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
|
#
#
# The Nim Compiler
# (c) Copyright 2012 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
## Low-level streams for high performance.
import
strutils, pathutils
# support '-d:useGnuReadline' for backwards compatibility:
when not defined(windows) and (defined(useGnuReadline) or defined(useLinenoise)):
import rdstdin
type
TLLStreamKind* = enum # enum of different stream implementations
llsNone, # null stream: reading and writing has no effect
llsString, # stream encapsulates a string
llsFile, # stream encapsulates a file
llsStdIn # stream encapsulates stdin
TLLStream* = object of RootObj
kind*: TLLStreamKind # accessible for low-level access (lexbase uses this)
f*: File
s*: string
rd*, wr*: int # for string streams
lineOffset*: int # for fake stdin line numbers
PLLStream* = ref TLLStream
proc llStreamOpen*(data: string): PLLStream =
new(result)
result.s = data
result.kind = llsString
proc llStreamOpen*(f: File): PLLStream =
new(result)
result.f = f
result.kind = llsFile
proc llStreamOpen*(filename: AbsoluteFile, mode: FileMode): PLLStream =
new(result)
result.kind = llsFile
if not open(result.f, filename.string, mode): result = nil
proc llStreamOpen*(): PLLStream =
new(result)
result.kind = llsNone
proc llStreamOpenStdIn*(): PLLStream =
new(result)
result.kind = llsStdIn
result.s = ""
result.lineOffset = -1
proc llStreamClose*(s: PLLStream) =
case s.kind
of llsNone, llsString, llsStdIn:
discard
of llsFile:
close(s.f)
when not declared(readLineFromStdin):
# fallback implementation:
proc readLineFromStdin(prompt: string, line: var string): bool =
stdout.write(prompt)
result = readLine(stdin, line)
if not result:
stdout.write("\n")
quit(0)
proc endsWith*(x: string, s: set[char]): bool =
var i = x.len-1
while i >= 0 and x[i] == ' ': dec(i)
if i >= 0 and x[i] in s:
result = true
const
LineContinuationOprs = {'+', '-', '*', '/', '\\', '<', '>', '!', '?', '^',
'|', '%', '&', '$', '@', '~', ','}
AdditionalLineContinuationOprs = {'#', ':', '='}
proc endsWithOpr*(x: string): bool =
result = x.endsWith(LineContinuationOprs)
proc continueLine(line: string, inTripleString: bool): bool {.inline.} =
result = inTripleString or line.len > 0 and (
line[0] == ' ' or
line.endsWith(LineContinuationOprs+AdditionalLineContinuationOprs))
proc countTriples(s: string): int =
var i = 0
while i < s.len:
if s[i] == '"' and s[i+1] == '"' and s[i+2] == '"':
inc result
inc i, 2
inc i
proc llReadFromStdin(s: PLLStream, buf: pointer, bufLen: int): int =
s.s = ""
s.rd = 0
var line = newStringOfCap(120)
var triples = 0
while readLineFromStdin(if s.s.len == 0: ">>> " else: "... ", line):
add(s.s, line)
add(s.s, "\n")
inc triples, countTriples(line)
if not continueLine(line, (triples and 1) == 1): break
inc(s.lineOffset)
result = min(bufLen, len(s.s) - s.rd)
if result > 0:
copyMem(buf, addr(s.s[s.rd]), result)
inc(s.rd, result)
proc llStreamRead*(s: PLLStream, buf: pointer, bufLen: int): int =
case s.kind
of llsNone:
result = 0
of llsString:
result = min(bufLen, len(s.s) - s.rd)
if result > 0:
copyMem(buf, addr(s.s[0 + s.rd]), result)
inc(s.rd, result)
of llsFile:
result = readBuffer(s.f, buf, bufLen)
of llsStdIn:
result = llReadFromStdin(s, buf, bufLen)
proc llStreamReadLine*(s: PLLStream, line: var string): bool =
setLen(line, 0)
case s.kind
of llsNone:
result = true
of llsString:
while s.rd < len(s.s):
case s.s[s.rd]
of '\x0D':
inc(s.rd)
if s.s[s.rd] == '\x0A': inc(s.rd)
break
of '\x0A':
inc(s.rd)
break
else:
add(line, s.s[s.rd])
inc(s.rd)
result = line.len > 0 or s.rd < len(s.s)
of llsFile:
result = readLine(s.f, line)
of llsStdIn:
result = readLine(stdin, line)
proc llStreamWrite*(s: PLLStream, data: string) =
case s.kind
of llsNone, llsStdIn:
discard
of llsString:
add(s.s, data)
inc(s.wr, len(data))
of llsFile:
write(s.f, data)
proc llStreamWriteln*(s: PLLStream, data: string) =
llStreamWrite(s, data)
llStreamWrite(s, "\n")
proc llStreamWrite*(s: PLLStream, data: char) =
var c: char
case s.kind
of llsNone, llsStdIn:
discard
of llsString:
add(s.s, data)
inc(s.wr)
of llsFile:
c = data
discard writeBuffer(s.f, addr(c), sizeof(c))
proc llStreamWrite*(s: PLLStream, buf: pointer, buflen: int) =
case s.kind
of llsNone, llsStdIn:
discard
of llsString:
if buflen > 0:
setLen(s.s, len(s.s) + buflen)
copyMem(addr(s.s[0 + s.wr]), buf, buflen)
inc(s.wr, buflen)
of llsFile:
discard writeBuffer(s.f, buf, buflen)
proc llStreamReadAll*(s: PLLStream): string =
const
bufSize = 2048
case s.kind
of llsNone, llsStdIn:
result = ""
of llsString:
if s.rd == 0: result = s.s
else: result = substr(s.s, s.rd)
s.rd = len(s.s)
of llsFile:
result = newString(bufSize)
var bytes = readBuffer(s.f, addr(result[0]), bufSize)
var i = bytes
while bytes == bufSize:
setLen(result, i + bufSize)
bytes = readBuffer(s.f, addr(result[i + 0]), bufSize)
inc(i, bytes)
setLen(result, i)
|