We were checking for anonymous mappings earlier on Windows by seeing if
the file descriptor argument to mmap() was supplied as -1. This was not
correct. The proper thing to do is check `flags & MAP_ANONYMOUS`.
The C standard states, for conversions using the d, i, b, B, o, u, x or X conversion specifiers:
> The precision specifies the minimum number of digits to appear; if
> the value being converted can be represented in fewer digits, it is
> expanded with leading zeros.
- C standard, 7.23.6.1. The fprintf function
However, cosmopolitan currently suppresses the addition of leading
zeros when the minus flag is set. This is not reflected by anything
within the C standard, meaning that behavior is incorrect.
This patch fixes this.
* Implement S conversion specifier for printf-related functions
POSIX specifies that a conversion specifier of S must be interpreted
the same way as %ls. This patch implements this.
* clang-format
---------
Co-authored-by: Gavin Hayes <gavin@computoid.com>
* Update redbean SQLite config to handle more options
This requires moving sqlite3_initialize call to open, as configuration
should be allowed before initialization is done. This call is effective
only for the first time and then no-op after that.
* Fix redbean SQLite for closing db with already finalized statements
There is a loop in cleanupdb that finalizes all vms that are associated
with that db when it's being closed. Under some circumstances (detailed
below) that loop may contain references pointing to already collected
objects, thus leading to SIGSEGV when those references are used.
This may happen with the following sequence of events ("VM" is the name
used in lsqlite and describes the same thing as "statement"):
1. A finalized statement is created (for example, by preparing an empty
string or a string with no statement that is still grammatically valid).
2. This statement goes out of scope before the DB object it's associated
with does and is garbage collected.
3. When it's garbage collected, dbvm_gc method is called, which checks
for svm->vm being not NULL.
4. Since the VM is already finalized, cleanupvm method is not called,
so the VM reference is not removed from the table of VMs tracked for
that DB.
5. When the DB is finally closed or garbage collected, all the VMs
associated with it are accessed to be finalized, including the ones that
have been garbage collected and have invalid references (thus leading
to a memory access error).
Here is an example of a stacktrace from the resulting SIGSEGV:
70000003de20 5df71a getgeneric+26
70000003fac0 5dfc7f luaH_get+111
70000003faf0 5e06c8 luaH_set+40
70000003fb20 5c5bd7 aux_rawset+55
70000003fb50 5c70cb lua_rawset+27
70000003fb60 4fa8e7 cleanupvm+71
70000003fb80 4fa988 cleanupdb+88
70000003fbc0 4fe899 db_gc+41
One way to fix this is to use userdata references (which anchor their
targets) instead of lightuserdata references (which do not), but this
would prevent the targets (VMs) from being garbage collected until the
DB itself is garbage collected, so this needs to be combined with
weakening the keys in the DB table. The code in cleanupdb to remove the
VM references is no longer needed, as this is handled by having weak keys.
The patch also switches to using close_v2, as it is intended for use
with garbage collected languages where the order in which destructors
are called is arbitrary, as is the case here.
* Remove GC collection from redbean SQLite session
The behavior of sqlite3session_delete is undefined after the DB
connection is closed, so we need to avoid calling it from gc handler.
This is an official tagged version. The 1.1 version used earlier was
informal. Formal versions will always have major.minor.patch going
forward. See https://github.com/jart/blink/tags 1.0.0 coming soon.
Python triggered the undefined behavior previously since it appears to
be posting to a semaphore owned by a different process that wasn't set
to process shared mode. The performance loss to process shared futexes
is so low and semaphores are generally used for this purpose, so it'll
be much simpler to simply not impose undefined behavior here.
Python threads are now generally working, however some parts of Python's
regression tests for threads are flaky. This is possibly due to needing
more locking primitives in Cosmo's IO system call wrappers, e.g. close.
make o//third_party/python/Lib/test/test_threading.py.runs
See #747
- enable WITH_THREAD and _POSIX_THREADS
- add headers everywhere
- breaks only two tests (faulthandler and signal)
- disabled terminal completion because it causes segfaults for some
reason (probably could not get the current thread)
This fixes a bug where the caller's timeval will be clobbered on Linux.
The Kernel ABI *always* modifies the timeout argument but POSIX says it
should be a const parameter. The wrapper now handles the difference and
sys_select() may be used if obtaining the remainder on Linux is needed.
The system call wrapper was wrongfully reinterpreting kernel data. The
examples/sysinfo.c program is now updated to show how to correctly use
what's returned.
It's been superseded by token bucket processing, does not take time
into considerations (only the number of fragments), and affects file
uploads that may require a large number of reads.
