event/MultiSocketMonitor: pass std::span to ReplaceSocketList()

Author: MaxKellermann

src/event/MultiSocketMonitor.cxx

@@ -66,27 +66,26 @@ MultiSocketMonitor::ClearSocketList() noexcept
 #ifndef _WIN32
 
 void
-MultiSocketMonitor::ReplaceSocketList(pollfd *pfds, unsigned n) noexcept
+MultiSocketMonitor::ReplaceSocketList(std::span<pollfd> pfds) noexcept
 {
 #ifdef USE_EPOLL
 	always_ready_fds.clear();
 #endif
 
-	pollfd *const end = pfds + n;
-
-	UpdateSocketList([pfds, end](SocketDescriptor fd) -> unsigned {
-		auto i = std::find_if(pfds, end, [fd](const struct pollfd &pfd){
+	UpdateSocketList([pfds](SocketDescriptor fd) -> unsigned {
+		auto i = std::find_if(pfds.begin(), pfds.end(), [fd](const struct pollfd &pfd){
 			return pfd.fd == fd.Get();
 		});
-		if (i == end)
+
+		if (i == pfds.end())
 			return 0;
 
 		return std::exchange(i->events, 0);
 	});
 
-	for (auto i = pfds; i != end; ++i)
-		if (i->events != 0)
-			AddSocket(SocketDescriptor(i->fd), i->events);
+	for (const auto &i : pfds)
+		if (i.events != 0)
+			AddSocket(SocketDescriptor(i.fd), i.events);
 }
 
 #endif

src/event/MultiSocketMonitor.hxx

@@ -12,6 +12,7 @@
 #include <cassert>
 #include <forward_list>
 #include <iterator>
+#include <span>
 
 #ifndef _WIN32
 struct pollfd;
@@ -190,7 +191,7 @@ public:
 	 *
 	 * May only be called from PrepareSockets().
 	 */
-	void ReplaceSocketList(pollfd *pfds, unsigned n) noexcept;
+	void ReplaceSocketList(std::span<pollfd> pfds) noexcept;
 #endif
 
 	/**

src/lib/alsa/NonBlock.cxx

@@ -26,7 +26,7 @@ AlsaNonBlockPcm::PrepareSockets(MultiSocketMonitor &m, snd_pcm_t *pcm)
 			throw Alsa::MakeError(count, "snd_pcm_poll_descriptors() failed");
 	}
 
-	m.ReplaceSocketList(pfds, count);
+	m.ReplaceSocketList({pfds, static_cast<std::size_t>(count)});
 	return Event::Duration(-1);
 }
 
@@ -71,7 +71,7 @@ AlsaNonBlockMixer::PrepareSockets(MultiSocketMonitor &m, snd_mixer_t *mixer) noe
 	if (count < 0)
 		count = 0;
 
-	m.ReplaceSocketList(pfds, count);
+	m.ReplaceSocketList({pfds, static_cast<std::size_t>(count)});
 	return Event::Duration(-1);
 }