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-rw-r--r--libbb/find_root_device.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/libbb/find_root_device.c b/libbb/find_root_device.c
new file mode 100644
index 0000000..de765ce
--- /dev/null
+++ b/libbb/find_root_device.c
@@ -0,0 +1,85 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) tons of folks. Tracking down who wrote what
+ * isn't something I'm going to worry about... If you wrote something
+ * here, please feel free to acknowledge your work.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Based in part on code from sash, Copyright (c) 1999 by David I. Bell
+ * Permission has been granted to redistribute this code under the GPL.
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <dirent.h>
+#include "libbb.h"
+
+
+
+extern int find_real_root_device_name(char* name)
+{
+ DIR *dir;
+ struct dirent *entry;
+ struct stat statBuf, rootStat;
+ char fileName[BUFSIZ];
+
+ if (stat("/", &rootStat) != 0) {
+ error_msg("could not stat '/'");
+ return( FALSE);
+ }
+
+ dir = opendir("/dev");
+ if (!dir) {
+ error_msg("could not open '/dev'");
+ return( FALSE);
+ }
+
+ while((entry = readdir(dir)) != NULL) {
+
+ /* Must skip ".." since that is "/", and so we
+ * would get a false positive on ".." */
+ if (strcmp(entry->d_name, "..") == 0)
+ continue;
+
+ snprintf( fileName, strlen(name)+1, "/dev/%s", entry->d_name);
+
+ if (stat(fileName, &statBuf) != 0)
+ continue;
+ /* Some char devices have the same dev_t as block
+ * devices, so make sure this is a block device */
+ if (! S_ISBLK(statBuf.st_mode))
+ continue;
+ if (statBuf.st_rdev == rootStat.st_rdev) {
+ strcpy(name, fileName);
+ return ( TRUE);
+ }
+ }
+
+ return( FALSE);
+}
+
+
+/* END CODE */
+/*
+Local Variables:
+c-file-style: "linux"
+c-basic-offset: 4
+tab-width: 4
+End:
+*/