1// Copyright 2014 PDFium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7#include "../../include/fxcrt/fx_basic.h"
8void CFX_UTF8Decoder::Clear()
9{
10    m_Buffer.Clear();
11    m_PendingBytes = 0;
12}
13void CFX_UTF8Decoder::AppendChar(FX_DWORD ch)
14{
15    m_Buffer.AppendChar((FX_WCHAR)ch);
16}
17void CFX_UTF8Decoder::Input(FX_BYTE byte)
18{
19    if (byte < 0x80) {
20        m_PendingBytes = 0;
21        m_Buffer.AppendChar(byte);
22    } else if (byte < 0xc0) {
23        if (m_PendingBytes == 0) {
24            return;
25        }
26        m_PendingBytes --;
27        m_PendingChar |= (byte & 0x3f) << (m_PendingBytes * 6);
28        if (m_PendingBytes == 0) {
29            AppendChar(m_PendingChar);
30        }
31    } else if (byte < 0xe0) {
32        m_PendingBytes = 1;
33        m_PendingChar = (byte & 0x1f) << 6;
34    } else if (byte < 0xf0) {
35        m_PendingBytes = 2;
36        m_PendingChar = (byte & 0x0f) << 12;
37    } else if (byte < 0xf8) {
38        m_PendingBytes = 3;
39        m_PendingChar = (byte & 0x07) << 18;
40    } else if (byte < 0xfc) {
41        m_PendingBytes = 4;
42        m_PendingChar = (byte & 0x03) << 24;
43    } else if (byte < 0xfe) {
44        m_PendingBytes = 5;
45        m_PendingChar = (byte & 0x01) << 30;
46    }
47}
48void CFX_UTF8Encoder::Input(FX_WCHAR unicode)
49{
50    if ((FX_DWORD)unicode < 0x80) {
51        m_Buffer.AppendChar(unicode);
52    } else {
53        if ((FX_DWORD)unicode >= 0x80000000) {
54            return;
55        }
56        int nbytes = 0;
57        if ((FX_DWORD)unicode < 0x800) {
58            nbytes = 2;
59        } else if ((FX_DWORD)unicode < 0x10000) {
60            nbytes = 3;
61        } else if ((FX_DWORD)unicode < 0x200000) {
62            nbytes = 4;
63        } else if ((FX_DWORD)unicode < 0x4000000) {
64            nbytes = 5;
65        } else {
66            nbytes = 6;
67        }
68        static FX_BYTE prefix[] = {0xc0, 0xe0, 0xf0, 0xf8, 0xfc};
69        int order = 1 << ((nbytes - 1) * 6);
70        int code = unicode;
71        m_Buffer.AppendChar(prefix[nbytes - 2] | (code / order));
72        for (int i = 0; i < nbytes - 1; i ++) {
73            code = code % order;
74            order >>= 6;
75            m_Buffer.AppendChar(0x80 | (code / order));
76        }
77    }
78}
79CFX_ByteString FX_UTF8Encode(FX_LPCWSTR pwsStr, FX_STRSIZE len)
80{
81    FXSYS_assert(pwsStr != NULL);
82    if (len < 0) {
83        len = (FX_STRSIZE)FXSYS_wcslen(pwsStr);
84    }
85    CFX_UTF8Encoder encoder;
86    while (len -- > 0) {
87        encoder.Input(*pwsStr ++);
88    }
89    return encoder.GetResult();
90}
91void FX_UTF8Encode(FX_LPCWSTR pwsStr, FX_STRSIZE len, CFX_ByteStringL &utf8Str, IFX_Allocator* pAllocator)
92{
93    FXSYS_assert(pwsStr != NULL);
94    if (len < 0) {
95        len = (FX_STRSIZE)FXSYS_wcslen(pwsStr);
96    }
97    CFX_UTF8Encoder encoder(pAllocator);
98    while (len -- > 0) {
99        encoder.Input(*pwsStr ++);
100    }
101    encoder.GetResult(utf8Str);
102}
103