r4700: first attempt at a composite async function, smb_composite_loadfile(),

which combineds ntcreatex, readx and close into a single call that
behaves just like a normal libcli async call.
(This used to be commit 516f68fb054f0717f0429e031aa820776ecc6597)

2 files changed, 361 insertions, 0 deletions

diff --git a/source4/libcli/composite/composite.h b/source4/libcli/composite/composite.h
new file mode 100644
index 0000000000..895c88a4f6
--- /dev/null
+++ b/source4/libcli/composite/composite.h
@@ -0,0 +1,72 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   SMB composite request interfaces
+
+   Copyright (C) Andrew Tridgell 2005
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/*
+  this defines the structures associated with "composite"
+  requests. Composite requests are libcli requests that are internally
+  implemented as multiple libcli/raw/ calls, but can be treated as a
+  single call via these composite calls. The composite calls are
+  particularly designed to be used in async applications
+*/
+
+
+struct smbcli_composite {
+	/* the external state - will be queried by the caller */
+	enum smbcli_request_state state;
+
+	/* the internal stage */
+	uint16_t stage;
+
+	/* the currently running sub-request */
+	struct smbcli_request *req;
+
+	/* the current requests parameter block */
+	void *req_parms;
+
+	/* the parameters of the whole composite function */
+	void *composite_parms;
+
+	/* status code when finished */
+	NTSTATUS status;
+
+	/* information on what to do on completion */
+	struct {
+		void (*fn)(struct smbcli_composite *);
+		void *private;
+	} async;
+	
+};
+
+
+/*
+  a composite open/read(s)/close request that loads a whole file
+  into memory. Used as a demo of the composite system.
+*/
+struct smb_composite_loadfile {
+	struct {
+		const char *fname;
+	} in;
+	struct {
+		uint8_t *data;
+		uint32_t size;
+	} out;
+};
diff --git a/source4/libcli/composite/loadfile.c b/source4/libcli/composite/loadfile.c
new file mode 100644
index 0000000000..1bf1fd5403
--- /dev/null
+++ b/source4/libcli/composite/loadfile.c
@@ -0,0 +1,289 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   Copyright (C) Andrew Tridgell 2005
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+/*
+  a composite API for loading a whole file into memory
+*/
+
+#include "includes.h"
+#include "libcli/raw/libcliraw.h"
+#include "libcli/composite/composite.h"
+#include "librpc/gen_ndr/ndr_security.h"
+
+/* the stages of this call */
+enum loadfile_stage {LOADFILE_OPEN, LOADFILE_READ, LOADFILE_CLOSE};
+
+
+static void loadfile_handler(struct smbcli_request *req);
+
+
+/*
+  setup for the close
+*/
+static NTSTATUS setup_close(struct smbcli_composite *c, 
+			    struct smbcli_tree *tree, uint16_t fnum)
+{
+	union smb_close *io_close;
+
+	/* nothing to read, setup the close */
+	io_close = talloc(c, union smb_close);
+	NT_STATUS_HAVE_NO_MEMORY(io_close);
+	
+	io_close->close.level = RAW_CLOSE_CLOSE;
+	io_close->close.in.fnum = fnum;
+	io_close->close.in.write_time = 0;
+
+	c->req = smb_raw_close_send(tree, io_close);
+	NT_STATUS_HAVE_NO_MEMORY(c->req);
+
+	/* call the handler again when the close is done */
+	c->stage = LOADFILE_CLOSE;
+	c->req->async.fn = loadfile_handler;
+	c->req->async.private = c;
+	c->req_parms = io_close;
+
+	return NT_STATUS_OK;
+}
+
+/*
+  called when the open is done - pull the results and setup for the
+  first readx, or close if the file is zero size
+*/
+static NTSTATUS loadfile_open(struct smbcli_composite *c, 
+			      struct smb_composite_loadfile *io)
+{
+	union smb_open *io_open = c->req_parms;
+	struct smbcli_tree *tree = c->req->tree;
+	union smb_read *io_read;
+	NTSTATUS status;
+
+	status = smb_raw_open_recv(c->req, c, io_open);
+	NT_STATUS_NOT_OK_RETURN(status);
+	
+	/* don't allow stupidly large loads */
+	if (io_open->ntcreatex.out.size > 100*1000*1000) {
+		return NT_STATUS_INSUFFICIENT_RESOURCES;
+	}
+
+	/* allocate space for the file data */
+	io->out.size = io_open->ntcreatex.out.size;
+	io->out.data = talloc_array(c, uint8_t, io->out.size);
+	NT_STATUS_HAVE_NO_MEMORY(io->out.data);
+
+	if (io->out.size == 0) {
+		return setup_close(c, tree, io_open->ntcreatex.out.fnum);
+	}
+
+	/* setup for the read */
+	io_read = talloc(c, union smb_read);
+	NT_STATUS_HAVE_NO_MEMORY(io_read);
+	
+	io_read->readx.level        = RAW_READ_READX;
+	io_read->readx.in.fnum      = io_open->ntcreatex.out.fnum;
+	io_read->readx.in.offset    = 0;
+	io_read->readx.in.mincnt    = MIN(32768, io->out.size);
+	io_read->readx.in.maxcnt    = io_read->readx.in.mincnt;
+	io_read->readx.in.remaining = 0;
+	io_read->readx.out.data     = io->out.data;
+
+	c->req = smb_raw_read_send(tree, io_read);
+	NT_STATUS_HAVE_NO_MEMORY(c->req);
+
+	/* call the handler again when the first read is done */
+	c->stage = LOADFILE_READ;
+	c->req->async.fn = loadfile_handler;
+	c->req->async.private = c;
+	c->req_parms = io_read;
+	talloc_free(io_open);
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  called when a read is done - pull the results and setup for the
+  next read, or close if the file is all done
+*/
+static NTSTATUS loadfile_read(struct smbcli_composite *c, 
+			      struct smb_composite_loadfile *io)
+{
+	union smb_read *io_read = c->req_parms;
+	struct smbcli_tree *tree = c->req->tree;
+	NTSTATUS status;
+
+	status = smb_raw_read_recv(c->req, io_read);
+	NT_STATUS_NOT_OK_RETURN(status);
+	
+	/* we might be done */
+	if (io_read->readx.in.offset +
+	    io_read->readx.out.nread == io->out.size) {
+		return setup_close(c, tree, io_read->readx.in.fnum);
+	}
+
+	/* setup for the next read */
+	io_read->readx.in.offset += io_read->readx.out.nread;
+	io_read->readx.in.mincnt = MIN(32768, io->out.size - io_read->readx.in.offset);
+	io_read->readx.out.data = io->out.data + io_read->readx.in.offset;
+
+	c->req = smb_raw_read_send(tree, io_read);
+	NT_STATUS_HAVE_NO_MEMORY(c->req);
+
+	/* call the handler again when the read is done */
+	c->req->async.fn = loadfile_handler;
+	c->req->async.private = c;
+
+	return NT_STATUS_OK;
+}
+
+/*
+  called when the close is done, check the status and cleanup
+*/
+static NTSTATUS loadfile_close(struct smbcli_composite *c, 
+			       struct smb_composite_loadfile *io)
+{
+	NTSTATUS status;
+
+	status = smbcli_request_simple_recv(c->req);
+	NT_STATUS_NOT_OK_RETURN(status);
+	
+	c->state = SMBCLI_REQUEST_DONE;
+	if (c->async.fn) {
+		c->async.fn(c);
+	}
+
+	return NT_STATUS_OK;
+}
+						     
+
+/*
+  handler for completion of a sub-request in loadfile
+*/
+static void loadfile_handler(struct smbcli_request *req)
+{
+	struct smbcli_composite *c = req->async.private;
+	struct smb_composite_loadfile *io = c->composite_parms;
+
+	/* when this handler is called, the stage indicates what
+	   call has just finished */
+	switch (c->stage) {
+	case LOADFILE_OPEN:
+		c->status = loadfile_open(c, io);
+		break;
+
+	case LOADFILE_READ:
+		c->status = loadfile_read(c, io);
+		break;
+
+	case LOADFILE_CLOSE:
+		c->status = loadfile_close(c, io);
+		break;
+	}
+
+	if (!NT_STATUS_IS_OK(c->status)) {
+		c->state = SMBCLI_REQUEST_ERROR;
+		if (c->async.fn) {
+			c->async.fn(c);
+		}
+	}
+}
+
+/*
+  composite loadfile call - does an openx followed by a number of readx calls,
+  followed by a close
+*/
+struct smbcli_composite *smb_composite_loadfile_send(struct smbcli_tree *tree, 
+						     struct smb_composite_loadfile *io)
+{
+	struct smbcli_composite *c;
+	union smb_open *io_open;
+
+	c = talloc_zero(tree, struct smbcli_composite);
+	if (c == NULL) goto failed;
+
+	c->state = SMBCLI_REQUEST_SEND;
+	c->stage = LOADFILE_OPEN;
+	c->composite_parms = io;
+
+	/* setup for the open */
+	io_open = talloc_zero(c, union smb_open);
+	if (io_open == NULL) goto failed;
+	
+	io_open->ntcreatex.level               = RAW_OPEN_NTCREATEX;
+	io_open->ntcreatex.in.flags            = NTCREATEX_FLAGS_EXTENDED;
+	io_open->ntcreatex.in.access_mask      = SEC_FILE_READ_DATA;
+	io_open->ntcreatex.in.file_attr        = FILE_ATTRIBUTE_NORMAL;
+	io_open->ntcreatex.in.share_access     = NTCREATEX_SHARE_ACCESS_READ | NTCREATEX_SHARE_ACCESS_WRITE;
+	io_open->ntcreatex.in.open_disposition = NTCREATEX_DISP_OPEN;
+	io_open->ntcreatex.in.impersonation    = NTCREATEX_IMPERSONATION_ANONYMOUS;
+	io_open->ntcreatex.in.fname            = io->in.fname;
+
+	/* send the open on its way */
+	c->req = smb_raw_open_send(tree, io_open);
+	if (c->req == NULL) goto failed;
+
+	/* setup the callback handler */
+	c->req->async.fn = loadfile_handler;
+	c->req->async.private = c;
+	c->req_parms = io_open;
+
+	return c;
+
+failed:
+	talloc_free(c);
+	return NULL;
+}
+
+
+/*
+  composite loadfile call - recv side
+*/
+NTSTATUS smb_composite_loadfile_recv(struct smbcli_composite *c, TALLOC_CTX *mem_ctx)
+{
+	NTSTATUS status;
+
+	if (!c) return NT_STATUS_NO_MEMORY;
+
+	while (c->state < SMBCLI_REQUEST_DONE) {
+		if (event_loop_once(c->req->transport->event.ctx) != 0) {
+			return NT_STATUS_UNSUCCESSFUL;
+		}
+	}
+
+	if (NT_STATUS_IS_OK(c->status)) {
+		struct smb_composite_loadfile *io = c->composite_parms;
+		talloc_steal(mem_ctx, io->out.data);
+	}
+
+	status = c->status;
+	talloc_free(c);
+
+	return status;
+}
+
+
+/*
+  composite loadfile call - sync interface
+*/
+NTSTATUS smb_composite_loadfile(struct smbcli_tree *tree, 
+				TALLOC_CTX *mem_ctx,
+				struct smb_composite_loadfile *io)
+{
+	struct smbcli_composite *c = smb_composite_loadfile_send(tree, io);
+	return smb_composite_loadfile_recv(c, mem_ctx);
+}