[posix-app] fix write in daemon mode (#3576)

In daemon mode, UART write should be processed even when no client
is connected. This commit writes UART to STDERR in such situation.

* add test for daemon mode
* remove useless code for UART restore
* fix a typo of assert
* set FD_CLOEXEC flag to better support reset.

.travis.yml

@@ -57,6 +57,9 @@ matrix:
     - env: BUILD_TARGET="posix-app-pty" VERBOSE=1
       os: linux
       compiler: gcc
+    - env: BUILD_TARGET="posix-app-pty" VERBOSE=1 DAEMON=1
+      os: linux
+      compiler: gcc
     - env: BUILD_TARGET="android-build" VERBOSE=1
       os: linux
       python: "2.7"

.travis/check-posix-app-pty

@@ -39,13 +39,14 @@ at_exit() {
     EXIT_CODE=$?
 
     sudo killall expect || true
+    killall ot-ctl || true
+    killall ot-daemon || true
     killall socat || true
 
     exit $EXIT_CODE
 }
 
 build() {
-    ./bootstrap
     COVERAGE=1 make -f examples/Makefile-posix
     COVERAGE=1 make -f src/posix/Makefile-posix PLATFORM_NETIF=1 PLATFORM_UDP=1
 }
@@ -70,9 +71,17 @@ check() {
 
     RADIO_NCP_PATH="$(pwd)/$(ls output/*linux*/bin/ot-ncp-radio)"
     $RADIO_NCP_PATH 1 > $RADIO_PTY < $RADIO_PTY &
-    OT_CLI_PATH="$(pwd)/$(ls output/posix/*linux*/bin/ot-cli)"
-    sudo expect <<EOF > $OT_OUTPUT &
-spawn $OT_CLI_PATH ${OT_NCP_PATH} ${CORE_PTY}
+
+    if [[ "${DAEMON}" = 1 ]]; then
+        sudo "$(pwd)/$(ls output/posix/*linux*/bin/ot-daemon)" ${OT_NCP_PATH} ${CORE_PTY} &
+        sleep 1
+        OT_CLI_CMD="$(pwd)/$(ls output/posix/*linux*/bin/ot-ctl)"
+    else
+        OT_CLI_CMD="$(pwd)/$(ls output/posix/*linux*/bin/ot-cli) ${OT_NCP_PATH} ${CORE_PTY}"
+    fi
+
+    sudo expect <<EOF > "${OT_OUTPUT}" &
+spawn ${OT_CLI_CMD}
 send "panid 0xface\r\n"
 expect "Done"
 send "ifconfig up\r\n"

.travis/script.sh

@@ -433,6 +433,7 @@ build_samr21() {
 }
 
 [ $BUILD_TARGET != posix-app-pty ] || {
+    ./bootstrap
     .travis/check-posix-app-pty || die
 }
 

src/posix/platform/misc.c

@@ -48,7 +48,6 @@ void otPlatReset(otInstance *aInstance)
     OT_UNUSED_VARIABLE(aInstance);
 
     otSysDeinit();
-    platformUartRestore();
 
     longjmp(gResetJump, 1);
     assert(false);

src/posix/platform/platform-posix.h

@@ -263,12 +263,6 @@ void platformNetifUpdateFdSet(fd_set *aReadFdSet, fd_set *aWriteFdSet, fd_set *a
  */
 void platformNetifProcess(const fd_set *aReadFdSet, const fd_set *aWriteFdSet, const fd_set *aErrorFdSet);
 
-/**
- * This function restores the Uart.
- *
- */
-void platformUartRestore(void);
-
 /**
  * This function initialize simulation.
  *

src/posix/platform/uart.c

@@ -46,6 +46,7 @@
 #include <openthread/platform/uart.h>
 
 #include "code_utils.h"
+#include "common/code_utils.hpp"
 
 #define OPENTHREAD_POSIX_APP_SOCKET_LOCK OPENTHREAD_POSIX_APP_SOCKET_BASENAME ".lock"
 
@@ -58,9 +59,16 @@ static int sSessionSocket = -1;
 static const uint8_t *sWriteBuffer = NULL;
 static uint16_t       sWriteLength = 0;
 
-void platformUartRestore(void)
+#if OPENTHREAD_ENABLE_POSIX_APP_DAEMON
+static void set_flag_cloexec(int a_fd)
 {
+    int ret = fcntl(a_fd, F_GETFD, 0);
+    VerifyOrDie(ret != -1, OT_EXIT_FAILURE);
+    ret |= FD_CLOEXEC;
+    ret = fcntl(a_fd, F_SETFD, ret);
+    VerifyOrDie(ret != -1, OT_EXIT_FAILURE);
 }
+#endif // OPENTHREAD_ENABLE_POSIX_APP_DAEMON
 
 otError otPlatUartEnable(void)
 {
@@ -70,12 +78,15 @@ otError otPlatUartEnable(void)
     int                ret;
 
     sUartSocket = socket(AF_UNIX, SOCK_STREAM, 0);
+
     if (sUartSocket == -1)
     {
         perror("socket");
         exit(OT_EXIT_FAILURE);
     }
 
+    set_flag_cloexec(sUartSocket);
+
     sUartLock = open(OPENTHREAD_POSIX_APP_SOCKET_LOCK, O_CREAT | O_RDONLY, 0600);
 
     if (sUartLock == -1)
@@ -84,6 +95,8 @@ otError otPlatUartEnable(void)
         exit(OT_EXIT_FAILURE);
     }
 
+    set_flag_cloexec(sUartLock);
+
     if (flock(sUartLock, LOCK_EX | LOCK_NB) == -1)
     {
         perror("flock");
@@ -95,7 +108,7 @@ otError otPlatUartEnable(void)
     (void)unlink(OPENTHREAD_POSIX_APP_SOCKET_NAME);
 
     sockname.sun_family = AF_UNIX;
-    assert(sizeof(OPENTHREAD_POSIX_APP_SOCKET_NAME) < sizeof(sockname.sun_path), "socket name too long");
+    assert(sizeof(OPENTHREAD_POSIX_APP_SOCKET_NAME) < sizeof(sockname.sun_path));
     strncpy(sockname.sun_path, OPENTHREAD_POSIX_APP_SOCKET_NAME, sizeof(sockname.sun_path) - 1);
 
     ret = bind(sUartSocket, (const struct sockaddr *)&sockname, sizeof(struct sockaddr_un));
@@ -219,6 +232,13 @@ void platformUartProcess(const fd_set *aReadFdSet, const fd_set *aWriteFdSet, co
         sSessionSocket = accept(sUartSocket, NULL, NULL);
     }
 
+    if (sSessionSocket == -1 && sWriteBuffer != NULL)
+    {
+        IgnoreReturnValue(write(STDERR_FILENO, sWriteBuffer, sWriteLength));
+        sWriteBuffer = NULL;
+        sWriteLength = 0;
+    }
+
     otEXPECT(sSessionSocket != -1);
 
     if (FD_ISSET(sSessionSocket, aErrorFdSet))