s3: Add extid to the dev/inode pair

This extends the file_id struct to add an additional generic uint64_t
field: extid.  For backwards compatibility with dev/inodes stored in
xattr_tdbs and acl_tdbs, the ext id is ignored for these databases.
This patch should cause no functional change on systems that don't use
SMB_VFS_FILE_ID_CREATE to set the extid.

Existing code that uses the smb_share_mode library will need to be
updated to be compatibile with the new extid.

1 files changed, 24 insertions, 6 deletions

diff --git a/source3/lib/file_id.c b/source3/lib/file_id.c
index 355aafa344..0902e3d224 100644
--- a/source3/lib/file_id.c
+++ b/source3/lib/file_id.c
@@ -34,7 +34,8 @@ struct file_id vfs_file_id_from_sbuf(connection_struct *conn, const SMB_STRUCT_S
  */
 bool file_id_equal(const struct file_id *id1, const struct file_id *id2)
 {
-	return id1->inode == id2->inode && id1->devid == id2->devid;
+	return id1->inode == id2->inode && id1->devid == id2->devid &&
+	    id1->extid == id2->extid;
 }
 
 /*
@@ -42,15 +43,17 @@ bool file_id_equal(const struct file_id *id1, const struct file_id *id2)
  */
 const char *file_id_string_tos(const struct file_id *id)
 {
-	char *result = talloc_asprintf(talloc_tos(), "%llx:%llx", 
+	char *result = talloc_asprintf(talloc_tos(), "%llx:%llx:%llx",
 				       (unsigned long long)id->devid, 
-				       (unsigned long long)id->inode);
+				       (unsigned long long)id->inode,
+				       (unsigned long long)id->extid);
 	SMB_ASSERT(result != NULL);
 	return result;
 }
 
 /*
-  push a 16 byte version of a file id into a buffer
+  push a 16 byte version of a file id into a buffer.  This ignores the extid
+  and is needed when dev/inodes are stored in persistent storage (tdbs).
  */
 void push_file_id_16(char *buf, const struct file_id *id)
 {
@@ -61,13 +64,28 @@ void push_file_id_16(char *buf, const struct file_id *id)
 }
 
 /*
-  pul a 16 byte version of a file id from a buffer
+  push a 24 byte version of a file id into a buffer
  */
-void pull_file_id_16(char *buf, struct file_id *id)
+void push_file_id_24(char *buf, const struct file_id *id)
+{
+	SIVAL(buf,  0, id->devid&0xFFFFFFFF);
+	SIVAL(buf,  4, id->devid>>32);
+	SIVAL(buf,  8, id->inode&0xFFFFFFFF);
+	SIVAL(buf, 12, id->inode>>32);
+	SIVAL(buf, 16, id->extid&0xFFFFFFFF);
+	SIVAL(buf, 20, id->extid>>32);
+}
+
+/*
+  pull a 24 byte version of a file id from a buffer
+ */
+void pull_file_id_24(char *buf, struct file_id *id)
 {
 	ZERO_STRUCTP(id);
 	id->devid  = IVAL(buf,  0);
 	id->devid |= ((uint64_t)IVAL(buf,4))<<32;
 	id->inode  = IVAL(buf,  8);
 	id->inode |= ((uint64_t)IVAL(buf,12))<<32;
+	id->extid  = IVAL(buf,  16);
+	id->extid |= ((uint64_t)IVAL(buf,20))<<32;
 }