libgfapi: Store and restore THIS in every API exposed by libgfapi

Storing and restoring THIS:
When the APIs exposed by libgfapi are called by other xlators like
snapview server etc. the THIS value is overwritten to contain the
THIS of libgfapi(viz libgfapi master xlator). Hence using 'THIS'
in any xlator after calling libgfapi API will lead to issues.
One such issue was uncovered in snapview and the patch
http://review.gluster.org/#/c/9469/ was sent to workaround this issue.

Hence, storing and restoring THIS, at the entry and exit of every API
exposed by libgfapi.

Change-Id: I6f330dde25e7700fb26339d667a7ccd193ec6ba0
BUG: 1210934
Signed-off-by: Poornima G <pgurusid@redhat.com>
Reviewed-on: http://review.gluster.org/9797
Reviewed-by: Raghavendra Talur <rtalur@redhat.com>
Reviewed-by: soumya k <skoduri@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>

1 files changed, 155 insertions, 40 deletions

diff --git a/api/src/glfs-handleops.c b/api/src/glfs-handleops.c
index 2793e1cb118..8ff23ecff03 100644
--- a/api/src/glfs-handleops.c
+++ b/api/src/glfs-handleops.c
@@ -72,13 +72,15 @@ pub_glfs_h_lookupat (struct glfs *fs, struct glfs_object *parent,
         struct glfs_object      *object = NULL;
         loc_t                    loc = {0, };
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
-        if ((fs == NULL) || (path == NULL)) {
+        if (path == NULL) {
                 errno = EINVAL;
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -116,6 +118,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return object;
 }
 
@@ -130,13 +135,15 @@ pub_glfs_h_statfs (struct glfs *fs, struct glfs_object *object,
         inode_t         *inode = NULL;
         loc_t            loc = {0, };
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
         if ((fs == NULL) || (object == NULL || statvfs == NULL)) {
                 errno = EINVAL;
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -168,6 +175,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -182,13 +192,15 @@ pub_glfs_h_stat (struct glfs *fs, struct glfs_object *object, struct stat *stat)
         loc_t            loc = {0, };
         struct iatt      iatt = {0, };
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
         if ((fs == NULL) || (object == NULL)) {
                 errno = EINVAL;
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -224,6 +236,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -234,7 +249,7 @@ int
 pub_glfs_h_getattrs (struct glfs *fs, struct glfs_object *object,
                      struct stat *stat)
 {
-        int                      ret = 0;
+        int                      ret = -1;
         xlator_t                *subvol = NULL;
         inode_t                 *inode = NULL;
         struct iatt              iatt = {0, };
@@ -245,7 +260,8 @@ pub_glfs_h_getattrs (struct glfs *fs, struct glfs_object *object,
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -258,6 +274,7 @@ pub_glfs_h_getattrs (struct glfs *fs, struct glfs_object *object,
         /* get/refresh the in arg objects inode in correlation to the xlator */
         inode = glfs_resolve_inode (fs, subvol, object);
         if (!inode) {
+                ret = 0;
                 errno = ESTALE;
                 goto out;
         }
@@ -276,6 +293,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -297,8 +317,6 @@ glfs_h_getxattrs_common (struct glfs *fs, struct glfs_object *object,
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
-
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
         if (!subvol) {
@@ -336,7 +354,7 @@ int
 pub_glfs_h_getxattrs (struct glfs *fs, struct glfs_object *object,
                       const char *name, void *value, size_t size)
 {
-        int                 ret = 0;
+        int                    ret   = -1;
         dict_t                *xattr = NULL;
 
         /* validate in args */
@@ -345,6 +363,9 @@ pub_glfs_h_getxattrs (struct glfs *fs, struct glfs_object *object,
                 return -1;
         }
 
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
+
         ret = glfs_h_getxattrs_common (fs, object, &xattr, name);
         if (ret)
                 goto out;
@@ -358,6 +379,10 @@ pub_glfs_h_getxattrs (struct glfs *fs, struct glfs_object *object,
 out:
         if (xattr)
                 dict_unref (xattr);
+
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -380,7 +405,8 @@ pub_glfs_h_setattrs (struct glfs *fs, struct glfs_object *object,
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -414,6 +440,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -438,7 +467,8 @@ pub_glfs_h_setxattrs (struct glfs *fs, struct glfs_object *object,
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -480,6 +510,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -501,7 +534,8 @@ pub_glfs_h_removexattrs (struct glfs *fs, struct glfs_object *object,
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -533,6 +567,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -554,7 +591,8 @@ pub_glfs_h_open (struct glfs *fs, struct glfs_object *object, int flags)
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -622,6 +660,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return glfd;
 }
 
@@ -648,7 +689,8 @@ pub_glfs_h_creat (struct glfs *fs, struct glfs_object *parent, const char *path,
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -726,6 +768,7 @@ pub_glfs_h_creat (struct glfs *fs, struct glfs_object *parent, const char *path,
 
 out:
         if (ret && object != NULL) {
+                /* Release the held reference */
                 glfs_h_close (object);
                 object = NULL;
         }
@@ -745,6 +788,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return object;
 }
 
@@ -770,7 +816,8 @@ pub_glfs_h_mkdir (struct glfs *fs, struct glfs_object *parent, const char *path,
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -837,6 +884,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return object;
 }
 
@@ -862,7 +912,8 @@ pub_glfs_h_mknod (struct glfs *fs, struct glfs_object *parent, const char *path,
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -928,6 +979,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return object;
 }
 
@@ -948,7 +1002,8 @@ pub_glfs_h_unlink (struct glfs *fs, struct glfs_object *parent, const char *path
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -995,6 +1050,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -1016,7 +1074,8 @@ pub_glfs_h_opendir (struct glfs *fs, struct glfs_object *object)
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1074,6 +1133,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return glfd;
 }
 
@@ -1094,7 +1156,8 @@ pub_glfs_h_access (struct glfs *fs, struct glfs_object *object, int mask)
 		goto out;
 	}
 
-	__glfs_entry_fs (fs);
+	DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
 	/* get the active volume */
 	subvol = glfs_active_subvol (fs);
@@ -1128,6 +1191,9 @@ out:
 
 	glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
 	return ret;
 }
 
@@ -1185,7 +1251,8 @@ pub_glfs_h_create_from_handle (struct glfs *fs, unsigned char *handle, int len,
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        DECLARE_OLD_THIS;
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1255,6 +1322,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return object;
 }
 
@@ -1264,7 +1334,6 @@ GFAPI_SYMVER_PUBLIC_DEFAULT(glfs_h_create_from_handle, 3.4.2);
 int
 pub_glfs_h_close (struct glfs_object *object)
 {
-        /* Release the held reference */
         inode_unref (object->inode);
         GF_FREE (object);
 
@@ -1282,13 +1351,15 @@ pub_glfs_h_truncate (struct glfs *fs, struct glfs_object *object, off_t offset)
         xlator_t           *subvol = NULL;
         inode_t            *inode = NULL;
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
-        if ((fs == NULL) || (object == NULL)) {
+        if (object == NULL) {
                 errno = EINVAL;
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1323,6 +1394,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -1342,14 +1416,16 @@ pub_glfs_h_symlink (struct glfs *fs, struct glfs_object *parent,
         dict_t             *xattr_req = NULL;
         struct glfs_object *object = NULL;
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
-        if ((fs == NULL) || (parent == NULL) || (name == NULL) ||
+        if ((parent == NULL) || (name == NULL) ||
                 (data == NULL)) {
                 errno = EINVAL;
                 return NULL;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1421,6 +1497,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return object;
 }
 
@@ -1437,13 +1516,15 @@ pub_glfs_h_readlink (struct glfs *fs, struct glfs_object *object, char *buf,
         inode_t            *inode = NULL;
         char               *linkval = NULL;
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
-        if ((fs == NULL) || (object == NULL) || (buf == NULL)) {
+        if ((object == NULL) || (buf == NULL)) {
                 errno = EINVAL;
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1481,6 +1562,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -1498,14 +1582,16 @@ pub_glfs_h_link (struct glfs *fs, struct glfs_object *linksrc,
         loc_t               oldloc = {0, };
         loc_t               newloc = {0, };
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
-        if ((fs == NULL) || (linksrc == NULL) || (parent == NULL) ||
+        if ((linksrc == NULL) || (parent == NULL) ||
                 (name == NULL)) {
                 errno = EINVAL;
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1570,6 +1656,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -1590,14 +1679,16 @@ pub_glfs_h_rename (struct glfs *fs, struct glfs_object *olddir,
         struct iatt         oldiatt = {0, };
         struct iatt         newiatt = {0, };
 
+        DECLARE_OLD_THIS;
+
         /* validate in args */
-        if ((fs == NULL) || (olddir == NULL) || (oldname == NULL) ||
+        if ((olddir == NULL) || (oldname == NULL) ||
                 (newdir == NULL) || (newname == NULL)) {
                 errno = EINVAL;
                 return -1;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
@@ -1667,6 +1758,9 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -1777,19 +1871,21 @@ pub_glfs_h_poll_upcall (struct glfs *fs, struct callback_arg *up_arg)
         int                                 ret             = -1;
         struct gf_upcall                    *upcall_data    = NULL;
 
-        if (!fs || !up_arg) {
+        DECLARE_OLD_THIS;
+
+        if (!up_arg) {
                 errno = EINVAL;
                 goto err;
         }
 
-        __glfs_entry_fs (fs);
+        __GLFS_ENTRY_VALIDATE_FS (fs, err);
 
         /* get the active volume */
         subvol = glfs_active_subvol (fs);
 
         if (!subvol) {
                 errno = EIO;
-                goto err;
+                goto restore;
         }
 
         /* Ideally applications should stop polling before calling
@@ -1871,6 +1967,8 @@ out:
 
         glfs_subvol_done (fs, subvol);
 
+restore:
+        __GLFS_EXIT_FS;
 err:
         return ret;
 }
@@ -1890,23 +1988,32 @@ pub_glfs_h_acl_set (struct glfs *fs, struct glfs_object *object,
         const char *acl_key = NULL;
         ssize_t acl_len = 0;
 
-        if (!fs || !object || !acl) {
+        DECLARE_OLD_THIS;
+
+        if (!object || !acl) {
                 errno = EINVAL;
                 return ret;
         }
 
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
+
         acl_key = gf_posix_acl_get_key (type);
         if (!acl_key)
-                return ret;
+                goto out;
 
         acl_s = acl_to_any_text (acl, NULL, ',',
                                  TEXT_ABBREVIATE | TEXT_NUMERIC_IDS);
         if (!acl_s)
-                return ret;
+                goto out;
 
         ret = pub_glfs_h_setxattrs (fs, object, acl_key, acl_s, acl_len, 0);
 
         acl_free (acl_s);
+
+out:
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return ret;
 }
 
@@ -1920,18 +2027,22 @@ pub_glfs_h_acl_get (struct glfs *fs, struct glfs_object *object,
         dict_t *xattr = NULL;
         const char *acl_key = NULL;
 
-        if (!fs || !object) {
+        DECLARE_OLD_THIS;
+
+        if (!object) {
                 errno = EINVAL;
                 return NULL;
         }
 
+        __GLFS_ENTRY_VALIDATE_FS (fs, invalid_fs);
+
         acl_key = gf_posix_acl_get_key (type);
         if (!acl_key)
-                return NULL;
+                goto out;
 
         ret = glfs_h_getxattrs_common (fs, object, &xattr, acl_key);
         if (ret)
-                return NULL;
+                goto out;
 
         ret = dict_get_str (xattr, (char *)acl_key, &acl_s);
         if (ret == -1)
@@ -1941,6 +2052,10 @@ pub_glfs_h_acl_get (struct glfs *fs, struct glfs_object *object,
 
 out:
         GF_FREE (acl_s);
+
+        __GLFS_EXIT_FS;
+
+invalid_fs:
         return acl;
 }
 #else /* !HAVE_ACL_LIBACL_H */