| /* |
| * Copyright (C) 2014 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<assert.h> |
| #include<errno.h> |
| #include<uchar.h> |
| #include<wchar.h> |
| |
| #include"private/bionic_mbstate.h" |
| |
| staticinlinebool mbspartialc16(constmbstate_t* state){ |
| return mbstate_get_byte(state,3)!=0; |
| } |
| |
| staticsize_t begin_surrogate(char32_t c32,char16_t* pc16, |
| size_t nconv,mbstate_t* state){ |
| c32-=0x10000; |
| char16_t trail=(c32&0x3ff)|0xdc00; |
| |
| mbstate_set_byte(state,0, trail&0x00ff); |
| mbstate_set_byte(state,1,(trail&0xff00)>>8); |
| mbstate_set_byte(state,3, nconv&0xff); |
| |
| *pc16=((c32&0xffc00)>>10)|0xd800; |
| // https://issuetracker.google.com/289419882 |
| // |
| // We misread the spec when implementing this. The first call should return |
| // the length of the decoded character, and the second call should return -3 |
| // to indicate that the output is a continuation of the character decoded by |
| // the first call. |
| // |
| // C23 7.30.1.3.4: |
| // |
| // between 1 and n inclusive if the next n or fewer bytes complete a valid |
| // multibyte character (which is the value stored); the value returned is |
| // the number of bytes that complete the multibyte character. |
| // |
| // (size_t)(-3) if the next character resulting from a previous call has |
| // been stored (no bytes from the input have been consumed by this call). |
| // |
| // The first call returns the number of bytes consumed, and the second call |
| // returns -3. |
| // |
| // All UTF-8 sequences that encode a surrogate pair are 4 bytes, but we may |
| // not have seen the full sequence yet. |
| return nconv; |
| } |
| |
| staticsize_t finish_surrogate(char16_t* pc16,mbstate_t* state){ |
| char16_t trail= mbstate_get_byte(state,1)<<8| |
| mbstate_get_byte(state,0); |
| *pc16= trail; |
| mbstate_reset(state); |
| returnstatic_cast<size_t>(-3); |
| } |
| |
| size_t mbrtoc16(char16_t* pc16,constchar* s,size_t n,mbstate_t* ps){ |
| staticmbstate_t __private_state; |
| mbstate_t* state=(ps==nullptr)?&__private_state: ps; |
| |
| char16_t __private_pc16; |
| if(pc16==nullptr){ |
| pc16=&__private_pc16; |
| } |
| |
| if(mbspartialc16(state)){ |
| return finish_surrogate(pc16, state); |
| } |
| |
| char32_t c32; |
| size_t nconv= mbrtoc32(&c32, s, n, state); |
| if(__MB_IS_ERR(nconv)){ |
| return nconv; |
| }elseif(nconv==0){ |
| return mbstate_reset_and_return(nconv, state); |
| }elseif(c32<0x10000){ |
| *pc16=static_cast<char16_t>(c32); |
| return mbstate_reset_and_return(nconv, state); |
| }elseif(c32>0x10ffff){ |
| // This case is currently handled by mbrtoc32() returning an error, but |
| // if that function is extended to cover 5-byte sequences (which are |
| // illegal at the moment), we'd need to explicitly handle the case of |
| // codepoints that can't be represented as a surrogate pair here. |
| return mbstate_reset_and_return_illegal(EILSEQ, state); |
| }else{ |
| return begin_surrogate(c32, pc16, nconv, state); |
| } |
| } |
