client API: remove SIGPIPE overriding code

This workaround prevented that libmpv users could accidentally crash
when the SIGPIPE signal was triggered by FFmpeg's OpenSSL/GnuTLS usage.
But it also modifies the global signal handler state, so remove it now
that this workaround is not required anymore.

DOCS/client-api-changes.rst

@@ -37,6 +37,8 @@ API changes
           instead of "no-video=" you should set "video=no".
         - be much more permissive what API calls are allowed before
           mpv_initialize().
+        - do not override the SIGPIPE signal handler anymore. This was done as
+          workaround for the FFmpeg TLS code, which has been fixed long ago.
  --- mpv 0.19.0 ---
  1.22   - add stream_cb API for custom protocols
  --- mpv 0.18.1 ---

input/ipc-unix.c

@@ -20,6 +20,7 @@
 #include <unistd.h>
 
 #include <poll.h>
+#include <signal.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
@@ -97,6 +98,11 @@ static void *client_thread(void *p)
 {
     pthread_detach(pthread_self());
 
+    // We don't use MSG_NOSIGNAL because the moldy fruit OS doesn't support it.
+    struct sigaction sa = { .sa_handler = SIG_IGN, .sa_flags = SA_RESTART };
+    sigfillset(&sa.sa_mask);
+    sigaction(SIGPIPE, &sa, NULL);
+
     int rc;
 
     struct client_arg *arg = p;

libmpv/client.h

@@ -135,10 +135,6 @@ extern "C" {
  *   (used through libass), ALSA, FFmpeg, and possibly more.
  * - The FPU precision must be set at least to double precision.
  * - On Windows, mpv will call timeBeginPeriod(1).
- * - On UNIX, every mpv_initialize() call will block SIGPIPE. This is done
- *   because FFmpeg makes unsafe use of OpenSSL and GnuTLS, which can raise
- *   this signal under certain circumstances. Once these libraries (or FFmpeg)
- *   are fixed, libmpv will not block the signal anymore.
  * - On memory exhaustion, mpv will kill the process.
  *
  * Encoding of filenames

player/main.c

@@ -22,7 +22,6 @@
 #include <assert.h>
 #include <string.h>
 #include <pthread.h>
-#include <signal.h>
 
 #include "config.h"
 #include "mpv_talloc.h"
@@ -514,12 +513,6 @@ int mp_initialize(struct MPContext *mpctx, char **options)
     if (opts->w32_priority > 0)
         SetPriorityClass(GetCurrentProcess(), opts->w32_priority);
 #endif
-#ifndef _WIN32
-    // Deal with OpenSSL and GnuTLS not using MSG_NOSIGNAL.
-    struct sigaction sa = { .sa_handler = SIG_IGN, .sa_flags = SA_RESTART };
-    sigfillset(&sa.sa_mask);
-    sigaction(SIGPIPE, &sa, NULL);
-#endif
 
     prepare_playlist(mpctx, mpctx->playlist);