[svn-r24993] Purpose:

Adds write tracking to the core VFD, which can be configured
via the H5Pset/get_core_write_tracking() API call. When enabled
and writing to the backing store is enabled, this feature will
track writes and only write out the changed bytes on flush/close.

Tested on:
    32-bit LE linux (jam) w/ Fortran and C++
    64-bit BE linux (ostrich)
    64-bit Darwin 12.5.0 (kite)

All were tested using the core VFD w/ paging on (core_paged
in the VFD list). Make check-vfd was also tested on jam.

1 files changed, 98 insertions, 3 deletions

diff --git a/src/H5Pfapl.c b/src/H5Pfapl.c
index a4c09e5..c217acb 100644
--- a/src/H5Pfapl.c
+++ b/src/H5Pfapl.c
@@ -160,7 +160,16 @@
 #define H5F_ACS_FILE_IMAGE_INFO_DEL             H5P_file_image_info_del
 #define H5F_ACS_FILE_IMAGE_INFO_COPY            H5P_file_image_info_copy
 #define H5F_ACS_FILE_IMAGE_INFO_CLOSE           H5P_file_image_info_close
-
+/* Definition of core VFD write tracking flag */
+#define H5F_ACS_CORE_WRITE_TRACKING_FLAG_SIZE   sizeof(hbool_t)
+#define H5F_ACS_CORE_WRITE_TRACKING_FLAG_DEF    FALSE
+#define H5F_ACS_CORE_WRITE_TRACKING_FLAG_ENC    H5P__encode_hbool_t
+#define H5F_ACS_CORE_WRITE_TRACKING_FLAG_DEC    H5P__decode_hbool_t
+/* Definition of core VFD write tracking page size */
+#define H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_SIZE      sizeof(size_t)
+#define H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_DEF       524288
+#define H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_ENC       H5P__encode_size_t
+#define H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_DEC       H5P__decode_size_t
 
 /******************/
 /* Local Typedefs */
@@ -246,8 +255,9 @@ static const H5FD_mem_t H5F_def_mem_type_g = H5F_ACS_MULTI_TYPE_DEF;
 static const hbool_t H5F_def_latest_format_g = H5F_ACS_LATEST_FORMAT_DEF;          /* Default setting for "use the latest version of the format" flag */
 static const hbool_t H5F_def_want_posix_fd_g = H5F_ACS_WANT_POSIX_FD_DEF;          /* Default setting for retrieving 'handle' from core VFD */
 static const unsigned H5F_def_efc_size_g = H5F_ACS_EFC_SIZE_DEF;                   /* Default external file cache size */
-static const H5FD_file_image_info_t H5F_def_file_image_info_g = H5F_ACS_FILE_IMAGE_INFO_DEF;  /* Default file image info and callbacks */
-
+static const H5FD_file_image_info_t H5F_def_file_image_info_g = H5F_ACS_FILE_IMAGE_INFO_DEF;                 /* Default file image info and callbacks */
+static const hbool_t H5F_def_core_write_tracking_flag_g = H5F_ACS_CORE_WRITE_TRACKING_FLAG_DEF;              /* Default setting for core VFD write tracking */
+static const size_t H5F_def_core_write_tracking_page_size_g = H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_DEF;     /* Default core VFD write tracking page size */
 
 
 /*-------------------------------------------------------------------------
@@ -397,6 +407,18 @@ H5P_facc_reg_prop(H5P_genclass_t *pclass)
             H5F_ACS_FILE_IMAGE_INFO_DEL, H5F_ACS_FILE_IMAGE_INFO_COPY, NULL, H5F_ACS_FILE_IMAGE_INFO_CLOSE) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
 
+    /* Register the core VFD backing store write tracking flag */
+    if(H5P_register_real(pclass, H5F_ACS_CORE_WRITE_TRACKING_FLAG_NAME, H5F_ACS_CORE_WRITE_TRACKING_FLAG_SIZE, &H5F_def_core_write_tracking_flag_g , 
+            NULL, NULL, NULL, H5F_ACS_CORE_WRITE_TRACKING_FLAG_ENC, H5F_ACS_CORE_WRITE_TRACKING_FLAG_DEC, 
+            NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
+
+    /* Register the size of the core VFD backing store page size */
+    if(H5P_register_real(pclass, H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_NAME, H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_SIZE, &H5F_def_core_write_tracking_page_size_g , 
+            NULL, NULL, NULL, H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_ENC, H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_DEC, 
+            NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5P_facc_reg_prop() */
@@ -2980,3 +3002,76 @@ H5P__facc_multi_type_dec(const void **_pp, void *_value)
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5P__facc_multi_type_dec() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5Pset_core_write_tracking
+ *
+ * Purpose:	Enables/disables core VFD write tracking and page
+ *              aggregation size.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Pset_core_write_tracking(hid_t plist_id, hbool_t is_enabled, size_t page_size)
+{
+    H5P_genplist_t *plist;        /* Property list pointer */
+    herr_t ret_value = SUCCEED;   /* return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE3("e", "ibz", plist_id, is_enabled, page_size);
+
+    /* Get the plist structure */
+    if(NULL == (plist = H5P_object_verify(plist_id, H5P_FILE_ACCESS)))
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
+
+    /* Set values */
+    if(H5P_set(plist, H5F_ACS_CORE_WRITE_TRACKING_FLAG_NAME, &is_enabled) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set core VFD write tracking flag")
+    if(H5P_set(plist, H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_NAME, &page_size) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set core VFD write tracking page size")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5Pget_core_write_tracking
+ *
+ * Purpose:	Gets information about core VFD write tracking and page
+ *              aggregation size.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Pget_core_write_tracking(hid_t plist_id, hbool_t *is_enabled, size_t *page_size)
+{
+    H5P_genplist_t *plist;      /* Property list pointer */
+    herr_t ret_value = SUCCEED;   /* return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE3("e", "i*b*z", plist_id, is_enabled, page_size);
+
+    /* Get the plist structure */
+    if(NULL == (plist = H5P_object_verify(plist_id, H5P_FILE_ACCESS)))
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
+
+    /* Get values */
+    if(is_enabled) {
+        if(H5P_get(plist, H5F_ACS_CORE_WRITE_TRACKING_FLAG_NAME, is_enabled) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get core VFD write tracking flag")
+    } /* end if */
+
+    if(page_size) {
+        if(H5P_get(plist, H5F_ACS_CORE_WRITE_TRACKING_PAGE_SIZE_NAME, page_size) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get core VFD write tracking page size")
+    } /* end if */
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}
+