-
-
Notifications
You must be signed in to change notification settings - Fork 5.5k
/
iobuffer.jl
669 lines (596 loc) · 22.7 KB
/
iobuffer.jl
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
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
# This file is a part of Julia. License is MIT: https://julialang.org/license
## work with AbstractVector{UInt8} via I/O primitives ##
# Stateful string
mutable struct GenericIOBuffer{T<:AbstractVector{UInt8}} <: IO
data::T # T should support: getindex, setindex!, length, copyto!, similar, and (optionally) resize!
reinit::Bool # if true, data needs to be re-allocated (after take!)
readable::Bool
writable::Bool
seekable::Bool # if not seekable, implementation is free to destroy (compact) past read data
append::Bool # add data at end instead of at pointer
size::Int # end pointer (and write pointer if append == true) + offset
maxsize::Int # fixed array size (typically pre-allocated)
ptr::Int # read (and maybe write) pointer + offset
offset::Int # offset of ptr and size from actual start of data and actual size
mark::Int # reset mark location for ptr (or <0 for no mark)
function GenericIOBuffer{T}(data::T, readable::Bool, writable::Bool, seekable::Bool, append::Bool,
maxsize::Integer) where T<:AbstractVector{UInt8}
require_one_based_indexing(data)
return new(data, false, readable, writable, seekable, append, length(data), maxsize, 1, 0, -1)
end
end
const IOBuffer = GenericIOBuffer{Memory{UInt8}}
function GenericIOBuffer(data::T, readable::Bool, writable::Bool, seekable::Bool, append::Bool,
maxsize::Integer) where T<:AbstractVector{UInt8}
GenericIOBuffer{T}(data, readable, writable, seekable, append, maxsize)
end
function GenericIOBuffer(data::Vector{UInt8}, readable::Bool, writable::Bool, seekable::Bool, append::Bool,
maxsize::Integer)
ref = data.ref
buf = GenericIOBuffer(ref.mem, readable, writable, seekable, append, maxsize)
offset = memoryrefoffset(ref) - 1
buf.ptr += offset
buf.size = length(data) + offset
buf.offset = offset
return buf
end
# allocate Vector{UInt8}s for IOBuffer storage that can efficiently become Strings
StringMemory(n::Integer) = unsafe_wrap(Memory{UInt8}, _string_n(n))
StringVector(n::Integer) = wrap(Array, StringMemory(n))
# IOBuffers behave like Files. They are typically readable and writable. They are seekable. (They can be appendable).
"""
IOBuffer([data::AbstractVector{UInt8}]; keywords...) -> IOBuffer
Create an in-memory I/O stream, which may optionally operate on a pre-existing array.
It may take optional keyword arguments:
- `read`, `write`, `append`: restricts operations to the buffer; see `open` for details.
- `truncate`: truncates the buffer size to zero length.
- `maxsize`: specifies a size beyond which the buffer may not be grown.
- `sizehint`: suggests a capacity of the buffer (`data` must implement `sizehint!(data, size)`).
When `data` is not given, the buffer will be both readable and writable by default.
!!! warning "Passing `data` as scratch space to `IOBuffer` with `write=true` may give unexpected behavior"
Once `write` is called on an `IOBuffer`, it is best to consider any
previous references to `data` invalidated; in effect `IOBuffer` "owns"
this data until a call to `take!`. Any indirect mutations to `data`
could lead to undefined behavior by breaking the abstractions expected
by `IOBuffer`. If `write=true` the IOBuffer may store data at any
offset leaving behind arbitrary values at other offsets. If `maxsize > length(data)`,
the IOBuffer might re-allocate the data entirely, which
may or may not be visible in any outstanding bindings to `array`.
# Examples
```jldoctest
julia> io = IOBuffer();
julia> write(io, "JuliaLang is a GitHub organization.", " It has many members.")
56
julia> String(take!(io))
"JuliaLang is a GitHub organization. It has many members."
julia> io = IOBuffer(b"JuliaLang is a GitHub organization.")
IOBuffer(data=UInt8[...], readable=true, writable=false, seekable=true, append=false, size=35, maxsize=Inf, ptr=1, mark=-1)
julia> read(io, String)
"JuliaLang is a GitHub organization."
julia> write(io, "This isn't writable.")
ERROR: ArgumentError: ensureroom failed, IOBuffer is not writeable
julia> io = IOBuffer(UInt8[], read=true, write=true, maxsize=34)
IOBuffer(data=UInt8[...], readable=true, writable=true, seekable=true, append=false, size=0, maxsize=34, ptr=1, mark=-1)
julia> write(io, "JuliaLang is a GitHub organization.")
34
julia> String(take!(io))
"JuliaLang is a GitHub organization"
julia> length(read(IOBuffer(b"data", read=true, truncate=false)))
4
julia> length(read(IOBuffer(b"data", read=true, truncate=true)))
0
```
"""
function IOBuffer(
data::AbstractVector{UInt8};
read::Union{Bool,Nothing}=nothing,
write::Union{Bool,Nothing}=nothing,
append::Union{Bool,Nothing}=nothing,
truncate::Union{Bool,Nothing}=nothing,
maxsize::Integer=typemax(Int),
sizehint::Union{Integer,Nothing}=nothing)
if maxsize < 0
throw(ArgumentError("negative maxsize"))
end
if sizehint !== nothing
sizehint!(data, sizehint)
end
flags = open_flags(read=read, write=write, append=append, truncate=truncate)
buf = GenericIOBuffer(data, flags.read, flags.write, true, flags.append, Int(maxsize))
if flags.truncate
buf.size = buf.offset
end
return buf
end
function IOBuffer(;
read::Union{Bool,Nothing}=true,
write::Union{Bool,Nothing}=true,
append::Union{Bool,Nothing}=nothing,
truncate::Union{Bool,Nothing}=true,
maxsize::Integer=typemax(Int),
sizehint::Union{Integer,Nothing}=nothing)
size = sizehint !== nothing ? Int(sizehint) : maxsize != typemax(Int) ? Int(maxsize) : 32
flags = open_flags(read=read, write=write, append=append, truncate=truncate)
buf = IOBuffer(
StringMemory(size),
read=flags.read,
write=flags.write,
append=flags.append,
truncate=flags.truncate,
maxsize=maxsize)
fill!(buf.data, 0)
return buf
end
# PipeBuffers behave somewhat more like Unix Pipes (than Files). They are typically readable and writable, they act appendable, and are not seekable.
# However, they do not support stream notification, so for that there is the BufferStream wrapper around this.
"""
PipeBuffer(data::AbstractVector{UInt8}=UInt8[]; maxsize::Integer = typemax(Int))
An [`IOBuffer`](@ref) that allows reading and performs writes by appending.
Seeking and truncating are not supported.
See [`IOBuffer`](@ref) for the available constructors.
If `data` is given, creates a `PipeBuffer` to operate on a data vector,
optionally specifying a size beyond which the underlying `Array` may not be grown.
"""
PipeBuffer(data::AbstractVector{UInt8}=Memory{UInt8}(); maxsize::Int = typemax(Int)) =
GenericIOBuffer(data, true, true, false, true, maxsize)
PipeBuffer(maxsize::Integer) = (x = PipeBuffer(StringMemory(maxsize), maxsize = maxsize); x.size = 0; x)
_similar_data(b::GenericIOBuffer, len::Int) = similar(b.data, len)
_similar_data(b::IOBuffer, len::Int) = StringMemory(len)
function copy(b::GenericIOBuffer)
ret = typeof(b)(b.reinit ? _similar_data(b, 0) : b.writable ?
copyto!(_similar_data(b, length(b.data)), b.data) : b.data,
b.readable, b.writable, b.seekable, b.append, b.maxsize)
ret.size = b.size
ret.ptr = b.ptr
ret.mark = b.mark
ret.offset = b.offset
return ret
end
show(io::IO, b::GenericIOBuffer) = print(io, "IOBuffer(data=UInt8[...], ",
"readable=", b.readable, ", ",
"writable=", b.writable, ", ",
"seekable=", b.seekable, ", ",
"append=", b.append, ", ",
"size=", b.size - b.offset, ", ",
"maxsize=", b.maxsize == typemax(Int) ? "Inf" : b.maxsize, ", ",
"ptr=", b.ptr - b.offset, ", ",
"mark=", b.mark, ")")
@noinline function _throw_not_readable()
# See https://github.com/JuliaLang/julia/issues/29688.
throw(ArgumentError("read failed, IOBuffer is not readable"))
end
function unsafe_read(from::GenericIOBuffer, p::Ptr{UInt8}, nb::UInt)
from.readable || _throw_not_readable()
avail = bytesavailable(from)
adv = min(avail, nb)
unsafe_read!(p, from.data, from.ptr, adv)
from.ptr += adv
if nb > avail
throw(EOFError())
end
nothing
end
function unsafe_read!(dest::Ptr{UInt8}, src::AbstractVector{UInt8}, so::Integer, nbytes::UInt)
for i in 1:nbytes
unsafe_store!(dest, @inbounds(src[so+i-1]), i)
end
end
# Note: Currently, CodeUnits <: DenseVector, which makes this union redundant w.r.t
# DenseArrayType{UInt8}, but this is a bug, and may be removed in future versions
# of Julia. See #54002
const DenseBytes = Union{
<:DenseArrayType{UInt8},
CodeUnits{UInt8, <:Union{String, SubString{String}}},
}
function unsafe_read!(dest::Ptr{UInt8}, src::DenseBytes, so::Integer, nbytes::UInt)
GC.@preserve src unsafe_copyto!(dest, pointer(src, so), nbytes)
nothing
end
function peek(from::GenericIOBuffer, T::Union{Type{Int16},Type{UInt16},Type{Int32},Type{UInt32},Type{Int64},Type{UInt64},Type{Int128},Type{UInt128},Type{Float16},Type{Float32},Type{Float64}})
from.readable || _throw_not_readable()
avail = bytesavailable(from)
nb = sizeof(T)
if nb > avail
throw(EOFError())
end
GC.@preserve from begin
ptr::Ptr{T} = pointer(from.data, from.ptr)
x = unsafe_load(ptr)
end
return x
end
function read(from::GenericIOBuffer, T::Union{Type{Int16},Type{UInt16},Type{Int32},Type{UInt32},Type{Int64},Type{UInt64},Type{Int128},Type{UInt128},Type{Float16},Type{Float32},Type{Float64}})
x = peek(from, T)
from.ptr += sizeof(T)
return x
end
function read_sub(from::GenericIOBuffer, a::AbstractArray{T}, offs, nel) where T
require_one_based_indexing(a)
from.readable || _throw_not_readable()
if offs+nel-1 > length(a) || offs < 1 || nel < 0
throw(BoundsError())
end
if isa(a, MutableDenseArrayType{UInt8})
nb = UInt(nel * sizeof(T))
GC.@preserve a unsafe_read(from, pointer(a, offs), nb)
else
for i = offs:offs+nel-1
a[i] = read(from, T)
end
end
return a
end
@inline function read(from::GenericIOBuffer, ::Type{UInt8})
from.readable || _throw_not_readable()
ptr = from.ptr
size = from.size
if ptr > size
throw(EOFError())
end
@inbounds byte = from.data[ptr]::UInt8
from.ptr = ptr + 1
return byte
end
function peek(from::GenericIOBuffer, ::Type{UInt8})
from.readable || _throw_not_readable()
if from.ptr > from.size
throw(EOFError())
end
return from.data[from.ptr]::UInt8
end
read(from::GenericIOBuffer, ::Type{Ptr{T}}) where {T} = convert(Ptr{T}, read(from, UInt))
isreadable(io::GenericIOBuffer) = io.readable
iswritable(io::GenericIOBuffer) = io.writable
filesize(io::GenericIOBuffer) = (io.seekable ? io.size - io.offset : bytesavailable(io))
bytesavailable(io::GenericIOBuffer) = io.size - io.ptr + 1
position(io::GenericIOBuffer) = io.ptr - io.offset - 1
function skip(io::GenericIOBuffer, n::Integer)
skip(io, clamp(n, Int))
end
function skip(io::GenericIOBuffer, n::Int)
if signbit(n)
seekto = clamp(widen(position(io)) + widen(n), Int)
seek(io, seekto) # Does error checking
else
n_max = io.size + 1 - io.ptr
io.ptr += min(n, n_max)
io
end
end
function seek(io::GenericIOBuffer, n::Integer)
seek(io, clamp(n, Int))
end
function seek(io::GenericIOBuffer, n::Int)
if !io.seekable
ismarked(io) || throw(ArgumentError("seek failed, IOBuffer is not seekable and is not marked"))
n == io.mark || throw(ArgumentError("seek failed, IOBuffer is not seekable and n != mark"))
end
# TODO: REPL.jl relies on the fact that this does not throw (by seeking past the beginning or end
# of an GenericIOBuffer), so that would need to be fixed in order to throw an error here
#(n < 0 || n > io.size - io.offset) && throw(ArgumentError("Attempted to seek outside IOBuffer boundaries."))
#io.ptr = n + io.offset + 1
io.ptr = clamp(n, 0, io.size - io.offset) + io.offset + 1
return io
end
function seekend(io::GenericIOBuffer)
io.ptr = io.size+1
return io
end
# choose a resize strategy based on whether `resize!` is defined:
# for a Vector, we use `resize!`, but for most other types,
# this calls `similar`+copy
function _resize!(io::GenericIOBuffer, sz::Int)
a = io.data
offset = io.offset
if applicable(resize!, a, sz)
if offset != 0
size = io.size
size > offset && copyto!(a, 1, a, offset + 1, min(sz, size - offset))
io.ptr -= offset
io.size -= offset
io.offset = 0
end
resize!(a, sz)
else
size = io.size
if size >= sz && sz != 0
b = a
else
b = _similar_data(io, sz == 0 ? 0 : max(overallocation(size - io.offset), sz))
end
size > offset && copyto!(b, 1, a, offset + 1, min(sz, size - offset))
io.data = b
io.ptr -= offset
io.size -= offset
io.offset = 0
end
return io
end
function truncate(io::GenericIOBuffer, n::Integer)
io.writable || throw(ArgumentError("truncate failed, IOBuffer is not writeable"))
io.seekable || throw(ArgumentError("truncate failed, IOBuffer is not seekable"))
n < 0 && throw(ArgumentError("truncate failed, n bytes must be ≥ 0, got $n"))
n > io.maxsize && throw(ArgumentError("truncate failed, $(n) bytes is exceeds IOBuffer maxsize $(io.maxsize)"))
n = Int(n)
if io.reinit
io.data = _similar_data(io, n)
io.reinit = false
elseif n > length(io.data) + io.offset
_resize!(io, n)
end
ismarked(io) && io.mark > n && unmark(io)
n += io.offset
io.data[io.size+1:n] .= 0
io.size = n
io.ptr = min(io.ptr, n+1)
return io
end
function compact(io::GenericIOBuffer)
io.writable || throw(ArgumentError("compact failed, IOBuffer is not writeable"))
io.seekable && throw(ArgumentError("compact failed, IOBuffer is seekable"))
io.reinit && return
local ptr::Int, bytes_to_move::Int
if ismarked(io) && io.mark < position(io)
io.mark == 0 && return
ptr = io.mark + io.offset
bytes_to_move = bytesavailable(io) + (io.ptr - ptr)
else
ptr = io.ptr
bytes_to_move = bytesavailable(io)
end
copyto!(io.data, 1, io.data, ptr, bytes_to_move)
io.size -= ptr - 1
io.ptr -= ptr - 1
io.offset = 0
return
end
@noinline function ensureroom_slowpath(io::GenericIOBuffer, nshort::UInt)
io.writable || throw(ArgumentError("ensureroom failed, IOBuffer is not writeable"))
if io.reinit
io.data = _similar_data(io, nshort % Int)
io.reinit = false
end
if !io.seekable
if !ismarked(io) && io.ptr > io.offset+1 && io.size <= io.ptr - 1
io.ptr = 1
io.size = 0
io.offset = 0
else
datastart = (ismarked(io) ? io.mark : io.ptr - io.offset)
if (io.size-io.offset+nshort > io.maxsize) ||
(datastart > 4096 && datastart > io.size - io.ptr) ||
(datastart > 262144)
# apply somewhat arbitrary heuristics to decide when to destroy
# old, read data to make more room for new data
compact(io)
end
end
end
return
end
@inline ensureroom(io::GenericIOBuffer, nshort::Int) = ensureroom(io, UInt(nshort))
@inline function ensureroom(io::GenericIOBuffer, nshort::UInt)
if !io.writable || (!io.seekable && io.ptr > io.offset+1) || io.reinit
ensureroom_slowpath(io, nshort)
end
n = min((nshort % Int) + (io.append ? io.size : io.ptr-1) - io.offset, io.maxsize)
l = length(io.data) + io.offset
if n > l
_resize!(io, Int(n))
end
return io
end
eof(io::GenericIOBuffer) = (io.ptr - 1 >= io.size)
function closewrite(io::GenericIOBuffer)
io.writable = false
nothing
end
@noinline function close(io::GenericIOBuffer{T}) where T
io.readable = false
io.writable = false
io.seekable = false
io.size = 0
io.offset = 0
io.maxsize = 0
io.ptr = 1
io.mark = -1
if io.writable && !io.reinit
io.data = _resize!(io, 0)
end
nothing
end
isopen(io::GenericIOBuffer) = io.readable || io.writable || io.seekable || bytesavailable(io) > 0
"""
take!(b::IOBuffer)
Obtain the contents of an `IOBuffer` as an array. Afterwards, the `IOBuffer` is reset to its initial state.
# Examples
```jldoctest
julia> io = IOBuffer();
julia> write(io, "JuliaLang is a GitHub organization.", " It has many members.")
56
julia> String(take!(io))
"JuliaLang is a GitHub organization. It has many members."
```
"""
function take!(io::GenericIOBuffer)
ismarked(io) && unmark(io)
if io.seekable
nbytes = io.size - io.offset
data = copyto!(StringVector(nbytes), 1, io.data, io.offset + 1, nbytes)
else
nbytes = bytesavailable(io)
data = read!(io, StringVector(nbytes))
end
if io.writable
io.ptr = 1
io.size = 0
io.offset = 0
end
return data
end
function take!(io::IOBuffer)
ismarked(io) && unmark(io)
if io.seekable
nbytes = filesize(io)
if nbytes == 0 || io.reinit
data = StringVector(0)
elseif io.writable
data = wrap(Array, memoryref(io.data, io.offset + 1), nbytes)
else
data = copyto!(StringVector(nbytes), 1, io.data, io.offset + 1, nbytes)
end
else
nbytes = bytesavailable(io)
if nbytes == 0
data = StringVector(0)
elseif io.writable
data = wrap(Array, memoryref(io.data, io.ptr), nbytes)
else
data = read!(io, data)
end
end
if io.writable
io.reinit = true
io.ptr = 1
io.size = 0
io.offset = 0
end
return data
end
"""
_unsafe_take!(io::IOBuffer)
This simply returns the raw resized `io.data`, with no checks to be
sure that `io` is readable etcetera, and leaves `io` in an inconsistent
state. This should only be used internally for performance-critical
`String` routines that immediately discard `io` afterwards, and it
*assumes* that `io` is writable and seekable.
It might save an allocation compared to `take!` (if the compiler elides the
Array allocation), as well as omits some checks.
"""
_unsafe_take!(io::IOBuffer) =
wrap(Array, io.size == io.offset ?
memoryref(Memory{UInt8}()) :
memoryref(io.data, io.offset + 1),
io.size - io.offset)
function write(to::IO, from::GenericIOBuffer)
written::Int = bytesavailable(from)
if to === from
from.ptr = from.size + 1
else
written = GC.@preserve from unsafe_write(to, pointer(from.data, from.ptr), UInt(written))
from.ptr += written
end
return written
end
function unsafe_write(to::GenericIOBuffer, p::Ptr{UInt8}, nb::UInt)
ensureroom(to, nb)
ptr = (to.append ? to.size+1 : to.ptr)
written = Int(min(nb, Int(length(to.data))::Int - ptr + 1))
towrite = written
d = to.data
while towrite > 0
@inbounds d[ptr] = unsafe_load(p)
ptr += 1
p += 1
towrite -= 1
end
to.size = max(to.size, ptr - 1)
if !to.append
to.ptr += written
end
return written
end
@inline function write(to::GenericIOBuffer, a::UInt8)
ensureroom(to, UInt(1))
ptr = (to.append ? to.size+1 : to.ptr)
if ptr > to.maxsize
return 0
else
to.data[ptr] = a
end
to.size = max(to.size, ptr)
if !to.append
to.ptr += 1
end
return sizeof(UInt8)
end
readbytes!(io::GenericIOBuffer, b::MutableDenseArrayType{UInt8}, nb=length(b)) = readbytes!(io, b, Int(nb))
function readbytes!(io::GenericIOBuffer, b::MutableDenseArrayType{UInt8}, nb::Int)
nr = min(nb, bytesavailable(io))
if length(b) < nr
resize!(b, nr)
end
read_sub(io, b, 1, nr)
return nr
end
read(io::GenericIOBuffer) = read!(io, StringVector(bytesavailable(io)))
readavailable(io::GenericIOBuffer) = read(io)
read(io::GenericIOBuffer, nb::Integer) = read!(io, StringVector(min(nb, bytesavailable(io))))
function occursin(delim::UInt8, buf::IOBuffer)
p = pointer(buf.data, buf.ptr)
q = GC.@preserve buf ccall(:memchr, Ptr{UInt8}, (Ptr{UInt8}, Int32, Csize_t), p, delim, bytesavailable(buf))
return q != C_NULL
end
function occursin(delim::UInt8, buf::GenericIOBuffer)
data = buf.data
for i = buf.ptr:buf.size
@inbounds b = data[i]
b == delim && return true
end
return false
end
function copyuntil(out::IO, io::GenericIOBuffer, delim::UInt8; keep::Bool=false)
data = view(io.data, io.ptr:io.size)
# note: findfirst + copyto! is much faster than a single loop
# except for nout ≲ 20. A single loop is 2x faster for nout=5.
nout = nread = something(findfirst(==(delim), data), length(data))
if !keep && nout > 0 && data[nout] == delim
nout -= 1
end
write(out, view(io.data, io.ptr:io.ptr+nout-1))
io.ptr += nread
return out
end
function copyline(out::GenericIOBuffer, s::IO; keep::Bool=false)
copyuntil(out, s, 0x0a, keep=true)
line = out.data
i = out.size # XXX: this is only correct for appended data. if the data was inserted, only ptr should change
if keep || i == out.offset || line[i] != 0x0a
return out
elseif i < 2 || line[i-1] != 0x0d
i -= 1
else
i -= 2
end
out.size = i
if !out.append
out.ptr = i+1
end
return out
end
function _copyline(out::IO, io::GenericIOBuffer; keep::Bool=false)
data = view(io.data, io.ptr:io.size)
# note: findfirst + copyto! is much faster than a single loop
# except for nout ≲ 20. A single loop is 2x faster for nout=5.
nout = nread = something(findfirst(==(0x0a), data), length(data))
if !keep && nout > 0 && data[nout] == 0x0a
nout -= 1
nout > 0 && data[nout] == 0x0d && (nout -= 1)
end
write(out, view(io.data, io.ptr:io.ptr+nout-1))
io.ptr += nread
return out
end
copyline(out::IO, io::GenericIOBuffer; keep::Bool=false) = _copyline(out, io; keep)
copyline(out::GenericIOBuffer, io::GenericIOBuffer; keep::Bool=false) = _copyline(out, io; keep)
# copy-free crc32c of IOBuffer:
function _crc32c(io::IOBuffer, nb::Integer, crc::UInt32=0x00000000)
nb < 0 && throw(ArgumentError("number of bytes to checksum must be ≥ 0, got $nb"))
io.readable || _throw_not_readable()
n = min(nb, bytesavailable(io))
n == 0 && return crc
crc = GC.@preserve io unsafe_crc32c(pointer(io.data, io.ptr), n, crc)
io.ptr += n
return crc
end
_crc32c(io::IOBuffer, crc::UInt32=0x00000000) = _crc32c(io, bytesavailable(io), crc)