This allows to execute all adb commands with the specific -s parameter,
even if it is not provided by the user.
In practice, calling adb without -s works if there is exactly one device
connected. But some adb commands (for example "adb push" on drag & drop)
could be executed after another device is connected, so the actual
device serial must be known.
The interruptible version of the function to check process success
(sc_process_check_success_intr()) did not accept a close parameter to
avoid a race condition. But as the result, the processes were not closed
at all.
Add a close parameter, and close the process separately to avoid the
race condition.
Interrupt any blocking call on process terminated, like on
server_stop().
This allows to interrupt any blocking accept() with correct
synchronization without additional complexity.
Define server callbacks, start the server asynchronously and listen to
connection events to initialize scrcpy properly.
It will help to simplify the server code, and allows to run the UI event
loop while the server is connecting. In particular, this will allow to
receive SIGINT/Ctrl+C events during connection to interrupt immediately.
Currently, server_stop() is called from the same thread as
server_connect_to(), so interruption may never happen.
This is a step to prepare executing the server from a dedicated thread.
On Linux, socket functions are unblocked by shutdown(), but on Windows
they are unblocked by closesocket().
Expose net_interrupt() and net_close() to abstract these differences:
- net_interrupt() calls shutdown() on Linux and closesocket() on
Windows (if not already called);
- net_close() calls close() on Linux and closesocket() on Windows (if
not already called).
This simplifies the server code, and prevents a data race on close
(reported by TSAN) on Linux (but does not fix it on Windows):
WARNING: ThreadSanitizer: data race (pid=836124)
Write of size 8 at 0x7ba0000000d0 by main thread:
#0 close ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1690 (libtsan.so.0+0x359d8)
#1 net_close ../app/src/util/net.c:211 (scrcpy+0x1c76b)
#2 close_socket ../app/src/server.c:330 (scrcpy+0x19442)
#3 server_stop ../app/src/server.c:522 (scrcpy+0x19e33)
#4 scrcpy ../app/src/scrcpy.c:532 (scrcpy+0x156fc)
#5 main ../app/src/main.c:92 (scrcpy+0x622a)
Previous read of size 8 at 0x7ba0000000d0 by thread T6:
#0 recv ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:6603 (libtsan.so.0+0x4f4a6)
#1 net_recv ../app/src/util/net.c:167 (scrcpy+0x1c5a7)
#2 run_receiver ../app/src/receiver.c:76 (scrcpy+0x12819)
#3 <null> <null> (libSDL2-2.0.so.0+0x84f40)
The function sc_cond_timedwait() accepted a parameter representing the
max duration to wait, because it internally uses SDL_CondWaitTimeout().
Instead, accept a deadline, to be consistent with
pthread_cond_timedwait().
The functions SDL_malloc(), SDL_free() and SDL_strdup() were used only
because strdup() was not available everywhere.
Now that it is available, use the native version of these functions.
The current process could be waited both by run_file_handler() and
file_handler_stop().
To avoid the race condition, wait the process without closing, then
close with mutex locked.
There were two versions: process_wait() and process_wait_noclose().
Expose a single version with a flag (it was already implemented that way
internally).
The function process_wait() returned a bool (true if the process
terminated successfully) and provided the exit code via an output
parameter exit_code.
But the returned value was always equivalent to exit_code == 0, so just
return the exit code instead.
On Linux, waitpid() both waits for the process to terminate and reaps it
(closes its handle). On Windows, these actions are separated into
WaitForSingleObject() and CloseHandle().
Expose these actions separately, so that it is possible to send a signal
to a process while waiting for its termination without race condition.
This allows to wait for server termination normally, but kill the
process without race condition if it is not terminated after some delay.
