[svn-r16473] Purpose: fix problems related to 'self-referential' attributes

Description:
When an attribute was created with a datatype or dataspace that was shared in
the same object header that the attribute was in, the attribute could not be
deleted.  Changes made to ensure that the attribute can be deleted both when the
attribute is in the object header and when it is shared in the heap.  Object
header message decode routines now take an "open_oh" parameter to enable them to
avoid opening the same object header twice.

Tested: jam, smirom (h5committest)

1 files changed, 34 insertions, 11 deletions

diff --git a/src/H5Oshared.c b/src/H5Oshared.c
index 062443a..e22a105 100644
--- a/src/H5Oshared.c
+++ b/src/H5Oshared.c
@@ -107,7 +107,7 @@
  *-------------------------------------------------------------------------
  */
 static void *
-H5O_shared_read(H5F_t *f, hid_t dxpl_id, unsigned *ioflags,
+H5O_shared_read(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, unsigned *ioflags,
     const H5O_shared_t *shared, const H5O_msg_class_t *type)
 {
     H5HF_t *fheap = NULL;
@@ -159,7 +159,7 @@ H5O_shared_read(H5F_t *f, hid_t dxpl_id, unsigned *ioflags,
             HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "can't read message from fractal heap.")
 
         /* Decode the message */
-        if(NULL == (ret_value = (type->decode)(f, dxpl_id, 0, ioflags, mesg_ptr)))
+        if(NULL == (ret_value = (type->decode)(f, dxpl_id, open_oh, 0, ioflags, mesg_ptr)))
             HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, NULL, "can't decode shared message.")
     } /* end if */
     else {
@@ -167,12 +167,22 @@ H5O_shared_read(H5F_t *f, hid_t dxpl_id, unsigned *ioflags,
 
         HDassert(shared->type == H5O_SHARE_TYPE_COMMITTED);
 
-        /* Get the shared message from an object header */
+        /* Build the object location for the shared message's object header */
         oloc.file = f;
         oloc.addr = shared->u.loc.oh_addr;
         oloc.holding_file = FALSE;
-        if(NULL == (ret_value = H5O_msg_read(&oloc, type->id, NULL, dxpl_id)))
-            HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to read message")
+
+        if(open_oh && oloc.addr == H5O_OH_GET_ADDR(open_oh)) {
+            /* The shared message is in the already opened object header.  This
+             * is possible, for example, if an attribute's datatype is shared in
+             * the same object header the attribute is in.  Read the message
+             * directly. */
+            if(NULL == (ret_value = H5O_msg_read_oh(f, dxpl_id, open_oh, type->id, NULL)))
+                HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to read message")
+        } else
+            /* The shared message is in another object header */
+            if(NULL == (ret_value = H5O_msg_read(&oloc, type->id, NULL, dxpl_id)))
+                HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to read message")
     } /* end else */
 
     /* Mark the message as shared */
@@ -228,7 +238,7 @@ H5O_shared_link_adj(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
         H5O_loc_t oloc;         /* Location for object header where message is stored */
 
         /*
-         * The shared message is stored in some other object header.
+         * The shared message is stored in some object header.
          * The other object header must be in the same file as the
          * new object header. Adjust the reference count on that
          * object header.
@@ -236,13 +246,26 @@ H5O_shared_link_adj(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
         if(shared->file->shared != f->shared)
             HGOTO_ERROR(H5E_LINK, H5E_CANTINIT, FAIL, "interfile hard links are not allowed")
 
-        /* Get the shared message from an object header */
+        /* Build the object location for the shared message's object header */
         oloc.file = f;
         oloc.addr = shared->u.loc.oh_addr;
         oloc.holding_file = FALSE;
 
-        if(H5O_link(&oloc, adjust, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust shared object link count")
+        if(open_oh && oloc.addr == H5O_OH_GET_ADDR(open_oh)) {
+            /* The shared message is in the already opened object header.  This
+             * is possible, for example, if an attribute's datatype is shared in
+             * the same object header the attribute is in.  Adjust the link
+             * count directly. */
+            unsigned oh_flags = H5AC__NO_FLAGS_SET; /* This is used only to satisfy H5O_link_oh */
+
+            if(H5O_link_oh(f, adjust, dxpl_id, open_oh, &oh_flags) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust shared object link count")
+
+            HDassert(!(oh_flags & H5AC__DELETED_FLAG));
+        } else
+            /* The shared message is in another object header */
+            if(H5O_link(&oloc, adjust, dxpl_id) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust shared object link count")
     } /* end if */
     else {
         HDassert(shared->type == H5O_SHARE_TYPE_SOHM || shared->type == H5O_SHARE_TYPE_HERE);
@@ -277,7 +300,7 @@ done:
  *-------------------------------------------------------------------------
  */
 void *
-H5O_shared_decode(H5F_t *f, hid_t dxpl_id, unsigned *ioflags,
+H5O_shared_decode(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh, unsigned *ioflags,
     const uint8_t *buf, const H5O_msg_class_t *type)
 {
     H5O_shared_t sh_mesg;       /* Shared message info */
@@ -344,7 +367,7 @@ H5O_shared_decode(H5F_t *f, hid_t dxpl_id, unsigned *ioflags,
     sh_mesg.msg_type_id = type->id;
 
     /* Retrieve actual message, through decoded shared message info */
-    if(NULL == (ret_value = H5O_shared_read(f, dxpl_id, ioflags, &sh_mesg, type)))
+    if(NULL == (ret_value = H5O_shared_read(f, dxpl_id, open_oh, ioflags, &sh_mesg, type)))
         HGOTO_ERROR(H5E_OHDR, H5E_READERROR, NULL, "unable to retrieve native message")
 
 done: