| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include<wchar.h> |
| |
| #include<stdlib.h> |
| #include<string.h> |
| |
| #include"local.h" |
| |
| /// Performs wide-character string to floating point conversion. |
| template<typename float_type> |
| float_type wcstod(constwchar_t* str,wchar_t** end, float_type strtod_fn(constchar*,char**)){ |
| constwchar_t* original_str= str; |
| while(iswspace(*str)){ |
| str++; |
| } |
| |
| // What's the longest span of the input that might be part of the float? |
| size_t max_len= wcsspn(str, L"-+0123456789.xXeEpP()nNaAiIfFtTyY"); |
| |
| // We know the only valid characters are ASCII, so convert them by brute force. |
| char* ascii_str=newchar[max_len+1]; |
| if(!ascii_str)return float_type(); |
| for(size_t i=0; i< max_len;++i){ |
| ascii_str[i]= str[i]&0xff; |
| } |
| ascii_str[max_len]=0; |
| |
| // Set up a fake FILE that points to those ASCII characters, for `parsefloat`. |
| FILE f; |
| __sfileext fext; |
| _FILEEXT_SETUP(&f,&fext); |
| f._flags= __SRD; |
| f._bf._base= f._p=reinterpret_cast<unsignedchar*>(ascii_str); |
| f._bf._size= f._r= max_len; |
| f._read=[](void*,char*,int){return0;};// aka `eofread`, aka "no more data". |
| f._lb._base=nullptr; |
| |
| // Ask `parsefloat` to look at the same data more carefully. |
| |
| // We can't just do this straight away because we can't construct a suitable FILE* |
| // in the absence of any `fwmemopen` analogous to `fmemopen`. And we don't want to |
| // duplicate the `parsefloat` logic. We also don't want to actually have to have wchar_t |
| // implementations of the ASCII `strtod` logic (though if you were designing a libc |
| // from scratch, you'd probably want to just make that more generic and lose all the |
| // cruft on top). |
| size_t actual_len= parsefloat(&f, ascii_str, ascii_str+ max_len); |
| |
| // Finally let the ASCII conversion function do the work. |
| char* ascii_end; |
| float_type result= strtod_fn(ascii_str,&ascii_end); |
| if(ascii_end!= ascii_str+ actual_len) abort(); |
| |
| if(end){ |
| if(actual_len==0){ |
| // There was an error. We need to set the end pointer back to the original string, not the |
| // one we advanced past the leading whitespace. |
| *end=const_cast<wchar_t*>(original_str); |
| }else{ |
| *end=const_cast<wchar_t*>(str)+ actual_len; |
| } |
| } |
| |
| delete[] ascii_str; |
| return result; |
| } |
| |
| float wcstof(constwchar_t* s,wchar_t** end){ |
| return wcstod<float>(s, end, strtof); |
| } |
| __strong_alias(wcstof_l, wcstof); |
| |
| double wcstod(constwchar_t* s,wchar_t** end){ |
| return wcstod<double>(s, end, strtod); |
| } |
| __strong_alias(wcstod_l, wcstod); |
| |
| longdouble wcstold(constwchar_t* s,wchar_t** end){ |
| return wcstod<longdouble>(s, end, strtold); |
| } |
| __strong_alias(wcstold_l, wcstold); |
