libblkid: const qualifier cleanup

* use "const" in functions where we don't modify arguments

* use "const" when cast from const buffer to any struct (superblock etc.)

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

11 files changed, 55 insertions, 53 deletions

diff --git a/libblkid/src/blkidP.h b/libblkid/src/blkidP.h
index 22c985631..2d272f856 100644
--- a/libblkid/src/blkidP.h
+++ b/libblkid/src/blkidP.h
@@ -484,10 +484,10 @@ extern void *blkid_probe_get_binary_data(blkid_probe pr, struct blkid_chain *chn
 extern struct blkid_prval *blkid_probe_new_val(void)
 			__attribute__((warn_unused_result));
 extern int blkid_probe_set_value(blkid_probe pr, const char *name,
-				unsigned char *data, size_t len)
+				const unsigned char *data, size_t len)
 			__attribute__((nonnull));
 extern int blkid_probe_value_set_data(struct blkid_prval *v,
-				unsigned char *data, size_t len)
+				const unsigned char *data, size_t len)
 			__attribute__((nonnull));
 
 extern int blkid_probe_vsprintf_value(blkid_probe pr, const char *name,
@@ -500,7 +500,7 @@ extern int blkid_probe_sprintf_value(blkid_probe pr, const char *name,
 			__attribute__ ((__format__ (__printf__, 3, 4)));
 
 extern int blkid_probe_set_magic(blkid_probe pr, uint64_t offset,
-				size_t len, unsigned char *magic)
+				size_t len, const unsigned char *magic)
 			__attribute__((nonnull));
 
 extern int blkid_probe_verify_csum(blkid_probe pr, uint64_t csum, uint64_t expected)
diff --git a/libblkid/src/partitions/partitions.c b/libblkid/src/partitions/partitions.c
index f60f3c653..4138904d4 100644
--- a/libblkid/src/partitions/partitions.c
+++ b/libblkid/src/partitions/partitions.c
@@ -557,7 +557,7 @@ static int idinfo_probe(blkid_probe pr, const struct blkid_idinfo *id,
 		}
 		if (rc == BLKID_PROBE_OK && mag && chn && !chn->binary)
 			rc = blkid_probe_set_magic(pr, off, mag->len,
-					(unsigned char *) mag->magic);
+					(const unsigned char *) mag->magic);
 
 		DBG(LOWPROBE, ul_debug("%s: <--- (rc = %d)", id->name, rc));
 	}
@@ -620,7 +620,7 @@ static int partitions_probe(blkid_probe pr, struct blkid_chain *chn)
 			 * functions.
 			 */
 			blkid_probe_set_value(pr, "PTTYPE",
-						(unsigned char *) name,
+						(const unsigned char *) name,
 						strlen(name) + 1);
 
 		DBG(LOWPROBE, ul_debug("<-- leaving probing loop (type=%s) [PARTS idx=%d]",
@@ -755,24 +755,24 @@ static int blkid_partitions_probe_partition(blkid_probe pr)
 			v = blkid_parttable_get_type(tab);
 			if (v)
 				blkid_probe_set_value(pr, "PART_ENTRY_SCHEME",
-					(unsigned char *) v, strlen(v) + 1);
+					(const unsigned char *) v, strlen(v) + 1);
 		}
 
 		v = blkid_partition_get_name(par);
 		if (v)
 			blkid_probe_set_value(pr, "PART_ENTRY_NAME",
-				(unsigned char *) v, strlen(v) + 1);
+				(const unsigned char *) v, strlen(v) + 1);
 
 		v = blkid_partition_get_uuid(par);
 		if (v)
 			blkid_probe_set_value(pr, "PART_ENTRY_UUID",
-				(unsigned char *) v, strlen(v) + 1);
+				(const unsigned char *) v, strlen(v) + 1);
 
 		/* type */
 		v = blkid_partition_get_type_string(par);
 		if (v)
 			blkid_probe_set_value(pr, "PART_ENTRY_TYPE",
-				(unsigned char *) v, strlen(v) + 1);
+				(const unsigned char *) v, strlen(v) + 1);
 		else
 			blkid_probe_sprintf_value(pr, "PART_ENTRY_TYPE",
 				"0x%x", blkid_partition_get_type(par));
diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index 647ae416a..081f8826e 100644
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -1468,7 +1468,7 @@ struct blkid_prval *blkid_probe_assign_value(blkid_probe pr, const char *name)
  * for binary data it's without terminator).
  */
 int blkid_probe_value_set_data(struct blkid_prval *v,
-		unsigned char *data, size_t len)
+		const unsigned char *data, size_t len)
 {
 	v->data = calloc(1, len + 1);	/* always terminate by \0 */
 
@@ -1480,7 +1480,7 @@ int blkid_probe_value_set_data(struct blkid_prval *v,
 }
 
 int blkid_probe_set_value(blkid_probe pr, const char *name,
-		unsigned char *data, size_t len)
+		const unsigned char *data, size_t len)
 {
 	struct blkid_prval *v;
 
@@ -1525,7 +1525,7 @@ int blkid_probe_sprintf_value(blkid_probe pr, const char *name,
 }
 
 int blkid_probe_set_magic(blkid_probe pr, uint64_t offset,
-			size_t len, unsigned char *magic)
+			size_t len, const unsigned char *magic)
 {
 	int rc = 0;
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
diff --git a/libblkid/src/superblocks/bitlocker.c b/libblkid/src/superblocks/bitlocker.c
index 032839d7e..111edf39b 100644
--- a/libblkid/src/superblocks/bitlocker.c
+++ b/libblkid/src/superblocks/bitlocker.c
@@ -82,7 +82,7 @@ static int get_bitlocker_headers(blkid_probe pr,
 {
 
 	const unsigned char *buf;
-	struct bde_fve_metadata *fve;
+	const struct bde_fve_metadata *fve;
 	uint64_t off = 0;
 	int kind;
 
@@ -102,10 +102,10 @@ static int get_bitlocker_headers(blkid_probe pr,
 	/* Check BitLocker header */
 	switch (kind) {
 	case BDE_VERSION_WIN7:
-		off = le64_to_cpu(((struct bde_header_win7 *) buf)->fve_metadata_offset);
+		off = le64_to_cpu(((const struct bde_header_win7 *) buf)->fve_metadata_offset);
 		break;
 	case BDE_VERSION_TOGO:
-		off = le64_to_cpu(((struct bde_header_togo *) buf)->fve_metadata_offset);
+		off = le64_to_cpu(((const struct bde_header_togo *) buf)->fve_metadata_offset);
 		break;
 	case BDE_VERSION_VISTA:
 		goto done;
@@ -123,7 +123,7 @@ static int get_bitlocker_headers(blkid_probe pr,
 	if (!buf)
 		return errno ? -errno : 1;
 
-	fve = (struct bde_fve_metadata *) buf;
+	fve = (const struct bde_fve_metadata *) buf;
 	if (memcmp(fve->signature, BDE_MAGIC_FVE, sizeof(fve->signature)) != 0)
 		goto nothing;
 	if (buf_fve)
@@ -156,17 +156,17 @@ static int probe_bitlocker(blkid_probe pr,
 		return rc;
 
 	if (kind == BDE_VERSION_WIN7) {
-		struct bde_header_win7 *hdr = (struct bde_header_win7 *) buf_hdr;
+		const struct bde_header_win7 *hdr = (const struct bde_header_win7 *) buf_hdr;
 
 		/* Unfortunately, it seems volume_serial is always zero */
 		blkid_probe_sprintf_uuid(pr,
-				(unsigned char *) &hdr->volume_serial,
+				(const unsigned char *) &hdr->volume_serial,
 				sizeof(hdr->volume_serial),
 				"%016d", le32_to_cpu(hdr->volume_serial));
 	}
 
 	if (buf_fve) {
-		struct bde_fve_metadata *fve = (struct bde_fve_metadata *) buf_fve;
+		const struct bde_fve_metadata *fve = (const struct bde_fve_metadata *) buf_fve;
 
 		blkid_probe_sprintf_version(pr, "%d", fve->version);
 	}
diff --git a/libblkid/src/superblocks/minix.c b/libblkid/src/superblocks/minix.c
index c47378d73..d9771ba02 100644
--- a/libblkid/src/superblocks/minix.c
+++ b/libblkid/src/superblocks/minix.c
@@ -18,8 +18,8 @@
 
 static int get_minix_version(const unsigned char *data, int *other_endian)
 {
-	struct minix_super_block *sb = (struct minix_super_block *) data;
-	struct minix3_super_block *sb3 = (struct minix3_super_block *) data;
+	const struct minix_super_block *sb = (const struct minix_super_block *) data;
+	const struct minix3_super_block *sb3 = (const struct minix3_super_block *) data;
 	int version = 0;
 	char *endian;
 
@@ -90,7 +90,7 @@ static int probe_minix(blkid_probe pr,
 	switch (version) {
 	case 1:
 	case 2: {
-		struct minix_super_block *sb = (struct minix_super_block *) data;
+		const struct minix_super_block *sb = (const struct minix_super_block *) data;
 
 		uint16_t state = minix_swab16(swabme, sb->s_state);
 		if ((state & (MINIX_VALID_FS | MINIX_ERROR_FS)) != state)
@@ -106,7 +106,7 @@ static int probe_minix(blkid_probe pr,
 		break;
 	}
 	case 3: {
-		struct minix3_super_block *sb = (struct minix3_super_block *) data;
+		const struct minix3_super_block *sb = (const struct minix3_super_block *) data;
 
 		zones = minix_swab32(swabme, sb->s_zones);
 		ninodes = minix_swab32(swabme, sb->s_ninodes);
diff --git a/libblkid/src/superblocks/stratis.c b/libblkid/src/superblocks/stratis.c
index 96c7df9aa..7fdee2b38 100644
--- a/libblkid/src/superblocks/stratis.c
+++ b/libblkid/src/superblocks/stratis.c
@@ -76,10 +76,10 @@ static int probe_stratis(blkid_probe pr,
 				(buf + SECOND_COPY_OFFSET);
 	}
 
-	blkid_probe_strncpy_uuid(pr, (unsigned char *)stratis->dev_uuid,
+	blkid_probe_strncpy_uuid(pr, stratis->dev_uuid,
 					sizeof(stratis->dev_uuid));
 	blkid_probe_set_value(pr, "POOL_UUID",
-				(unsigned char *)stratis->pool_uuid,
+				stratis->pool_uuid,
 				sizeof(stratis->pool_uuid));
 
 	blkid_probe_sprintf_value(pr, "BLOCKDEV_SECTORS", "%" PRIu64,
diff --git a/libblkid/src/superblocks/superblocks.c b/libblkid/src/superblocks/superblocks.c
index e95c1e626..70d4c2697 100644
--- a/libblkid/src/superblocks/superblocks.c
+++ b/libblkid/src/superblocks/superblocks.c
@@ -417,7 +417,7 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
 		/* all checks passed */
 		if (chn->flags & BLKID_SUBLKS_TYPE)
 			rc = blkid_probe_set_value(pr, "TYPE",
-				(unsigned char *) id->name,
+				(const unsigned char *) id->name,
 				strlen(id->name) + 1);
 
 		if (!rc)
@@ -425,7 +425,7 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
 
 		if (!rc && mag)
 			rc = blkid_probe_set_magic(pr, off, mag->len,
-					(unsigned char *) mag->magic);
+					(const unsigned char *) mag->magic);
 		if (rc) {
 			blkid_probe_chain_reset_values(pr, chn);
 			DBG(LOWPROBE, ul_debug("failed to set result -- ignore"));
@@ -531,7 +531,8 @@ int blkid_probe_set_version(blkid_probe pr, const char *version)
 
 	if (chn->flags & BLKID_SUBLKS_VERSION)
 		return blkid_probe_set_value(pr, "VERSION",
-			   (unsigned char *) version, strlen(version) + 1);
+				(const unsigned char *) version,
+				strlen(version) + 1);
 	return 0;
 }
 
@@ -574,7 +575,7 @@ static int blkid_probe_set_usage(blkid_probe pr, int usage)
 }
 
 int blkid_probe_set_id_label(blkid_probe pr, const char *name,
-			     unsigned char *data, size_t len)
+			     const unsigned char *data, size_t len)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
 	struct blkid_prval *v;
@@ -603,7 +604,7 @@ int blkid_probe_set_id_label(blkid_probe pr, const char *name,
 }
 
 int blkid_probe_set_utf8_id_label(blkid_probe pr, const char *name,
-			     unsigned char *data, size_t len, int enc)
+			     const unsigned char *data, size_t len, int enc)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
 	struct blkid_prval *v;
@@ -633,7 +634,7 @@ int blkid_probe_set_utf8_id_label(blkid_probe pr, const char *name,
 	return rc;
 }
 
-int blkid_probe_set_label(blkid_probe pr, unsigned char *label, size_t len)
+int blkid_probe_set_label(blkid_probe pr, const unsigned char *label, size_t len)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
 	struct blkid_prval *v;
@@ -661,7 +662,7 @@ int blkid_probe_set_label(blkid_probe pr, unsigned char *label, size_t len)
 	return rc;
 }
 
-int blkid_probe_set_utf8label(blkid_probe pr, unsigned char *label,
+int blkid_probe_set_utf8label(blkid_probe pr, const unsigned char *label,
 				size_t len, int enc)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
@@ -693,7 +694,7 @@ int blkid_probe_set_utf8label(blkid_probe pr, unsigned char *label,
 	return rc;
 }
 
-int blkid_probe_sprintf_uuid(blkid_probe pr, unsigned char *uuid,
+int blkid_probe_sprintf_uuid(blkid_probe pr, const unsigned char *uuid,
 				size_t len, const char *fmt, ...)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
@@ -718,7 +719,7 @@ int blkid_probe_sprintf_uuid(blkid_probe pr, unsigned char *uuid,
 }
 
 /* function to set UUIDs that are in superblocks stored as strings */
-int blkid_probe_strncpy_uuid(blkid_probe pr, unsigned char *str, size_t len)
+int blkid_probe_strncpy_uuid(blkid_probe pr, const unsigned char *str, size_t len)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
 	struct blkid_prval *v;
@@ -728,7 +729,7 @@ int blkid_probe_strncpy_uuid(blkid_probe pr, unsigned char *str, size_t len)
 		return -EINVAL;
 
 	if (!len)
-		len = strlen((char *) str);
+		len = strlen((const char *) str);
 
 	if ((chn->flags & BLKID_SUBLKS_UUIDRAW) &&
 	    (rc = blkid_probe_set_value(pr, "UUID_RAW", str, len)) < 0)
@@ -753,7 +754,7 @@ int blkid_probe_strncpy_uuid(blkid_probe pr, unsigned char *str, size_t len)
 }
 
 /* default _set_uuid function to set DCE UUIDs */
-int blkid_probe_set_uuid_as(blkid_probe pr, unsigned char *uuid, const char *name)
+int blkid_probe_set_uuid_as(blkid_probe pr, const unsigned char *uuid, const char *name)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
 	struct blkid_prval *v;
@@ -791,7 +792,7 @@ int blkid_probe_set_uuid_as(blkid_probe pr, unsigned char *uuid, const char *nam
 	return rc;
 }
 
-int blkid_probe_set_uuid(blkid_probe pr, unsigned char *uuid)
+int blkid_probe_set_uuid(blkid_probe pr, const unsigned char *uuid)
 {
 	return blkid_probe_set_uuid_as(pr, uuid, NULL);
 }
diff --git a/libblkid/src/superblocks/superblocks.h b/libblkid/src/superblocks/superblocks.h
index 85858b9fc..11c16e4b4 100644
--- a/libblkid/src/superblocks/superblocks.h
+++ b/libblkid/src/superblocks/superblocks.h
@@ -91,21 +91,21 @@ extern int blkid_probe_set_version(blkid_probe pr, const char *version);
 extern int blkid_probe_sprintf_version(blkid_probe pr, const char *fmt, ...)
 		__attribute__ ((__format__ (__printf__, 2, 3)));
 
-extern int blkid_probe_set_label(blkid_probe pr, unsigned char *label, size_t len);
-extern int blkid_probe_set_utf8label(blkid_probe pr, unsigned char *label,
+extern int blkid_probe_set_label(blkid_probe pr, const unsigned char *label, size_t len);
+extern int blkid_probe_set_utf8label(blkid_probe pr, const unsigned char *label,
                 size_t len, int enc);
-extern int blkid_probe_sprintf_uuid(blkid_probe pr, unsigned char *uuid,
+extern int blkid_probe_sprintf_uuid(blkid_probe pr, const unsigned char *uuid,
                 size_t len, const char *fmt, ...)
 		__attribute__ ((__format__ (__printf__, 4, 5)));
-extern int blkid_probe_strncpy_uuid(blkid_probe pr, unsigned char *str, size_t len);
+extern int blkid_probe_strncpy_uuid(blkid_probe pr, const unsigned char *str, size_t len);
 
-extern int blkid_probe_set_uuid(blkid_probe pr, unsigned char *uuid);
-extern int blkid_probe_set_uuid_as(blkid_probe pr, unsigned char *uuid, const char *name);
+extern int blkid_probe_set_uuid(blkid_probe pr, const unsigned char *uuid);
+extern int blkid_probe_set_uuid_as(blkid_probe pr, const unsigned char *uuid, const char *name);
 
 extern int blkid_probe_set_id_label(blkid_probe pr, const char *name,
-			     unsigned char *data, size_t len);
+			     const unsigned char *data, size_t len);
 extern int blkid_probe_set_utf8_id_label(blkid_probe pr, const char *name,
-			     unsigned char *data, size_t len, int enc);
+			     const unsigned char *data, size_t len, int enc);
 
 extern int blkid_probe_is_bitlocker(blkid_probe pr);
 
diff --git a/libblkid/src/superblocks/vfat.c b/libblkid/src/superblocks/vfat.c
index f4628da4a..5061587ad 100644
--- a/libblkid/src/superblocks/vfat.c
+++ b/libblkid/src/superblocks/vfat.c
@@ -426,10 +426,10 @@ static int probe_vfat(blkid_probe pr, const struct blkid_idmag *mag)
 	}
 
 	if (boot_label && memcmp(boot_label, no_name, 11))
-		blkid_probe_set_id_label(pr, "LABEL_FATBOOT", (unsigned char *) boot_label, 11);
+		blkid_probe_set_id_label(pr, "LABEL_FATBOOT", boot_label, 11);
 
 	if (vol_label)
-		blkid_probe_set_label(pr, (unsigned char *) vol_label, 11);
+		blkid_probe_set_label(pr, vol_label, 11);
 
 	/* We can't just print them as %04X, because they are unaligned */
 	if (vol_serno)
diff --git a/libblkid/src/superblocks/zfs.c b/libblkid/src/superblocks/zfs.c
index ec3e1c5bf..1292b303b 100644
--- a/libblkid/src/superblocks/zfs.c
+++ b/libblkid/src/superblocks/zfs.c
@@ -186,12 +186,12 @@ static void zfs_extract_guid_name(blkid_probe pr, loff_t offset)
 static int find_uberblocks(const void *label, loff_t *ub_offset, int *swap_endian)
 {
 	uint64_t swab_magic = swab64((uint64_t)UBERBLOCK_MAGIC);
-	struct zfs_uberblock *ub;
+	const struct zfs_uberblock *ub;
 	int i, found = 0;
 	loff_t offset = VDEV_LABEL_UBERBLOCK;
 
 	for (i = 0; i < UBERBLOCKS_COUNT; i++, offset += UBERBLOCK_SIZE) {
-		ub = (struct zfs_uberblock *)((char *) label + offset);
+		ub = (const struct zfs_uberblock *)((const char *) label + offset);
 
 		if (ub->ub_magic == UBERBLOCK_MAGIC) {
 			*ub_offset = offset;
diff --git a/libblkid/src/topology/dm.c b/libblkid/src/topology/dm.c
index e061632ca..37fce6d62 100644
--- a/libblkid/src/topology/dm.c
+++ b/libblkid/src/topology/dm.c
@@ -35,7 +35,7 @@ static int probe_dm_tp(blkid_probe pr,
 		"/sbin/dmsetup"
 	};
 	int dmpipe[] = { -1, -1 }, stripes, stripesize;
-	char *cmd = NULL;
+	const char *cmd = NULL;
 	FILE *stream = NULL;
 	long long  offset, size;
 	size_t i;
@@ -49,7 +49,7 @@ static int probe_dm_tp(blkid_probe pr,
 	for (i = 0; i < ARRAY_SIZE(paths); i++) {
 		struct stat sb;
 		if (stat(paths[i], &sb) == 0) {
-			cmd = (char *) paths[i];
+			cmd = paths[i];
 			break;
 		}
 	}
@@ -64,7 +64,8 @@ static int probe_dm_tp(blkid_probe pr,
 	switch (fork()) {
 	case 0:
 	{
-		char *dmargv[7], maj[16], min[16];
+		const char *dmargv[7];
+	        char maj[16], min[16];
 
 		/* Plumbing */
 		close(dmpipe[0]);
@@ -89,7 +90,7 @@ static int probe_dm_tp(blkid_probe pr,
 		dmargv[5] = min;
 		dmargv[6] = NULL;
 
-		execv(dmargv[0], dmargv);
+		execv(dmargv[0], (char * const *) dmargv);
 
 		DBG(LOWPROBE, ul_debug("Failed to execute %s: errno=%d", cmd, errno));
 		exit(1);