+/* Decode OFLAG_STRING, which represents the 2nd argument to `open'.
+ OFLAG_STRING should contain an optional integer, followed by an optional
+ symbolic representation of an open flag using only '|' to separate its
+ components (e.g. "O_WRONLY|O_CREAT|O_TRUNC"). Prefer the symbolic
+ representation if available, falling back on the numeric
+ representation, or to zero if both formats are absent.
+
+ This function should be the inverse of encode_oflag. The numeric
+ representation is not portable from one host to another, but it is
+ for backward compatibility with old-fashioned clients that do not
+ emit symbolic open flags. */
+
+static int
+decode_oflag (char const *oflag_string)
+{
+ char *oflag_num_end;
+ int numeric_oflag = strtol (oflag_string, &oflag_num_end, 10);
+ int symbolic_oflag = 0;
+
+ oflag_string = oflag_num_end;
+ while (ISSPACE ((unsigned char) *oflag_string))
+ oflag_string++;
+
+ do
+ {
+ struct name_value_pair { char const *name; int value; };
+ static struct name_value_pair const table[] =
+ {
+#ifdef O_APPEND
+ {"APPEND", O_APPEND},
+#endif
+ {"CREAT", O_CREAT},
+#ifdef O_DSYNC
+ {"DSYNC", O_DSYNC},
+#endif
+ {"EXCL", O_EXCL},
+#ifdef O_LARGEFILE
+ {"LARGEFILE", O_LARGEFILE}, /* LFS extension for opening large files */
+#endif
+#ifdef O_NOCTTY
+ {"NOCTTY", O_NOCTTY},
+#endif
+#ifdef O_NONBLOCK
+ {"NONBLOCK", O_NONBLOCK},
+#endif
+ {"RDONLY", O_RDONLY},
+ {"RDWR", O_RDWR},
+#ifdef O_RSYNC
+ {"RSYNC", O_RSYNC},
+#endif
+#ifdef O_SYNC
+ {"SYNC", O_SYNC},
+#endif
+ {"TRUNC", O_TRUNC},
+ {"WRONLY", O_WRONLY}
+ };
+ struct name_value_pair const *t;
+ size_t s;
+
+ if (*oflag_string++ != 'O' || *oflag_string++ != '_')
+ return numeric_oflag;
+
+ for (t = table;
+ (strncmp (oflag_string, t->name, s = strlen (t->name)) != 0
+ || (oflag_string[s]
+ && strchr ("ABCDEFGHIJKLMNOPQRSTUVWXYZ_0123456789",
+ oflag_string[s])));
+ t++)
+ if (t == table + sizeof table / sizeof *table - 1)
+ return numeric_oflag;
+
+ symbolic_oflag |= t->value;
+ oflag_string += s;
+ }
+ while (*oflag_string++ == '|');
+
+ return symbolic_oflag;
+}
+
+static struct option const long_opts[] =
+{
+ {"help", no_argument, 0, 'h'},
+ {"version", no_argument, 0, 'v'},
+ {0, 0, 0, 0}
+};
+
+static void
+usage (int status)
+{
+ if (status != EXIT_SUCCESS)
+ fprintf (stderr, _("Try `%s --help' for more information.\n"),
+ program_name);
+ else
+ {
+ printf (_("\
+Usage: %s [OPTION]\n\
+Manipulate a tape drive, accepting commands from a remote process.\n\
+\n\
+ --version Output version info.\n\
+ --help Output this help.\n"),
+ program_name);
+ printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
+ }
+
+ exit (status);
+}