src/tests/exit-wo-close.c

   1 /*
   2  * Copyright (c) 1995 - 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 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 #endif
  37
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <sys/types.h>
  42 #include <sys/stat.h>
  43 #include <sys/wait.h>
  44 #include <fcntl.h>
  45 #include <unistd.h>
  46
  47 #include <err.h>
  48
  49 static int
  50 child(const char *filename)
  51 {
  52     int fd;
  53     int ret;
  54
  55     fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
  56     if (fd < 0)
  57         err(1, "open %s", filename);
  58     ret = write(fd, "hej", 3);
  59     if (ret != 3)
  60         err(1, "write %s", filename);
  61     return 0;
  62 }
  63
  64 static int
  65 parent(const char *filename, pid_t child_pid)
  66 {
  67     int stat;
  68     int ret;
  69     int fd;
  70     struct stat sb;
  71     char buf[3];
  72
  73     ret = waitpid(child_pid, &stat, 0);
  74     if (ret < 0)
  75         err(1, "waitpid %u", (unsigned)child_pid);
  76     if (!WIFEXITED(stat) || WEXITSTATUS(stat) != 0)
  77         errx(1, "weird child %u", (unsigned)child_pid);
  78     fd = open(filename, O_RDONLY, 0);
  79     if (fd < 0)
  80         err(1, "open %s", filename);
  81     ret = fstat(fd, &sb);
  82     if (ret < 0)
  83         err(1, "fstat %s", filename);
  84     if (sb.st_size != 3)
  85         errx(1, "size of %s = %u != 3", filename, (unsigned)sb.st_size);
  86     ret = read(fd, buf, sizeof(buf));
  87     if (ret < 0)
  88         err(1, "read %s", filename);
  89     if (ret != 3)
  90         errx(1, "short read from %s", filename);
  91     if (memcmp(buf, "hej", 3) != 0)
  92         errx(1, "bad contents of %s = `%.3s'\n", filename, buf);
  93     close(fd);
  94     return 0;
  95 }
  96
  97 static int
  98 doit(const char *filename)
  99 {
 100     pid_t pid;
 101
 102     pid = fork();
 103     if (pid < 0)
 104         err(1, "fork");
 105
 106     if (pid == 0)
 107         return child(filename);
 108     else
 109         return parent(filename, pid);
 110 }
 111
 112 int
 113 main(int argc, char **argv)
 114 {
 115     const char *file = "foo";
 116
 117
 118     if (argc != 2 && argc != 1)
 119         errx(1, "usage: %s [file]", argv[0]);
 120     if (argc == 2)
 121         file = argv[1];
 122     return doit(file);
 123 }