1 files changed, 120 insertions, 0 deletions
diff --git a/src/deps.cc b/src/deps.cc
new file mode 100644
index 0000000..9400b35
--- /dev/null
+++ b/src/deps.cc
@@ -0,0 +1,120 @@
+// -*- c++ -*-
+// Distributed under the BSD 2-Clause License.
+// See accompanying file LICENSE for details.
+#include "deps.h"
+
+#include "util.h"
+
+#include <fstream>
+
+namespace {
+/* Format example:
+build/src/libctor_a-libctor_cc.o: src/libctor.cc \
+ src/getoptpp/getoptpp.hpp src/ctor.h src/configure.h src/rebuild.h \
+ src/A\ B\ C.h src/task.h src/build.h src/unittest.h
+ */
+std::vector<std::string> readDepsMake(const std::string& dep_file)
+{
+	auto str = readFile(dep_file);
+
+	std::vector<std::string> output;
+	std::string tmp;
+
+	enum class State
+	{
+		pre_colon,
+		post_colon,
+		in_escape,
+	} state{State::pre_colon};
+
+	auto old_state{state};
+	for(const auto& c : str)
+	{
+		if(c == '\r')
+		{
+			// just always ignore windows extra newline char
+			continue;
+		}
+
+		switch(state)
+		{
+		case State::pre_colon:
+			if(c == ':') // ignore everything until the colon
+			{
+				state = State::post_colon;
+				continue;
+			}
+			continue;
+
+		case State::post_colon:
+			if(c == '\n')
+			{
+				// done
+				if(!tmp.empty())
+				{
+					output.emplace_back(tmp);
+				}
+				return output;
+			}
+			if(c == '\\')
+			{
+				old_state = state;
+				state = State::in_escape;
+				continue;
+			}
+			if(c == '\t' || c == ' ') // new token
+			{
+				if(!tmp.empty())
+				{
+					output.emplace_back(tmp);
+				}
+				tmp.clear();
+				continue;
+			}
+			break;
+
+		case State::in_escape:
+			if(c == '\n')
+			{
+				// linewrap
+				state = old_state;
+				continue;
+			}
+			state = old_state;
+			break;
+		}
+
+		tmp += c;
+	}
+
+	if(!tmp.empty())
+	{
+		output.emplace_back(tmp);
+	}
+
+	return output;
+}
+}
+
+std::vector<std::string> readDeps(const std::string& dep_file,
+                                  ctor::toolchain toolchain)
+{
+	if(!std::filesystem::exists(dep_file))
+	{
+		return {};
+	}
+
+	switch(toolchain)
+	{
+	case ctor::toolchain::any:
+	case ctor::toolchain::none:
+		return {};
+
+	// makefile .d file based:
+	case ctor::toolchain::gcc:
+	case ctor::toolchain::clang:
+		return readDepsMake(dep_file);
+	}
+
+	return {};
+}