From dfe9639c9bd2ec7a331a35a2d6de6dde833621c5 Mon Sep 17 00:00:00 2001 From: Raymond Lu Date: Mon, 12 Apr 2004 15:49:36 -0500 Subject: [svn-r8344] Purpose: Internal function change Description: H5T_bit_shift wasn't general enough to handle arbitory start, length. Solution: Make it be so. Platforms tested: h5committest --- src/H5Tbit.c | 41 +++++++++++++++++++++++------------------ src/H5Tconv.c | 8 ++++---- src/H5Tpkg.h | 2 +- 3 files changed, 28 insertions(+), 23 deletions(-) diff --git a/src/H5Tbit.c b/src/H5Tbit.c index c9b2b4c..5f4cfe4 100644 --- a/src/H5Tbit.c +++ b/src/H5Tbit.c @@ -167,50 +167,55 @@ H5T_bit_copy (uint8_t *dst, size_t dst_offset, const uint8_t *src, * Purpose: Simulation of hardware shifting. Shifts a bit vector * in a way similar to shifting a variable value, like * value <<= 3, or value >>= 16. SHIFT_DIST is positive for - * left shift, negative for right shift. + * left shift, negative for right shift. The bit vector starts + * at OFFSET and is SIZE long. * * Return: void * * Programmer: Raymond Lu - * Wednesday, Febuary 4, 2004 + * Monday, April 12, 2004 * * Modifications: * - * Can generalize it to handle a bit vector of any START - * position and any SIZE. - * *------------------------------------------------------------------------- */ void -H5T_bit_shift (uint8_t *buf, ssize_t shift_dist, size_t buf_size) +H5T_bit_shift (uint8_t *buf, ssize_t shift_dist, size_t offset, size_t size) { uint8_t *tmp_buf; - size_t buf_size_bit = 8*buf_size; FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5T_bit_shift); /* Sanity check */ assert(buf); - assert(buf_size); + assert(size); if(!shift_dist) goto done; - if(ABS(shift_dist) >= buf_size_bit) { - HDmemset(buf,0,buf_size); + if(ABS(shift_dist) >= size) { + H5T_bit_set(buf, offset, size, 0); goto done; } - tmp_buf = (uint8_t*)H5MM_calloc(buf_size); + tmp_buf = (uint8_t*)H5MM_calloc(size/8+1); assert(tmp_buf); /* Shift vector by making copies */ - if(shift_dist > 0) /* left shift */ - H5T_bit_copy (tmp_buf, (size_t)shift_dist, buf, 0, (size_t)(buf_size_bit-shift_dist)); - else /* right shift */ - H5T_bit_copy(tmp_buf, 0, buf, (size_t)-shift_dist, (size_t)(buf_size_bit+shift_dist)); - - /* Copy back the vector */ - HDmemcpy(buf,tmp_buf,buf_size); + if(shift_dist > 0) { /* left shift */ + /* Copy part to be shifted to a temporary buffer */ + H5T_bit_copy (tmp_buf, 0, buf, offset, (size_t)(size-shift_dist)); + + /* Copy it back to the original buffer */ + H5T_bit_copy (buf, offset+shift_dist, tmp_buf, 0, (size_t)(size-shift_dist)); + + /* Zero-set the left part*/ + H5T_bit_set(buf, offset, shift_dist, 0); + } else { /* right shift */ + shift_dist = - shift_dist; + H5T_bit_copy(tmp_buf, 0, buf, offset+shift_dist, (size_t)(size-shift_dist)); + H5T_bit_copy (buf, offset, tmp_buf, 0, (size_t)(size-shift_dist)); + H5T_bit_set(buf, offset+size-shift_dist, shift_dist, 0); + } /* Free temporary buffer */ H5MM_xfree(tmp_buf); diff --git a/src/H5Tconv.c b/src/H5Tconv.c index 23c5adc..0cd615b 100644 --- a/src/H5Tconv.c +++ b/src/H5Tconv.c @@ -8600,7 +8600,7 @@ H5T_conv_f_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, * Shift mantissa part by exponent minus mantissa size(right shift), * or by mantissa size minus exponent(left shift). */ - H5T_bit_shift(int_buf, (ssize_t)(expo-src.u.f.msize), buf_size); + H5T_bit_shift(int_buf, (ssize_t)(expo-src.u.f.msize), 0, buf_size*8); /* Convert to integer representation if negative. * equivalent to ~(value - 1). @@ -8969,7 +8969,7 @@ H5T_conv_i_f (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, } /* Right shift to drop off extra bits */ - H5T_bit_shift(int_buf, (ssize_t)(dst.u.f.msize-first), buf_size); + H5T_bit_shift(int_buf, (ssize_t)(dst.u.f.msize-first), 0, buf_size*8); if(do_round) { H5T_bit_inc(int_buf, 0, buf_size*8); @@ -8989,7 +8989,7 @@ H5T_conv_i_f (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, /* Right shift 1 bit to let the carried 1 fit in the mantissa, * and increment exponent by 1. */ - H5T_bit_shift(int_buf, -1, buf_size); + H5T_bit_shift(int_buf, -1, 0, buf_size*8); expo++; } } @@ -8997,7 +8997,7 @@ H5T_conv_i_f (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, } else { /* The bit sequence can fit mantissa part. Left shift to fit in from high-order of * bit position. */ - H5T_bit_shift(int_buf, (ssize_t)(dst.u.f.msize-first), buf_size); + H5T_bit_shift(int_buf, (ssize_t)(dst.u.f.msize-first), 0, buf_size*8); } diff --git a/src/H5Tpkg.h b/src/H5Tpkg.h index 70a4f56..e3e6226 100644 --- a/src/H5Tpkg.h +++ b/src/H5Tpkg.h @@ -1070,7 +1070,7 @@ H5_DLL herr_t H5T_conv_i32le_f64le(hid_t src_id, hid_t dst_id, /* Bit twiddling functions */ H5_DLL void H5T_bit_copy(uint8_t *dst, size_t dst_offset, const uint8_t *src, size_t src_offset, size_t size); -H5_DLL void H5T_bit_shift(uint8_t *buf, ssize_t shift_dist, size_t buf_size); +H5_DLL void H5T_bit_shift(uint8_t *buf, ssize_t shift_dist, size_t offset, size_t size); H5_DLL void H5T_bit_set(uint8_t *buf, size_t offset, size_t size, hbool_t value); H5_DLL hsize_t H5T_bit_get_d(uint8_t *buf, size_t offset, size_t size); -- cgit v0.12