1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "utf.h"
18
19#include "base/logging.h"
20#include "mirror/array.h"
21#include "mirror/object-inl.h"
22
23namespace art {
24
25size_t CountModifiedUtf8Chars(const char* utf8) {
26  size_t len = 0;
27  int ic;
28  while ((ic = *utf8++) != '\0') {
29    len++;
30    if ((ic & 0x80) == 0) {
31      // one-byte encoding
32      continue;
33    }
34    // two- or three-byte encoding
35    utf8++;
36    if ((ic & 0x20) == 0) {
37      // two-byte encoding
38      continue;
39    }
40    // three-byte encoding
41    utf8++;
42  }
43  return len;
44}
45
46void ConvertModifiedUtf8ToUtf16(uint16_t* utf16_data_out, const char* utf8_data_in) {
47  while (*utf8_data_in != '\0') {
48    *utf16_data_out++ = GetUtf16FromUtf8(&utf8_data_in);
49  }
50}
51
52void ConvertUtf16ToModifiedUtf8(char* utf8_out, const uint16_t* utf16_in, size_t char_count) {
53  while (char_count--) {
54    uint16_t ch = *utf16_in++;
55    if (ch > 0 && ch <= 0x7f) {
56      *utf8_out++ = ch;
57    } else {
58      if (ch > 0x07ff) {
59        *utf8_out++ = (ch >> 12) | 0xe0;
60        *utf8_out++ = ((ch >> 6) & 0x3f) | 0x80;
61        *utf8_out++ = (ch & 0x3f) | 0x80;
62      } else /*(ch > 0x7f || ch == 0)*/ {
63        *utf8_out++ = (ch >> 6) | 0xc0;
64        *utf8_out++ = (ch & 0x3f) | 0x80;
65      }
66    }
67  }
68}
69
70int32_t ComputeUtf16Hash(const mirror::CharArray* chars, int32_t offset,
71                         size_t char_count) {
72  int32_t hash = 0;
73  for (size_t i = 0; i < char_count; i++) {
74    hash = hash * 31 + chars->Get(offset + i);
75  }
76  return hash;
77}
78
79int32_t ComputeUtf16Hash(const uint16_t* chars, size_t char_count) {
80  int32_t hash = 0;
81  while (char_count--) {
82    hash = hash * 31 + *chars++;
83  }
84  return hash;
85}
86
87
88uint16_t GetUtf16FromUtf8(const char** utf8_data_in) {
89  uint8_t one = *(*utf8_data_in)++;
90  if ((one & 0x80) == 0) {
91    // one-byte encoding
92    return one;
93  }
94  // two- or three-byte encoding
95  uint8_t two = *(*utf8_data_in)++;
96  if ((one & 0x20) == 0) {
97    // two-byte encoding
98    return ((one & 0x1f) << 6) | (two & 0x3f);
99  }
100  // three-byte encoding
101  uint8_t three = *(*utf8_data_in)++;
102  return ((one & 0x0f) << 12) | ((two & 0x3f) << 6) | (three & 0x3f);
103}
104
105int CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues(const char* utf8_1, const char* utf8_2) {
106  for (;;) {
107    if (*utf8_1 == '\0') {
108      return (*utf8_2 == '\0') ? 0 : -1;
109    } else if (*utf8_2 == '\0') {
110      return 1;
111    }
112
113    int c1 = GetUtf16FromUtf8(&utf8_1);
114    int c2 = GetUtf16FromUtf8(&utf8_2);
115
116    if (c1 != c2) {
117      return c1 > c2 ? 1 : -1;
118    }
119  }
120}
121
122int CompareModifiedUtf8ToUtf16AsCodePointValues(const char* utf8_1, const uint16_t* utf8_2) {
123  for (;;) {
124    if (*utf8_1 == '\0') {
125      return (*utf8_2 == '\0') ? 0 : -1;
126    } else if (*utf8_2 == '\0') {
127      return 1;
128    }
129
130    int c1 = GetUtf16FromUtf8(&utf8_1);
131    int c2 = *utf8_2;
132
133    if (c1 != c2) {
134      return c1 > c2 ? 1 : -1;
135    }
136  }
137}
138
139size_t CountUtf8Bytes(const uint16_t* chars, size_t char_count) {
140  size_t result = 0;
141  while (char_count--) {
142    uint16_t ch = *chars++;
143    if (ch > 0 && ch <= 0x7f) {
144      ++result;
145    } else {
146      if (ch > 0x7ff) {
147        result += 3;
148      } else {
149        result += 2;
150      }
151    }
152  }
153  return result;
154}
155
156}  // namespace art
157