Fixed X11 character input for C locale.

Fixes #396.

README.md

@@ -144,6 +144,7 @@ GLFW bundles a number of dependencies in the `deps/` directory.
  - [X11] Bugfix: X-axis scroll offsets were inverted
  - [X11] Bugfix: Full screen override redirect windows were not always
                  positioned over the specified monitor
+ - [X11] Bugfix: Character input did not work for the default `"C"` locale
 
 
 ## Contact

include/GLFW/glfw3.h

@@ -1089,6 +1089,12 @@ typedef struct GLFWimage
  *  bundle, if present.  This can be disabled with a
  *  [compile-time option](@ref compile_options_osx).
  *
+ *  @remarks __X11:__ If the `LC_CTYPE` category of the current locale is set to
+ *  `"C"` then the environment's locale will be applied to that category.  This
+ *  is done because character input will not function when `LC_CTYPE` is set to
+ *  `"C"`.  If another locale was set before this function was called, it will
+ *  be left untouched.
+ *
  *  @par Thread Safety
  *  This function may only be called from the main thread.
  *

src/x11_init.c

@@ -33,6 +33,7 @@
 #include <string.h>
 #include <limits.h>
 #include <stdio.h>
+#include <locale.h>
 
 
 // Translate an X11 key code to a GLFW key code.
@@ -709,6 +710,9 @@ Cursor _glfwCreateCursor(const GLFWimage* image, int xhot, int yhot)
 
 int _glfwPlatformInit(void)
 {
+    if (strcmp(setlocale(LC_CTYPE, NULL), "C") == 0)
+        setlocale(LC_CTYPE, "");
+
     XInitThreads();
 
     _glfw.x11.display = XOpenDisplay(NULL);

tests/events.c

@@ -37,7 +37,6 @@
 #include <stdlib.h>
 #include <ctype.h>
 #include <string.h>
-#include <locale.h>
 
 #include "getopt.h"
 
@@ -443,8 +442,6 @@ int main(int argc, char** argv)
     GLFWmonitor* monitor = NULL;
     int ch, i, width, height, count = 1;
 
-    setlocale(LC_ALL, "");
-
     glfwSetErrorCallback(error_callback);
 
     if (!glfwInit())