HDFFV-10658: 1. moving HDgetenv to dataset initialization stage to reduce the overhead; 2. restoring the retrieval of three vol properties to H5P_get instead of using API context to prepare for Quincey's upcoming refactoring work.

1 files changed, 26 insertions, 14 deletions

diff --git a/src/H5Dint.c b/src/H5Dint.c
index ae9a40e..7367613 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -43,6 +43,12 @@
 /* Local Typedefs */
 /******************/
 
+/* Type of prefix for file */
+typedef enum {
+    H5D_PREFIX_TYPE_UNKNOWN=0,
+    H5D_PREFIX_TYPE_EXT=1,
+    H5D_PREFIX_TYPE_VDS=2
+} H5D_prefix_type_t;
 
 /********************/
 /* Local Prototypes */
@@ -54,7 +60,7 @@ static herr_t H5D__init_type(H5F_t *file, const H5D_t *dset, hid_t type_id, cons
 static herr_t H5D__cache_dataspace_info(const H5D_t *dset);
 static herr_t H5D__init_space(H5F_t *file, const H5D_t *dset, const H5S_t *space);
 static herr_t H5D__update_oh_info(H5F_t *file, H5D_t *dset, hid_t dapl_id);
-static herr_t H5D__build_file_prefix(const H5D_t *dset, hid_t dapl_id, const char *prefix_type, char **file_prefix);
+static herr_t H5D__build_file_prefix(const H5D_t *dset, H5D_prefix_type_t prefix_type, char **file_prefix);
 static herr_t H5D__open_oid(H5D_t *dataset, hid_t dapl_id);
 static herr_t H5D__init_storage(const H5D_io_info_t *io_info, hbool_t full_overwrite,
         hsize_t old_dim[]);
@@ -112,6 +118,10 @@ static const H5I_class_t H5I_DATASET_CLS[1] = {{
 /* Flag indicating "top" of interface has been initialized */
 static hbool_t H5D_top_package_initialize_s = FALSE;
 
+/* Prefixes of VDS and external file from the environment variables
+ * HDF5_EXTFILE_PREFIX and HDF5_VDS_PREFIX */ 
+static char *H5D_prefix_ext_env = NULL;
+static char *H5D_prefix_vds_env = NULL;
 
 
 /*-------------------------------------------------------------------------
@@ -188,6 +198,10 @@ H5D__init_package(void)
     /* Mark "top" of interface as initialized, too */
     H5D_top_package_initialize_s = TRUE;
 
+    /* Retrieve the prefixes of VDS and external file from the environment variable */
+    H5D_prefix_vds_env = HDgetenv("HDF5_VDS_PREFIX");
+    H5D_prefix_ext_env = HDgetenv("HDF5_EXTFILE_PREFIX");
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__init_package() */
@@ -1080,7 +1094,7 @@ done:
  *--------------------------------------------------------------------------
  */
 static herr_t
-H5D__build_file_prefix(const H5D_t *dset, hid_t dapl_id, const char *prefix_type, char **file_prefix /*out*/)
+H5D__build_file_prefix(const H5D_t *dset, H5D_prefix_type_t prefix_type, char **file_prefix /*out*/)
 {
     char            *prefix = NULL;       /* prefix used to look for the file               */
     char            *filepath = NULL;     /* absolute path of directory the HDF5 file is in */
@@ -1101,15 +1115,15 @@ H5D__build_file_prefix(const H5D_t *dset, hid_t dapl_id, const char *prefix_type
     /* XXX: Future thread-safety note - getenv is not required
      *      to be reentrant.
      */
-    if(HDstrcmp(prefix_type, H5D_ACS_VDS_PREFIX_NAME) == 0) {
-        prefix = HDgetenv("HDF5_VDS_PREFIX");
+    if(H5D_PREFIX_TYPE_VDS == prefix_type) {
+        prefix = H5D_prefix_vds_env;
 
         if(prefix == NULL || *prefix == '\0') {
             if(H5CX_get_vds_prefix(&prefix) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get the prefix for vds file")
         }
-    } else if(HDstrcmp(prefix_type, H5D_ACS_EFILE_PREFIX_NAME) == 0) {
-        prefix = HDgetenv("HDF5_EXTFILE_PREFIX");
+    } else if(H5D_PREFIX_TYPE_EXT == prefix_type) {
+        prefix = H5D_prefix_ext_env;
 
         if(prefix == NULL || *prefix == '\0') {
             if(H5CX_get_ext_file_prefix(&prefix) < 0)
@@ -1324,11 +1338,11 @@ H5D__create(H5F_t *file, hid_t type_id, const H5S_t *space, hid_t dcpl_id,
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to set up flush append property")
 
     /* Set the external file prefix */
-    if(H5D__build_file_prefix(new_dset, dapl_id, H5D_ACS_EFILE_PREFIX_NAME, &new_dset->shared->extfile_prefix) < 0)
+    if(H5D__build_file_prefix(new_dset, H5D_PREFIX_TYPE_EXT, &new_dset->shared->extfile_prefix) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize external file prefix")
 
     /* Set the VDS file prefix */
-    if(H5D__build_file_prefix(new_dset, dapl_id, H5D_ACS_VDS_PREFIX_NAME, &new_dset->shared->vds_prefix) < 0)
+    if(H5D__build_file_prefix(new_dset, H5D_PREFIX_TYPE_VDS, &new_dset->shared->vds_prefix) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize VDS prefix")
 
     /* Add the dataset to the list of opened objects in the file */
@@ -1483,11 +1497,11 @@ H5D_open(const H5G_loc_t *loc, hid_t dapl_id)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, NULL, "can't copy path")
 
     /* Get the external file prefix */
-    if(H5D__build_file_prefix(dataset, dapl_id, H5D_ACS_EFILE_PREFIX_NAME, &extfile_prefix) < 0)
+    if(H5D__build_file_prefix(dataset, H5D_PREFIX_TYPE_EXT, &extfile_prefix) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize external file prefix")
 
     /* Get the VDS prefix */
-    if(H5D__build_file_prefix(dataset, dapl_id, H5D_ACS_VDS_PREFIX_NAME, &vds_prefix) < 0)
+    if(H5D__build_file_prefix(dataset, H5D_PREFIX_TYPE_VDS, &vds_prefix) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize VDS prefix")
 
     /* Check if dataset was already open */
@@ -1550,10 +1564,8 @@ H5D_open(const H5G_loc_t *loc, hid_t dapl_id)
     ret_value = dataset;
 
 done:
-    if(extfile_prefix)
-        extfile_prefix = (char *)H5MM_xfree(extfile_prefix);
-    if(vds_prefix)
-        vds_prefix = (char *)H5MM_xfree(vds_prefix);
+    extfile_prefix = (char *)H5MM_xfree(extfile_prefix);
+    vds_prefix = (char *)H5MM_xfree(vds_prefix);
 
     if(ret_value == NULL) {
         /* Free the location--casting away const*/