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Diffstat (limited to 'src/H5FDmulti.h')
| -rw-r--r-- | src/H5FDmulti.h | 219 |
1 files changed, 218 insertions, 1 deletions
diff --git a/src/H5FDmulti.h b/src/H5FDmulti.h index 9e04d8d..62cc9c8 100644 --- a/src/H5FDmulti.h +++ b/src/H5FDmulti.h @@ -25,11 +25,228 @@ #ifdef __cplusplus extern "C" { #endif -H5_DLL hid_t H5FD_multi_init(void); +H5_DLL hid_t H5FD_multi_init(void); + +/** + * \ingroup FAPL + * + * \brief Sets up use of the multi-file driver + * + * \fapl_id + * \param[in] memb_map Maps memory usage types to other memory usage types + * \param[in] memb_fapl Property list for each memory usage type + * \param[in] memb_name Name generator for names of member files + * \param[in] memb_addr The offsets within the virtual address space, from 0 + * (zero) to #HADDR_MAX, at which each type of data storage begins + * \param[in] relax Allows read-only access to incomplete file sets when \c TRUE + * \returns \herr_t + * + * \details H5Pset_fapl_multi() sets the file access property list \p fapl_id to + * use the multi-file driver. + * + * The multi-file driver enables different types of HDF5 data and + * metadata to be written to separate files. These files are viewed by + * the HDF5 library and the application as a single virtual HDF5 file + * with a single HDF5 file address space. The types of data that can be + * broken out into separate files include raw data, the superblock, + * B-tree data, global heap data, local heap data, and object + * headers. At the programmer's discretion, two or more types of data + * can be written to the same file while other types of data are + * written to separate files. + * + * The array \p memb_map maps memory usage types to other memory usage + * types and is the mechanism that allows the caller to specify how + * many files are created. The array contains #H5FD_MEM_NTYPES entries, + * which are either the value #H5FD_MEM_DEFAULT or a memory usage + * type. The number of unique values determines the number of files + * that are opened. + * + * The array \p memb_fapl contains a property list for each memory + * usage type that will be associated with a file. + * + * The array \p memb_name should be a name generator (a + * \Code{printf}-style format with a \Code{%s} which will be replaced + * with the name passed to H5FDopen(), usually from H5Fcreate() or + * H5Fopen()). + * + * The array \p memb_addr specifies the offsets within the virtual + * address space, from 0 (zero) to #HADDR_MAX, at which each type of + * data storage begins. + * + * If \p relax is set to 1 (TRUE), then opening an existing file for + * read-only access will not fail if some file members are + * missing. This allows a file to be accessed in a limited sense if + * just the meta data is available. + * + * Default values for each of the optional arguments are as follows: + * <table> + * <tr> + * <td>\p memb_map</td> + * <td>The default member map contains the value #H5FD_MEM_DEFAULT for each element.</td> + * </tr> + * <tr> + * <td> + * \p memb_fapl + * </td> + * <td> + * The default value is #H5P_DEFAULT for each element. + * </td> + * </tr> + * <tr> + * <td> + * \p memb_name + * </td> + * <td> + * The default string is \Code{%s-X.h5} where \c X is one of the following letters: + * - \c s for #H5FD_MEM_SUPER + * - \c b for #H5FD_MEM_BTREE + * - \c r for #H5FD_MEM_DRAW + * - \c g for #H5FD_MEM_GHEAP + * - \c l for #H5FD_MEM_LHEAP + * - \c o for #H5FD_MEM_OHDR + * </td> + * </tr> + * <tr> + * <td> + * \p memb_addr + * </td> + * <td> + * The default setting is that the address space is equally divided + * among all of the elements: + * - #H5FD_MEM_SUPER \Code{-> 0 * (HADDR_MAX/6)} + * - #H5FD_MEM_BTREE \Code{-> 1 * (HADDR_MAX/6)} + * - #H5FD_MEM_DRAW \Code{-> 2 * (HADDR_MAX/6)} + * - #H5FD_MEM_GHEAP \Code{-> 3 * (HADDR_MAX/6)} + * - #H5FD_MEM_LHEAP \Code{-> 4 * (HADDR_MAX/6)} + * - #H5FD_MEM_OHDR \Code{-> 5 * (HADDR_MAX/6)} + * </td> + * </tr> + * </table> + * + * \par Example: + * The following code sample sets up a multi-file access property list that + * partitions data into meta and raw files, each being one-half of the address:\n + * \code + * H5FD_mem_t mt, memb_map[H5FD_MEM_NTYPES]; + * hid_t memb_fapl[H5FD_MEM_NTYPES]; + * const char *memb[H5FD_MEM_NTYPES]; + * haddr_t memb_addr[H5FD_MEM_NTYPES]; + * + * // The mapping... + * for (mt=0; mt<H5FD_MEM_NTYPES; mt++) { + * memb_map[mt] = H5FD_MEM_SUPER; + * } + * memb_map[H5FD_MEM_DRAW] = H5FD_MEM_DRAW; + * + * // Member information + * memb_fapl[H5FD_MEM_SUPER] = H5P_DEFAULT; + * memb_name[H5FD_MEM_SUPER] = "%s.meta"; + * memb_addr[H5FD_MEM_SUPER] = 0; + * + * memb_fapl[H5FD_MEM_DRAW] = H5P_DEFAULT; + * memb_name[H5FD_MEM_DRAW] = "%s.raw"; + * memb_addr[H5FD_MEM_DRAW] = HADDR_MAX/2; + * + * hid_t fapl = H5Pcreate(H5P_FILE_ACCESS); + * H5Pset_fapl_multi(fapl, memb_map, memb_fapl, + * memb_name, memb_addr, TRUE); + * \endcode + * + * \version 1.6.3 \p memb_name parameter type changed to \Code{const char* const*}. + * \since 1.4.0 + */ H5_DLL herr_t H5Pset_fapl_multi(hid_t fapl_id, const H5FD_mem_t *memb_map, const hid_t *memb_fapl, const char *const *memb_name, const haddr_t *memb_addr, hbool_t relax); + +/** + * \ingroup FAPL + * + * \brief Returns information about the multi-file access property list + * + * \fapl_id + * \param[out] memb_map Maps memory usage types to other memory usage types + * \param[out] memb_fapl Property list for each memory usage type + * \param[out] memb_name Name generator for names of member files + * \param[out] memb_addr The offsets within the virtual address space, from 0 + * (zero) to #HADDR_MAX, at which each type of data storage begins + * \param[out] relax Allows read-only access to incomplete file sets when \c TRUE + * \returns \herr_t + * + * \details H5Pget_fapl_multi() returns information about the multi-file access + * property list. + * + * \since 1.4.0 + * + */ H5_DLL herr_t H5Pget_fapl_multi(hid_t fapl_id, H5FD_mem_t *memb_map /*out*/, hid_t *memb_fapl /*out*/, char **memb_name /*out*/, haddr_t *memb_addr /*out*/, hbool_t *relax /*out*/); + +/** + * \ingroup FAPL + * + * \brief Emulates the old split file driver + * + * \fapl_id{fapl} + * \param[in] meta_ext Metadata filename extension + * \param[in] meta_plist_id File access property list identifier for the metadata file + * \param[in] raw_ext Raw data filename extension + * \param[in] raw_plist_id + * \returns \herr_t + * + * \details H5Pset_fapl_split() is a compatibility function that enables the + * multi-file driver to emulate the split driver from HDF5 Releases 1.0 + * and 1.2. The split file driver stored metadata and raw data in + * separate files but provided no mechanism for separating types of + * metadata. + * + * \p fapl is a file access property list identifier. + * + * \p meta_ext is the filename extension for the metadata file. The + * extension is appended to the name passed to H5FDopen(), usually from + * H5Fcreate() or H5Fopen(), to form the name of the metadata file. If + * the string \Code{%s} is used in the extension, it works like the + * name generator as in H5Pset_fapl_multi(). + * + * \p meta_plist_id is the file access property list identifier for the + * metadata file. + * + * \p raw_ext is the filename extension for the raw data file. The + * extension is appended to the name passed to H5FDopen(), usually from + * H5Fcreate() or H5Fopen(), to form the name of the raw data file. If + * the string \Code{%s} is used in the extension, it works like the + * name generator as in H5Pset_fapl_multi(). + * + * \p raw_plist_id is the file access property list identifier for the + * raw data file. + * + * If a user wishes to check to see whether this driver is in use, the + * user must call H5Pget_driver() and compare the returned value to the + * string #H5FD_MULTI. A positive match will confirm that the multi + * driver is in use; HDF5 provides no mechanism to determine whether it + * was called as the special case invoked by H5Pset_fapl_split(). + * + * \par Example: + * \code + * // Example 1: Both metadata and rawdata files are in the same + * // directory. Use Station1-m.h5 and Station1-r.h5 as + * // the metadata and rawdata files. + * hid_t fapl, fid; + * fapl = H5Pcreate(H5P_FILE_ACCESS); + * H5Pset_fapl_split(fapl, "-m.h5", H5P_DEFAULT, "-r.h5", H5P_DEFAULT); + * fid=H5Fcreate("Station1",H5F_ACC_TRUNC,H5P_DEFAULT,fapl); + * + * // Example 2: metadata and rawdata files are in different + * // directories. Use PointA-m.h5 and /pfs/PointA-r.h5 as + * // the metadata and rawdata files. + * hid_t fapl, fid; + * fapl = H5Pcreate(H5P_FILE_ACCESS); + * H5Pset_fapl_split(fapl, "-m.h5", H5P_DEFAULT, "/pfs/%s-r.h5", H5P_DEFAULT); + * fid=H5Fcreate("PointA",H5F_ACC_TRUNC,H5P_DEFAULT,fapl); + * \endcode + * + * \since 1.4.0 + * + */ H5_DLL herr_t H5Pset_fapl_split(hid_t fapl, const char *meta_ext, hid_t meta_plist_id, const char *raw_ext, hid_t raw_plist_id); #ifdef __cplusplus |