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authorQuincey Koziol <koziol@hdfgroup.org>2003-04-03 13:52:30 (GMT)
committerQuincey Koziol <koziol@hdfgroup.org>2003-04-03 13:52:30 (GMT)
commit3c77efae1c2b56b80afa30d20536fe344ace7431 (patch)
treeb13812f2ab6b205ba1bc4bde511418df07abfe79
parentdb8ff96dc0e357162f3b2c0b14efc9159e19d162 (diff)
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[svn-r6578] Purpose:
Code cleanup Description: Added lots of comments to existing filters, so they are easier to understand and use as examples for future filters. Cleaned up various bits of code, etc. Solution: Platforms tested: FreeBSD 4.8 (sleipnir) IRIX64 6.5 (modi4) w/parallel Misc. update:
-rw-r--r--src/H5Z.c6
-rw-r--r--src/H5Zdeflate.c77
-rw-r--r--src/H5Zfletcher32.c64
-rw-r--r--src/H5Zshuffle.c22
-rw-r--r--src/Makefile.in2
5 files changed, 103 insertions, 68 deletions
diff --git a/src/H5Z.c b/src/H5Z.c
index 681ed04..cb96be5 100644
--- a/src/H5Z.c
+++ b/src/H5Z.c
@@ -53,9 +53,6 @@ H5Z_init_interface (void)
{
FUNC_ENTER_NOINIT(H5Z_init_interface);
-#ifdef H5_HAVE_FILTER_SZIP
- H5Z_register (H5Z_FILTER_SZIP, "szip", H5Z_filter_szip);
-#endif /* H5_HAVE_FILTER_SZIP */
#ifdef H5_HAVE_FILTER_DEFLATE
H5Z_register (H5Z_FILTER_DEFLATE, "deflate", H5Z_filter_deflate);
#endif /* H5_HAVE_FILTER_DEFLATE */
@@ -65,6 +62,9 @@ H5Z_init_interface (void)
#ifdef H5_HAVE_FILTER_FLETCHER32
H5Z_register (H5Z_FILTER_FLETCHER32, "fletcher32", H5Z_filter_fletcher32);
#endif /* H5_HAVE_FILTER_FLETCHER32 */
+#ifdef H5_HAVE_FILTER_SZIP
+ H5Z_register (H5Z_FILTER_SZIP, "szip", H5Z_filter_szip);
+#endif /* H5_HAVE_FILTER_SZIP */
FUNC_LEAVE_NOAPI(SUCCEED);
}
diff --git a/src/H5Zdeflate.c b/src/H5Zdeflate.c
index d94185f..144c873 100644
--- a/src/H5Zdeflate.c
+++ b/src/H5Zdeflate.c
@@ -16,10 +16,11 @@
* Programmer: Robb Matzke <matzke@llnl.gov>
* Friday, August 27, 1999
*/
-#include "H5private.h"
-#include "H5Eprivate.h"
-#include "H5MMprivate.h"
-#include "H5Zprivate.h"
+
+#include "H5private.h" /* Generic Functions */
+#include "H5Eprivate.h" /* Error handling */
+#include "H5MMprivate.h" /* Memory management */
+#include "H5Zprivate.h" /* Data filters */
#ifdef H5_HAVE_FILTER_DEFLATE
@@ -41,9 +42,8 @@ static int interface_initialize_g = 0;
* Purpose: Implement an I/O filter around the 'deflate' algorithm in
* libz
*
- * Return: Success:
- *
- * Failure:
+ * Return: Success: Size of buffer filtered
+ * Failure: 0
*
* Programmer: Robb Matzke
* Thursday, April 16, 1998
@@ -57,10 +57,9 @@ H5Z_filter_deflate (unsigned flags, size_t cd_nelmts,
const unsigned cd_values[], size_t nbytes,
size_t *buf_size, void **buf)
{
- size_t ret_value = 0;
- void *outbuf = NULL;
- int aggression = 6;
- int status;
+ void *outbuf = NULL; /* Pointer to new buffer */
+ int status; /* Status from zlib operation */
+ size_t ret_value; /* Return value */
FUNC_ENTER_NOAPI(H5Z_filter_deflate, 0);
@@ -68,68 +67,104 @@ H5Z_filter_deflate (unsigned flags, size_t cd_nelmts,
if (cd_nelmts!=1 || cd_values[0]>9)
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid deflate aggression level");
- aggression = cd_values[0];
if (flags & H5Z_FLAG_REVERSE) {
/* Input; uncompress */
- z_stream z_strm;
- size_t nalloc = *buf_size;
+ z_stream z_strm; /* zlib parameters */
+ size_t nalloc = *buf_size; /* Number of bytes for output (compressed) buffer */
+ /* Allocate space for the compressed buffer */
if (NULL==(outbuf = H5MM_malloc(nalloc)))
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "memory allocation failed for deflate uncompression");
+
+ /* Set the uncompression parameters */
HDmemset(&z_strm, 0, sizeof(z_strm));
z_strm.next_in = *buf;
H5_ASSIGN_OVERFLOW(z_strm.avail_in,nbytes,size_t,uInt);
z_strm.next_out = outbuf;
H5_ASSIGN_OVERFLOW(z_strm.avail_out,nalloc,size_t,uInt);
+
+ /* Initialize the uncompression routines */
if (Z_OK!=inflateInit(&z_strm))
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "inflateInit() failed");
+
+ /* Loop to uncompress the buffer */
while (1) {
+ /* Uncompress some data */
status = inflate(&z_strm, Z_SYNC_FLUSH);
+
+ /* Check if we are done uncompressing data */
if (Z_STREAM_END==status)
break; /*done*/
+
+ /* Check for error */
if (Z_OK!=status) {
inflateEnd(&z_strm);
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "inflate() failed");
}
+
+ /* If we're not done and just ran out of buffer space, get more */
if (Z_OK==status && 0==z_strm.avail_out) {
+ /* Allocate a buffer twice as big */
nalloc *= 2;
if (NULL==(outbuf = H5MM_realloc(outbuf, nalloc))) {
inflateEnd(&z_strm);
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "memory allocation failed for deflate uncompression");
}
+
+ /* Update pointers to buffer for next set of uncompressed data */
z_strm.next_out = (unsigned char*)outbuf + z_strm.total_out;
z_strm.avail_out = (uInt)(nalloc - z_strm.total_out);
}
}
+ /* Free the input buffer */
H5MM_xfree(*buf);
+
+ /* Set return values */
*buf = outbuf;
outbuf = NULL;
*buf_size = nalloc;
ret_value = z_strm.total_out;
+
+ /* Finish uncompressing the stream */
inflateEnd(&z_strm);
- } else {
+ }
+ else {
/*
* Output; compress but fail if the result would be larger than the
* input. The library doesn't provide in-place compression, so we
* must allocate a separate buffer for the result.
*/
- const Bytef *z_src = (const Bytef*)(*buf);
- Bytef *z_dst; /*destination buffer */
- uLongf z_dst_nbytes = (uLongf)H5Z_DEFLATE_SIZE_ADJUST(nbytes);
- uLong z_src_nbytes = (uLong)nbytes;
+ const Bytef *z_src = (const Bytef*)(*buf);
+ Bytef *z_dst; /*destination buffer */
+ uLongf z_dst_nbytes = (uLongf)H5Z_DEFLATE_SIZE_ADJUST(nbytes);
+ uLong z_src_nbytes = (uLong)nbytes;
+ int aggression; /* Compression aggression setting */
+ /* Set the compression aggression level */
+ aggression = cd_values[0];
+
+ /* Allocate output (compressed) buffer */
if (NULL==(z_dst=outbuf=H5MM_malloc(z_dst_nbytes)))
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "unable to allocate deflate destination buffer");
+
+ /* Perform compression from the source to the destination buffer */
status = compress2 (z_dst, &z_dst_nbytes, z_src, z_src_nbytes, aggression);
+
+ /* Check for various zlib errors */
if (Z_BUF_ERROR==status) {
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "overflow");
} else if (Z_MEM_ERROR==status) {
HGOTO_ERROR (H5E_PLINE, H5E_CANTINIT, 0, "deflate memory error");
} else if (Z_OK!=status) {
HGOTO_ERROR (H5E_PLINE, H5E_CANTINIT, 0, "other deflate error");
- } else {
+ }
+ /* Successfully uncompressed the buffer */
+ else {
+ /* Free the input buffer */
H5MM_xfree(*buf);
+
+ /* Set return values */
*buf = outbuf;
outbuf = NULL;
*buf_size = nbytes;
@@ -142,5 +177,5 @@ done:
H5MM_xfree(outbuf);
FUNC_LEAVE_NOAPI(ret_value);
}
-
#endif /* H5_HAVE_FILTER_DEFLATE */
+
diff --git a/src/H5Zfletcher32.c b/src/H5Zfletcher32.c
index b3d82df..62fbfa5 100644
--- a/src/H5Zfletcher32.c
+++ b/src/H5Zfletcher32.c
@@ -16,10 +16,11 @@
* Programmer: Raymond Lu<slu@ncsa.uiuc.edu>
* Jan 3, 2003
*/
-#include "H5private.h"
-#include "H5Eprivate.h"
-#include "H5MMprivate.h"
-#include "H5Zprivate.h"
+
+#include "H5private.h" /* Generic Functions */
+#include "H5Eprivate.h" /* Error handling */
+#include "H5MMprivate.h" /* Memory management */
+#include "H5Zprivate.h" /* Data filters */
#ifdef H5_HAVE_FILTER_FLETCHER32
@@ -47,12 +48,10 @@ static int interface_initialize_g = 0;
*
*-------------------------------------------------------------------------
*/
-static unsigned int H5Z_filter_fletcher32_compute(unsigned short *buf, size_t len)
+static uint32_t H5Z_filter_fletcher32_compute(unsigned short *src, size_t len)
{
- size_t count = len;
- register unsigned int s1 = 0;
- register unsigned int s2 = 0;
- unsigned short *src = buf;
+ size_t count = len; /* Number of bytes left to checksum */
+ uint32_t s1 = 0, s2 = 0; /* Temporary partial checksums */
FUNC_ENTER_NOINIT(H5Z_filter_fletcher32_compute);
@@ -93,8 +92,7 @@ static unsigned int H5Z_filter_fletcher32_compute(unsigned short *buf, size_t le
*
* Purpose: Implement an I/O filter of Fletcher32 Checksum
*
- * Return: Success: size of data plus the size of Fletcher32 value
- *
+ * Return: Success: Size of buffer filtered
* Failure: 0
*
* Programmer: Raymond Lu
@@ -108,42 +106,43 @@ size_t
H5Z_filter_fletcher32 (unsigned flags, size_t UNUSED cd_nelmts, const unsigned UNUSED cd_values[],
size_t nbytes, size_t *buf_size, void **buf)
{
- size_t ret_value = 0;
- void *outbuf = NULL;
-
+ void *outbuf = NULL; /* Pointer to new buffer */
unsigned char *src = (unsigned char*)(*buf);
- unsigned int fletcher = 0;
+ uint32_t fletcher; /* Checksum value */
+ size_t ret_value; /* Return value */
FUNC_ENTER_NOAPI(H5Z_filter_fletcher32, 0);
- assert(sizeof(unsigned int)==4);
+ assert(sizeof(uint32_t)==4);
if (flags & H5Z_FLAG_REVERSE) { /* Read */
- size_t src_nbytes = nbytes;
- unsigned int origin_fletcher;
-
/* Do checksum if it's enabled for read; otherwise skip it
* to save performance. */
- if (!(flags & H5Z_FLAG_SKIP_EDC)) { /* Read */
- unsigned char *tmp_src;
+ if (!(flags & H5Z_FLAG_SKIP_EDC)) {
+ unsigned char *tmp_src; /* Pointer to checksum in buffer */
+ size_t src_nbytes = nbytes; /* Original number of bytes */
+ uint32_t stored_fletcher; /* Stored checksum value */
+ /* Get the stored checksum */
src_nbytes -= FLETCHER_LEN;
tmp_src=src+src_nbytes;
- UINT32DECODE(tmp_src, origin_fletcher);
+ UINT32DECODE(tmp_src, stored_fletcher);
- /* Compute checksum */
+ /* Compute checksum (can't fail) */
fletcher = H5Z_filter_fletcher32_compute((unsigned short*)src,src_nbytes);
- if(origin_fletcher != fletcher)
+ /* Verify computed checksum matches stored checksum */
+ if(stored_fletcher != fletcher)
HGOTO_ERROR(H5E_STORAGE, H5E_READERROR, 0, "data error detected by Fletcher32 checksum");
}
- *buf_size = nbytes - FLETCHER_LEN;
- ret_value = *buf_size;
+ /* Set return values */
+ /* (Re-use the input buffer, just note that the size is smaller by the size of the checksum) */
+ ret_value = nbytes-FLETCHER_LEN;
} else { /* Write */
- unsigned char *dst;
+ unsigned char *dst; /* Temporary pointer to destination buffer */
- /* Compute checksum */
+ /* Compute checksum (can't fail) */
fletcher = H5Z_filter_fletcher32_compute((unsigned short*)src,nbytes);
if (NULL==(dst=outbuf=H5MM_malloc(nbytes+FLETCHER_LEN)))
@@ -152,12 +151,15 @@ H5Z_filter_fletcher32 (unsigned flags, size_t UNUSED cd_nelmts, const unsigned U
/* Copy raw data */
HDmemcpy((void*)dst, (void*)(*buf), nbytes);
- /* Append checksum to raw data */
+ /* Append checksum to raw data for storage */
dst += nbytes;
UINT32ENCODE(dst, fletcher);
- *buf_size = nbytes + FLETCHER_LEN;
+ /* Free input buffer */
H5MM_xfree(*buf);
+
+ /* Set return values */
+ *buf_size = nbytes + FLETCHER_LEN;
*buf = outbuf;
outbuf = NULL;
ret_value = *buf_size;
@@ -168,5 +170,5 @@ done:
H5MM_xfree(outbuf);
FUNC_LEAVE_NOAPI(ret_value);
}
-
#endif /* H5_HAVE_FILTER_FLETCHER32 */
+
diff --git a/src/H5Zshuffle.c b/src/H5Zshuffle.c
index 864875c..bcadbc4 100644
--- a/src/H5Zshuffle.c
+++ b/src/H5Zshuffle.c
@@ -12,14 +12,10 @@
* access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-/*
- * Programmer: Robb Matzke <matzke@llnl.gov>
- * Friday, August 27, 1999
- */
-#include "H5private.h"
-#include "H5Eprivate.h"
-#include "H5MMprivate.h"
-#include "H5Zprivate.h"
+#include "H5private.h" /* Generic Functions */
+#include "H5Eprivate.h" /* Error handling */
+#include "H5MMprivate.h" /* Memory management */
+#include "H5Zprivate.h" /* Data filters */
#ifdef H5_HAVE_FILTER_SHUFFLE
@@ -39,9 +35,8 @@ static int interface_initialize_g = 0;
* Usually, the bytes in each byte position are more related to
* each other and putting them together will increase compression.
*
- * Return: Success:
- *
- * Failure:
+ * Return: Success: Size of buffer filtered
+ * Failure: 0
*
* Programmer: Kent Yang
* Wednesday, November 13, 2002
@@ -127,8 +122,10 @@ H5Z_filter_shuffle(unsigned flags, size_t cd_nelmts, const unsigned cd_values[],
}
} /* end else */
- /* Set the buffer information to return */
+ /* Free the input buffer */
H5MM_xfree(*buf);
+
+ /* Set the buffer information to return */
*buf = dest;
*buf_size=nbytes;
} /* end else */
@@ -140,3 +137,4 @@ done:
FUNC_LEAVE_NOAPI(ret_value);
}
#endif /*H5_HAVE_FILTER_SHUFFLE */
+
diff --git a/src/Makefile.in b/src/Makefile.in
index b108e47..3f82d8e 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -42,7 +42,7 @@ LIB_SRC=H5.c H5A.c H5AC.c H5B.c H5D.c H5E.c H5F.c H5Farray.c H5Fcontig.c \
H5Tcompound.c H5Tconv.c H5Tcset.c H5Tenum.c H5Tfields.c H5Tfixed.c \
H5Tfloat.c H5Tinit.c H5Tnative.c H5Toffset.c H5Topaque.c H5Torder.c \
H5Tpad.c H5Tprecis.c H5Tstrpad.c H5Tvlen.c H5TB.c H5TS.c H5V.c H5Z.c \
- H5Zdeflate.c H5Zszip.c H5Zshuffle.c H5Zfletcher32.c
+ H5Zdeflate.c H5Zshuffle.c H5Zszip.c H5Zfletcher32.c
LIB_OBJ=$(LIB_SRC:.c=.lo)