wcsutil.h

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/*============================================================================
  WCSLIB 8.2 - an implementation of the FITS WCS standard.
  Copyright (C) 1995-2023, Mark Calabretta
 
  This file is part of WCSLIB.
 
  WCSLIB is free software: you can redistribute it and/or modify it under the
  terms of the GNU Lesser General Public License as published by the Free
  Software Foundation, either version 3 of the License, or (at your option)
  any later version.
 
  WCSLIB is distributed in the hope that it will be useful, but WITHOUT ANY
  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
  more details.
 
  You should have received a copy of the GNU Lesser General Public License
  along with WCSLIB.  If not, see http://www.gnu.org/licenses.
 
  Author: Mark Calabretta, Australia Telescope National Facility, CSIRO.
  http://www.atnf.csiro.au/people/Mark.Calabretta
  $Id: wcsutil.h,v 8.2.1.1 2023/11/16 10:05:57 mcalabre Exp mcalabre $
*=============================================================================
*
* WCSLIB 8.2 - C routines that implement the FITS World Coordinate System
* (WCS) standard.  Refer to the README file provided with WCSLIB for an
* overview of the library.
*
*
* Summary of the wcsutil routines
* -------------------------------
* Simple utility functions.  With the exception of wcsdealloc(), these
* functions are intended for internal use only by WCSLIB.
*
* The internal-use functions are documented here solely as an aid to
* understanding the code.  They are not intended for external use - the API
* may change without notice!
*
*
* wcsdealloc() - free memory allocated by WCSLIB functions
* --------------------------------------------------------
* wcsdealloc() invokes the free() system routine to free memory.
* Specifically, it is intended to free memory allocated (using calloc()) by
* certain WCSLIB functions (e.g. wcshdo(), wcsfixi(), fitshdr()), which it is
* the user's responsibility to deallocate.
*
* In certain situations, for example multithreading, it may be important that
* this be done within the WCSLIB sharable library's runtime environment.
*
* PLEASE NOTE: wcsdealloc() must not be used in place of the destructors for
* particular structs, such as wcsfree(), celfree(), etc.
*
* Given and returned:
*   ptr       void*     Address of the allocated memory.
*
* Function return value:
*             void
*
*
* wcsutil_strcvt() - Copy character string with padding
* -----------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_strcvt() copies one character string to another up to the specified
* maximum number of characters.
*
* If the given string is null-terminated, then the NULL character copied to
* the returned string, and all characters following it up to the specified
* maximum, are replaced with the specified substitute character, either blank
* or NULL.
*
* If the source string is not null-terminated and the substitute character is
* blank, then copy the maximum number of characters and do nothing further.
* However, if the substitute character is NULL, then the last character and
* all consecutive blank characters preceding it will be replaced with NULLs.
*
* Used by the Fortran wrapper functions in translating C strings into Fortran
* CHARACTER variables and vice versa.
*
* Given:
*   n         int       Maximum number of characters to copy.
*
*   c         char      Substitute character, either NULL or blank (anything
*                       other than NULL).
*
*   nt        int       If true, then dst is of length n+1, with the last
*                       character always set to NULL.
*
*   src       char[]    Character string to be copied.  If null-terminated,
*                       then need not be of length n, otherwise it must be.
*
* Returned:
*   dst       char[]    Destination character string, which must be long
*                       enough to hold n characters.  Note that this string
*                       will not be null-terminated if the substitute
*                       character is blank.
*
* Function return value:
*             void
*
*
* wcsutil_blank_fill() - Fill a character string with blanks
* ----------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_blank_fill() pads a character sub-string with blanks starting with
* the terminating NULL character (if any).
*
* Given:
*   n         int       Length of the sub-string.
*
* Given and returned:
*   c         char[]    The character sub-string, which will not be
*                       null-terminated on return.
*
* Function return value:
*             void
*
*
* wcsutil_null_fill() - Fill a character string with NULLs
* --------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_null_fill() strips trailing blanks from a string (or sub-string) and
* propagates the terminating NULL character (if any) to the end of the string.
*
* If the string is not null-terminated, then the last character and all
* consecutive blank characters preceding it will be replaced with NULLs.
*
* Mainly used in the C library to strip trailing blanks from FITS keyvalues.
* Also used to make character strings intelligible in the GNU debugger, which
* prints the rubbish following the terminating NULL character, thereby
* obscuring the valid part of the string.
*
* Given:
*   n         int       Number of characters.
*
* Given and returned:
*   c         char[]    The character (sub-)string.
*
* Function return value:
*             void
*
*
* wcsutil_all_ival() - Test if all elements an int array have a given value
* -------------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_all_ival() tests whether all elements of an array of type int all
* have the specified value.
*
* Given:
*   nelem     int       The length of the array.
*
*   ival      int       Value to be tested.
*
*   iarr      const int[]
*                       Pointer to the first element of the array.
*
* Function return value:
*             int       Status return value:
*                         0: Not all equal.
*                         1: All equal.
*
*
* wcsutil_all_dval() - Test if all elements a double array have a given value
* ---------------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_all_dval() tests whether all elements of an array of type double all
* have the specified value.
*
* Given:
*   nelem     int       The length of the array.
*
*   dval      int       Value to be tested.
*
*   darr      const double[]
*                       Pointer to the first element of the array.
*
* Function return value:
*             int       Status return value:
*                         0: Not all equal.
*                         1: All equal.
*
*
* wcsutil_all_sval() - Test if all elements a string array have a given value
* ---------------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_all_sval() tests whether the elements of an array of type
* char (*)[72] all have the specified value.
*
* Given:
*   nelem     int       The length of the array.
*
*   sval      const char *
*                       String to be tested.
*
*   sarr      const char (*)[72]
*                       Pointer to the first element of the array.
*
* Function return value:
*             int       Status return value:
*                         0: Not all equal.
*                         1: All equal.
*
*
* wcsutil_allEq() - Test for equality of a particular vector element
* ------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_allEq() tests for equality of a particular element in a set of
* vectors.
*
* Given:
*   nvec      int       The number of vectors.
*
*   nelem     int       The length of each vector.
*
*   first     const double*
*                       Pointer to the first element to test in the array.
*                       The elements tested for equality are
*
=                         *first == *(first + nelem)
=                                == *(first + nelem*2)
=                                           :
=                                == *(first + nelem*(nvec-1));
*
*                       The array might be dimensioned as
*
=                         double v[nvec][nelem];
*
* Function return value:
*             int       Status return value:
*                         0: Not all equal.
*                         1: All equal.
*
*
* wcsutil_dblEq() - Test for equality of two arrays of type double
* ----------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_dblEq() tests for equality of two double-precision arrays.
*
* Given:
*   nelem     int       The number of elements in each array.
*
*   tol       double    Tolerance for comparison of the floating-point values.
*                       For example, for tol == 1e-6, all floating-point
*                       values in the arrays must be equal to the first 6
*                       decimal places.  A value of 0 implies exact equality.
*
*   arr1      const double*
*                       The first array.
*
*   arr2      const double*
*                       The second array
*
* Function return value:
*             int       Status return value:
*                         0: Not equal.
*                         1: Equal.
*
*
* wcsutil_intEq() - Test for equality of two arrays of type int
* -------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_intEq() tests for equality of two int arrays.
*
* Given:
*   nelem     int       The number of elements in each array.
*
*   arr1      const int*
*                       The first array.
*
*   arr2      const int*
*                       The second array
*
* Function return value:
*             int       Status return value:
*                         0: Not equal.
*                         1: Equal.
*
*
* wcsutil_strEq() - Test for equality of two string arrays
* --------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_strEq() tests for equality of two string arrays.
*
* Given:
*   nelem     int       The number of elements in each array.
*
*   arr1      const char**
*                       The first array.
*
*   arr2      const char**
*                       The second array
*
* Function return value:
*             int       Status return value:
*                         0: Not equal.
*                         1: Equal.
*
*
* wcsutil_setAll() - Set a particular vector element
* --------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_setAll() sets the value of a particular element in a set of vectors
* of type double.
*
* Given:
*   nvec      int       The number of vectors.
*
*   nelem     int       The length of each vector.
*
* Given and returned:
*   first     double*   Pointer to the first element in the array, the value
*                       of which is used to set the others
*
=                         *(first + nelem) = *first;
=                         *(first + nelem*2) = *first;
=                                 :
=                         *(first + nelem*(nvec-1)) = *first;
*
*                       The array might be dimensioned as
*
=                         double v[nvec][nelem];
*
* Function return value:
*             void
*
*
* wcsutil_setAli() - Set a particular vector element
* --------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_setAli() sets the value of a particular element in a set of vectors
* of type int.
*
* Given:
*   nvec      int       The number of vectors.
*
*   nelem     int       The length of each vector.
*
* Given and returned:
*   first     int*      Pointer to the first element in the array, the value
*                       of which is used to set the others
*
=                         *(first + nelem) = *first;
=                         *(first + nelem*2) = *first;
=                                 :
=                         *(first + nelem*(nvec-1)) = *first;
*
*                       The array might be dimensioned as
*
=                         int v[nvec][nelem];
*
* Function return value:
*             void
*
*
* wcsutil_setBit() - Set bits in selected elements of an array
* ------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_setBit() sets bits in selected elements of an array.
*
* Given:
*   nelem     int       Number of elements in the array.
*
*   sel       const int*
*                       Address of a selection array of length nelem.  May
*                       be specified as the null pointer in which case all
*                       elements are selected.
*
*   bits      int       Bit mask.
*
* Given and returned:
*   array     int*      Address of the array of length nelem.
*
* Function return value:
*             void
*
*
* wcsutil_fptr2str() - Translate pointer-to-function to string
* ------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_fptr2str() translates a pointer-to-function to hexadecimal string
* representation for output.  It is used by the various routines that print
* the contents of WCSLIB structs, noting that it is not strictly legal to
* type-pun a function pointer to void*.  See
* http://stackoverflow.com/questions/2741683/how-to-format-a-function-pointer
*
* Given:
*   fptr      void(*)() Pointer to function.
*
* Returned:
*   hext      char[19]  Null-terminated string.  Should be at least 19 bytes
*                       in size to accomodate a 64-bit address (16 bytes in
*                       hex), plus the leading "0x" and trailing '\0'.
*
* Function return value:
*             char *    The address of hext.
*
*
* wcsutil_double2str() - Translate double to string ignoring the locale
* ---------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_double2str() converts a double to a string, but unlike sprintf() it
* ignores the locale and always uses a '.' as the decimal separator.  Also,
* unless it includes an exponent, the formatted value will always have a
* fractional part, ".0" being appended if necessary.
*
* Returned:
*   buf       char *    The buffer to write the string into.
*
* Given:
*   format    char *    The formatting directive, such as "%f".  This
*                       may be any of the forms accepted by sprintf(), but
*                       should only include a formatting directive and
*                       nothing else.  For "%g" and "%G" formats, unless it
*                       includes an exponent, the formatted value will always
*                       have a fractional part, ".0" being appended if
*                       necessary.
*
*   value     double    The value to convert to a string.
*
*
* wcsutil_str2double() - Translate string to a double, ignoring the locale
* ------------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_str2double() converts a string to a double, but unlike sscanf() it
* ignores the locale and always expects a '.' as the decimal separator.
*
* Given:
*   buf       char *    The string containing the value
*
* Returned:
*   value     double *  The double value parsed from the string.
*
*
* wcsutil_str2double2() - Translate string to doubles, ignoring the locale
* ------------------------------------------------------------------------
* INTERNAL USE ONLY.
*
* wcsutil_str2double2() converts a string to a pair of doubles containing the
* integer and fractional parts.  Unlike sscanf() it ignores the locale and
* always expects a '.' as the decimal separator.
*
* Given:
*   buf       char *    The string containing the value
*
* Returned:
*   value     double[2] The double value, split into integer and fractional
*                       parts, parsed from the string.
*
*===========================================================================*/
 
#ifndef WCSLIB_WCSUTIL
#define WCSLIB_WCSUTIL
 
#ifdef __cplusplus
extern "C" {
#endif
 
void wcsdealloc(void *ptr);
 
void wcsutil_strcvt(int n, char c, int nt, const char src[], char dst[]);
 
void wcsutil_blank_fill(int n, char c[]);
void wcsutil_null_fill (int n, char c[]);
 
int  wcsutil_all_ival(int nelem, int ival, const int iarr[]);
int  wcsutil_all_dval(int nelem, double dval, const double darr[]);
int  wcsutil_all_sval(int nelem, const char *sval, const char (*sarr)[72]);
int  wcsutil_allEq (int nvec, int nelem, const double *first);
 
int  wcsutil_dblEq(int nelem, double tol, const double *arr1,
                   const double *arr2);
int  wcsutil_intEq(int nelem, const int *arr1, const int *arr2);
int  wcsutil_strEq(int nelem, char (*arr1)[72], char (*arr2)[72]);
void wcsutil_setAll(int nvec, int nelem, double *first);
void wcsutil_setAli(int nvec, int nelem, int *first);
void wcsutil_setBit(int nelem, const int *sel, int bits, int *array);
char *wcsutil_fptr2str(void (*fptr)(void), char hext[19]);
void wcsutil_double2str(char *buf, const char *format, double value);
int  wcsutil_str2double(const char *buf, double *value);
int  wcsutil_str2double2(const char *buf, double *value);
 
#ifdef __cplusplus
}
#endif
 
#endif // WCSLIB_WCSUTIL