--- /dev/null
+/*
+ * wcstofp.c
+ *
+ * Implementation of ISO-C99 compatible wcstod(), wcstold(), and wcstof()
+ * functions, placed into the "__mingw_" pseudo-namespace, with enhanced
+ * C99 compatibility, and codeset coverage.
+ *
+ *
+ * $Id$
+ *
+ * Written by Keith Marshall <keith@users.osdn.me>
+ * Copyright (C) 2020, MinGW.org Project
+ *
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice, this permission notice, and the following
+ * disclaimer shall be included in all copies or substantial portions of
+ * the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OF OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ *
+ * Compile with "-D FUNCTION=wcstod -o wcstod.o", or equivalent for each
+ * of wcstold() and wcstof(), to create free-standing object modules for
+ * each supported function; additionally, compile without "-D FUNCTION",
+ * and with "-o wcstofp.o", (or with "-D FUNCTION=wcstofp -o wcstofp.o"),
+ * to create the mandatory common supporting object code module.
+ *
+ */
+#define _ISOC99_SOURCE
+
+/* Parsing of floating point values, from wchar_t strings, is performed
+ * after conversion to the MBCS domain; to support any codeset with more
+ * than two bytes per code point, we require MinGW.org's extended codeset
+ * mapping API.
+ */
+#include "wcharmap.h"
+
+/* Declare prototypes, visible within each derived compilation unit, for
+ * each supporting function which is to be compiled into the common unit.
+ */
+const wchar_t *__mingw_wcstofp_prescan( const wchar_t * );
+size_t __mingw_wcstofp_prepare( const wchar_t *, char *, size_t );
+size_t __mingw_wcstofp_bufsize( const wchar_t * );
+
+/* Ensure that the function to be compiled has been specified...
+ */
+#ifndef FUNCTION
+/* ...or alternatively, fall back to compilation of the common "wcstofp"
+ * support code module...
+ */
+#define FUNCTION wcstofp
+#endif
+/* ...and define a symbolic selector for the latter.
+ */
+#define wcstofp 1
+
+#if FUNCTION
+/* Default FUNCTION assignment -- compile the core support routines,
+ * common to all public API entry points.
+ */
+const wchar_t *__mingw_wcstofp_prescan( const wchar_t *nptr )
+{
+ /* Helper function to locate the effective starting point of a wchar_t
+ * string, ignoring any leading white-space.
+ */
+ if( nptr == NULL ) errno = EINVAL;
+ else while( iswspace( *nptr ) ) ++nptr;
+ return nptr;
+}
+
+size_t __mingw_wcstofp_prepare ( const wchar_t *nptr, char *mbs, size_t max )
+{
+ /* Helper function to prepare for interpretation of a wchar_t string
+ * representation of a floating point number; determines the size of
+ * buffer required, and optionally converts to MBCS representation,
+ * for interpretation by an apropriate string to binary converter.
+ */
+ size_t nbytes = (size_t)(0);
+ while( *nptr != L'\0' )
+ { /* Excluding the terminating NUL, convert wchar_t string elements
+ * one by one...
+ */
+ size_t count = __mingw_wctomb_convert( mbs, max, nptr++, 1 );
+
+ /* ...and, for each successfully converted, without exceeding the
+ * specified maximum conversion buffer length...
+ */
+ if( count != (size_t)(-1) )
+ { /* ...optionally store its MBCS equivalent, while unconditionally
+ * the actual buffer length requirement...
+ */
+ if( mbs != NULL ) { mbs += count; max -= count; }
+ nbytes += count;
+ }
+ /* Bail out early, if any element cannot be converted successfully,
+ * returning the count of MBCS bytes up to point of failure...
+ */
+ else return nbytes;
+ }
+ /* ...or similarly, the count of MBCS bytes for complete conversion,
+ * when the entire wchar_t string can be successfully converted.
+ */
+ return nbytes;
+}
+
+/* A wrapper around the preceding function, to determine the required
+ * buffer size, without storing the MBCS conversion; used by callers,
+ * to allocate buffers of suitable size.
+ */
+size_t __mingw_wcstofp_bufsize( const wchar_t *nptr )
+{ return 1 + __mingw_wcstofp_prepare( nptr, NULL, 0 ); }
+
+#else
+/* Compile function code for one specific public API entry point.
+ */
+#undef wcstod
+#undef wcstold
+#undef wcstof
+
+/* Define macros to specify the one specific entry point name...
+ */
+#define __mingw_redirect(FUNCTION) set(__mingw,FUNCTION)
+
+/* ...and the associated data type, initial value, and corresponding
+ * MBCS string to binary conversion function name.
+ */
+#define set(FUNCTION,NAME) FUNCTION##_##NAME
+#define datatype(FUNCTION) set(FUNCTION,datatype)
+#define initval(FUNCTION) set(FUNCTION,initval)
+#define strtofp(FUNCTION) set(FUNCTION,strtofp)
+
+/* Specify MBCS converter, data type, and initial value for the
+ * __mingw_wcstod() function.
+ */
+#define wcstod_strtofp strtod
+#define wcstod_datatype double
+#define wcstod_initval 0.0
+
+/* Likewise, for the __mingw_wcstold() function...
+ */
+#define wcstold_strtofp strtold
+#define wcstold_datatype long double
+#define wcstold_initval 0.0L
+
+/* ...and the __mingw_wcstof() function.
+ */
+#define wcstof_strtofp strtof
+#define wcstof_datatype float
+#define wcstof_initval 0.0F
+
+/* Generic API function implementation, in terms of the above.
+ */
+datatype(FUNCTION) __mingw_redirect(FUNCTION)
+( const wchar_t *restrict nptr, wchar_t **restrict endptr )
+{
+ /* Initialize, to return appropriately typed zero, in the event
+ * of no valid floating point representation being found.
+ */
+ datatype(FUNCTION) retval = initval(FUNCTION);
+
+ /* Advance the wchar_t string pointer, beyond any white-space
+ * characters which may be present.
+ */
+ if( (nptr = __mingw_wcstofp_prescan( nptr )) != NULL )
+ {
+ /* We found a candidate wchar_t string for interpretation;
+ * allocate buffer space, for conversion to an MBCS string,
+ * with respect to the codeset for the current locale.
+ */
+ size_t buflen;
+ (void)(__mingw_wctomb_codeset_init());
+ if( (buflen = __mingw_wcstofp_bufsize( nptr )) > 0 )
+ { char mbstr[buflen], *endmark;
+
+ /* Convert to MBCS, appending NUL terminator, and attempt
+ * equivalent binary floating point interpretation.
+ */
+ mbstr[__mingw_wcstofp_prepare( nptr, mbstr, buflen )] = '\0';
+ retval = strtofp(FUNCTION)( mbstr, &endmark );
+
+ if( endptr != NULL )
+ { /* Caller wants to check for any junk, following the
+ * numeric representation within the original wchar_t
+ * string, but we know only the corresponding offset
+ * of trailing junk within the MBCS string; step along
+ * the wchar_t string, converting one element at a time,
+ * until the aggregate conversion length matches the
+ * known MBCS junk offset.
+ */
+ char *p = mbstr;
+ while( p < endmark )
+ p += __mingw_wctomb_convert( NULL, 0, nptr++, 1 );
+ *endptr = (wchar_t *)(nptr);
+ }
+ }
+ }
+ /* Return the floating point result, whether it was interpreted
+ * from the given wchar_t string, or remains as initial default.
+ */
+ return retval;
+}
+
+/* Microsoft's runtime library provides its own implementation for
+ * wcstod(), but (prior to non-free MSVCR120.DLL) not for wcstof(),
+ * or wcstold(); request creation of aliases for the latter pair...
+ */
+#define wcstof 1
+#define wcstold 1
+
+#if FUNCTION
+/* ...then implement macros...
+ */
+#define stringify(NAME) #NAME
+#define mkstring(NAME) stringify(NAME)
+
+/* ...avoiding substitution of the function names...
+ */
+#undef wcstof
+#undef wcstold
+
+/* ...to actually implement these aliases.
+ */
+datatype(FUNCTION)
+__attribute__((__weak__,__alias__(mkstring(__mingw_redirect(FUNCTION)))))
+FUNCTION ( const wchar_t *restrict nptr, wchar_t **restrict endptr );
+
+#endif
+#endif
+
+/* $RCSfile$: end of file */
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