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-rw-r--r--lib/libc/gen/devname.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/lib/libc/gen/devname.c b/lib/libc/gen/devname.c
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+/*
+ * Copyright (c) 1989, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)devname.c 8.2 (Berkeley) 4/29/95";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+#include <db.h>
+#include <err.h>
+#include <fcntl.h>
+#include <paths.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+
+static char *
+xdevname(dev, type)
+ dev_t dev;
+ mode_t type;
+{
+ struct {
+ mode_t type;
+ dev_t dev;
+ } bkey;
+ static DB *db;
+ static int failure;
+ DBT data, key;
+
+ if (!db && !failure &&
+ !(db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL)))
+ failure = 1;
+ if (failure)
+ return (NULL);
+
+ /*
+ * Keys are a mode_t followed by a dev_t. The former is the type of
+ * the file (mode & S_IFMT), the latter is the st_rdev field. Be
+ * sure to clear any padding that may be found in bkey.
+ */
+ memset(&bkey, 0, sizeof(bkey));
+ bkey.dev = dev;
+ bkey.type = type;
+ key.data = &bkey;
+ key.size = sizeof(bkey);
+ return ((db->get)(db, &key, &data, 0) ? NULL : (char *)data.data);
+}
+
+char *
+devname(dev, type)
+ dev_t dev;
+ mode_t type;
+{
+ static char buf[SPECNAMELEN + 1];
+ int i;
+ size_t j;
+ char *r;
+
+ /* First check the DB file. */
+ r = xdevname(dev, type);
+ if (r != NULL)
+ return (r);
+
+ /* Then ask the kernel. */
+ if ((type & S_IFMT) == S_IFCHR) {
+ j = sizeof(buf);
+ i = sysctlbyname("kern.devname", buf, &j, &dev, sizeof (dev));
+ if (i == 0)
+ return (buf);
+ }
+
+ /* Finally just format it */
+ if (minor(dev) > 255)
+ r = "#%c:%d:0x%x";
+ else
+ r = "#%c:%d:0x%d";
+ snprintf(buf, SPECNAMELEN + 1, r,
+ (type & S_IFMT) == S_IFCHR ? 'C' : 'B', major(dev), minor(dev));
+ return (buf);
+}
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