load libcurl at runtime (#33)

* load libcurl at runtime

* add warning to file tab if curl cant be loaded

CMakeLists.txt

@@ -35,6 +35,7 @@ if(BUILD_OUT_OF_TREE)
 		src/headers/advanced-scene-switcher.hpp
 		src/headers/switcher-data-structs.hpp
 		src/headers/utility.hpp
+		src/headers/curl-helper.hpp
 		)
 
 	set(advanced-scene-switcher_SOURCES
@@ -55,6 +56,7 @@ if(BUILD_OUT_OF_TREE)
 		src/pause-switch.cpp
 		src/random.cpp
 		src/time-switch.cpp
+		src/curl-helper.cpp
 		)
 
 	set(advanced-scene-switcher_UI
@@ -105,8 +107,7 @@ if(BUILD_OUT_OF_TREE)
 		${LIBOBS_LIB}
 		${LIBOBS_FRONTEND_API_LIB}
 		Qt5::Core
-		Qt5::Widgets
-		${LIBCURL_LIBRARIES})
+		Qt5::Widgets)
 
 	# Additional commands to install the module in the correct place.
 	# Find all the translation files so we can copy them to the correct
@@ -167,6 +168,7 @@ else ()
 		src/headers/advanced-scene-switcher.hpp
 		src/headers/switcher-data-structs.hpp
 		src/headers/utility.hpp
+		src/headers/curl-helper.hpp
 		)
 
 	set(advanced-scene-switcher_SOURCES
@@ -187,6 +189,7 @@ else ()
 		src/pause-switch.cpp
 		src/random.cpp
 		src/time-switch.cpp
+		src/curl-helper.cpp
 		)
 
 	set(advanced-scene-switcher_UI
@@ -227,8 +230,7 @@ else ()
 		${advanced-scene-switcher_PLATFORM_LIBS}
 		obs-frontend-api
 		Qt5::Widgets
-		libobs
-		${LIBCURL_LIBRARIES})
+		libobs)
 
 	install_obs_plugin(advanced-scene-switcher data)
 endif()

forms/advanced-scene-switcher.ui

@@ -2404,7 +2404,7 @@
       <attribute name="title">
        <string notr="true">File</string>
       </attribute>
-      <layout class="QVBoxLayout" name="verticalLayout_9">
+      <layout class="QVBoxLayout" name="verticalLayout_6">
        <item>
         <layout class="QHBoxLayout" name="horizontalLayout_14">
          <item>
@@ -2537,6 +2537,22 @@
          </property>
         </widget>
        </item>
+       <item>
+        <widget class="QLabel" name="libcurlWarning">
+         <property name="enabled">
+          <bool>true</bool>
+         </property>
+         <property name="font">
+          <font>
+           <weight>75</weight>
+           <bold>true</bold>
+          </font>
+         </property>
+         <property name="text">
+          <string>Failed to load libcurl! Accesssing remote files will not be possible!</string>
+         </property>
+        </widget>
+       </item>
        <item>
         <widget class="QPlainTextEdit" name="fileTextEdit"/>
        </item>

src/advanced-scene-switcher.cpp

@@ -16,6 +16,7 @@
 #include "headers/switcher-data-structs.hpp"
 #include "headers/advanced-scene-switcher.hpp"
 #include "headers/utility.hpp"
+#include "headers/curl-helper.hpp"
 
 SwitcherData *switcher = nullptr;
 
@@ -342,6 +343,13 @@ void SwitcherData::Stop()
  ********************************************************************************/
 extern "C" void FreeSceneSwitcher()
 {
+	if (loaded_curl_lib) {
+		if (switcher->curl && f_curl_cleanup)
+			f_curl_cleanup(switcher->curl);
+		delete loaded_curl_lib;
+		loaded_curl_lib = nullptr;
+	}
+
 	delete switcher;
 	switcher = nullptr;
 }
@@ -406,6 +414,10 @@ extern "C" void InitSceneSwitcher()
 
 	switcher = new SwitcherData;
 
+	if (loadCurl() && f_curl_init) {
+		switcher->curl = f_curl_init();
+	}
+
 	auto cb = []() {
 		QMainWindow *window =
 			(QMainWindow *)obs_frontend_get_main_window();

src/curl-helper.cpp

@@ -0,0 +1,65 @@
+#include <QDir>
+#include <QFileInfo>
+#include <curl/curl.h>
+#include <obs.hpp>
+
+#include "headers/curl-helper.hpp"
+
+initFunction f_curl_init = nullptr;
+setOptFunction f_curl_setopt = nullptr;
+performFunction f_curl_perform = nullptr;
+cleanupFunction f_curl_cleanup = nullptr;
+
+QLibrary *loaded_curl_lib = nullptr;
+
+bool resolveCurl()
+{
+	f_curl_init = (initFunction)loaded_curl_lib->resolve("curl_easy_init");
+	f_curl_setopt = (setOptFunction)loaded_curl_lib->resolve("curl_easy_setopt");
+	f_curl_perform =
+		(performFunction)loaded_curl_lib->resolve("curl_easy_perform");
+	f_curl_cleanup =
+		(cleanupFunction)loaded_curl_lib->resolve("curl_easy_cleanup");
+
+	if (f_curl_init && f_curl_setopt && f_curl_perform && f_curl_cleanup) {
+		blog(LOG_INFO, "curl loaded successfully");
+		return true;
+	}
+
+	blog(LOG_INFO, "curl symbols not resolved");
+	return false;
+}
+
+bool loadCurl()
+{
+	QStringList locations;
+	locations << QDir::currentPath();
+#if defined(__linux__) || defined(__APPLE__)
+	locations << "/usr/lib";
+	locations << "/usr/local/lib";
+	locations << "/usr/lib/x86_64-linux-gnu";
+	locations << "/usr/local/opt/curl/lib";
+#endif
+
+	for (QString path : locations) {
+		blog(LOG_INFO, "trying '%s'", path.toUtf8().constData());
+		QFileInfo libPath(QDir(path).absoluteFilePath(CURL_LIBRARY_NAME));
+
+		if (libPath.exists() && libPath.isFile()) {
+			QString libFilePath = libPath.absoluteFilePath();
+			blog(LOG_INFO, "found curl library at '%s'",
+			     libFilePath.toUtf8().constData());
+
+			loaded_curl_lib = new QLibrary(libFilePath, nullptr);
+			if (resolveCurl())
+				return true;
+			else {
+				delete loaded_curl_lib;
+				loaded_curl_lib = nullptr;
+			}
+		}
+	}
+
+	blog(LOG_ERROR, "can't find the curl library");
+	return false;
+}

src/file-switch.cpp

@@ -5,6 +5,7 @@
 #include <curl/curl.h>
 
 #include "headers/advanced-scene-switcher.hpp"
+#include "headers/curl-helper.hpp"
 
 #define LOCAL_FILE_IDX 0
 #define REMOTE_FILE_IDX 1
@@ -124,17 +125,13 @@ static size_t WriteCallback(void *contents, size_t size, size_t nmemb,
 
 std::string getRemoteData(std::string &url)
 {
-	CURL *curl;
-	CURLcode res;
 	std::string readBuffer;
 
-	curl = curl_easy_init();
-	if (curl) {
-		curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
-		curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
-		curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);
-		res = curl_easy_perform(curl);
-		curl_easy_cleanup(curl);
+	if (switcher->curl && f_curl_setopt && f_curl_perform) {
+		f_curl_setopt(switcher->curl, CURLOPT_URL, url.c_str());
+		f_curl_setopt(switcher->curl, CURLOPT_WRITEFUNCTION, WriteCallback);
+		f_curl_setopt(switcher->curl, CURLOPT_WRITEDATA, &readBuffer);
+		f_curl_perform(switcher->curl);
 	}
 	return readBuffer;
 }
@@ -447,6 +444,9 @@ void SceneSwitcher::setupFileTab()
 		"Note that the scene switcher will try to access the remote location every " +
 		QString::number(switcher->interval) + "ms");
 
+	if (switcher->curl)
+		ui->libcurlWarning->setVisible(false);
+
 	for (auto &s : switcher->fileSwitches) {
 		std::string sceneName = GetWeakSourceName(s.scene);
 		std::string transitionName = GetWeakSourceName(s.transition);

src/headers/curl-helper.hpp

@@ -0,0 +1,26 @@
+#pragma once
+#include <curl/curl.h>
+#include <QLibrary>
+
+#if defined(WIN32)
+#define CURL_LIBRARY_NAME "libcurl.dll"
+#elif __APPLE__
+#define CURL_LIBRARY_NAME "libcurl.4.dylib"
+#else
+#define CURL_LIBRARY_NAME "libcurl.so.4"
+#endif
+
+typedef CURL *(*initFunction)(void);
+typedef CURLcode (*setOptFunction)(CURL *, CURLoption, ...);
+typedef CURLcode (*performFunction)(CURL *);
+typedef void (*cleanupFunction)(CURL *);
+
+extern initFunction f_curl_init;
+extern setOptFunction f_curl_setopt;
+extern performFunction f_curl_perform;
+extern cleanupFunction f_curl_cleanup;
+
+extern QLibrary *loaded_curl_lib;
+
+bool resolveCurl();
+bool loadCurl();

src/headers/switcher-data-structs.hpp

@@ -8,6 +8,7 @@
 #include <fstream>
 #include <QDateTime>
 #include <QThread>
+#include <curl/curl.h>
 #include "utility.hpp"
 
 #define DEFAULT_INTERVAL 300
@@ -309,6 +310,7 @@ struct SwitcherData {
 	FileIOData fileIO;
 	IdleData idleData;
 	std::vector<FileSwitch> fileSwitches;
+	CURL *curl = nullptr;
 
 	std::vector<ExecutableSceneSwitch> executableSwitches;