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+static char *FileHeader = "\n\
+/*-------------------------------------------------------------------------\n\
+ * Copyright (C) 1997 National Center for Supercomputing Applications. \n\
+ * All rights reserved. \n\
+ * \n\
+ *-------------------------------------------------------------------------";
+/*
+ *
+ * Created: H5detect.c
+ * 10 Aug 1997
+ * Robb Matzke
+ *
+ * Purpose: This code was borrowed heavily from the `detect.c'
+ * program in the AIO distribution from Lawrence
+ * Livermore National Laboratory.
+ *
+ * Detects machine byte order and floating point
+ * format and generates a C source file (native.c)
+ * to describe those paramters.
+ *
+ * Assumptions: We have an ANSI compiler. We're on a Unix like
+ * system or configure has detected those Unix
+ * features which aren't available. We're not
+ * running on a Vax or other machine with mixed
+ * endianess.
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include <assert.h>
+#include <math.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+
+#define MAXDETECT 16
+
+#ifndef MIN
+# define MIN(X,Y) ((X)<(Y)?(X):(Y))
+#endif
+
+/*
+ * This structure holds information about a type that
+ * was detected.
+ */
+typedef struct detected_t {
+ char *typename;
+ char *varname;
+ int size;
+ int padding;
+ int perm[32];
+ int sign;
+ int mpos, msize, imp;
+ int epos, esize, bias;
+} detected_t;
+
+static void print_results (int nd, detected_t *d);
+static void iprint (detected_t*, int);
+static void print_known_formats (detected_t*, int);
+static int byte_cmp (int, void*, void*);
+static int bit_cmp (int, int*, void*, void*);
+static void fix_order (int, int, int, int*, char**);
+static void fix_padding (detected_t*);
+static int imp_bit (int, int*, void*, void*);
+static int find_bias (int, int, int, int*, void*);
+static void print_header (void);
+
+
+/*-------------------------------------------------------------------------
+ * For convenience, we place here in a table descriptions of all
+ * architectures we've seen so far. That way we can print a description
+ * of the system on which the program is run. We place the system name
+ * in the VARNAME field.
+ *-------------------------------------------------------------------------
+ */
+#define LE {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15, \
+ 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31}
+#define LE_1 LE
+#define LE_2 LE
+#define LE_4 LE
+#define LE_8 LE
+
+#define BE_1 {0}
+#define BE_2 {1,0}
+#define BE_4 {3,2,1,0}
+#define BE_8 {7,6,5,4,3,2,1,0}
+
+#define INTEGER 0,0,0,0,0,0,0
+
+static detected_t Known[] = {
+ /* Single-byte quantities */
+ {"char", "Byte addressable",
+ 1, 0, LE_1, INTEGER},
+
+ /* Little-endian fixed-point */
+ {"int16", "Little-endian",
+ 2, 0, LE_2, INTEGER},
+ {"int32", "Little-endian",
+ 4, 0, LE_4, INTEGER},
+
+ /* Big-endian fixed-point */
+ {"int16", "Big-endian",
+ 2, 0, BE_2, INTEGER},
+ {"int32", "Big-endian",
+ 4, 0, BE_4, INTEGER},
+
+ /* Little-endian IEEE floating-point */
+ {"float32", "Little-endian IEEE",
+ 4, 0, LE_4, 31, 0, 23, 1, 23, 8, 127},
+ {"float64", "Little-endian IEEE",
+ 8, 0, LE_8, 63, 0, 52, 1, 52, 11, 1023},
+
+ /* Big-endian IEEE floating-point */
+ {"float32", "Big-endian IEEE",
+ 4, 0, BE_4, 31, 0, 23, 1, 23, 8, 127},
+ {"float64", "Big-endian IEEE",
+ 8, 0, BE_8, 63, 0, 52, 1, 52, 11, 1023},
+};
+
+
+/*-------------------------------------------------------------------------
+ * Function: DETECT_I
+ *
+ * Purpose: This macro takes a type like `int' and a base name like
+ * `nati' and detects the byte order. The VAR is used to
+ * construct the names of the C variables defined.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 12 1996
+ *
+ * Modifications:
+ *
+ * Robb Matzke, 4 Nov 1996
+ * The INFO.perm now contains `-1' for bytes that aren't used and
+ * are always zero. This happens on the Cray for `short' where
+ * sizeof(short) is 8, but only the low-order 4 bytes are ever used.
+ *
+ * Robb Matzke, 4 Nov 1996
+ * Added a `padding' field to indicate how many zero bytes appear to
+ * the left (N) or right (-N) of the value.
+ *
+ * Robb Matzke, 5 Nov 1996
+ * Removed HFILE and CFILE arguments.
+ *
+ *-------------------------------------------------------------------------
+ */
+#define DETECT_I(TYPE,TYPE_S,VAR,VAR_S,INFO) { \
+ TYPE _v; \
+ int _i, _j; \
+ unsigned char *_x; \
+ memset (&INFO, 0, sizeof(INFO)); \
+ INFO.typename = TYPE_S; \
+ INFO.varname = VAR_S; \
+ INFO.size = sizeof(TYPE); \
+ for (_i=sizeof(TYPE),_v=0; _i>0; --_i) _v = (_v<<8) + _i; \
+ for (_i=0,_x=(unsigned char *)&_v; _i<sizeof(TYPE); _i++) { \
+ _j = (*_x++)-1; \
+ assert (_j<(signed)sizeof(TYPE)); \
+ INFO.perm[_i] = _j; \
+ } \
+ fix_padding (&(INFO)); \
+ if (!strncmp(TYPE_S, "unsigned", 8)) INFO.sign = 0; \
+ else INFO.sign = 1; \
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: DETECT_F
+ *
+ * Purpose: This macro takes a floating point type like `double' and
+ * a base name like `natd' and detects byte order, mantissa
+ * location, exponent location, sign bit location, presence or
+ * absence of implicit mantissa bit, and exponent bias and
+ * initializes a detected_t structure with those properties.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 12 1996
+ *
+ * Modifications:
+ *
+ * Robb Matzke, 14 Aug 1996
+ * The byte order detection has been changed because on the Cray
+ * the last pass causes a rounding to occur that causes the least
+ * significant mantissa byte to change unexpectedly.
+ *
+ * Robb Matzke, 5 Nov 1996
+ * Removed HFILE and CFILE arguments.
+ *-------------------------------------------------------------------------
+ */
+#define DETECT_F(TYPE,TYPE_S,VAR,VAR_S,INFO) { \
+ TYPE _v1, _v2, _v3; \
+ int _i, _j, _first=(-1), _last=(-1); \
+ char *_mesg; \
+ \
+ memset (&INFO, 0, sizeof(INFO)); \
+ INFO.typename = TYPE_S; \
+ INFO.varname = VAR_S; \
+ INFO.size = sizeof(TYPE); \
+ INFO.padding = 0; \
+ \
+ /* Byte Order */ \
+ for (_i=0,_v1=0.0,_v2=1.0; _i<sizeof(TYPE); _i++) { \
+ _v3 = _v1; _v1 += _v2; _v2 /= 256.0; \
+ if ((_j=byte_cmp(sizeof(TYPE), &_v3, &_v1))>=0) { \
+ if (0==_i || INFO.perm[_i-1]!=_j) { \
+ INFO.perm[_i] = _j; \
+ _last = _i; \
+ if (_first<0) _first = _i; \
+ } \
+ } \
+ } \
+ fix_order (sizeof(TYPE), _first, _last, INFO.perm, &_mesg); \
+ \
+ /* Implicit mantissa bit */ \
+ _v1 = 0.5; \
+ _v2 = 1.0; \
+ INFO.imp = imp_bit (sizeof(TYPE), INFO.perm, &_v1, &_v2); \
+ \
+ /* Sign bit */ \
+ _v1 = 1.0; \
+ _v2 = -1.0; \
+ INFO.sign = bit_cmp (sizeof(TYPE), INFO.perm, &_v1, &_v2); \
+ \
+ /* Mantissa */ \
+ INFO.mpos = 0; \
+ \
+ _v1 = 1.0; \
+ _v2 = 1.5; \
+ INFO.msize = bit_cmp (sizeof(TYPE), INFO.perm, &_v1, &_v2); \
+ INFO.msize += 1 + (INFO.imp?0:1) - INFO.mpos; \
+ \
+ /* Exponent */ \
+ INFO.epos = INFO.mpos + INFO.msize; \
+ \
+ INFO.esize = INFO.sign - INFO.epos; \
+ \
+ _v1 = 1.0; \
+ INFO.bias = find_bias (INFO.epos, INFO.esize, INFO.imp, INFO.perm, &_v1); \
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: print_results
+ *
+ * Purpose: Prints information about the detected data types.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 14, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+print_results (int nd, detected_t *d) {
+
+ int i, j;
+
+ printf ("#define DEFAULT_INTEGER_FIELDS {FALSE,0,0,0,0,0}\n\n");
+ printf ("#define FALSE 0\n");
+ printf ("#define TRUE 1\n");
+
+ printf ("\ntypedef struct {\n");
+ printf (" uintn class, bytes, padding, size, align;\n");
+ printf (" uintn order[32], sign, imp, mloc, msize, eloc, esize;\n");
+ printf (" uint32 bias;\n");
+ printf ("};\n\n");
+
+ for (i=0; i<nd; i++) {
+ printf ("\n/*\n");
+ iprint (d+i, 0);
+ print_known_formats (d+i, 0);
+ printf (" */\n");
+ printf ("const H5T_desc_t H5T_%s[1] = {{\n",
+ d[i].varname);
+ printf (" /* Class */ %s,\n",
+ d[i].msize?"H5T_FLOAT":"H5T_FIXED");
+ printf (" /* Number of bytes */ %d,\n", d[i].size);
+ printf (" /* Zero padding */ %d,\n", d[i].padding);
+ printf (" /* sizeof() */ %d,\n",
+ d[i].size + abs (d[i].padding));
+
+ /* alignment isn't detected yet */
+ printf (" /* Alignment */ %d,\n",
+ d[i].size + abs (d[i].padding));
+
+ printf (" /* Byte order */ {");
+ for (j=0; j<32; j++) {
+ if (j && 0==j%8) printf ("\n ");
+ printf ("%3d%s", j<d[i].size?d[i].perm[j]:-1, j+1<32?",":"");
+ }
+ printf ("},\n");
+
+ if (d[i].msize) {
+ printf (" /* Float sign loc */ %d,\n", d[i].sign);
+ printf (" /* Float implicit bit */ %s,\n",
+ d[i].imp?"TRUE":"FALSE");
+ printf (" /* Float mantissa loc */ %d,\n", d[i].mpos);
+ printf (" /* Float matnissa size */ %d,\n", d[i].msize);
+ printf (" /* Float exponent loc */ %d,\n", d[i].epos);
+ printf (" /* Float exponent size */ %d,\n", d[i].esize);
+ printf (" /* Float exponent bias */ 0x%x,\n", d[i].bias);
+ } else {
+ printf (" /* Signed? */ %s,\n",
+ d[i].sign?"TRUE":"FALSE");
+ printf (" DEFAULT_INTEGER_FIELDS,\n");
+ }
+ printf ("}};\n\n");
+ }
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: tprint
+ *
+ * Purpose: Prints a binary number beginning with the most
+ * significant bit and continuing to the least
+ * significant bit.
+ *
+ * If PERM is the null pointer then it isn't used and
+ * _A is assumed to be in big endian order.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+#if 0
+static void
+tprint (int nbytes, int *perm, void *_a) {
+
+ int i, j;
+ unsigned char *a = (unsigned char *)_a;
+ unsigned char b;
+
+ for (i=0; i<nbytes; i++) {
+ if (perm) {
+ assert (perm[i]<nbytes);
+ b = a[perm[i]];
+ } else {
+ b = a[i];
+ }
+ for (j=0; j<8; j++,b<<=1) putchar (b & 0x80 ? '1' : '0');
+ if (i+1<nbytes) {
+ putchar (' ');
+ if (0==(i+1)%4) putchar (' ');
+ }
+ }
+ putchar ('\n');
+}
+#endif
+
+
+/*-------------------------------------------------------------------------
+ * Function: iprint
+ *
+ * Purpose: Prints information about the fields of a floating point
+ * format.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+iprint (detected_t *d, int indent) {
+
+ int i, j, k;
+
+ /*
+ * Print the byte ordering above the bit fields.
+ */
+ printf ("%*s * ", indent, "");
+ for (i=d->size-1; i>=0; --i) {
+ printf ("%4d", d->perm[i]);
+ if (i>0) fputs (" ", stdout);
+ if (0==i%4) putchar (' ');
+ }
+ putchar ('\n');
+
+ /*
+ * Print the bit fields
+ */
+ printf ("%*s * ", indent, "");
+ for (i=d->size-1,k=d->size*8-1; i>=0; --i) {
+ for (j=7; j>=0; --j) {
+ if (k==d->sign && d->msize) {
+ putchar ('S');
+ } else if (k>=d->epos && k<d->epos+d->esize) {
+ putchar ('E');
+ } else if (k>=d->mpos && k<d->mpos+d->msize) {
+ putchar ('M');
+ } else {
+ putchar ('I');
+ }
+ --k;
+ }
+ if (i>0) {
+ putchar (' ');
+ if (0==i%4) putchar (' ');
+ }
+ }
+ putchar ('\n');
+
+ /*
+ * Is there an implicit bit in the mantissa.
+ */
+ if (d->msize) {
+ printf ("%*s * Implicit bit? %s\n", indent, "", d->imp?"yes":"no");
+ }
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: print_known_formats
+ *
+ * Purpose: Prints archetecture names for the specified format
+ * description, if any.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+print_known_formats (detected_t *d, int indent) {
+
+ int i, j, diff;
+ int n=sizeof(Known)/sizeof(Known[0]);
+
+ for (i=0; i<n; i++) {
+ if (d->size != Known[i].size) continue;
+ for (j=diff=0; !diff && j<d->size; j++) {
+ if (d->perm[j] != Known[i].perm[j]) diff = 1;
+ }
+ if (diff) continue;
+
+ /* if (d->sign != Known[i].sign) continue;*/
+ if (d->mpos != Known[i].mpos) continue;
+ if (d->msize != Known[i].msize) continue;
+ if (d->imp != Known[i].imp) continue;
+ if (d->epos != Known[i].epos) continue;
+ if (d->esize != Known[i].esize) continue;
+ if (d->bias != Known[i].bias) continue;
+
+ printf ("%*s * %s %s\n",
+ indent, "", Known[i].varname, Known[i].typename);
+ }
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: byte_cmp
+ *
+ * Purpose: Compares two chunks of memory A and B and returns the
+ * byte index into those arrays of the first byte that
+ * differs between A and B.
+ *
+ * Return: Success: Index of differing byte.
+ *
+ * Failure: -1 if all bytes are the same.
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 12, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+byte_cmp (int n, void *_a, void *_b) {
+
+ register int i;
+ unsigned char *a = (unsigned char *)_a;
+ unsigned char *b = (unsigned char *)_b;
+
+ for (i=0; i<n; i++) if (a[i]!=b[i]) return i;
+ return -1;
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: bit_cmp
+ *
+ * Purpose: Compares two bit vectors and returns the index for the
+ * first bit that differs between the two vectors. The
+ * size of the vector is NBYTES. PERM is a mapping from
+ * actual order to little endian.
+ *
+ * Return: Success: Index of first differing bit.
+ *
+ * Failure: -1
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+bit_cmp (int nbytes, int *perm, void *_a, void *_b) {
+
+ int i, j;
+ unsigned char *a = (unsigned char *)_a;
+ unsigned char *b = (unsigned char *)_b;
+ unsigned char aa, bb;
+
+ for (i=0; i<nbytes; i++) {
+ assert (perm[i]<nbytes);
+ if ((aa=a[perm[i]]) != (bb=b[perm[i]])) {
+ for (j=0; j<8; j++,aa>>=1,bb>>=1) {
+ if ((aa & 1) != (bb & 1)) return i*8 + j;
+ }
+ assert ("INTERNAL ERROR" && 0);
+ }
+ }
+ return -1;
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: fix_order
+ *
+ * Purpose: Given an array PERM with elements FIRST through LAST
+ * initialized with zero origin byte numbers, this function
+ * creates a permutation vector that maps the actual order
+ * of a floating point number to little-endian.
+ *
+ * This function assumes that the mantissa byte ordering
+ * implies the total ordering.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+fix_order (int n, int first, int last, int *perm, char **mesg) {
+
+ int i;
+
+ if (first+1<last) {
+ /*
+ * We have at least three points to consider.
+ */
+ if (perm[last]<perm[last-1] && perm[last-1]<perm[last-2]) {
+ /*
+ * Little endian.
+ */
+ if (mesg) *mesg = "Little-endian";
+ for (i=0; i<n; i++) perm[i] = i;
+
+ } else if (perm[last]>perm[last-1] && perm[last-1]>perm[last-2]) {
+ /*
+ * Big endian.
+ */
+ if (mesg) *mesg = "Big-endian";
+ for (i=0; i<n; i++) perm[i] = (n-1)-i;
+
+ } else {
+ /*
+ * Bi-endian machines like VAX.
+ */
+ assert (0==n/2);
+ if (mesg) *mesg = "VAX";
+ for (i=0; i<n; i+=2) {
+ perm[i] = (n-2)-i;
+ perm[i+1] = (n-1)-i;
+ }
+ }
+ } else {
+ fprintf (stderr,
+ "Failed to detect byte order of %d-byte floating point.\n", n);
+ exit (1);
+ }
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: fix_padding
+ *
+ * Purpose: The permutation can have negative values at the beginning
+ * or end which represent zero padding. The amount of padding
+ * is subtracted from the size, the negative values are removed
+ * from the permutation, and the `padding' field is set to an
+ * appropriate value.
+ *
+ * If N bytes of padding appear to the left (lower address) of
+ * the value, then `padding=N'. If N bytes of padding appear
+ * to the right of the value then `padding=(-N)'.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Nov 4 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+fix_padding (detected_t *d) {
+
+ int i, n;
+
+ if (d->perm[0]<0) {
+ /*
+ * Left padding.
+ */
+ for (n=0; n<d->size && d->perm[n]<0; n++) /*void*/;
+ for (i=n; i<d->size; i++) d->perm[i-n] = d->perm[i];
+ for (i=d->size-n; i<d->size; i++) d->perm[i] = 0;
+ d->padding = n;
+ d->size -= n;
+
+ } else if (d->perm[d->size-1]<0) {
+ /*
+ * Right padding.
+ */
+ for (n=0; n<d->size && d->perm[d->size-(n+1)]; n++) /*void*/;
+ for (i=d->size-n; i<d->size; i++) d->perm[i] = 0;
+ d->padding = -n;
+ d->size -= n;
+
+ } else {
+ /*
+ * No padding.
+ */
+ d->padding = 0;
+ }
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: imp_bit
+ *
+ * Purpose: Looks for an implicit bit in the mantissa. The value
+ * of _A should be 1.0 and the value of _B should be 0.5.
+ * Some floating-point formats discard the most significant
+ * bit of the mantissa after normalizing since it will always
+ * be a one (except for 0.0). If this is true for the native
+ * floating point values stored in _A and _B then the function
+ * returns non-zero.
+ *
+ * This function assumes that the exponent occupies higher
+ * order bits than the mantissa and that the most significant
+ * bit of the mantissa is next to the least signficant bit
+ * of the exponent.
+ *
+ *
+ * Return: Success: Non-zero if the most significant bit
+ * of the mantissa is discarded (ie, the
+ * mantissa has an implicit `one' as the
+ * most significant bit). Otherwise,
+ * returns zero.
+ *
+ * Failure: exit(1)
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ * Robb Matzke, 6 Nov 1996
+ * Fixed a bug that occurs with non-implicit architectures.
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+imp_bit (int n, int *perm, void *_a, void *_b) {
+
+ unsigned char *a = (unsigned char *)_a;
+ unsigned char *b = (unsigned char *)_b;
+ int changed, major, minor;
+ int msmb; /*most significant mantissa bit*/
+
+ /*
+ * Look for the least significant bit that has changed between
+ * A and B. This is the least significant bit of the exponent.
+ */
+ changed = bit_cmp (n, perm, a, b);
+ assert (changed>=0);
+
+ /*
+ * The bit to the right (less significant) of the changed bit should
+ * be the most significant bit of the mantissa. If it is non-zero
+ * then the format does not remove the leading `1' of the mantissa.
+ */
+ msmb = changed-1;
+ major = msmb / 8;
+ minor = msmb % 8;
+
+ return (a[perm[major]] >> minor) & 0x01 ? 0 : 1;
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: find_bias
+ *
+ * Purpose: Determines the bias of the exponent. This function should
+ * be called with _A having a value of `1'.
+ *
+ * Return: Success: The exponent bias.
+ *
+ * Failure:
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 13, 1996
+ *
+ * Modifications:
+ *
+ * Robb Matzke, 6 Nov 1996
+ * Fixed a bug with non-implicit architectures returning the
+ * wrong exponent bias.
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+find_bias (int epos, int esize, int imp, int *perm, void *_a) {
+
+
+ unsigned char *a = (unsigned char *)_a;
+ unsigned char mask;
+ unsigned long b, shift=0, nbits, bias=0;
+
+ while (esize>0) {
+ nbits = MIN (esize, (8 - epos % 8));
+ mask = (1<<nbits) - 1;
+ b = (a[perm[epos/8]] >> (epos % 8)) & mask;
+ bias |= b << shift;
+
+ shift += nbits;
+ esize -= nbits;
+ epos += nbits;
+ }
+
+ return bias - (imp?0:1);
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: print_header
+ *
+ * Purpose: Prints the C file header for the generated file.
+ *
+ * Return: void
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Mar 12 1997
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+print_header (void) {
+
+ time_t now = time (NULL);
+ struct tm *tm = localtime (&now);
+ struct passwd *pwd = getpwuid (getuid());
+ char real_name[30], *comma;
+ char host_name[256];
+ int i, n;
+ char *s;
+ static char *month_name[] = {
+ "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+ "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
+ static char *purpose = "\
+This machine-generated source code contains\n\
+information about the various integer and\n\
+floating point numeric formats found on this\n\
+architecture. The parameters below should be\n\
+checked carefully and errors reported to the\n\
+HDF5 maintainer.\n\
+\n\
+Each of the numeric formats listed below are\n\
+printed from most significant bit to least\n\
+significant bit even though the actual bytes\n\
+might be stored in a different order in\n\
+memory. The integers above each binary byte\n\
+indicate the relative order of the bytes in\n\
+memory; little-endian machines have\n\
+decreasing numbers while big-endian machines\n\
+have increasing numbers.\n\
+\n\
+The fields of the numbers are printed as\n\
+letters with `S' for the mantissa sign bit,\n\
+`M' for the mantissa magnitude, and `E' for\n\
+the exponent. The exponent has an associated\n\
+bias which can be subtracted to find the\n\
+true exponent. The radix point is assumed\n\
+to be before the first `M' bit. Any bit\n\
+not falling into one of these categories\n\
+is printed as a question mark, as are all\n\
+bits of integer quantities.\n\
+\n\
+If the most significant bit of the normalized\n\
+mantissa (always a `1' except for `0.0') is\n\
+not stored then an `implicit=yes' appears\n\
+under the field description. In thie case,\n\
+the radix point is still assumed to be\n\
+before the first `M' but after the implicit\n\
+bit.";
+
+ /*
+ * The real name is the first item from the passwd gecos field.
+ */
+ if (pwd) {
+ if ((comma=strchr(pwd->pw_gecos,','))) {
+ n = MIN (sizeof(real_name)-1, comma - pwd->pw_gecos);
+ strncpy (real_name, pwd->pw_gecos, n);
+ real_name[n] = '\0';
+ } else {
+ strncpy (real_name, pwd->pw_gecos, sizeof(real_name));
+ real_name[sizeof(real_name)-1] = '\0';
+ }
+ } else {
+ real_name[0] = '\0';
+ }
+
+ /*
+ * The FQDM of this host or the empty string.
+ */
+ if (gethostname(host_name, sizeof(host_name))<0) host_name[0] = '\0';
+
+
+ /*
+ * The file header: warning, copyright notice, build information.
+ */
+ printf ("/*\n * DO NOT EDIT THIS FILE--IT IS MACHINE GENERATED!\n */\n\n");
+ puts (FileHeader); /*the copyright notice--see top of this file*/
+
+ printf (" *\n * Created:\t\t%s %2d, %4d\n",
+ month_name[tm->tm_mon], tm->tm_mday, 1900+tm->tm_year);
+ if (pwd || real_name[0] || host_name[0]) {
+ printf (" *\t\t\t");
+ if (real_name[0]) printf ("%s <", real_name);
+ if (pwd) fputs (pwd->pw_name, stdout);
+ if (host_name[0]) printf ("@%s", host_name);
+ if (real_name[0]) printf (">");
+ putchar ('\n');
+ }
+
+ printf (" *\n * Purpose:\t\t");
+ for (s=purpose; *s; s++) {
+ putchar (*s);
+ if ('\n'==*s) printf (" *\t\t\t");
+ }
+
+ printf (" *\n * Modifications:\n *\n");
+ printf (" *\tDO NOT MAKE MODIFICATIONS TO THIS FILE!\n");
+ printf (" *\tIt was generated by code in `H5detect.c'.\n");
+
+ printf (" *\n *");
+ for (i=0; i<73; i++) putchar ('-');
+ printf ("\n */\n\n");
+
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function: main
+ *
+ * Purpose: Main entry point.
+ *
+ * Return: Success: exit(0)
+ *
+ * Failure: exit(1)
+ *
+ * Programmer: Robb Matzke
+ * matzke@llnl.gov
+ * Jun 12, 1996
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+main (int argc, char *argv[]) {
+
+ detected_t d[MAXDETECT];
+ int nd=0;
+
+ print_header();
+
+ DETECT_I (signed char, "signed char", natsc, "natsc", d[nd]); nd++;
+ DETECT_I (unsigned char, "unsigned char", natuc, "natuc", d[nd]); nd++;
+ DETECT_I (short, "short", nats, "natss", d[nd]); nd++;
+ DETECT_I (unsigned short, "unsigned short", nats, "natus", d[nd]); nd++;
+ DETECT_I (int, "int", nati, "natsi", d[nd]); nd++;
+ DETECT_I (unsigned int, "unsigned int", nati, "natui", d[nd]); nd++;
+ DETECT_I (long, "long", natl, "natsl", d[nd]); nd++;
+ DETECT_I (unsigned long, "unsigned long", natl, "natul", d[nd]); nd++;
+ DETECT_F (float, "float", natf, "natf", d[nd]); nd++;
+ DETECT_F (double, "double", natd, "natd", d[nd]); nd++;
+
+ print_results (nd, d);
+ exit (0);
+}