add http_client library, using libcurl

take out common http entities to http_common dir

libs/http_client/curl_thread_pool_p.cpp

@@ -0,0 +1,75 @@
+
+#include "curl_thread_pool_p.h"
+
+#include "pihttpclient.h"
+#include "pitime.h"
+
+
+CurlThreadPool::CurlThreadPool() {
+	piForTimes(10) {
+		auto * t = new PIThread([this]() { threadFunc(); }, true);
+		threads << t;
+	}
+}
+
+
+CurlThreadPool::~CurlThreadPool() {
+	exiting = true;
+	for (auto * t: threads)
+		t->stop();
+	{
+		auto cr = clients.getRef();
+		for (auto c: *cr)
+			c->abort();
+	}
+	sem.release(threads.size());
+	for (auto * t: threads) {
+		t->waitForFinish();
+		t->setDebug(false);
+		t->terminate();
+	}
+	piDeleteAllAndClear(threads);
+	{
+		auto cr = clients.getRef();
+		for (auto c: *cr)
+			delete c;
+	}
+}
+
+
+void CurlThreadPool::threadFunc() {
+	if (exiting) return;
+	// piCout << "threadFuncl w ...";
+	sem.acquire();
+	// piCout << "threadFuncl wdone";
+	if (exiting) return;
+	PIHTTPClient * c = nullptr;
+	{
+		auto cr = clients.getRef();
+		if (cr->isEmpty()) return;
+		c = cr->dequeue();
+		// piCout << "threadFuncl get c";
+	}
+	// piCout << "threadFuncl proc c";
+	procClient(c);
+	// piCout << "threadFuncl end";
+}
+
+
+void CurlThreadPool::procClient(PIHTTPClient * c) {
+	if (c->init()) c->perform();
+	delete c;
+}
+
+
+void CurlThreadPool::registerClient(PIHTTPClient * c) {
+	clients.getRef()->enqueue(c);
+	sem.release();
+	// piCout << "registerClient";
+}
+
+
+CurlThreadPool * CurlThreadPool::instance() {
+	static CurlThreadPool ret;
+	return &ret;
+}