1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
|
package java.io
import scala.scalajs.js.typedarray._
class DataInputStream(in: InputStream) extends FilterInputStream(in)
with DataInput {
private var pushedBack: Int = -1
private var pushedBackMark: Int = -1
// -- ArrayBufferInputStream mode helpers --
// These variables are used to special case on ArrayBufferInputStreams
// They allow directly accessing the underlying ArrayBuffer rather than
// creating byte arrays first
private val inArrayBufferStream = in match {
case in: ArrayBufferInputStream => in
case _ => null
}
private val hasArrayBuffer = inArrayBufferStream != null
private val bufDataView = {
if (hasArrayBuffer) {
val in = inArrayBufferStream
new DataView(in.buffer, in.offset, in.length)
} else null
}
private def consumePos(n: Int) = {
val off = if (pushedBack != -1) 1 else 0
val resultPos = inArrayBufferStream.pos - off
val toSkip = n - off
if (in.skip(toSkip) != toSkip) eof()
resultPos
}
// -- General InputStream mode helpers --
// Due to the method readLine, we need to be able to push back a byte (if we
// read a \r and the following byte is NOT a \n). We implement this here.
// We also provide a method to create an ad-hoc data view of the next n bytes
private val convBufLen = 8
private val convBuf = new ArrayBuffer(convBufLen)
private val convInView = new Int8Array(convBuf)
private val convOutView = new DataView(convBuf)
private def view(len: Int) = {
assert(len <= convBufLen)
var i = 0
while (i < len) {
val byte = read()
if (byte == -1) eof()
convInView(i) = byte.toByte
i += 1
}
convOutView
}
// General Helpers
private def eof() = throw new EOFException()
private def pushBack(v: Int) = { pushedBack = v }
// Methods on DataInput
def readBoolean(): Boolean = readByte() != 0
def readByte(): Byte = {
val res = read()
if (res == -1) eof()
res.toByte
}
def readChar(): Char = {
if (hasArrayBuffer)
bufDataView.getUint16(consumePos(2)).toChar
else
view(2).getUint16(0).toChar
}
def readDouble(): Double = {
if (hasArrayBuffer)
bufDataView.getFloat64(consumePos(8))
else
view(8).getFloat64(0)
}
def readFloat(): Float = {
if (hasArrayBuffer)
bufDataView.getFloat32(consumePos(4))
else
view(4).getFloat32(0)
}
def readFully(b: Array[Byte]): Unit = readFully(b, 0, b.length)
def readFully(b: Array[Byte], off: Int, len: Int): Unit = {
if (off < 0 || len < 0 || off + len > b.length)
throw new IndexOutOfBoundsException()
var remaining = len
var offset = off
while (remaining > 0) {
val readCount = read(b, offset, remaining)
if (readCount == -1) eof()
remaining -= readCount
offset += readCount
}
}
def readInt(): Int = {
if (hasArrayBuffer)
bufDataView.getInt32(consumePos(4))
else
view(4).getInt32(0)
}
def readLine(): String = {
var cur = read()
if (cur == -1) null
else {
var res = ""
while (cur != -1 && cur != '\n' && cur != '\r') {
res += cur.toChar
cur = read()
}
if (cur == '\r') {
// Discard a potential \n (from \r\n line endings)
cur = read()
if (cur != '\n') pushBack(cur)
}
res
}
}
def readLong(): Long = {
val hi = readInt().toLong
val lo = readInt().toLong
(hi << 32) | (lo & 0xFFFFFFFFL)
}
def readShort(): Short = {
if (hasArrayBuffer)
bufDataView.getInt16(consumePos(2))
else
view(2).getInt16(0)
}
def readUnsignedByte(): Int = {
val res = read()
if (res == -1) eof()
res
}
def readUnsignedShort(): Int = {
if (hasArrayBuffer)
bufDataView.getUint16(consumePos(2))
else
view(2).getUint16(0)
}
def readUTF(): String = {
val length = readShort()
var res = ""
var i = 0
def badFormat(msg: String) = throw new UTFDataFormatException(msg)
while (i < length) {
val a = read()
if (a == -1)
badFormat(s"Unexpected EOF: ${length - i} bytes to go")
i += 1
val char = {
if ((a & 0x80) == 0x00) { // 0xxxxxxx
a.toChar
} else if ((a & 0xE0) == 0xC0 && i < length) { // 110xxxxx
val b = read()
i += 1
if (b == -1)
badFormat(f"Expected 2 bytes, found: EOF (init: $a%#02x)")
if ((b & 0xC0) != 0x80) // 10xxxxxx
badFormat(f"Expected 2 bytes, found: $b%#02x (init: $a%#02x)")
(((a & 0x1F) << 6) | (b & 0x3F)).toChar
} else if ((a & 0xF0) == 0xE0 && i < length - 1) { // 1110xxxx
val b = read()
val c = read()
i += 2
if (b == -1)
badFormat(f"Expected 3 bytes, found: EOF (init: $a%#02x)")
if ((b & 0xC0) != 0x80) // 10xxxxxx
badFormat(f"Expected 3 bytes, found: $b%#02x (init: $a%#02x)")
if (c == -1)
badFormat(f"Expected 3 bytes, found: $b%#02x, EOF (init: $a%#02x)")
if ((c & 0xC0) != 0x80) // 10xxxxxx
badFormat(
f"Expected 3 bytes, found: $b%#02x, $c%#02x (init: $a%#02x)")
(((a & 0x0F) << 12) | ((b & 0x3F) << 6) | (c & 0x3F)).toChar
} else {
val rem = length - i
badFormat(f"Unexpected start of char: $a%#02x ($rem%d bytes to go)")
}
}
res += char
}
res
}
def skipBytes(n: Int): Int = skip(n.toLong).toInt
// Methods on FilterInputStream.
// Overridden to track pushedBack / pushedBackMark
override def available(): Int = {
if (pushedBack != -1) in.available + 1
else in.available
}
override def mark(readlimit: Int): Unit = {
in.mark(readlimit + 1) // we need one more since we might read ahead
pushedBackMark = pushedBack
}
override def markSupported(): Boolean = in.markSupported()
override def read(): Int = {
val res = {
if (pushedBack != -1)
pushedBack
else
in.read()
}
pushedBack = -1
res
}
override def read(b: Array[Byte], off: Int, len: Int): Int = {
if (len == 0)
0
else if (pushedBack != -1) {
b(off) = pushedBack.toByte
pushedBack = -1
1
} else {
val count = in.read(b, off, len)
count
}
}
override def reset(): Unit = {
in.reset()
pushedBack = pushedBackMark
}
override def skip(n: Long): Long = {
if (n == 0)
0L
else if (pushedBack != -1) {
pushedBack = -1
1L
} else {
val skipped = in.skip(n)
skipped
}
}
}
|