Relocate source files to an src/ subdirectory

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/mount.c

@@ -0,0 +1,110 @@
+/* Mount and unmount helpers
+ *
+ * Copyright (c) 2016  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <string.h>
+#include <mntent.h>
+#include <sys/mount.h>
+
+/*
+ * SysV init on Debian/Ubuntu skips these protected mount points
+ *
+ * It also skips anything below /proc, /sys and /run for good meausre so
+ * we do the same here.  What we want is a list of non-protected tmpfs
+ * and regular filesystems that can be safely unmounted before we do
+ * swapoff, and remount / as read-only, respectively.
+ */
+static int is_protected(char *dir)
+{
+	size_t i;
+	char *protected[] = {
+		"/sys", "/proc",
+		"/.dev", "/dev", "/dev/pts", "/dev/shm", "dev/.static/dev", "/dev/vcs",
+		"/run", "/var/run",
+		"/", NULL
+	};
+	char *any[] = {
+		"/proc/", "/sys/", "/run/", NULL
+	};
+
+	for (i = 0; protected[i]; i++) {
+		if (!strcmp(dir, protected[i]))
+			return 1;
+	}
+
+	for (i = 0; any[i]; i++) {
+		if (!strncmp(dir, any[i], strlen(any[i])))
+			return 1;
+	}
+
+	return 0;
+}
+
+static struct mntent *iterator(char *fstab)
+{
+	static FILE *fp = NULL;
+	static struct mntent *mnt;
+
+	if (!fp && fstab) {
+		fp = setmntent(fstab, "r");
+		if (!fp)
+			return NULL;
+	}
+
+	while ((mnt = getmntent(fp))) {
+		if (is_protected(mnt->mnt_dir))
+			continue;
+
+		return mnt;
+	}
+
+	endmntent(fp);
+	fp = NULL;
+
+	return NULL;
+}
+
+void unmount_tmpfs(void)
+{
+	struct mntent *mnt;
+
+	while ((mnt = iterator("/proc/mounts"))) {
+		if (!strcmp("tmpfs", mnt->mnt_fsname))
+			umount(mnt->mnt_dir);
+	}
+}
+
+void unmount_regular(void)
+{
+	struct mntent *mnt;
+
+	while ((mnt = iterator("/proc/mounts"))) {
+		umount(mnt->mnt_dir);
+	}
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */