translates windows drive letters to canonical paths

CMakeLists.txt

@@ -46,7 +46,7 @@ include_directories("${CMAKE_CURRENT_BINARY_DIR}/include")
 set(src "${CMAKE_SOURCE_DIR}/src")
 
 lava_create_gutlib(
-        SUBDIRS bottles config launch
+        SUBDIRS bottles config launch paths
         DEPENDS cog)
 
 lava_create_executable(TARGET cellar

include/paths.hpp

@@ -5,5 +5,6 @@
 namespace cellar {
     namespace paths {
         extern std::string translate(std::string in_path, bool lazy = false);
+        extern std::string resolve_drive_letter(std::string in_path);
     }
 }

src/paths/drive_letters.cpp

@@ -0,0 +1,51 @@
+#include <exception>
+#include <regex>
+#include <string>
+#include <unistd.h>
+
+#include <boost/algorithm/string.hpp>
+
+#include "bottles.hpp"
+#include "output.hpp"
+#include "paths.hpp"
+
+using namespace std;
+
+string cellar::paths::resolve_drive_letter(string in_path) {
+    bool windows_input;
+    static regex drive_letter_rgx(R"([a-zA-Z]:\\)");
+
+    windows_input = regex_match(in_path.substr(0, 3), drive_letter_rgx);
+
+    string out_path = "";
+
+    if (windows_input) {
+        string drive_letter = boost::algorithm::to_lower_copy(in_path.substr(0, 2));
+
+        string link_path = "";
+        link_path.append(bottles::active_bottle.canonical_path);
+        link_path.append("/dosdevices/");
+        link_path.append(drive_letter);
+        
+        char stringbuffer[512];
+        ssize_t bufflen = readlink(link_path.c_str(), stringbuffer, sizeof(stringbuffer) - 1);
+
+        if (bufflen != -1) {
+            stringbuffer[bufflen] = '\0';
+            out_path.append(stringbuffer);
+        } else {
+            throw runtime_error("readlink isn't having it");
+        }
+
+        string rest_of_path = in_path.substr(3, in_path.size() - 2);
+        size_t slashpos = rest_of_path.find("\\");
+        while (slashpos != std::string::npos) {
+            rest_of_path.replace(0, 1, "/");
+            slashpos = rest_of_path.find("\\");
+        }
+
+        out_path.append(rest_of_path);
+    }
+
+    return out_path;
+}