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and replace it with new url for COPYING file. Fix 2 lines in java error test expected output file where messages include line numbers changed by reducing the copyright header by 2 lines.
672 lines
24 KiB
C
672 lines
24 KiB
C
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
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* Copyright by The HDF Group. *
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* Copyright by the Board of Trustees of the University of Illinois. *
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* All rights reserved. *
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* *
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* This file is part of HDF5. The full HDF5 copyright notice, including *
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* terms governing use, modification, and redistribution, is contained in *
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* the COPYING file, which can be found at the root of the source code *
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* distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases. *
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* If you do not have access to either file, you may request a copy from *
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* help@hdfgroup.org. *
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* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
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/* This program demonstrates how to create and use "external links" in
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* HDF5.
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*
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* External links point from one HDF5 file to an object (Group, Dataset, or
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* committed Datatype) in another file.
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*/
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#include "hdf5.h"
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#include <string.h>
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#define SOURCE_FILE "extlink_source.h5"
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#define TARGET_FILE "extlink_target.h5"
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#define PREFIX_SOURCE_FILE "extlink_prefix_source.h5"
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#define SOFT_LINK_FILE "soft_link.h5"
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#define SOFT_LINK_NAME "soft_link_to_group"
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#define UD_SOFT_LINK_NAME "ud_soft_link"
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#define TARGET_GROUP "target_group"
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#define UD_SOFT_CLASS 65
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#define HARD_LINK_FILE "hard_link.h5"
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#define HARD_LINK_NAME "hard_link_to_group"
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#define UD_HARD_LINK_NAME "ud_hard_link"
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#define UD_HARD_CLASS 66
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#define PLIST_LINK_PROP "plist_link_prop"
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#define UD_PLIST_CLASS 66
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/* Basic external link example
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*
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* Creates two files and uses an external link to access an object in the
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* second file from the first file.
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*/
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static void extlink_example(void)
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{
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hid_t source_file_id, targ_file_id;
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hid_t group_id, group2_id;
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/* Create two files, a source and a target */
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source_file_id = H5Fcreate(SOURCE_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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targ_file_id = H5Fcreate(TARGET_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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/* Create a group in the target file for the external link to point to. */
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group_id = H5Gcreate2(targ_file_id, "target_group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
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/* Close the group and the target file */
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H5Gclose(group_id);
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/* Create an external link in the source file pointing to the target group.
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* We could instead have created the external link first, then created the
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* group it points to; the order doesn't matter.
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*/
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H5Lcreate_external(TARGET_FILE, "target_group", source_file_id, "ext_link", H5P_DEFAULT, H5P_DEFAULT);
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/* Now we can use the external link to create a new group inside the
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* target group (even though the target file is closed!). The external
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* link works just like a soft link.
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*/
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group_id = H5Gcreate2(source_file_id, "ext_link/new_group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
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/* The group is inside the target file and we can access it normally.
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* Here, group_id and group2_id point to the same group inside the
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* target file.
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*/
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group2_id = H5Gopen2(targ_file_id, "target_group/new_group", H5P_DEFAULT);
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/* Don't forget to close the IDs we opened. */
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H5Gclose(group2_id);
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H5Gclose(group_id);
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H5Fclose(targ_file_id);
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H5Fclose(source_file_id);
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/* The link from the source file to the target file will work as long as
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* the target file can be found. If the target file is moved, renamed,
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* or deleted in the filesystem, HDF5 won't be able to find it and the
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* external link will "dangle."
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*/
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}
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/* External link prefix example
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*
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* Uses a group access property list to set a "prefix" for the filenames
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* accessed through an external link.
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*
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* Group access property lists inherit from link access property lists;
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* the external link prefix property is actually a property of LAPLs.
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*
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* This example requires a "red" directory and a "blue" directory to exist
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* where it is run (so to run this example on Unix, first mkdir red and mkdir
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* blue).
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*/
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static void extlink_prefix_example(void)
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{
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hid_t source_file_id, red_file_id, blue_file_id;
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hid_t group_id, group2_id;
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hid_t gapl_id;
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/* Create three files, a source and two targets. The targets will have
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* the same name, but one will be located in the red directory and one will
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* be located in the blue directory */
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source_file_id = H5Fcreate(PREFIX_SOURCE_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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red_file_id = H5Fcreate("red/prefix_target.h5", H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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blue_file_id = H5Fcreate("blue/prefix_target.h5", H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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/* This test needs a red and a blue directory in the filesystem. If they're not present,
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* trying to create the files above will fail.
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*/
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if(red_file_id < 0 || blue_file_id < 0)
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printf("This test requires directories named 'red' and 'blue' to exist. Did you forget to create them?\n");
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/* Create an external link in the source file pointing to the root group of
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* a file named prefix_target.h5. This file doesn't exist in the current
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* directory, but the files in the red and blue directories both have this
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* name.
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*/
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H5Lcreate_external("prefix_target.h5", "/", source_file_id, "ext_link", H5P_DEFAULT, H5P_DEFAULT);
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/* If we tried to traverse the external link now, we would fail (since the
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* file it points to doesn't exist). Instead, we'll create a group access
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* property list that will provide a prefix path to the external link.
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* Group access property lists inherit the properties of link access
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* property lists.
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*/
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gapl_id = H5Pcreate(H5P_GROUP_ACCESS);
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H5Pset_elink_prefix(gapl_id, "red/");
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/* Now if we traverse the external link, HDF5 will look for an external
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* file named red/prefix_target.h5, which exists.
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* To pass the group access property list, we need to use H5Gopen2.
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*/
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group_id = H5Gopen2(source_file_id, "ext_link", gapl_id);
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/* Now we can use the open group ID to create a new group inside the
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* "red" file.
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*/
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group2_id = H5Gcreate2(group_id, "pink", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
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/* Close both groups. */
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H5Gclose(group2_id);
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H5Gclose(group_id);
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/* If we change the prefix, the same external link can find a file in the blue
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* directory.
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*/
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H5Pset_elink_prefix(gapl_id, "blue/");
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group_id = H5Gopen2(source_file_id, "ext_link", gapl_id);
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group2_id = H5Gcreate2(group_id, "sky blue", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
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/* Close both groups. */
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H5Gclose(group2_id);
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H5Gclose(group_id);
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/* Each file has had a group created inside it using the same external link. */
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group_id = H5Gopen2(red_file_id, "pink", H5P_DEFAULT);
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group2_id = H5Gopen2(blue_file_id, "sky blue", H5P_DEFAULT);
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/* Clean up our open IDs */
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H5Gclose(group2_id);
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H5Gclose(group_id);
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H5Pclose(gapl_id);
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H5Fclose(blue_file_id);
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H5Fclose(red_file_id);
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H5Fclose(source_file_id);
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/* User-defined links can expand on the ability to pass in parameters
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* using an access property list; for instance, a user-defined link
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* might function like an external link but allow the full filename to be
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* passed in through the access property list.
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*/
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}
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/* Soft Link example
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*
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* Create a new class of user-defined links that behave like HDF5's built-in
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* soft links.
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*
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* This isn't very useful by itself (HDF5's soft links already do the same
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* thing), but it can serve as an example for how to reference objects by
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* name.
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*/
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/* We need to define the callback function that the soft link will use.
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* It is defined after the example below.
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* To keep the example simple, these links don't have a query callback.
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* In general, link classes should always be query-able.
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* We might also have wanted to supply a creation callback that checks
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* that a path was supplied in the udata.
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*/
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static hid_t UD_soft_traverse(const char *link_name, hid_t cur_group,
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const void *udata, size_t udata_size, hid_t lapl_id);
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static void soft_link_example(void)
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{
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hid_t file_id;
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hid_t group_id;
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/* Define the link class that we'll use to register "user-defined soft
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* links" using the callbacks we defined above.
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* A link class can have NULL for any callback except its traverse
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* callback.
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*/
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const H5L_class_t UD_soft_class[1] = {{
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H5L_LINK_CLASS_T_VERS, /* Version number for this struct.
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* This field is always H5L_LINK_CLASS_T_VERS */
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(H5L_type_t)UD_SOFT_CLASS, /* Link class id number. This can be any
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* value between H5L_TYPE_UD_MIN (64) and
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* H5L_TYPE_MAX (255). It should be a
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* value that isn't already being used by
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* another kind of link. We'll use 65. */
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"UD_soft_link", /* Link class name for debugging */
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NULL, /* Creation callback */
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NULL, /* Move callback */
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NULL, /* Copy callback */
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UD_soft_traverse, /* The actual traversal function */
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NULL, /* Deletion callback */
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NULL /* Query callback */
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}};
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/* First, create a file and an object within the file for the link to
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* point to.
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*/
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file_id = H5Fcreate(SOFT_LINK_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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group_id = H5Gcreate2(file_id, TARGET_GROUP, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
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H5Gclose(group_id);
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/* This is how we create a normal soft link to the group.
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*/
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H5Lcreate_soft(TARGET_GROUP, file_id, SOFT_LINK_NAME, H5P_DEFAULT, H5P_DEFAULT);
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/* To do the same thing using a user-defined link, we first have to
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* register the link class we defined.
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*/
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H5Lregister(UD_soft_class);
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/* Now create a user-defined link. We give it the path to the group
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* as its udata.1
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*/
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H5Lcreate_ud(file_id, UD_SOFT_LINK_NAME, (H5L_type_t)UD_SOFT_CLASS, TARGET_GROUP,
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strlen(TARGET_GROUP) + 1, H5P_DEFAULT, H5P_DEFAULT);
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/* We can access the group through the UD soft link like we would through
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* a normal soft link. This link will still dangle if the object's
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* original name is changed or unlinked.
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*/
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group_id = H5Gopen2(file_id, UD_SOFT_LINK_NAME, H5P_DEFAULT);
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/* The group is now open normally. Don't forget to close it! */
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H5Gclose(group_id);
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H5Fclose(file_id);
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}
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/* UD_soft_traverse
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* The actual traversal function simply needs to open the correct object by
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* name and return its ID.
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*/
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static hid_t UD_soft_traverse(const char *link_name, hid_t cur_group,
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const void *udata, size_t udata_size, hid_t lapl_id)
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{
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const char *target = (const char *) udata;
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hid_t ret_value;
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/* Pass the udata straight through to HDF5. If it's invalid, let HDF5
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* return an error.
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*/
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ret_value = H5Oopen(cur_group, target, lapl_id);
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return ret_value;
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}
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/* Hard Link example
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*
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* Create a new class of user-defined links that behave like HDF5's built-in
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* hard links.
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*
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* This isn't very useful by itself (HDF5's hard links already do the same
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* thing), but it can serve as an example for how to reference objects by
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* address.
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*/
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/* We need to define the callback functions that the hard link will use.
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* These are defined after the example below.
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* To keep the example simple, these links don't have a query callback.
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* Generally, real link classes should always be query-able.
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*/
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static herr_t UD_hard_create(const char *link_name, hid_t loc_group,
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const void *udata, size_t udata_size, hid_t lcpl_id);
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static herr_t UD_hard_delete(const char *link_name, hid_t loc_group,
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const void *udata, size_t udata_size);
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static hid_t UD_hard_traverse(const char *link_name, hid_t cur_group,
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const void *udata, size_t udata_size, hid_t lapl_id);
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static void hard_link_example(void)
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{
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hid_t file_id;
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hid_t group_id;
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H5L_info_t li;
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/* Define the link class that we'll use to register "user-defined hard
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* links" using the callbacks we defined above.
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* A link class can have NULL for any callback except its traverse
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* callback.
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*/
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const H5L_class_t UD_hard_class[1] = {{
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H5L_LINK_CLASS_T_VERS, /* Version number for this struct.
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* This field is always H5L_LINK_CLASS_T_VERS */
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(H5L_type_t)UD_HARD_CLASS, /* Link class id number. This can be any
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* value between H5L_TYPE_UD_MIN (64) and
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* H5L_TYPE_MAX (255). It should be a
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* value that isn't already being used by
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* another kind of link. We'll use 66. */
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"UD_hard_link", /* Link class name for debugging */
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UD_hard_create, /* Creation callback */
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NULL, /* Move callback */
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NULL, /* Copy callback */
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UD_hard_traverse, /* The actual traversal function */
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UD_hard_delete, /* Deletion callback */
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NULL /* Query callback */
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}};
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/* First, create a file and an object within the file for the link to
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* point to.
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*/
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file_id = H5Fcreate(HARD_LINK_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
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group_id = H5Gcreate2(file_id, TARGET_GROUP, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
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H5Gclose(group_id);
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/* This is how we create a normal hard link to the group. This
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* creates a second "name" for the group.
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*/
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H5Lcreate_hard(file_id, TARGET_GROUP, file_id, HARD_LINK_NAME, H5P_DEFAULT, H5P_DEFAULT);
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/* To do the same thing using a user-defined link, we first have to
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* register the link class we defined.
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*/
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H5Lregister(UD_hard_class);
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/* Since hard links link by object address, we'll need to retrieve
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* the target group's address. We do this by calling H5Lget_info
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* on a hard link to the object.
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*/
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H5Lget_info(file_id, TARGET_GROUP, &li, H5P_DEFAULT);
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/* Now create a user-defined link. We give it the group's address
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* as its udata.
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*/
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H5Lcreate_ud(file_id, UD_HARD_LINK_NAME, (H5L_type_t)UD_HARD_CLASS, &(li.u.address),
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sizeof(li.u.address), H5P_DEFAULT, H5P_DEFAULT);
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/* The UD hard link has now incremented the group's reference count
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* like a normal hard link would. This means that we can unlink the
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* other two links to that group and it won't be deleted until the
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* UD hard link is deleted.
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*/
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H5Ldelete(file_id, TARGET_GROUP, H5P_DEFAULT);
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H5Ldelete(file_id, HARD_LINK_NAME, H5P_DEFAULT);
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/* The group is still accessible through the UD hard link. If this were
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* a soft link instead, the object would have been deleted when the last
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* hard link to it was unlinked. */
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group_id = H5Gopen2(file_id, UD_HARD_LINK_NAME, H5P_DEFAULT);
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/* The group is now open normally. Don't forget to close it! */
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H5Gclose(group_id);
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/* Removing the user-defined hard link will delete the group. */
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H5Ldelete(file_id, UD_HARD_LINK_NAME, H5P_DEFAULT);
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H5Fclose(file_id);
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}
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/* Callbacks for User-defined hard links. */
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/* UD_hard_create
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* The most important thing this callback does is to increment the reference
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* count on the target object. Without this step, the object could be
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* deleted while this link still pointed to it, resulting in possible data
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* corruption!
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* The create callback also checks the arguments used to create this link.
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* If this function returns a negative value, the call to H5Lcreate_ud()
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* will also return failure and the link will not be created.
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*/
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static herr_t UD_hard_create(const char *link_name, hid_t loc_group,
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const void *udata, size_t udata_size, hid_t lcpl_id)
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{
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haddr_t addr;
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hid_t target_obj = -1;
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herr_t ret_value = 0;
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/* Make sure that the address passed in looks valid */
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if(udata_size != sizeof(haddr_t))
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{
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ret_value = -1;
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goto done;
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}
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addr = *((const haddr_t *) udata);
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/* Open the object this link points to so that we can increment
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* its reference count. This also ensures that the address passed
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* in points to a real object (although this check is not perfect!) */
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target_obj= H5Oopen_by_addr(loc_group, addr);
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if(target_obj < 0)
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{
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ret_value = -1;
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goto done;
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}
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/* Increment the reference count of the target object */
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if(H5Oincr_refcount(target_obj) < 0)
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{
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ret_value = -1;
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goto done;
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}
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done:
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/* Close the target object if we opened it */
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if(target_obj >= 0)
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H5Oclose(target_obj);
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return ret_value;
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}
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|
||
/* UD_hard_delete
|
||
* Since the creation function increments the object's reference count, it's
|
||
* important to decrement it again when the link is deleted.
|
||
*/
|
||
static herr_t UD_hard_delete(const char *link_name, hid_t loc_group,
|
||
const void *udata, size_t udata_size)
|
||
{
|
||
haddr_t addr;
|
||
hid_t target_obj = -1;
|
||
herr_t ret_value = 0;
|
||
|
||
/* Sanity check; we have already verified the udata's size in the creation
|
||
* callback.
|
||
*/
|
||
if(udata_size != sizeof(haddr_t))
|
||
{
|
||
ret_value = -1;
|
||
goto done;
|
||
}
|
||
|
||
addr = *((const haddr_t *) udata);
|
||
|
||
/* Open the object this link points to */
|
||
target_obj= H5Oopen_by_addr(loc_group, addr);
|
||
if(target_obj < 0)
|
||
{
|
||
ret_value = -1;
|
||
goto done;
|
||
}
|
||
|
||
/* Decrement the reference count of the target object */
|
||
if(H5Odecr_refcount(target_obj) < 0)
|
||
{
|
||
ret_value = -1;
|
||
goto done;
|
||
}
|
||
|
||
done:
|
||
/* Close the target object if we opened it */
|
||
if(target_obj >= 0)
|
||
H5Oclose(target_obj);
|
||
return ret_value;
|
||
}
|
||
|
||
/* UD_hard_traverse
|
||
* The actual traversal function simply needs to open the correct object and
|
||
* return its ID.
|
||
*/
|
||
static hid_t UD_hard_traverse(const char *link_name, hid_t cur_group,
|
||
const void *udata, size_t udata_size, hid_t lapl_id)
|
||
{
|
||
haddr_t addr;
|
||
hid_t ret_value = -1;
|
||
|
||
/* Sanity check; we have already verified the udata's size in the creation
|
||
* callback.
|
||
*/
|
||
if(udata_size != sizeof(haddr_t))
|
||
return -1;
|
||
|
||
addr = *((const haddr_t *) udata);
|
||
|
||
/* Open the object by address. If H5Oopen_by_addr fails, ret_value will
|
||
* be negative to indicate that the traversal function failed.
|
||
*/
|
||
ret_value = H5Oopen_by_addr(cur_group, addr);
|
||
|
||
return ret_value;
|
||
}
|
||
|
||
|
||
|
||
/* Plist example
|
||
*
|
||
* Create a new class of user-defined links that open objects within a file
|
||
* based on a value passed in through a link access property list.
|
||
*
|
||
* Group, dataset, and datatype access property lists all inherit from link
|
||
* access property lists, so they can be used instead of LAPLs.
|
||
*/
|
||
|
||
/* We need to define the callback functions that this link type will use.
|
||
* These are defined after the example below.
|
||
* These links have no udata, so they don't need a query function.
|
||
*/
|
||
static hid_t UD_plist_traverse(const char *link_name, hid_t cur_group,
|
||
const void *udata, size_t udata_size, hid_t lapl_id);
|
||
|
||
static void plist_link_example(void)
|
||
{
|
||
hid_t file_id;
|
||
hid_t group_id, group2_id;
|
||
hid_t gapl_id;
|
||
char *path = NULL;
|
||
|
||
/* Define the link class that we'll use to register "plist
|
||
* links" using the callback we defined above.
|
||
* A link class can have NULL for any callback except its traverse
|
||
* callback.
|
||
*/
|
||
const H5L_class_t UD_plist_class[1] = {{
|
||
H5L_LINK_CLASS_T_VERS, /* Version number for this struct.
|
||
* This field is always H5L_LINK_CLASS_T_VERS */
|
||
(H5L_type_t)UD_PLIST_CLASS, /* Link class id number. This can be any
|
||
* value between H5L_TYPE_UD_MIN (64) and
|
||
* H5L_TYPE_MAX (255). It should be a
|
||
* value that isn't already being used by
|
||
* another kind of link. We'll use 67. */
|
||
"UD_plist_link", /* Link class name for debugging */
|
||
NULL, /* Creation callback */
|
||
NULL, /* Move callback */
|
||
NULL, /* Copy callback */
|
||
UD_plist_traverse, /* The actual traversal function */
|
||
NULL, /* Deletion callback */
|
||
NULL /* Query callback */
|
||
}};
|
||
|
||
|
||
/* First, create a file and two objects within the file for the link to
|
||
* point to.
|
||
*/
|
||
file_id = H5Fcreate(HARD_LINK_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
|
||
group_id = H5Gcreate2(file_id, "group_1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
|
||
H5Gclose(group_id);
|
||
group_id = H5Gcreate2(file_id, "group_1/group_2", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
|
||
H5Gclose(group_id);
|
||
|
||
/* Register "plist links" and create one. It has no udata at all. */
|
||
H5Lregister(UD_plist_class);
|
||
H5Lcreate_ud(file_id, "plist_link", (H5L_type_t)UD_PLIST_CLASS, NULL, 0,
|
||
H5P_DEFAULT, H5P_DEFAULT);
|
||
|
||
/* Create a group access property list to pass in the target for the
|
||
* plist link.
|
||
*/
|
||
gapl_id = H5Pcreate(H5P_GROUP_ACCESS);
|
||
|
||
/* There is no HDF5 API for setting the property that controls these
|
||
* links, so we have to add the property manually
|
||
*/
|
||
H5Pinsert2(gapl_id, PLIST_LINK_PROP, sizeof(const char *), &(path), NULL, NULL, NULL, NULL, NULL, NULL);
|
||
|
||
/* Set the property to point to the first group. */
|
||
path = "group_1";
|
||
H5Pset(gapl_id, PLIST_LINK_PROP, &path);
|
||
|
||
/* Open the first group through the plist link using the GAPL we just
|
||
* created */
|
||
group_id = H5Gopen2(file_id, "plist_link", gapl_id);
|
||
|
||
/* If we change the value set on the property list, it will change where
|
||
* the plist link points.
|
||
*/
|
||
path = "group_1/group_2";
|
||
H5Pset(gapl_id, PLIST_LINK_PROP, &path);
|
||
group2_id = H5Gopen2(file_id, "plist_link", gapl_id);
|
||
|
||
/* group_id points to group_1 and group2_id points to group_2, both opened
|
||
* through the same link.
|
||
* Using more than one of this type of link could quickly become confusing,
|
||
* since they will all use the same property list; however, there is
|
||
* nothing to prevent the links from changing the property list in their
|
||
* traverse callbacks.
|
||
*/
|
||
|
||
/* Clean up */
|
||
H5Pclose(gapl_id);
|
||
H5Gclose(group_id);
|
||
H5Gclose(group2_id);
|
||
H5Fclose(file_id);
|
||
}
|
||
|
||
/* Traversal callback for User-defined plist links. */
|
||
/* UD_plist_traverse
|
||
* Open a path passed in through the property list.
|
||
*/
|
||
static hid_t UD_plist_traverse(const char *link_name, hid_t cur_group,
|
||
const void *udata, size_t udata_size, hid_t lapl_id)
|
||
{
|
||
char * path;
|
||
hid_t ret_value = -1;
|
||
|
||
/* If the link property isn't set or can't be found, traversal fails. */
|
||
if(H5Pexist(lapl_id, PLIST_LINK_PROP) < 0)
|
||
goto error;
|
||
|
||
if(H5Pget(lapl_id, PLIST_LINK_PROP, &path) < 0)
|
||
goto error;
|
||
|
||
/* Open the object by address. If H5Oopen_by_addr fails, ret_value will
|
||
* be negative to indicate that the traversal function failed.
|
||
*/
|
||
ret_value = H5Oopen(cur_group, path, lapl_id);
|
||
|
||
return ret_value;
|
||
|
||
error:
|
||
return -1;
|
||
}
|
||
|
||
|
||
|
||
/* Main function
|
||
*
|
||
* Invokes the example functions.
|
||
*/
|
||
int
|
||
main(void)
|
||
{
|
||
printf("Testing basic external links.\n");
|
||
extlink_example();
|
||
|
||
printf("Testing external link prefixes.\n");
|
||
extlink_prefix_example();
|
||
|
||
printf("Testing user-defined soft links.\n");
|
||
soft_link_example();
|
||
|
||
printf("Testing user-defined hard links.\n");
|
||
hard_link_example();
|
||
|
||
printf("Testing user-defined property list links.\n");
|
||
plist_link_example();
|
||
|
||
return 0;
|
||
}
|
||
|
||
|