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
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
|
var events = require("events"),
util = require("../util");
function Packet(type, size) {
this.type = type;
this.size = +size;
}
exports.name = "javascript";
exports.debug_mode = false;
function ReplyParser(options) {
this.name = exports.name;
this.options = options || { };
this._buffer = null;
this._offset = 0;
this._encoding = "utf-8";
this._debug_mode = options.debug_mode;
this._reply_type = null;
}
util.inherits(ReplyParser, events.EventEmitter);
exports.Parser = ReplyParser;
function IncompleteReadBuffer(message) {
this.name = "IncompleteReadBuffer";
this.message = message;
}
util.inherits(IncompleteReadBuffer, Error);
// Buffer.toString() is quite slow for small strings
function small_toString(buf, start, end) {
var tmp = "", i;
for (i = start; i < end; i++) {
tmp += String.fromCharCode(buf[i]);
}
return tmp;
}
ReplyParser.prototype._parseResult = function (type) {
var start, end, offset, packetHeader;
if (type === 43 || type === 45) { // + or -
// up to the delimiter
end = this._packetEndOffset() - 1;
start = this._offset;
// include the delimiter
this._offset = end + 2;
if (end > this._buffer.length) {
this._offset = start;
throw new IncompleteReadBuffer("Wait for more data.");
}
if (this.options.return_buffers) {
return this._buffer.slice(start, end);
} else {
if (end - start < 65536) { // completely arbitrary
return small_toString(this._buffer, start, end);
} else {
return this._buffer.toString(this._encoding, start, end);
}
}
} else if (type === 58) { // :
// up to the delimiter
end = this._packetEndOffset() - 1;
start = this._offset;
// include the delimiter
this._offset = end + 2;
if (end > this._buffer.length) {
this._offset = start;
throw new IncompleteReadBuffer("Wait for more data.");
}
if (this.options.return_buffers) {
return this._buffer.slice(start, end);
}
// return the coerced numeric value
return +small_toString(this._buffer, start, end);
} else if (type === 36) { // $
// set a rewind point, as the packet could be larger than the
// buffer in memory
offset = this._offset - 1;
packetHeader = new Packet(type, this.parseHeader());
// packets with a size of -1 are considered null
if (packetHeader.size === -1) {
return undefined;
}
end = this._offset + packetHeader.size;
start = this._offset;
// set the offset to after the delimiter
this._offset = end + 2;
if (end > this._buffer.length) {
this._offset = offset;
throw new IncompleteReadBuffer("Wait for more data.");
}
if (this.options.return_buffers) {
return this._buffer.slice(start, end);
} else {
return this._buffer.toString(this._encoding, start, end);
}
} else if (type === 42) { // *
offset = this._offset;
packetHeader = new Packet(type, this.parseHeader());
if (packetHeader.size < 0) {
return null;
}
if (packetHeader.size > this._bytesRemaining()) {
this._offset = offset - 1;
throw new IncompleteReadBuffer("Wait for more data.");
}
var reply = [ ];
var ntype, i, res;
offset = this._offset - 1;
for (i = 0; i < packetHeader.size; i++) {
ntype = this._buffer[this._offset++];
if (this._offset > this._buffer.length) {
throw new IncompleteReadBuffer("Wait for more data.");
}
res = this._parseResult(ntype);
if (res === undefined) {
res = null;
}
reply.push(res);
}
return reply;
}
};
ReplyParser.prototype.execute = function (buffer) {
this.append(buffer);
var type, ret, offset;
while (true) {
offset = this._offset;
try {
// at least 4 bytes: :1\r\n
if (this._bytesRemaining() < 4) {
break;
}
type = this._buffer[this._offset++];
if (type === 43) { // +
ret = this._parseResult(type);
if (ret === null) {
break;
}
this.send_reply(ret);
} else if (type === 45) { // -
ret = this._parseResult(type);
if (ret === null) {
break;
}
this.send_error(ret);
} else if (type === 58) { // :
ret = this._parseResult(type);
if (ret === null) {
break;
}
this.send_reply(ret);
} else if (type === 36) { // $
ret = this._parseResult(type);
if (ret === null) {
break;
}
// check the state for what is the result of
// a -1, set it back up for a null reply
if (ret === undefined) {
ret = null;
}
this.send_reply(ret);
} else if (type === 42) { // *
// set a rewind point. if a failure occurs,
// wait for the next execute()/append() and try again
offset = this._offset - 1;
ret = this._parseResult(type);
this.send_reply(ret);
}
} catch (err) {
// catch the error (not enough data), rewind, and wait
// for the next packet to appear
if (! (err instanceof IncompleteReadBuffer)) {
throw err;
}
this._offset = offset;
break;
}
}
};
ReplyParser.prototype.append = function (newBuffer) {
if (!newBuffer) {
return;
}
// first run
if (this._buffer === null) {
this._buffer = newBuffer;
return;
}
// out of data
if (this._offset >= this._buffer.length) {
this._buffer = newBuffer;
this._offset = 0;
return;
}
// very large packet
// check for concat, if we have it, use it
if (Buffer.concat !== undefined) {
this._buffer = Buffer.concat([this._buffer.slice(this._offset), newBuffer]);
} else {
var remaining = this._bytesRemaining(),
newLength = remaining + newBuffer.length,
tmpBuffer = new Buffer(newLength);
this._buffer.copy(tmpBuffer, 0, this._offset);
newBuffer.copy(tmpBuffer, remaining, 0);
this._buffer = tmpBuffer;
}
this._offset = 0;
};
ReplyParser.prototype.parseHeader = function () {
var end = this._packetEndOffset(),
value = small_toString(this._buffer, this._offset, end - 1);
this._offset = end + 1;
return value;
};
ReplyParser.prototype._packetEndOffset = function () {
var offset = this._offset;
while (this._buffer[offset] !== 0x0d && this._buffer[offset + 1] !== 0x0a) {
offset++;
if (offset >= this._buffer.length) {
throw new IncompleteReadBuffer("didn't see LF after NL reading multi bulk count (" + offset + " => " + this._buffer.length + ", " + this._offset + ")");
}
}
offset++;
return offset;
};
ReplyParser.prototype._bytesRemaining = function () {
return (this._buffer.length - this._offset) < 0 ? 0 : (this._buffer.length - this._offset);
};
ReplyParser.prototype.parser_error = function (message) {
this.emit("error", message);
};
ReplyParser.prototype.send_error = function (reply) {
this.emit("reply error", reply);
};
ReplyParser.prototype.send_reply = function (reply) {
this.emit("reply", reply);
};
|
