Add workaround to see debug messages from native code in android service

libretroshare/src/libretroshare.pro

@@ -910,4 +910,6 @@ android-g++ {
     INCLUDEPATH += $$NDK_TOOLCHAIN_PATH/sysroot/usr/include
     DEPENDPATH += $$NDK_TOOLCHAIN_PATH/sysroot/usr/include
     PRE_TARGETDEPS += $$NDK_TOOLCHAIN_PATH/sysroot/usr/lib/libcrypto.a
+
+    HEADERS += util/androiddebug.h
 }

libretroshare/src/util/androiddebug.h

@@ -0,0 +1,117 @@
+#pragma once
+/*
+ * Redirect plain stdout and stderr to Android debug
+ * Copyright (C) 2016  Gioacchino Mazzurco <gio@eigenlab.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+// Inspired by: https://codelab.wordpress.com/2014/11/03/how-to-use-standard-output-streams-for-logging-in-android-apps/
+
+#include <stdio.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <fcntl.h>           // for O_NONBLOCK
+#include <android/log.h>
+#include <atomic>
+#include <string>
+
+/**
+ * On Android stdout and stderr of native code is discarded, instancing this
+ * class at the beginning of the main of your program to get them (stdout and
+ * stderr) on logcat output.
+ */
+class AndroidStdIOCatcher
+{
+public:
+	AndroidStdIOCatcher(const std::string& dTag = "RetroShare",
+	                    android_LogPriority stdout_pri = ANDROID_LOG_INFO,
+	                    android_LogPriority stderr_pri = ANDROID_LOG_ERROR) :
+	    tag(dTag), cout_pri(stdout_pri), cerr_pri(stderr_pri), should_stop(false)
+	{
+		// make stdout line-buffered
+		//setvbuf(stdout, 0, _IOLBF, 0);
+
+		// make stdout and stderr unbuffered
+		setvbuf(stdout, 0, _IONBF, 0);
+		setvbuf(stderr, 0, _IONBF, 0);
+
+		// create the pipes and redirect stdout and stderr
+		pipe2(pout_fd, O_NONBLOCK);
+		dup2(pout_fd[1], STDOUT_FILENO);
+
+		pipe2(perr_fd, O_NONBLOCK);
+		dup2(perr_fd[1], STDERR_FILENO);
+
+		// spawn the logging thread
+		pthread_create(&thr, 0, thread_func, this);
+		pthread_detach(thr);
+	}
+
+	~AndroidStdIOCatcher()
+	{
+		should_stop = true;
+		pthread_join(thr, NULL);
+	}
+
+private:
+	const std::string tag;
+	const android_LogPriority cout_pri;
+	const android_LogPriority cerr_pri;
+
+	int pout_fd[2];
+	int perr_fd[2];
+	pthread_t thr;
+	std::atomic<bool> should_stop;
+
+	static void *thread_func(void* instance)
+	{
+		__android_log_write(ANDROID_LOG_INFO, "RetroShare", "Android debugging start");
+
+		AndroidStdIOCatcher &i = *static_cast<AndroidStdIOCatcher*>(instance);
+
+		std::string out_buf;
+		std::string err_buf;
+
+		while (!i.should_stop)
+		{
+			for(char c; read(i.pout_fd[0], &c, 1) == 1;)
+			{
+				out_buf += c;
+				if(c == '\n')
+				{
+					__android_log_write(i.cout_pri, i.tag.c_str(), out_buf.c_str());
+					out_buf.clear();
+				}
+			}
+
+			for(char c; read(i.perr_fd[0], &c, 1) == 1;)
+			{
+				err_buf += c;
+				if(c == '\n')
+				{
+					__android_log_write(i.cerr_pri, i.tag.c_str(), err_buf.c_str());
+					err_buf.clear();
+				}
+			}
+
+			usleep(10000);
+		}
+
+		__android_log_write(ANDROID_LOG_INFO, "RetroShare", "Android debugging stop");
+
+		return NULL;
+	}
+};
+

retroshare-android-service/src/service.cpp

@@ -21,6 +21,7 @@
 
 #ifdef __ANDROID__
 #	include <QtAndroidExtras>
+#	include "util/androiddebug.h"
 #endif
 
 #include "retroshare/rsinit.h"
@@ -28,10 +29,15 @@
 #include "api/ApiServerLocal.h"
 #include "api/RsControlModule.h"
 
+
 using namespace resource_api;
 
 int main(int argc, char *argv[])
 {
+#ifdef __ANDROID__
+	AndroidStdIOCatcher dbg; (void) dbg;
+#endif
+
 	QCoreApplication a(argc, argv);
 	ApiServer api;
 	RsControlModule ctrl_mod(argc, argv, api.getStateTokenServer(), &api, true);