libblkid: add superblocks chain

Signed-off-by: Karel Zak <kzak@redhat.com>

2 files changed, 302 insertions, 0 deletions

diff --git a/shlibs/blkid/src/superblocks/Makefile.am b/shlibs/blkid/src/superblocks/Makefile.am
index 07508702f..16e8d1b56 100644
--- a/shlibs/blkid/src/superblocks/Makefile.am
+++ b/shlibs/blkid/src/superblocks/Makefile.am
@@ -5,6 +5,7 @@ AM_CPPFLAGS += -I$(ul_libblkid_srcdir)
 noinst_LTLIBRARIES = libblkid_superblocks.la
 libblkid_superblocks_la_SOURCES = \
 			superblocks.h \
+			superblocks.c \
 			cramfs.c \
 			swap.c \
 			adaptec_raid.c \
diff --git a/shlibs/blkid/src/superblocks/superblocks.c b/shlibs/blkid/src/superblocks/superblocks.c
new file mode 100644
index 000000000..31c601d4b
--- /dev/null
+++ b/shlibs/blkid/src/superblocks/superblocks.c
@@ -0,0 +1,301 @@
+/*
+ * superblocks.c - reads information from filesystem and raid superblocks
+ *
+ * Copyright (C) 2008-2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdarg.h>
+
+#include "blkdev.h"
+#include "blkidP.h"
+
+#include "superblocks.h"
+
+/**
+ * SECTION:superblocks
+ * @title: Superblocks probing
+ * @short_description: filesystems and raids superblocks probing.
+ *
+ * The library API has been originaly designed for superblocks probing only.
+ * This is reason why some *deprecated* superblock specific functions don't use
+ * '_superblocks_' namespace in the function name. Please, don't use these
+ * functions in new code.
+ *
+ * The 'superblocks' probers support NAME=value (tags) interface only. The
+ * superblocks probing is enabled by default (and controled by
+ * blkid_probe_enable_superblocks()).
+ *
+ * Currently supported tags:
+ *
+ * @TYPE: filesystem type
+ *
+ * @SEC_TYPE: secondary filesystem type
+ *
+ * @LABEL: filesystem label
+ *
+ * @LABEL_RAW: raw label from FS superblock
+ *
+ * @UUID: filesystem UUID (lower case)
+ *
+ * @UUID_RAW: raw UUID from FS superblock
+ *
+ * @EXT_JOURNAL: external journal UUID
+ *
+ * @USAGE:  usage string: "raid", "filesystem", ...
+ *
+ * @VERSION: filesystem version
+ *
+ * @MOUNT: cluster mount name (?) -- ocfs only
+ *
+ * @SBMAGIC: super block magic string [not-implemented yet]
+ *
+ * @SBOFFSET: offset of superblock [not-implemented yet]
+ *
+ * @FSSIZE: size of filessystem [not-implemented yet]
+ */
+
+static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn);
+static int superblocks_safeprobe(blkid_probe pr, struct blkid_chain *chn);
+
+static int blkid_probe_set_usage(blkid_probe pr, int usage);
+
+
+/*
+ * Superblocks chains probing functions
+ */
+static const struct blkid_idinfo *idinfos[] =
+{
+	/* RAIDs */
+	&linuxraid_idinfo,
+	&ddfraid_idinfo,
+	&iswraid_idinfo,
+	&lsiraid_idinfo,
+	&viaraid_idinfo,
+	&silraid_idinfo,
+	&nvraid_idinfo,
+	&pdcraid_idinfo,
+	&highpoint45x_idinfo,
+	&highpoint37x_idinfo,
+	&adraid_idinfo,
+	&jmraid_idinfo,
+	&lvm2_idinfo,
+	&lvm1_idinfo,
+	&snapcow_idinfo,
+	&luks_idinfo,
+
+	/* Filesystems */
+	&vfat_idinfo,
+	&swsuspend_idinfo,
+	&swap_idinfo,
+	&xfs_idinfo,
+	&ext4dev_idinfo,
+	&ext4_idinfo,
+	&ext3_idinfo,
+	&ext2_idinfo,
+	&jbd_idinfo,
+	&reiser_idinfo,
+	&reiser4_idinfo,
+	&jfs_idinfo,
+	&udf_idinfo,
+	&iso9660_idinfo,
+	&zfs_idinfo,
+	&hfsplus_idinfo,
+	&hfs_idinfo,
+	&ufs_idinfo,
+	&hpfs_idinfo,
+	&sysv_idinfo,
+        &xenix_idinfo,
+	&ntfs_idinfo,
+	&cramfs_idinfo,
+	&romfs_idinfo,
+	&minix_idinfo,
+	&gfs_idinfo,
+	&gfs2_idinfo,
+	&ocfs_idinfo,
+	&ocfs2_idinfo,
+	&oracleasm_idinfo,
+	&vxfs_idinfo,
+	&squashfs_idinfo,
+	&netware_idinfo,
+	&btrfs_idinfo
+};
+
+/*
+ * Driver definition
+ */
+const struct blkid_chaindrv superblocks_drv = {
+	.id           = BLKID_CHAIN_SUBLKS,
+	.name         = "superblocks",
+	.dflt_enabled = TRUE,
+	.dflt_flags   = BLKID_SUBLKS_DEFAULT,
+	.idinfos      = idinfos,
+	.nidinfos     = ARRAY_SIZE(idinfos),
+	.has_fltr     = TRUE,
+	.probe        = superblocks_probe,
+	.safeprobe    = superblocks_safeprobe
+};
+
+
+/*
+ * The blkid_do_probe() backend.
+ */
+static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
+{
+	int i = 0;
+
+	if (!pr || chn->idx < -1)
+		return -1;
+	if (chn->idx < -1)
+		return -1;
+	blkid_probe_chain_reset_vals(pr, chn);
+
+	DBG(DEBUG_LOWPROBE,
+		printf("--> starting probing loop [SUBLKS idx=%d]\n",
+		chn->idx));
+
+	i = chn->idx + 1;
+
+	for ( ; i < ARRAY_SIZE(idinfos); i++) {
+		const struct blkid_idinfo *id;
+		const struct blkid_idmag *mag;
+		int hasmag = 0;
+
+		chn->idx = i;
+
+		if (chn->fltr && blkid_bmp_get_item(chn->fltr, i))
+			continue;
+
+		id = idinfos[i];
+		mag = id->magics ? &id->magics[0] : NULL;
+
+		/* try to detect by magic string */
+		while(mag && mag->magic) {
+			blkid_loff_t off;
+			unsigned char *buf;
+
+			off = mag->kboff + ((blkid_loff_t) mag->sboff >> 10);
+			buf = blkid_probe_get_buffer(pr, off << 10, 1024);
+
+			if (buf && !memcmp(mag->magic,
+					buf + (mag->sboff & 0x3ff), mag->len)) {
+				DBG(DEBUG_LOWPROBE, printf(
+					"%s: magic sboff=%u, kboff=%ld\n",
+					id->name, mag->sboff, mag->kboff));
+				hasmag = 1;
+				break;
+			}
+			mag++;
+		}
+
+		if (hasmag == 0 && id->magics && id->magics[0].magic)
+			/* magic string(s) defined, but not found */
+			continue;
+
+		/* final check by probing function */
+		if (id->probefunc) {
+			DBG(DEBUG_LOWPROBE, printf(
+				"%s: call probefunc()\n", id->name));
+			if (id->probefunc(pr, mag) != 0)
+				continue;
+		}
+
+		/* all cheks passed */
+		if (chn->flags & BLKID_SUBLKS_TYPE)
+			blkid_probe_set_value(pr, "TYPE",
+				(unsigned char *) id->name,
+				strlen(id->name) + 1);
+		if (chn->flags & BLKID_SUBLKS_USAGE)
+			blkid_probe_set_usage(pr, id->usage);
+
+		DBG(DEBUG_LOWPROBE,
+			printf("<-- leaving probing loop (type=%s) [SUBLKS idx=%d]\n",
+			id->name, chn->idx));
+		return 0;
+	}
+	DBG(DEBUG_LOWPROBE,
+		printf("<-- leaving probing loop (failed) [SUBLKS idx=%d]\n",
+		chn->idx));
+	return 1;
+}
+
+/*
+ * This is the same function as blkid_do_probe(), but returns only one result
+ * (cannot be used in while()) and checks for ambivalen results (more
+ * filesystems on the device) -- in such case returns -2.
+ *
+ * The function does not check for filesystems when a RAID signature is
+ * detected.  The function also does not check for collision between RAIDs. The
+ * first detected RAID is returned.
+ */
+static int superblocks_safeprobe(blkid_probe pr, struct blkid_chain *chn)
+{
+	struct blkid_prval vals[BLKID_NVALS_SUBLKS];
+	int nvals = BLKID_NVALS_SUBLKS;
+	int idx = -1;
+	int count = 0;
+	int intol = 0;
+	int rc;
+
+	while ((rc = superblocks_probe(pr, chn)) == 0) {
+		if (!count) {
+			/* save the first result */
+			nvals = blkid_probe_chain_copy_vals(pr, chn, vals, nvals);
+			idx = chn->idx;
+		}
+		count++;
+
+		if (idinfos[chn->idx]->usage & BLKID_USAGE_RAID)
+			break;
+		if (!(idinfos[chn->idx]->flags & BLKID_IDINFO_TOLERANT))
+			intol++;
+	}
+	if (rc < 0)
+		return rc;		/* error */
+	if (count > 1 && intol) {
+		DBG(DEBUG_LOWPROBE,
+			printf("ERROR: superblocks chain: "
+			       "ambivalent result detected (%d filesystems)!\n",
+			       count));
+		return -2;		/* error, ambivalent result (more FS) */
+	}
+	if (!count)
+		return 1;		/* nothing detected */
+
+	/* restore the first result */
+	blkid_probe_chain_reset_vals(pr, chn);
+	blkid_probe_append_vals(pr, vals, nvals);
+	chn->idx = idx;
+
+	return 0;
+}
+
+static int blkid_probe_set_usage(blkid_probe pr, int usage)
+{
+	char *u = NULL;
+
+	if (usage & BLKID_USAGE_FILESYSTEM)
+		u = "filesystem";
+	else if (usage & BLKID_USAGE_RAID)
+		u = "raid";
+	else if (usage & BLKID_USAGE_CRYPTO)
+		u = "crypto";
+	else if (usage & BLKID_USAGE_OTHER)
+		u = "other";
+	else
+		u = "unknown";
+
+	return blkid_probe_set_value(pr, "USAGE", (unsigned char *) u, strlen(u) + 1);
+}