Use Win32 Unicode APIs and expect all strings to be UTF-8 (fixes OSGe…

…o#1765)

For backward compatibility, if PROJ_LIB content is found to be not UTF-8 or
pointing to a non existing directory, then an attempt at interpretating it
in the ANSI page encoding is done.

proj_context_set_search_paths() now assumes strings to be in UTF-8, and
functions returning paths will also return values in UTF-8.

src/4D_api.cpp

@@ -1461,10 +1461,10 @@ PJ_INFO proj_info (void) {
                             pj_context_get_user_writable_directory(ctx, false).c_str(),
                             &buf_size);
         }
-        const char *envPROJ_LIB = getenv("PROJ_LIB");
-        buf = path_append(buf, envPROJ_LIB, &buf_size);
+        const std::string envPROJ_LIB = NS_PROJ::FileManager::getProjLibEnvVar(ctx);
+        buf = path_append(buf, envPROJ_LIB.empty() ? nullptr : envPROJ_LIB.c_str(), &buf_size);
 #ifdef PROJ_LIB
-        if (envPROJ_LIB == nullptr) {
+        if (envPROJ_LIB.empty()) {
             buf = path_append(buf, PROJ_LIB, &buf_size);
         }
 #endif
@@ -1770,3 +1770,4 @@ PJ_FACTORS proj_factors(PJ *P, PJ_COORD lp) {
 
     return factors;
 }
+

src/Makefile.am

@@ -190,7 +190,7 @@ libproj_la_SOURCES = \
 	deriv.cpp ell_set.cpp ellps.cpp errno.cpp \
 	factors.cpp fwd.cpp init.cpp inv.cpp \
 	list.cpp malloc.cpp mlfn.cpp msfn.cpp proj_mdist.cpp \
-	open_lib.cpp param.cpp phi2.cpp pr_list.cpp \
+	param.cpp phi2.cpp pr_list.cpp \
 	qsfn.cpp strerrno.cpp \
 	tsfn.cpp units.cpp ctx.cpp log.cpp zpoly1.cpp rtodms.cpp \
 	release.cpp gauss.cpp \