1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <assert.h> 30 #include <errno.h> 31 #include <uchar.h> 32 #include <wchar.h> 33 34 #include "private/bionic_mbstate.h" 35 36 static inline bool mbspartialc16(const mbstate_t* state) { 37 return mbstate_get_byte(state, 3) != 0; 38 } 39 40 static size_t begin_surrogate(char32_t c32, char16_t* pc16, 41 size_t nconv, mbstate_t* state) { 42 c32 -= 0x10000; 43 char16_t trail = (c32 & 0x3ff) | 0xdc00; 44 45 mbstate_set_byte(state, 0, trail & 0x00ff); 46 mbstate_set_byte(state, 1, (trail & 0xff00) >> 8); 47 mbstate_set_byte(state, 3, nconv & 0xff); 48 49 *pc16 = ((c32 & 0xffc00) >> 10) | 0xd800; 50 // Defined by POSIX as return value for first surrogate character. 51 return static_cast<size_t>(-3); 52 } 53 54 static size_t finish_surrogate(char16_t* pc16, mbstate_t* state) { 55 char16_t trail = mbstate_get_byte(state, 1) << 8 | 56 mbstate_get_byte(state, 0); 57 *pc16 = trail; 58 return mbstate_reset_and_return(mbstate_get_byte(state, 3), state); 59 } 60 61 size_t mbrtoc16(char16_t* pc16, const char* s, size_t n, mbstate_t* ps) { 62 static mbstate_t __private_state; 63 mbstate_t* state = (ps == NULL) ? &__private_state : ps; 64 65 char16_t __private_pc16; 66 if (pc16 == NULL) { 67 pc16 = &__private_pc16; 68 } 69 70 if (mbspartialc16(state)) { 71 return finish_surrogate(pc16, state); 72 } 73 74 char32_t c32; 75 size_t nconv = mbrtoc32(&c32, s, n, state); 76 if (__MB_IS_ERR(nconv)) { 77 return nconv; 78 } else if (nconv == 0) { 79 return mbstate_reset_and_return(nconv, state); 80 } else if (c32 > 0x10ffff) { 81 // Input cannot be encoded as UTF-16. 82 return mbstate_reset_and_return_illegal(EILSEQ, state); 83 } else if (c32 < 0x10000) { 84 *pc16 = static_cast<char16_t>(c32); 85 return mbstate_reset_and_return(nconv, state); 86 } else { 87 return begin_surrogate(c32, pc16, nconv, state); 88 } 89 } 90
