Use C.UTF-8 instead of C if available

Mostly everything around us is UTF-8 these days, we need to get on with
the times. Especially now that glibc >= 2.35 finally supports it too.
Attempt to detect C.UTF-8 availability in cmake and prefer when available,
fall back to C when not.

Fixes: #2587

Author: pmatilai

CMakeLists.txt

@@ -130,6 +130,19 @@ function(makemacros)
 	findutil(__CPP cpp)
 	findutil(__CXX c++)
 
+	# Try to determine if C.UTF-8 is available
+	execute_process(COMMAND locale -a
+			OUTPUT_STRIP_TRAILING_WHITESPACE
+			OUTPUT_VARIABLE locale_a)
+	separate_arguments(locales UNIX_COMMAND ${locale_a})
+	list(FIND locales C.utf8 have_c_utf8)
+	if (have_c_utf8 GREATER_EQUAL 1)
+		set(C_LOCALE "C.UTF-8")
+	else()
+		set(C_LOCALE "C")
+	endif()
+	message(DEBUG " C locale ${C_LOCALE}")
+
 	list(GET db_backends 0 DB_BACKEND)
 
 	set(host_cpu ${CMAKE_HOST_SYSTEM_PROCESSOR})

build/files.c

@@ -2415,7 +2415,7 @@ static void processSpecialDir(rpmSpec spec, Package pkg, FileList fl,
     appendStringBuf(docScript, sdenv);
     appendStringBuf(docScript, "=$RPM_BUILD_ROOT");
     appendLineStringBuf(docScript, sd->dirname);
-    appendLineStringBuf(docScript, "export LC_ALL=C");
+    appendLineStringBuf(docScript, "export LC_ALL=" C_LOCALE);
     appendStringBuf(docScript, "export ");
     appendLineStringBuf(docScript, sdenv);
     appendLineStringBuf(docScript, mkdocdir);

config.h.in

@@ -114,6 +114,7 @@
 
 #define UID_0_USER "@UID_0_USER@"
 #define GID_0_GROUP "@GID_0_GROUP@"
+#define C_LOCALE "@C_LOCALE@"
 
 #define PACKAGE "@PROJECT_NAME@"
 #define VERSION "@PROJECT_VERSION@"

macros.in

@@ -772,7 +772,7 @@ Supplements:   (%{name} = %{version}-%{release} and langpacks-%{1})\
   RPM_PACKAGE_VERSION=\"%{VERSION}\"\
   RPM_PACKAGE_RELEASE=\"%{RELEASE}\"\
   export RPM_PACKAGE_NAME RPM_PACKAGE_VERSION RPM_PACKAGE_RELEASE\
-  LANG=C\
+  LANG=@C_LOCALE@\
   export LANG\
   unset CDPATH DISPLAY ||:\
   unset DEBUGINFOD_URLS ||:\

rpmio/rpmglob.c

@@ -96,8 +96,8 @@ int rpmGlobPath(const char * pattern, rpmglobFlags flags,
     t = setlocale(LC_CTYPE, NULL);
     if (t)
     	old_ctype = xstrdup(t);
-    (void) setlocale(LC_COLLATE, "C");
-    (void) setlocale(LC_CTYPE, "C");
+    (void) setlocale(LC_COLLATE, C_LOCALE);
+    (void) setlocale(LC_CTYPE, C_LOCALE);
 #endif
 
     gl.gl_pathc = 0;