multi-threading

Makefile

@@ -1,8 +1,12 @@
-SRCS = src/BBBParser.cc src/SourceFile.cc src/toolchain.cc src/globals.cc src/sys.cc src/main.cc
-HDRS = src/BBBParser.h src/SourceFile.h src/toolchain.h src/globals.h src/sys.h src/parallel.h
+SRCS = \
+	src/BBBParser.cc src/SourceFile.cc src/toolchain.cc src/globals.cc \
+	src/sys.cc src/parallel.cc src/main.cc
+HDRS = src/BBBParser.h src/SourceFile.h src/toolchain.h src/globals.h \
+	src/sys.h src/parallel.h
 BUILD = build
 OBJS = $(patsubst %,$(BUILD)/%.o,$(SRCS))
 CFLAGS = -g -Wall -Wextra -Wno-unused-parameter
+LDLIBS = -lpthread
 
 $(BUILD)/%.cc.o: %.cc $(HDRS)
 	@mkdir -p $(@D)

src/SourceFile.cc

@@ -164,6 +164,8 @@ bool SourceFile::needsRecompile(const std::string &outDir) const {
 }
 
 void SourceFile::compile(const std::string &outDir) const {
+	// TODO: Send this as a message to some printer thread instead,
+	// because this happens in multiple threads
 	std::cerr << "Compile " << objectPath(outDir) << '\n';
 	toolchain::compile(compileFlags(), type_, dir_, name_, outDir);
 

src/parallel.cc

@@ -1,7 +1,41 @@
 #include "parallel.h"
 
 #include <thread>
+#include <vector>
+#include <mutex>
+#include <condition_variable>
+
+namespace parallel {
+
+void runJobs(
+		int jobs, const std::vector<void *> &elems,
+		std::function<void(void *)> func) {
+	int currentJobs = 0;
+	std::mutex mut;
+	std::unique_lock<std::mutex> lock(mut);
+	std::condition_variable cond;
+
+	for (void *elem: elems) {
+		cond.wait(lock, [&] { return currentJobs < jobs; });
+
+		currentJobs += 1;
+		std::thread thread([elem, jobs, &currentJobs, &mut, &cond, &func] {
+			func(elem);
+
+			mut.lock();
+			currentJobs -= 1;
+			mut.unlock();
+			cond.notify_one();
+		});
+
+		thread.detach();
+	}
+
+	cond.wait(lock, [&] { return currentJobs == 0; });
+}
 
 int coreCount() {
 	return std::thread::hardware_concurrency();
 }
+
+}

src/parallel.h

@@ -1,19 +1,32 @@
 #pragma once
 
-#include <thread>
+#include <functional>
+#include <vector>
 
 namespace parallel {
 
+void runJobs(
+		int jobs, const std::vector<void *> &elems,
+		std::function<void(void *)> func);
+
 template<typename Container, typename Func>
 void parallel(int jobs, Container &cont, Func func) {
-	// TODO: Actually run this in parallel
-	for (auto &elem: cont) {
-		func(elem);
+	if (jobs == 1) {
+		for (auto &elem: cont) {
+			func(elem);
+		}
+	} else {
+		std::vector<void *> elems;
+		for (auto &elem: cont) {
+			elems.push_back((void *)&elem);
+		}
+
+		runJobs(jobs, elems, [&func](void *el) {
+			func(*(typename Container::value_type *)el);
+		});
 	}
 }
 
-inline int coreCount() {
-	return std::thread::hardware_concurrency();
-}
+int coreCount();
 
 }