r3798: added support for alternate data streams in xattrs into pvfs.

The trickiest part about this was getting the sharing and locking
rules right, as alternate streams are separate locking spaces from the
main file for the purposes of byte range locking, and separate for
most share violation rules.

I suspect there are still problems with delete on close with alternate
data streams. I'll look at that next.
(This used to be commit b6452c4a2068cf7e837778559da002ae191b508a)

1 files changed, 322 insertions, 0 deletions

diff --git a/source4/ntvfs/posix/pvfs_streams.c b/source4/ntvfs/posix/pvfs_streams.c
index b71ff640e5..7edf111fc9 100644
--- a/source4/ntvfs/posix/pvfs_streams.c
+++ b/source4/ntvfs/posix/pvfs_streams.c
@@ -25,3 +25,325 @@
 #include "vfs_posix.h"
 #include "librpc/gen_ndr/ndr_xattr.h"
 
+
+/*
+  return the list of file streams for RAW_FILEINFO_STREAM_INFORMATION
+*/
+NTSTATUS pvfs_stream_information(struct pvfs_state *pvfs, 
+				 TALLOC_CTX *mem_ctx,
+				 struct pvfs_filename *name, int fd, 
+				 struct stream_information *info)
+{
+	struct xattr_DosStreams *streams;
+	int i;
+	NTSTATUS status;
+
+	streams = talloc_p(mem_ctx, struct xattr_DosStreams);
+	if (streams == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = pvfs_streams_load(pvfs, name, fd, streams);
+	if (!NT_STATUS_IS_OK(status)) {
+		ZERO_STRUCTP(streams);
+	}
+
+	info->num_streams = streams->num_streams+1;
+	info->streams = talloc_array_p(mem_ctx, struct stream_struct, info->num_streams);
+	if (!info->streams) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	info->streams[0].size          = name->st.st_size;
+	info->streams[0].alloc_size    = name->dos.alloc_size;
+	info->streams[0].stream_name.s = talloc_strdup(info->streams, "::$DATA");
+
+	for (i=0;i<streams->num_streams;i++) {
+		info->streams[i+1].size          = streams->streams[i].size;
+		info->streams[i+1].alloc_size    = streams->streams[i].alloc_size;
+		info->streams[i+1].stream_name.s = talloc_asprintf(streams->streams, 
+								   ":%s:$DATA",
+								   streams->streams[i].name);
+	}
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  fill in the stream information for a name
+*/
+NTSTATUS pvfs_stream_info(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd)
+{
+	struct xattr_DosStreams *streams;
+	int i;
+	NTSTATUS status;
+
+	/* the NULL stream always exists */
+	if (name->stream_name == NULL) {
+		name->stream_exists = True;
+		return NT_STATUS_OK;
+	}
+
+	streams = talloc_p(name, struct xattr_DosStreams);
+	if (streams == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = pvfs_streams_load(pvfs, name, fd, streams);
+	if (!NT_STATUS_IS_OK(status)) {
+		talloc_free(streams);
+		return status;
+	}
+
+	for (i=0;i<streams->num_streams;i++) {
+		struct xattr_DosStream *s = &streams->streams[i];
+		if (StrCaseCmp(s->name, name->stream_name) == 0) {
+			name->dos.alloc_size = s->alloc_size;
+			name->st.st_size     = s->size;
+			name->stream_exists = True;
+			talloc_free(streams);
+			return NT_STATUS_OK;
+		}
+	}
+
+	talloc_free(streams);
+
+	name->dos.alloc_size = 0;
+	name->st.st_size     = 0;
+	name->stream_exists = False;
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  update size information for a stream
+*/
+static NTSTATUS pvfs_stream_update_size(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd,
+					off_t size)
+{
+	struct xattr_DosStreams *streams;
+	int i;
+	NTSTATUS status;
+
+	streams = talloc_p(name, struct xattr_DosStreams);
+	if (streams == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = pvfs_streams_load(pvfs, name, fd, streams);
+	if (!NT_STATUS_IS_OK(status)) {
+		ZERO_STRUCTP(streams);
+	}
+
+	for (i=0;i<streams->num_streams;i++) {
+		struct xattr_DosStream *s = &streams->streams[i];
+		if (StrCaseCmp(s->name, name->stream_name) == 0) {
+			s->size       = size;
+			s->alloc_size = size;
+			break;
+		}
+	}
+
+	if (i == streams->num_streams) {
+		struct xattr_DosStream *s;
+		streams->streams = talloc_realloc_p(streams, streams->streams, 
+						    struct xattr_DosStream,
+						    streams->num_streams+1);
+		if (streams->streams == NULL) {
+			talloc_free(streams);
+			return NT_STATUS_NO_MEMORY;
+		}
+		streams->num_streams++;
+		s = &streams->streams[i];
+		
+		s->flags      = XATTR_STREAM_FLAG_INTERNAL;
+		s->size       = size;
+		s->alloc_size = size;
+		s->name       = name->stream_name;
+	}
+
+	status = pvfs_streams_save(pvfs, name, fd, streams);
+	talloc_free(streams);
+
+	return status;
+}
+
+
+/*
+  create the xattr for a alternate data stream
+*/
+NTSTATUS pvfs_stream_create(struct pvfs_state *pvfs, 
+			    struct pvfs_filename *name, 
+			    int fd)
+{
+	NTSTATUS status;
+	status = pvfs_xattr_create(pvfs, name->full_name, fd, 
+				   XATTR_DOSSTREAM_PREFIX, name->stream_name);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	return pvfs_stream_update_size(pvfs, name, fd, 0);
+}
+
+/*
+  delete the xattr for a alternate data stream
+*/
+NTSTATUS pvfs_stream_delete(struct pvfs_state *pvfs, 
+			    struct pvfs_filename *name, 
+			    int fd)
+{
+	NTSTATUS status;
+	struct xattr_DosStreams *streams;
+	int i;
+
+	status = pvfs_xattr_delete(pvfs, name->full_name, fd, 
+				   XATTR_DOSSTREAM_PREFIX, name->stream_name);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	streams = talloc_p(name, struct xattr_DosStreams);
+	if (streams == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	status = pvfs_streams_load(pvfs, name, fd, streams);
+	if (!NT_STATUS_IS_OK(status)) {
+		talloc_free(streams);
+		return status;
+	}
+
+	for (i=0;i<streams->num_streams;i++) {
+		struct xattr_DosStream *s = &streams->streams[i];
+		if (StrCaseCmp(s->name, name->stream_name) == 0) {
+			memmove(s, s+1, (streams->num_streams - (i+1)) * sizeof(*s));
+			streams->num_streams--;
+			break;
+		}
+	}
+
+	status = pvfs_streams_save(pvfs, name, fd, streams);
+	talloc_free(streams);
+
+	return status;
+}
+
+/*
+  the equvalent of pread() on a stream
+*/
+ssize_t pvfs_stream_read(struct pvfs_state *pvfs,
+			 struct pvfs_file_handle *h, void *data, size_t count, off_t offset)
+{
+	NTSTATUS status;
+	DATA_BLOB blob;
+	if (count == 0) {
+		return 0;
+	}
+	status = pvfs_xattr_load(pvfs, h, h->name->full_name, h->fd, XATTR_DOSSTREAM_PREFIX,
+				 h->name->stream_name, offset+count, &blob);
+	if (!NT_STATUS_IS_OK(status)) {
+		errno = EIO;
+		return -1;
+	}
+	if (offset >= blob.length) {
+		data_blob_free(&blob);
+		return 0;
+	}
+	if (count > blob.length - offset) {
+		count = blob.length - offset;
+	}
+	memcpy(data, blob.data + offset, count);
+	data_blob_free(&blob);
+	return count;
+}
+
+
+/*
+  the equvalent of pwrite() on a stream
+*/
+ssize_t pvfs_stream_write(struct pvfs_state *pvfs,
+			  struct pvfs_file_handle *h, const void *data, size_t count, off_t offset)
+{
+	NTSTATUS status;
+	DATA_BLOB blob;
+	if (count == 0) {
+		return 0;
+	}
+	/* we have to load the existing stream, then modify, then save */
+	status = pvfs_xattr_load(pvfs, h, h->name->full_name, h->fd, XATTR_DOSSTREAM_PREFIX,
+				 h->name->stream_name, offset+count, &blob);
+	if (!NT_STATUS_IS_OK(status)) {
+		blob = data_blob(NULL, 0);
+	}
+	if (count+offset > blob.length) {
+		blob.data = talloc_realloc(blob.data, blob.data, count+offset);
+		if (blob.data == NULL) {
+			errno = ENOMEM;
+			return -1;
+		}
+		if (offset > blob.length) {
+			memset(blob.data+blob.length, 0, offset - blob.length);
+		}
+		blob.length = count+offset;
+	}
+	memcpy(blob.data + offset, data, count);
+
+	status = pvfs_xattr_save(pvfs, h->name->full_name, h->fd, XATTR_DOSSTREAM_PREFIX,
+				 h->name->stream_name, &blob);
+	if (!NT_STATUS_IS_OK(status)) {
+		data_blob_free(&blob);
+		/* getting this error mapping right is probably
+		   not worth it */
+		errno = ENOSPC;
+		return -1;
+	}
+
+	status = pvfs_stream_update_size(pvfs, h->name, h->fd, blob.length);
+
+	data_blob_free(&blob);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		errno = EIO;
+		return -1;
+	}
+
+	return count;
+}
+
+/*
+  the equvalent of truncate() on a stream
+*/
+NTSTATUS pvfs_stream_truncate(struct pvfs_state *pvfs,
+			      struct pvfs_filename *name, int fd, off_t length)
+{
+	NTSTATUS status;
+	DATA_BLOB blob;
+	/* we have to load the existing stream, then modify, then save */
+	status = pvfs_xattr_load(pvfs, name, name->full_name, fd, XATTR_DOSSTREAM_PREFIX,
+				 name->stream_name, length, &blob);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	if (length <= blob.length) {
+		blob.length = length;
+	} else if (length > blob.length) {
+		blob.data = talloc_realloc(blob.data, blob.data, length);
+		if (blob.data == NULL) {
+			return NT_STATUS_NO_MEMORY;
+		}
+		memset(blob.data+blob.length, 0, length - blob.length);
+		blob.length = length;
+	}
+
+	status = pvfs_xattr_save(pvfs, name->full_name, fd, XATTR_DOSSTREAM_PREFIX,
+				 name->stream_name, &blob);
+	data_blob_free(&blob);
+
+	if (NT_STATUS_IS_OK(status)) {
+		status = pvfs_stream_update_size(pvfs, name, fd, blob.length);
+	}
+
+	return status;
+}