Fix#5272
The consumption of a readable stream is a dance with 3 partners.
1. The specific stream Author (A)
2. The Stream Base class (B), and
3. The Consumer of the stream (C)
When B calls the _read() method that A implements, it sets a 'reading'
flag, so that parallel calls to _read() can be avoided. When A calls
stream.push(), B knows that it's safe to start calling _read() again.
If the consumer C is some kind of parser that wants in some cases to
pass the source stream off to some other party, but not before "putting
back" some bit of previously consumed data (as in the case of Node's
websocket http upgrade implementation). So, stream.unshift() will
generally *never* be called by A, but *only* called by C.
Prior to this patch, stream.unshift() *also* unset the state.reading
flag, meaning that C could indicate the end of a read, and B would
dutifully fire off another _read() call to A. This is inappropriate.
In the case of fs streams, and other variably-laggy streams that don't
tolerate overlapped _read() calls, this causes big problems.
Also, calling stream.shift() after the 'end' event did not raise any
kind of error, but would cause very strange behavior indeed. Calling it
after the EOF chunk was seen, but before the 'end' event was fired would
also cause weird behavior, and could lead to data being lost, since it
would not emit another 'readable' event.
This change makes it so that:
1. stream.unshift() does *not* set state.reading = false
2. stream.unshift() is allowed up until the 'end' event.
3. unshifting onto a EOF-encountered and zero-length (but not yet
end-emitted) stream will defer the 'end' event until the new data is
consumed.
4. pushing onto a EOF-encountered stream is now an error.
So, if you read(), you have that single tick to safely unshift() data
back into the stream, even if the null chunk was pushed, and the length
was 0.
On Linux, positional writes don't work when the file is opened in
append mode. The kernel ignores the position argument and always
appends the data to the end of the file.
To quote the man page:
POSIX requires that opening a file with the O_APPEND flag should have
no affect on the location at which pwrite() writes data. However, on
Linux, if a file is opened with O_APPEND, pwrite() appends data to the
end of the file, regardless of the value of offset.
Expand the JSON representation of Buffer to include type information
so that it can be deserialized in JSON.parse() without context.
Fixes#5110.
Fixes#5143.
_charsWritten is an internal property that was constantly written to,
but never read from. So it has been removed.
Removed documentation reference as well.
Add the `sessionTimeout` integral value to the list of options
recognized by `tls.createServer`.
This option will be useful for applications which need frequently
establish short-lived TLS connections to the same endpoint. The TLS
tickets RFC is an ideal option to reduce the socket setup overhead
for such scenarios, but the default ticket timeout value (5
minutes) is too low to be useful.
Commit f53441a added crypto.getCiphers() as a function that returns the
names of SSL ciphers.
Commit 14a6c4e then added crypto.getHashes(), which returns the names of
digest algorithms, but that creates a subtle inconsistency: the return
values of crypto.getHashes() are valid arguments to crypto.createHash()
but that is not true for crypto.getCiphers() - the returned values are
only valid for SSL/TLS functions.
Rectify that by adding tls.getCiphers() and making crypto.getCiphers()
return proper cipher names.
Since WriteBuffer has been replaced with WriteOneByte, writing ascii
will no longer automatically convert 0x0 to 0x20. So removed mention of
this special case from docs.