When (*bufio.Writer).ReadFrom is called with a partially filled buffer,
fill out and flush the buffer and then call the underlying writer's
ReadFrom method if present.
Fixes#44815.
Change-Id: I15b3ef0746d0d60fd62041189a9b9df11254dd29
Reviewed-on: https://go-review.googlesource.com/c/go/+/340530
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Discard is not really a read operation, and in theory it could
Seek the underlying Reader without actually reading anything,
so an UnreadByte following a Discard is disallowed.
Similarly, although WriteTo usually does end up calling Read on the
underlying buffer, if the underlying Reader implements io.WriterTo it
may instead terminate in a call to WriteTo, without ever buffering or
even seeing the last byte written. (It is conceptually read-like, but
not strictly “a read operation”.)
Fixes#48446
Change-Id: Ide6f2b157332b423486810399f66140c914144e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/351810
Trust: Bryan C. Mills <bcmills@google.com>
Trust: Joe Tsai <joetsai@digital-static.net>
Reviewed-by: Joe Tsai <joetsai@digital-static.net>
This adds a new Writer.AvailableBuffer method that returns
an empty buffer with a possibly non-empty capacity for use
with append-like APIs.
The typical usage pattern is something like:
b := bw.AvailableBuffer()
b = appendValue(b, v)
bw.Write(b)
It allows logic combining append-like APIs with bufio.Writer to avoid
needing to allocate and manage buffers themselves and allows the
append-like APIs to directly write into the buffer for a bufio.Writer.
Fixes#47527
Change-Id: I9cd169f3f8e8c7cd40818caf3daf1944c826fc66
Reviewed-on: https://go-review.googlesource.com/c/go/+/345569
Trust: Joe Tsai <joetsai@digital-static.net>
Run-TryBot: Joe Tsai <joetsai@digital-static.net>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For batch allocation reasons, it would be useful to nest a
bufio.Reader or bufio.Writer in a struct as a value,
rather than a pointer. When the Reset method is called,
have it use the default buffer size if the buffer is nil.
Fixes#45374
Change-Id: I80df18a13575431428a42ed150a1579de1282637
Reviewed-on: https://go-review.googlesource.com/c/go/+/345570
Trust: Joe Tsai <joetsai@digital-static.net>
Run-TryBot: Joe Tsai <joetsai@digital-static.net>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The old ioutil references are still valid, but update our code
to reflect best practices and get used to the new locations.
Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.
Also excluded vendored code.
For #41190.
Change-Id: I6d86f2bf7bc37a9d904b6cee3fe0c7af6d94d5b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/263142
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Instead use string(r) where r has type rune.
This is in preparation for a vet warning for string(i).
Updates #32479
Change-Id: Ic205269bba1bd41723950219ecfb67ce17a7aa79
Reviewed-on: https://go-review.googlesource.com/c/go/+/220844
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Akhil Indurti <aindurti@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Toshihiro Shiino <shiino.toshihiro@gmail.com>
If a previous Write returned an error, any subsequent Write or ReadFrom
must return that error before any operations.
However, only Write behaved correctly and this change fixes that problem
by making sure that ReadFrom firstly checks for the underlying error.
Fixes#35194
Change-Id: I31356a9e8bd945bc0168b2e3be470f3ae69d4813
Reviewed-on: https://go-review.googlesource.com/c/go/+/204000
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
If reading 0 bytes, don't return the error from the underlying
io.Reader if there is still data buffered.
Fixes#32693
Change-Id: I12a97bd6003c638c15d41028942f27edf88340e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/182997
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Since Reader.Peek potentially reads from the underlying io.Reader,
discarding previous buffers, UnreadRune and UnreadByte cannot
necessarily work. Change Peek to invalidate the unread buffers in all
cases (as allowed according to the documentation) and thus prevent
hiding bugs in the caller.
(This change was previoiusly merged and then reverted due concern about
being too close to a release)
Fixes#18556
Change-Id: I9027d75aa834d4b27703f37711ba25de04d89f3c
GitHub-Last-Rev: 917ef1e511
GitHub-Pull-Request: golang/go#28768
Reviewed-on: https://go-review.googlesource.com/c/149297
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Go 1.9 beta 2 is already out.
It's too late to break code with a change like this.
This can be rolled forward for Go 1.10.
This reverts commit ae238688d2.
Change-Id: Ib67b8629e3deac5d50d76581aba6a91ca7a7853e
Reviewed-on: https://go-review.googlesource.com/47570
Reviewed-by: Russ Cox <rsc@golang.org>
Since Reader.Peek potentially reads from the underlying io.Reader,
discarding previous buffers, UnreadRune and UnreadByte cannot
necessarily work. Change Peek to invalidate the unread buffers in all
cases (as allowed according to the documentation) and thus prevent
hiding bugs in the caller.
Fixes#18556
Change-Id: I8d836db7ce31c4aaecb4f61c24573b0332bbf30d
Reviewed-on: https://go-review.googlesource.com/46850
Reviewed-by: Robert Griesemer <gri@golang.org>
CL/19862 (f79b50b8d5) recently introduced the constants
SeekStart, SeekCurrent, and SeekEnd to the io package. We should use these constants
consistently throughout the code base.
Updates #15269
Change-Id: If7fcaca7676e4a51f588528f5ced28220d9639a2
Reviewed-on: https://go-review.googlesource.com/22097
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Joe Tsai <joetsai@digital-static.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The existing implementation returns nil, ErrBufferFull when n > len(b.buf),
now it will return any data in the buffer and ErrBufferFull.
Fixes#14121
Change-Id: Ie52d32ccd80e4078ebfae6e75393c89675959ead
Reviewed-on: https://go-review.googlesource.com/19091
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reader.Discard is the complement to Peek. It discards the next n bytes
of input.
We already have Reader.Buffered to see how many bytes of data are
sitting available in memory, and Reader.Peek to get that that buffer
directly. But once you're done with the Peek'd data, you can't get rid
of it, other than Reading it.
Both Read and io.CopyN(ioutil.Discard, bufReader, N) are relatively
slow. People instead resort to multiple blind ReadByte calls, just to
advance the internal b.r variable.
I've wanted this previously, several people have asked for it in the
past on golang-nuts/dev, and somebody just asked me for it again in a
private email. There are a few places in the standard library we'd use
it too.
Change-Id: I85dfad47704a58bd42f6867adbc9e4e1792bc3b0
Reviewed-on: https://go-review.googlesource.com/2260
Reviewed-by: Russ Cox <rsc@golang.org>
