  80                         exit(1);
  81                 }
  82                 action = signal;
  83         }
  84
  85         if ((closed_fd = enable_extended_FILE_stdio(closed_fd, action)) == -1) {
  86                 perror("enable_extended_FILE_stdio(3C)");
  87                 exit(1);
  88         }
  89 }