Closes: #1080183

Store sockets in a dynamic array instead of a linked list.

Before:
 - Allocate: O(n)
 - Lookup: O(n)
 - Free: O(n)

After:
 - Alocate: O(n)
 - Lookup: O(1)
 - Free: O(1)

* src/core/init.c:
  * Stop forcing `LWIP_SOCKET_SELECT = 0` when `LWIP_SOCKET_OPEN_COUNT = 1`
    * `select()` won't work with sockets which number is over `FD_SETSIZE`,
      but the man page already includes a warning about it. I don't think we
      should forbid `select()` completely because of this.
* contrib/ports/unix/posixlib/lwipopts.h:
  * Stop setting `LWIP_SOCKET_SELECT` to `0`
* src/api/sockets.c:
  * Implement dynamic array logic
    * Remove `translate_socket()`, not needed anymore.
    * Use `sockets_slots_count` as the socket list capacity instead
      of `NUM_SOCKETS`
    * `alloc_socket_slots_locked()`: new method to increase sockets capacity
    * `init_socket()`: New method implementing the common socket init logic
    * `alloc_socket()`: When `LWIP_SOCKET_OPEN_COUNT = 1`, it allocates new
      slots for more sockets.

Graham Inggs authored 1 year ago and Samuel Thibault committed 1 year ago

Closes: #1062676

It's enabled in cc.h for Mac OS. Enable it there also for Linux and the Hurd.

It's unused in LwIP as far as I know.

* src/api/sockets.c:
  * lwip_poll:
    * sends UINT32_MAX as timeout to sys_arch_sem_wait
    * gracefully fails when signaled
  * lwip_select: Same changes as lwip_poll
* contrib/ports/unix/port/sys_arch.c:
  * cond_wait: waits forever when timeout == 0 or timeout == UINT32_MAX
  * sys_arch_sem_wait:
    * accepts UINT32_MAX as timeout
    * when timeout == 0, waits forever and ignore signals
    * when timeout == UINT32_MAX, waits forever and listen to signals
    * returns SYS_ARCH_INTR when signaled

* sys_arch.c: We were returning SYS_ARCH_INTR to the stack,
  but that value is not read from anywhere. This commits removes
  the logic that returns SYS_ARCH_INTR from sys_arch_sem_wait().

It was applied in 2.1.3 and tt's still needed in 2.2.0

  * patches/empty_block_last: (Closes: Bug#1055173)

Use LWIP_SOCKET_HAVE_SA_LEN instead

To match the type in glibc's socket.h