Alex Dowad [Tue, 12 May 2020 06:43:29 +0000 (08:43 +0200)]
Further refactoring of proc_open.c
This time a number of comments have been added to make it easy for new devs to understand
what is going on. Also adjusted error message to use colons rather than dashes.
Previously, if a resource which was *not* of type "stream" was passed, proc_open would
return without freeing dynamically allocated memory. It's fixed now.
Alex Dowad [Sun, 3 May 2020 15:54:06 +0000 (17:54 +0200)]
Add PTY support to proc_open (again after 16 long years)
Back in 2004, a feature was added to proc_open which allowed it to open a PTY,
connecting specific FDs in the child process to the slave end of the PTY and returning
the master end of the PTY (wrapped as a PHP stream) in the `$pipes` array. However,
this feature was disabled just about a month later. Little information is available
about why this was done, but from talking to the original implementer, it seems there
were portability problems with some rare flavors of Unix.
Re-enable this feature with a simplified implementation which uses openpty(). No
attempt is made to support PTYs if the platform does not have openpty(). The configure
script checks if linking with -lutil is necessary to use openpty(), but if anything
else is required, like including some special header or linking with some other library,
PTY support will be disabled.
The original PTY support for proc_open automatically daemonized the child process
(disassociating it from the TTY session and process group of the parent). However,
I don't think this is a good idea. Just because a user opens a child process in a
PTY, it doesn't mean they want it to continue running even when the parent process
is killed. Of course, if the child process is some kind of server, it will likely
daemonize itself; but we have no reason to preempt that decision.
It turns out that since 2015, there has been one test case for PTY support in
proc_open() in the test suite. This test was added in GitHub PR #1588
(https://github.com/php/php-src/pull/1588). That PR mentioned that the PHP
binary in the Debian/Ubuntu repositories is patched to *enable* PTY support. Checking
the Debian PHP repository (https://salsa.debian.org/php-team/php.git) shows that this
is still true. Debian's patch does not modify the implementation from 2004 in any
way; it just removes the #if 0 line which disables it.
Naturally, the test case is skipped if PTY support is not enabled. This means that ever
since it was added, every test run against the 'vanilla' PHP codebase has skipped it.
Interestingly, the test case which was added in 2015 fails on my Linux Mint PC... both
with this simplified implementation *and* when enabling the original implementation.
Investigation reveals the reason: when the child process using the slave end of the
PTY exits and its FDs are all closed, and all buffered data is read from the master
end of the PTY, any further attempt to read from the master end fails with EIO. The
test case seems to expect that reading from the master end will always return an
empty string if no data is available.
Likely this is because PHP's fread() was updated to report errors from the underlying
system calls only recently.
One way out of this dilemma: IF at least one FD referring to the slave end of the PTY is
kept open *in the parent process*, the failure with EIO will not occur even after the child
process exits. However, that would raise another issue: we would need a way to ensure the FD
will be closed eventually in long-running programs.
Another discovery made while testing this code is that fread() does not always return
all the data written to the slave end of the PTY in a single call, even if the data was
written with a single syscall and it is only a few bytes long.
Specifically, when the child process in the test case writes "foo\n" to the PTY, the parent
sometimes receives "foo" (3 bytes) and sometimes "foo\r\n" (5 bytes). (The "\r" is from the
TTY line discipline converting "\n" to "\r\n".) A second call to fread() does return the
remaining bytes, though sometimes all the data is read in the first call, and by the time
the second call is made, the child process has already exited. It seems that liberal use
of the @ operator is needed when using fread() on pipes.
Thanks to Nikita Popov for suggesting that we should just use openpty() rather than
grantpt(), unlockpt(), etc.
Gerard Roche [Wed, 13 May 2020 18:57:54 +0000 (19:57 +0100)]
Fix lcov genhtml: ERROR: cannot read [file]
lcov is emitting several errors for generated regex files that have no code
coverage data. The fix is to add the files to the lcov exlusion list.
This is not an issue for CI because it uses gcovr to generate code coverage.
The errors:
Processing ext/date/lib/parse_date.gcda
geninfo: WARNING: could not open /home/code/vendor/php/php-src/parse_date.re
geninfo: WARNING: could not open /home/code/vendor/php/php-src/<stdout>
geninfo: WARNING: some exclusion markers may be ignored
Processing ext/date/lib/parse_tz.gcda
Processing ext/date/lib/tm2unixtime.gcda
Processing ext/date/lib/parse_iso_intervals.gcda
geninfo: WARNING: could not open /home/code/vendor/php/php-src/<stdout>
geninfo: WARNING: could not open /home/code/vendor/php/php-src/parse_iso_intervals.re
geninfo: WARNING: some exclusion markers may be ignored
...
genhtml: ERROR: cannot read /home/code/vendor/php/php-src/parse_date.re
Processing file /home/code/vendor/php/php-src/parse_date.re
make: *** [Makefile:443: lcov-html] Error 2
To solve bug #70886, the test uses random keys to prevent collisions;
however, this is not guaranteed, and as such it may even collide with
other tests in the shmop test suite. The proper solution would be to
use a single key (which could be randomly generated), but to actually
`shmop_close()` after each `shmop_delete()`. This would, however, not
work on Windows due to bug #65987. Therefore we use three different
keys for now.
Nikita Popov [Wed, 13 May 2020 12:46:15 +0000 (14:46 +0200)]
Rename zend_zval_get_type() API
We have a bunch of APIs for getting type names and it's sometimes
hard to keep them apart ... make it clear that this is the one
you definitely do not want to use.
Alex Dowad [Wed, 6 May 2020 20:02:57 +0000 (22:02 +0200)]
Honor script time limit when calling shutdown functions
A time limit can be set on PHP script execution via `set_time_limit` (or .ini file).
When the time limit is reached, the OS will notify PHP and `timed_out` and `vm_interrupt`
flags are set. While these flags are regularly checked when executing PHP code, once the
end of the script is reached, they are not checked while invoking shutdown functions
(registered via `register_shutdown_function`).
Of course, if the shutdown functions are implemented *in* PHP, then the interrupt flag
will be checked while the VM is running PHP bytecode and the timeout will take effect.
But if the shutdown functions are built-in (implemented in C), it will not.
Since the shutdown functions are invoked through `zend_call_function`, add a check of the
`vm_interrupt` flag there. Then, the script time limit will be respected when *entering*
each shutdown function. The fact still remains that if a shutdown function is built-in and
runs for a long time, script execution will not time out until it finishes and the
interpreter tries to invoke the next one.
Still, the behavior of scripts with execution time limits will be more consistent after
this patch. To make the execution time-out feature work even more precisely, it would
be necessary to scrutinize all the built-in functions and add checks of the `vm_interrupt`
flag in any which can run for a long time. That might not be worth the effort, though.
It should be mentioned that this patch does not solely affect shutdown functions, neither
does it solely allow for interruption of running code due to script execution timeout.
Anything else which causes `vm_interrupt` to be set, such as the PHP interpreter receiving
a signal, will take effect when exiting from an internal function. And not just internal
functions which are called because they were registered to run at shutdown; there are
other cases where a series of internal functions might run in the midst of a script. In
all such cases, it will be possible to interrupt the interpreter now.
Gerard Roche [Tue, 12 May 2020 16:24:21 +0000 (17:24 +0100)]
run-tests: cs fixes (cleanup)
I used php-cs-fixer to do the cs fixes. The configuration I used is
posted below. The reason I disabled some of the rules is because they
create too much noise and would make it difficult to review. But please
feel free to close this PR and run the php-cs-fixer yourself.
Alex Dowad [Thu, 23 Apr 2020 08:45:20 +0000 (10:45 +0200)]
SplDoublyLinkedList uses iteration flags in iterator struct
The 'flags' field in spl_dllist_it was formerly unused. This means that if one started to
iterate over an SplDoublyLinkedList using 'foreach', and then *changed* the iteration mode
halfway, the 'foreach' loop would start iterating in the opposite direction. Probably this
was not what was intended.
Therefore, use the 'flags' field in spl_dllist_it for iteration via 'foreach'. For explicit
iteration using methods like '::next()' and '::current()', continue to use the flags in
the SplDoublyLinkedList object itself.
Alex Dowad [Wed, 6 May 2020 20:22:07 +0000 (22:22 +0200)]
zend_timeout is not a signal handler function
The 'int dummy' parameter to this function makes it appear that it was intended as a
signal handler, but it is not being used as such. So remove the redundant parameter.
Gerard Roche [Tue, 12 May 2020 09:07:18 +0000 (10:07 +0100)]
run-tests: remove use of FILE_BINARY constant
The FILE_BINARY (and FILE_TEXT) constants are not really valid or useful
constants. It looks like they were added in 5.2.7 and have "no effect,
and are only available for forward compatibility."
* PHP-7.4:
Fix #78876: Long variables cause OOM and temp files are not cleaned
Fix #78875: Long filenames cause OOM and temp files are not cleaned
Update NEWS for 7.2.31
Update CREDITS for PHP 7.2.30
Update NEWS for PHP 7.2.30
* PHP-7.3:
Fix #78876: Long variables cause OOM and temp files are not cleaned
Fix #78875: Long filenames cause OOM and temp files are not cleaned
Update NEWS for 7.2.31
Update CREDITS for PHP 7.2.30
Update NEWS for PHP 7.2.30
* PHP-7.2:
Fix #78876: Long variables cause OOM and temp files are not cleaned
Fix #78875: Long filenames cause OOM and temp files are not cleaned
Update NEWS for 7.2.31
Update CREDITS for PHP 7.2.30
Update NEWS for PHP 7.2.30
Fix #78875: Long filenames cause OOM and temp files are not cleaned
We must not cast `size_t` to `int` (unless the `size_t` value is
guaranteed to be less than or equal to `INT_MAX`). In this case we can
declare `array_len` as `size_t` in the first place.
These APIs have been superseded by ReflectionParameter::getType()
since PHP 7.0. Types introduced since that time are not available
through the old APIs, and their behavior is getting increasingly
confusing. This is how they interact with PHP 8 union types:
* isArray() will return true if the type is array or ?array,
but not any other union type
* Same for isCallable().
* getClass() will return a class for T|int etc, as long as the
union only contains a single type. T1|T2 will return null.
This behavior is not particularly reasonable or useful, and will
get more confusing as new type system extensions are added.
We must not attempt to access arbitrary union members when retrieving
debug info, because that may not be valid. Therefore we do no longer
dereference pointer types inside of unions, but report their address as
string in `%p` format instead.
array_column() reimplements array key handling in a way that does
not match standard array key behavior in PHP. Avoid this by making
use of the standard API.
Of course, there is a minor backwards compatibilty break here,
e.g. people could be relying on objects getting cast to string
instead of throwing.
Nikita Popov [Thu, 31 Oct 2019 10:27:53 +0000 (11:27 +0100)]
Reapply "Remove configure checks for supported instruction sets"
I reverted this previously for 7.4 because of bug #78769. Relanding
it now for master, because I still believe that this change is
right, and if it causes complications, those indicate a bug elsewhere.
---
These were checking whether the instruction set is supported by
the host CPU, however they were only used to condition on whether
this instruction set is targeted at all. It would still use dynamic
dispatch (e.g. based on ifunc resolvers) to select the actual
implementation. Whether the target is guaranteed to support the
instruction set without dispatch is determined based on pre-defined
macros like __SSE2__.
This removes the configure-time builtin cpu checks to remove
confusion. Additionally this allows targeting an architecture that
is newer than the host architecture.
Commit aaa1f90[1] dropped support for the custom `I` specifier, so we
must no longer use it for `ZEND_ADDR_FMT`; otherwise there are
segfaults when printing memory leaks, and maybe elsewhere.
Alex Dowad [Sun, 10 May 2020 12:57:12 +0000 (14:57 +0200)]
Don't check directory atime in lstat_stat_variation10.phpt test
This is a funny one. I discovered that lstat_stat_variation10.phpt was failing every
now and again when the PHP test suite was run on my dev PC. The output from the failing
test showed that the atime (access time) of the directory created in the test was changing
between these lines:
Could is_dir() be accessing the directory and changing the atime? strace showed that is_dir
was only issuing a single stat() syscall. Could stat() change the atime? No, no, that would
just be perverse. Nobody would be stupid enough to implement the kernel in that way.
Checked the kernel source, found that the function called when atime needs to be updated
appears to be touch_atime(). Broke out the BCC kernel tracing tools and ran this one
while running the flaky test case in a loop:
Inspecting the results showed that something called "git_thread" was occcasionally updating
the atime on the directory in question!! What on earth...???
The PID shown by trace revealed that this was a background thread for Sublime Text 3.
Sublime now has git integration and shows when there are untracked or modified files. It
seems that it uses a background thread to regularly scan the project directory and look
for new and modified files. This was causing the atime to change.
Even though other developers may not be running ST3, there are any number of reasons why
a background process might recurse through various directories and could cause the atime
to change unexpectedly. Therefore, update the test case so it doesn't fail in such cases.
Nikita Popov [Sat, 9 May 2020 09:53:39 +0000 (11:53 +0200)]
Fix bug68996.phpt test
The function name gets printed here now, with illegal chars
substituted in the arg. This slipped through previously, because
the test only runs under USE_ZEND_ALLOC=0. We remove that check
as well, because the test behaves the same regardless of which
allocator is used, even if the original bug only reproduces under
USE_ZEND_ALLOC=0.
Máté Kocsis [Sat, 29 Feb 2020 21:47:04 +0000 (22:47 +0100)]
Make float to string casts locale-independent
From now on, float to string casting will always behave locale-independently.
RFC: https://wiki.php.net/rfc/locale_independent_float_to_string
Closes GH-5224
Co-authored-by: George Peter Banyard <girgias@php.net>