gfapi: API/library for accessing gluster volumes

Change-Id: Ie4cbcf91b58218bebf23cf951c313aceeb29f311
BUG: 839950
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-on: http://review.gluster.com/3664
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>
Reviewed-by: Bharata B Rao <bharata.rao@gmail.com>

1 files changed, 244 insertions, 0 deletions

diff --git a/api/src/glfs-resolve.c b/api/src/glfs-resolve.c
new file mode 100644
index 00000000000..c03c4154db0
--- /dev/null
+++ b/api/src/glfs-resolve.c
@@ -0,0 +1,244 @@
+/*
+  Copyright (c) 2012 Red Hat, Inc. <http://www.redhat.com>
+  This file is part of GlusterFS.
+
+  This file is licensed to you under your choice of the GNU Lesser
+  General Public License, version 3 or any later version (LGPLv3 or
+  later), or the GNU General Public License, version 2 (GPLv2), in all
+  cases as published by the Free Software Foundation.
+*/
+
+
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <inttypes.h>
+#include <limits.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "glusterfs.h"
+#include "logging.h"
+#include "stack.h"
+#include "event.h"
+#include "glfs-mem-types.h"
+#include "common-utils.h"
+#include "syncop.h"
+#include "call-stub.h"
+
+#include "glfs-internal.h"
+
+
+void
+glfs_first_lookup (xlator_t *subvol)
+{
+	loc_t  loc = {0, };
+	int    ret = -1;
+
+	loc.inode = subvol->itable->root;
+	memset (loc.gfid, 0, 16);
+	loc.gfid[15] = 1;
+	loc.path = "/";
+	loc.name = "";
+
+	ret = syncop_lookup (subvol, &loc, 0, 0, 0, 0);
+
+	gf_log (subvol->name, GF_LOG_DEBUG, "first lookup complete %d", ret);
+
+	return;
+}
+
+
+int
+glfs_loc_touchup (loc_t *loc)
+{
+	char *path = NULL;
+	int   ret = -1;
+	char *bn = NULL;
+
+	ret = inode_path (loc->parent, loc->name, &path);
+
+	loc->path = path;
+
+	if (ret < 0 || !path) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	bn = strrchr (path, '/');
+	if (bn)
+		bn++;
+	loc->name = bn;
+	ret = 0;
+out:
+	return ret;
+}
+
+
+inode_t *
+glfs_resolve_component (struct glfs *fs, xlator_t *subvol, inode_t *parent,
+			const char *component, struct iatt *iatt)
+{
+	loc_t        loc = {0, };
+	inode_t     *inode = NULL;
+	int          reval = 0;
+	int          ret = -1;
+	int          glret = -1;
+	struct iatt  ciatt = {0, };
+	uuid_t       gfid;
+	dict_t      *xattr_req = NULL;
+
+	loc.name = component;
+
+	loc.parent = inode_ref (parent);
+	uuid_copy (loc.pargfid, parent->gfid);
+
+	xattr_req = dict_new ();
+	if (!xattr_req) {
+		errno = ENOMEM;
+		goto out;
+	}
+
+	ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
+	if (ret) {
+		errno = ENOMEM;
+		goto out;
+	}
+
+	loc.inode = inode_grep (parent->table, parent, component);
+
+	if (loc.inode) {
+		uuid_copy (loc.gfid, loc.inode->gfid);
+		reval = 1;
+	} else {
+		uuid_generate (gfid);
+		loc.inode = inode_new (parent->table);
+	}
+
+	if (!loc.inode)
+		goto out;
+
+
+	glret = glfs_loc_touchup (&loc);
+	if (glret < 0) {
+		ret = -1;
+		goto out;
+	}
+
+	ret = syncop_lookup (subvol, &loc, xattr_req, &ciatt, NULL, NULL);
+	if (ret && reval) {
+		inode_unref (loc.inode);
+		loc.inode = inode_new (parent->table);
+		if (!loc.inode)
+			goto out;
+		uuid_generate (gfid);
+		ret = syncop_lookup (subvol, &loc, xattr_req, &ciatt,
+				     NULL, NULL);
+	}
+	if (ret)
+		goto out;
+
+	inode = inode_link (loc.inode, loc.parent, component, &ciatt);
+	if (inode)
+		inode_lookup (inode);
+	if (iatt)
+		*iatt = ciatt;
+out:
+	if (xattr_req)
+		dict_destroy (xattr_req);
+
+	loc_wipe (&loc);
+
+	return inode;
+}
+
+
+int
+glfs_resolve (struct glfs *fs, xlator_t *subvol, const char *origpath,
+	      loc_t *loc, struct iatt *iatt)
+{
+	inode_t    *inode = NULL;
+	inode_t    *parent = NULL;
+	char       *saveptr = NULL;
+	char       *path = NULL;
+	char       *component = NULL;
+	char       *next_component = NULL;
+	int         ret = -1;
+	struct iatt ciatt = {0, };
+
+	path = gf_strdup (origpath);
+	if (!path) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	parent = NULL;
+	inode = inode_ref (subvol->itable->root);
+
+	for (component = strtok_r (path, "/", &saveptr);
+	     component; component = next_component) {
+
+		next_component = strtok_r (NULL, "/", &saveptr);
+
+		if (parent)
+			inode_unref (parent);
+
+		parent = inode;
+
+		inode = glfs_resolve_component (fs, subvol, parent,
+						component, &ciatt);
+		if (!inode)
+			break;
+
+		if (!next_component)
+			break;
+
+		if (!IA_ISDIR (ciatt.ia_type)) {
+			/* next_component exists and this component is
+			   not a directory
+			*/
+			inode_unref (inode);
+			inode = NULL;
+			ret = -1;
+			errno = ENOTDIR;
+			break;
+		}
+	}
+
+	if (parent && next_component)
+		/* resolution failed mid-way */
+		goto out;
+
+	/* At this point, all components up to the last parent directory
+	   have been resolved successfully (@parent). Resolution of basename
+	   might have failed (@inode) if at all.
+	*/
+
+	loc->parent = parent;
+	if (parent) {
+		uuid_copy (loc->pargfid, parent->gfid);
+		loc->name = component;
+	}
+
+	loc->inode = inode;
+	if (inode) {
+		uuid_copy (loc->gfid, inode->gfid);
+		if (iatt)
+			*iatt = ciatt;
+		ret = 0;
+	}
+
+	glfs_loc_touchup (loc);
+out:
+	GF_FREE (path);
+
+	/* do NOT loc_wipe here as only last component might be missing */
+
+	return ret;
+}
+