Support compile for Android and compatible to API-21

CMakeLists.txt

@@ -262,6 +262,21 @@ else()
             message(STATUS "sendmmsg is missing. Send performance will be reduced")
         endif()
 
+        check_function_exists(recvmmsg HAS_RECVMMSG)
+        if(NOT HAS_RECVMMSG)
+            message(STATUS "recvmmsg is missing. Receive performance will be reduced")
+        endif()
+
+        check_function_exists(epoll_create1 HAS_EPOLL_CREATE1)
+        if(NOT HAS_EPOLL_CREATE1)
+            message(STATUS "epoll_create1 is missing.")
+        endif()
+
+        check_function_exists(pthread_condattr_setclock HAS_PTHREAD_SET_CLOCK)
+        if(NOT HAS_PTHREAD_SET_CLOCK)
+            message(STATUS "pthread_condattr_setclock is missing.")
+        endif()
+
         # Error if flags are missing in CI
         if(QUIC_CI AND NOT QUIC_SKIP_CI_CHECKS)
             if (NOT HAS_UDP_SEGMENT)
@@ -295,6 +310,15 @@ else()
     if (HAS_SENDMMSG)
         list(APPEND QUIC_COMMON_DEFINES HAS_SENDMMSG)
     endif()
+    if (HAS_RECVMMSG)
+        list(APPEND QUIC_COMMON_DEFINES HAS_RECVMMSG)
+    endif()
+    if (HAS_EPOLL_CREATE1)
+        list(APPEND QUIC_COMMON_DEFINES HAS_EPOLL_CREATE1)
+    endif()
+    if (HAS_PTHREAD_SET_CLOCK)
+        list(APPEND QUIC_COMMON_DEFINES HAS_PTHREAD_SET_CLOCK)
+    endif()
     if (HAS__SC_PHYS_PAGES)
          list(APPEND QUIC_COMMON_DEFINES HAS__SC_PHYS_PAGES)
     endif()

src/inc/quic_platform_posix.h

@@ -776,8 +776,10 @@ CxPlatEventInitialize(
     Result = pthread_condattr_init(&Attr);
     CXPLAT_FRE_ASSERT(Result == 0);
 #if defined(CX_PLATFORM_LINUX)
+#if defined(HAS_PTHREAD_SET_CLOCK)
     Result = pthread_condattr_setclock(&Attr, CLOCK_MONOTONIC);
     CXPLAT_FRE_ASSERT(Result == 0);
+#endif // HAS_PTHREAD_SET_CLOCK
 #endif // CX_PLATFORM_LINUX
     Result = pthread_cond_init(&Event->Cond, &Attr);
     CXPLAT_FRE_ASSERT(Result == 0);
@@ -1028,7 +1030,11 @@ CxPlatEventQInitialize(
     _Out_ CXPLAT_EVENTQ* queue
     )
 {
+#ifdef HAS_EPOLL_CREATE1
     return (*queue = epoll_create1(EPOLL_CLOEXEC)) != -1;
+#else
+    return (*queue = epoll_create(32000)) != -1;
+#endif
 }
 
 inline

src/platform/datapath_epoll.c

@@ -1849,13 +1849,24 @@ CxPlatSocketReceiveCoalesced(
         RecvIov.iov_base = (char*)IoBlock + DatapathPartition->Datapath->RecvBlockBufferOffset;
         RecvIov.iov_len = CXPLAT_LARGE_IO_BUFFER_SIZE;
 
-        int Ret =
-            recvmmsg(
+        int Ret = 0;
+#ifdef HAS_RECVMMSG
+        Ret = recvmmsg(
                 SocketContext->SocketFd,
                 &RecvMsgHdr,
                 1,
                 0,
                 NULL);
+#else
+        Ret = recvmsg(
+                SocketContext->SocketFd,
+                &RecvMsgHdr.msg_hdr,
+                0);
+        if (Ret > 0) {
+            RecvMsgHdr.msg_len = Ret;
+            Ret = 1;
+        }
+#endif
         if (Ret < 0) {
             if (errno != EAGAIN && errno != EWOULDBLOCK) {
                 QuicTraceEvent(
@@ -1925,13 +1936,24 @@ CxPlatSocketReceiveMessages(
             RecvIov[i].iov_len = CXPLAT_SMALL_IO_BUFFER_SIZE;
         }
 
-        int Ret =
-            recvmmsg(
+        int Ret = 0;
+#ifdef HAS_RECVMMSG
+        Ret = recvmmsg(
                 SocketContext->SocketFd,
                 RecvMsgHdr,
                 (int)CXPLAT_MAX_IO_BATCH_SIZE,
                 0,
                 NULL);
+#else
+        Ret = recvmsg(
+                SocketContext->SocketFd,
+                &RecvMsgHdr[0].msg_hdr,
+                0);
+        if (Ret > 0) {
+            RecvMsgHdr[0].msg_len = Ret;
+            Ret = 1;
+        }
+#endif
         if (Ret < 0) {
             if (errno != EAGAIN && errno != EWOULDBLOCK) {
                 QuicTraceEvent(

src/platform/platform_posix.c

@@ -479,7 +479,11 @@ CxPlatGetAbsoluteTime(
     CxPlatZeroMemory(Time, sizeof(struct timespec));
 
 #if defined(CX_PLATFORM_LINUX)
+#if defined(HAS_PTHREAD_SET_CLOCK)
     ErrorCode = clock_gettime(CLOCK_MONOTONIC, Time);
+#else
+    ErrorCode = clock_gettime(CLOCK_REALTIME, Time);
+#endif
 #elif defined(CX_PLATFORM_DARWIN)
     //
     // timespec_get is used on darwin, as CLOCK_MONOTONIC isn't actually