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Diffstat (limited to 'doxygen/examples/H5DO_examples.c')
| -rw-r--r-- | doxygen/examples/H5DO_examples.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/doxygen/examples/H5DO_examples.c b/doxygen/examples/H5DO_examples.c new file mode 100644 index 0000000..7a33c6b --- /dev/null +++ b/doxygen/examples/H5DO_examples.c @@ -0,0 +1,220 @@ +/* -*- c-file-style: "stroustrup" -*- */ + +//! <!-- [H5DOwrite] --> + +#include <zlib.h> +#include <math.h> +#define DEFLATE_SIZE_ADJUST(s) (ceil(((double)(s)) * 1.001) + 12) + : + : +size_t buf_size = CHUNK_NX*CHUNK_NY*sizeof(int); + const Bytef *z_src = (const Bytef *)(direct_buf); + Bytef * z_dst; /* Destination buffer */ + uLongf z_dst_nbytes = (uLongf)DEFLATE_SIZE_ADJUST(buf_size); + uLong z_src_nbytes = (uLong)buf_size; + int aggression = 9; /* Compression aggression setting */ + uint32_t filter_mask = 0; + size_t buf_size = CHUNK_NX * CHUNK_NY * sizeof(int); + + /* Create the data space */ + if ((dataspace = H5Screate_simple(RANK, dims, maxdims)) < 0) + goto error; + + /* Create a new file */ + if ((file = H5Fcreate(FILE_NAME5, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) + goto error; + + /* Modify dataset creation properties, i.e. enable chunking and compression */ + if ((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0) + goto error; + + if ((status = H5Pset_chunk(cparms, RANK, chunk_dims)) < 0) + goto error; + + if ((status = H5Pset_deflate(cparms, aggression)) < 0) + goto error; + + /* Create a new dataset within the file using cparms creation properties */ + if ((dset_id = H5Dcreate2(file, DATASETNAME, H5T_NATIVE_INT, dataspace, H5P_DEFAULT, cparms, + H5P_DEFAULT)) < 0) + goto error; + + /* Initialize data for one chunk */ + for (i = n = 0; i < CHUNK_NX; i++) + for (j = 0; j < CHUNK_NY; j++) + direct_buf[i][j] = n++; + + /* Allocate output (compressed) buffer */ + outbuf = malloc(z_dst_nbytes); + z_dst = (Bytef *)outbuf; + + /* Perform compression from the source to the destination buffer */ + ret = compress2(z_dst, &z_dst_nbytes, z_src, z_src_nbytes, aggression); + + /* Check for various zlib errors */ + if (Z_BUF_ERROR == ret) { + fprintf(stderr, "overflow"); + goto error; + } + else if (Z_MEM_ERROR == ret) { + fprintf(stderr, "deflate memory error"); + goto error; + } + else if (Z_OK != ret) { + fprintf(stderr, "other deflate error"); + goto error; + } + + /* Write the compressed chunk data repeatedly to cover all the + * * chunks in the dataset, using the direct write function. */ + for (i = 0; i < NX / CHUNK_NX; i++) { + for (j = 0; j < NY / CHUNK_NY; j++) { + status = + H5DOwrite_chunk(dset_id, H5P_DEFAULT, filter_mask, offset, z_dst_nbytes, outbuf); + offset[1] += CHUNK_NY; + } + offset[0] += CHUNK_NX; + offset[1] = 0; + } + + /* Overwrite the first chunk with uncompressed data. Set the filter mask to + * * indicate the compression filter is skipped */ + filter_mask = 0x00000001; + offset[0] = offset[1] = 0; + if (H5DOwrite_chunk(dset_id, H5P_DEFAULT, filter_mask, offset, buf_size, direct_buf) < 0) + goto error; + + /* Read the entire dataset back for data verification converting ints to longs */ + if (H5Dread(dataset, H5T_NATIVE_LONG, H5S_ALL, H5S_ALL, H5P_DEFAULT, outbuf_long) < 0) + goto error; + + /* Data verification here */ + : + : + + //! <!-- [H5DOwrite] --> + + //! <!-- [H5DOread] --> + +#include <zlib.h> +#include <math.h> +#define DEFLATE_SIZE_ADJUST(s) (ceil(((double)(s)) * 1.001) + 12) + : + : +size_t buf_size = CHUNK_NX*CHUNK_NY*sizeof(int); + const Bytef *z_src = (const Bytef *)(direct_buf); + Bytef * z_dst; /* Destination buffer */ + uLongf z_dst_nbytes = (uLongf)DEFLATE_SIZE_ADJUST(buf_size); + uLong z_src_nbytes = (uLong)buf_size; + int aggression = 9; /* Compression aggression setting */ + uint32_t filter_mask = 0; + size_t buf_size = CHUNK_NX * CHUNK_NY * sizeof(int); + /* For H5DOread_chunk() */ + void * readbuf = NULL; /* Buffer for reading data */ + const Bytef *pt_readbuf; /* Point to the buffer for data read */ + hsize_t read_chunk_nbytes; /* Size of chunk on disk */ + int read_dst_buf[CHUNK_NX][CHUNK_NY]; /* Buffer to hold un-compressed data */ + + /* Create the data space */ + if ((dataspace = H5Screate_simple(RANK, dims, maxdims)) < 0) + goto error; + + /* Create a new file */ + if ((file = H5Fcreate(FILE_NAME5, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) + goto error; + + /* Modify dataset creation properties, i.e. enable chunking and compression */ + if ((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0) + goto error; + + if ((status = H5Pset_chunk(cparms, RANK, chunk_dims)) < 0) + goto error; + + if ((status = H5Pset_deflate(cparms, aggression)) < 0) + goto error; + + /* Create a new dataset within the file using cparms creation properties */ + if ((dset_id = H5Dcreate2(file, DATASETNAME, H5T_NATIVE_INT, dataspace, H5P_DEFAULT, cparms, + H5P_DEFAULT)) < 0) + goto error; + + /* Initialize data for one chunk */ + for (i = n = 0; i < CHUNK_NX; i++) + for (j = 0; j < CHUNK_NY; j++) + direct_buf[i][j] = n++; + + /* Allocate output (compressed) buffer */ + outbuf = malloc(z_dst_nbytes); + z_dst = (Bytef *)outbuf; + + /* Perform compression from the source to the destination buffer */ + ret = compress2(z_dst, &z_dst_nbytes, z_src, z_src_nbytes, aggression); + + /* Check for various zlib errors */ + if (Z_BUF_ERROR == ret) { + fprintf(stderr, "overflow"); + goto error; + } + else if (Z_MEM_ERROR == ret) { + fprintf(stderr, "deflate memory error"); + goto error; + } + else if (Z_OK != ret) { + fprintf(stderr, "other deflate error"); + goto error; + } + + /* Write the compressed chunk data repeatedly to cover all the + * * chunks in the dataset, using the direct write function. */ + for (i = 0; i < NX / CHUNK_NX; i++) { + for (j = 0; j < NY / CHUNK_NY; j++) { + status = H5DOwrite_chunk(dset_id, H5P_DEFAULT, filter_mask, offset, z_dst_nbytes, outbuf); + offset[1] += CHUNK_NY; + } + offset[0] += CHUNK_NX; + offset[1] = 0; + } + + if (H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0) + goto error; + + if (H5Dclose(dataset) < 0) + goto error; + + if ((dataset = H5Dopen2(file, DATASETNAME1, H5P_DEFAULT)) < 0) + goto error; + + offset[0] = CHUNK_NX; + offset[1] = CHUNK_NY; + + /* Get the size of the compressed chunk */ + ret = H5Dget_chunk_storage_size(dataset, offset, &read_chunk_nbytes); + + readbuf = HDmalloc(read_chunk_nbytes); + pt_readbuf = (const Bytef *)readbuf; + + /* Use H5DOread_chunk() to read the chunk back */ + if ((status = H5DOread_chunk(dataset, H5P_DEFAULT, offset, &read_filter_mask, readbuf)) < 0) + goto error; + + ret = + uncompress((Bytef *)read_dst_buf, (uLongf *)&buf_size, pt_readbuf, (uLong)read_chunk_nbytes); + + /* Check for various zlib errors */ + if (Z_BUF_ERROR == ret) { + fprintf(stderr, "error: not enough room in output buffer"); + goto error; + } + else if (Z_MEM_ERROR == ret) { + fprintf(stderr, "error: not enough memory"); + goto error; + } + else if (Z_OK != ret) { + fprintf(stderr, "error: corrupted input data"); + goto error; + } + + /* Data verification here */ + : + : +//! <!-- [H5DOread] --> |