We avoid the problem by using poll(2).
On systems without poll(2) (older bsd-ish systems, and win32), we emulate
poll(2) using select(2) and check for valid descriptors before attempting
to access them via the descriptor sets.
If an out-of-range descriptor is detected, an E_WARNING is raised suggesting
that PHP should be recompiled with a larger FD_SETSIZE (and also with a
suggested value).
Most uses of select(2) in the source are to poll a single descriptor, so
a couple of handy wrapper functions have been added to make this easier.
A configure option --enable-fd-setsize has been added to both the unix and
win32 builds; on unix we default to 16384 and on windows we default to 256.
Windows FD_SETSIZE imposes a limit on the maximum number of descriptors that
can be select()ed at once, whereas the unix FD_SETSIZE limit is based on the
highest numbered descriptor; 256 should be plenty for PHP scripts under windows
(the default OS setting is 64).
The win32 specific parts are untested; will do that now.
- This solves alot of platform compatibility problems
- The possible security issue of allocating an incredibly large vector
pool is prevented
- They are of little to no benefit in a high level language
- 99% of all things done with these functions can be done using
sendto/recvfrom
There was a memory leak in the error handling system on win32, that this patch
circumvented (by preventing the errors (EAGAIN mesages) from being generated).
# I must have forgotten to remove this when I fixed the leak
was occurring in the error reporting system. The reason why sleepex appeared
to be working was because it suppressed EWOULDBLOCK errors in the example
(which was non-blocking)
@Fix win32 memory leak in /ext/sockets that would occur on any error condition
@Fix host resolution error messages on win32
because it does not include <sys/socket.h> which is necessary
for the definition of struct msghdr. This include file is not
part of ac_includes_default.
Regardless, AC_CHECK_MEMBER is a autoconf-2.5x macro and thus we
expand it here for 2.13 compatibility.
- Force fourth argument to be passed by reference
- Since the argument is modified there is no need to force it to be an array
since it's destroyed anyway
- Only modify the argument if socketpair() was successfully
- Fix string modified for error message message
- Set global last_error when socketpair() fails
@Fixed a bug in socket_select() that could cause unexpected behavior when using a statement
@ like $w=$e=array($sock);
@This change unfortunately prevents the use of constant values(NULL) for the socket array paramaters.
@Instead use a temporary variable or an expression with the leftmost member being a temporary variable.
@ ex. socket_select($w, $r, $e=NULL, 10);
Also fix small memory leak.
- Set the global 'last_error' explicitely for functions which can't return an
error withing a single socket context (socket_create and socket_select)
- Modified socket_last_error() to return global modules last
error if no socket resource is given
- Added a couple of more E_WARNING messages in case something
goes foobar so the user isn't left alone in the dark.
Fixed bug where socket_select was not producing an error message on error
Fixed bug where -1 was getting returned instead of FALSE in socket_recv(),
socket_send(), socket_sendto(), and socket_select()
Redesigned socket_recv() as outlined on php-dev
Modified socket_last_error() to no longer clear the error
Added socket_clear_error()
Fixed socket_set_nonblock()
Added socket_set_block()
Fixed a proto
Saved 1 byte of RAM : )
Abstracted string -> ipv4 value conversion which unifies all functions
Standardized Host Lookups
Fixed Broken host error values
Fixed error detection in sendmsg
Added some safety struct zeroing
Modified bind to consitentlyy use sockaddr_storage(not just for AF_UNIX)
#Note this could potentially break the build on other platforms, as I have
#not tested them yet (Will soon though)