tests/pwrite_avoid_sigxfsz_28581610.c

   1 /*
   2  * testname: pwrite_avoid_sigxfsz_28581610
   3  */
   4
   5 #include <darwintest.h>
   6 #include <fcntl.h>
   7 #include <limits.h>
   8 #include <setjmp.h>
   9 #include <signal.h>
  10 #include <sys/resource.h>
  11 #include <sys/stat.h>
  12 #include <unistd.h>
  13
  14 T_GLOBAL_META(T_META_RUN_CONCURRENTLY(true));
  15
  16 #define TMP_FILE_PATH "/tmp/test_pwrite_28581610"
  17
  18 static sigjmp_buf xfsz_jmpbuf;
  19
  20 void xfsz_signal(int);
  21
  22 void
  23 xfsz_signal(__unused int signo)
  24 {
  25         siglongjmp(xfsz_jmpbuf, 1);
  26 }
  27
  28 T_DECL(pwrite, "Tests avoiding SIGXFSZ with pwrite and odd offsets",
  29     T_META_ASROOT(true))
  30 {
  31         int fd, x;
  32         off_t ret;
  33         struct stat f_stat;
  34         struct rlimit crl;
  35         static const int offs[] = { -1, -1 * 1024, -1 * 1024 * 16, -1 * 1024 * 1024 * 16, 0 };
  36         static unsigned char buffer[1048576];
  37
  38         T_SETUPBEGIN;
  39         /* We expect zero SIGXFSZ signals because we have no file size limits */
  40         crl.rlim_cur = crl.rlim_max = RLIM_INFINITY;
  41         ret = setrlimit(RLIMIT_FSIZE, &crl);
  42         T_ASSERT_POSIX_SUCCESS(ret, "setting infinite file size limit");
  43
  44         /* we just needed root to setup unlimited file size */
  45         remove(TMP_FILE_PATH);
  46         setuid(5000);
  47
  48         /* We just want an empty regular file to test with */
  49         fd = open(TMP_FILE_PATH, O_RDWR | O_CREAT | O_EXCL, 0777);
  50         T_ASSERT_POSIX_SUCCESS(fd, "opening fd on temp file %s.", TMP_FILE_PATH);
  51
  52         /* sanity check that this new file is really zero bytes in size */
  53         ret = fstat(fd, &f_stat);
  54         T_ASSERT_POSIX_SUCCESS(ret, "stat() fd on temp file.");
  55         T_ASSERT_TRUE(0 == f_stat.st_size, "ensure %s is empty", TMP_FILE_PATH);
  56
  57         /* sanity check that ftruncate() considers negative offsets an error */
  58         for (x = 0; offs[x] != 0; x++) {
  59                 ret = ftruncate(fd, offs[x]);
  60                 T_ASSERT_TRUE(((ret == -1) && (errno == EINVAL)),
  61                     "negative offset %d", offs[x]);
  62         }
  63
  64         T_SETUPEND;
  65
  66         /* we want to get the EFBIG errno but without a SIGXFSZ signal */
  67         if (!sigsetjmp(xfsz_jmpbuf, 1)) {
  68                 signal(SIGXFSZ, xfsz_signal);
  69                 ret = pwrite(fd, buffer, sizeof buffer, QUAD_MAX);
  70                 T_ASSERT_TRUE(((ret == -1) && (errno == EFBIG)),
  71                     "large offset %d", 13);
  72         } else {
  73                 signal(SIGXFSZ, SIG_DFL);
  74                 T_FAIL("%s unexpected SIGXFSZ with offset %lX",
  75                     "<rdar://problem/28581610>", LONG_MAX);
  76         }
  77
  78         /* Negative offsets are invalid, no SIGXFSZ signals required */
  79         for (x = 0; offs[x] != 0; x++) {
  80                 if (!sigsetjmp(xfsz_jmpbuf, 1)) {
  81                         signal(SIGXFSZ, xfsz_signal);
  82                         ret = pwrite(fd, buffer, sizeof buffer, offs[x]);
  83                         T_ASSERT_TRUE(((ret == -1) && (errno == EINVAL)),
  84                             "negative offset %d", offs[x]);
  85                 } else {
  86                         signal(SIGXFSZ, SIG_DFL);
  87                         T_FAIL("%s unexpected SIGXFSZ with negative offset %d",
  88                             "<rdar://problem/28581610>", offs[x]);
  89                 }
  90         }
  91
  92         remove(TMP_FILE_PATH);
  93 }