Make all client API functions dynamically loaded

README.md

@@ -64,6 +64,7 @@ GLFW bundles a number of dependencies in the `deps/` directory.
 
 ## Changelog
 
+ - Made all client API functions dynamically loaded
  - Changed minimum required CMake version to 2.8.12
  - Replaced GLU with [linmath.h](https://github.com/datenwolf/linmath.h) in
    example programs

src/context.c

@@ -38,6 +38,7 @@
 static GLboolean parseVersionString(int* api, int* major, int* minor, int* rev)
 {
     int i;
+    _GLFWwindow* window;
     const char* version;
     const char* prefixes[] =
     {
@@ -49,7 +50,9 @@ static GLboolean parseVersionString(int* api, int* major, int* minor, int* rev)
 
     *api = GLFW_OPENGL_API;
 
-    version = (const char*) glGetString(GL_VERSION);
+    window = _glfwPlatformGetCurrentContext();
+
+    version = (const char*) window->GetString(GL_VERSION);
     if (!version)
     {
         _glfwInputError(GLFW_PLATFORM_ERROR,
@@ -352,6 +355,10 @@ GLboolean _glfwRefreshContextAttribs(const _GLFWctxconfig* ctxconfig)
 {
     _GLFWwindow* window = _glfwPlatformGetCurrentContext();
 
+    window->GetIntegerv = (PFNGLGETINTEGERVPROC) glfwGetProcAddress("glGetIntegerv");
+    window->GetString = (PFNGLGETSTRINGPROC) glfwGetProcAddress("glGetString");
+    window->Clear = (PFNGLCLEARPROC) glfwGetProcAddress("glClear");
+
     if (!parseVersionString(&window->context.api,
                             &window->context.major,
                             &window->context.minor,
@@ -382,7 +389,7 @@ GLboolean _glfwRefreshContextAttribs(const _GLFWctxconfig* ctxconfig)
         if (window->context.major >= 3)
         {
             GLint flags;
-            glGetIntegerv(GL_CONTEXT_FLAGS, &flags);
+            window->GetIntegerv(GL_CONTEXT_FLAGS, &flags);
 
             if (flags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT)
                 window->context.forward = GL_TRUE;
@@ -404,7 +411,7 @@ GLboolean _glfwRefreshContextAttribs(const _GLFWctxconfig* ctxconfig)
             (window->context.major == 3 && window->context.minor >= 2))
         {
             GLint mask;
-            glGetIntegerv(GL_CONTEXT_PROFILE_MASK, &mask);
+            window->GetIntegerv(GL_CONTEXT_PROFILE_MASK, &mask);
 
             if (mask & GL_CONTEXT_COMPATIBILITY_PROFILE_BIT)
                 window->context.profile = GLFW_OPENGL_COMPAT_PROFILE;
@@ -427,7 +434,7 @@ GLboolean _glfwRefreshContextAttribs(const _GLFWctxconfig* ctxconfig)
             //       only present from 3.0 while the extension applies from 1.1
 
             GLint strategy;
-            glGetIntegerv(GL_RESET_NOTIFICATION_STRATEGY_ARB, &strategy);
+            window->GetIntegerv(GL_RESET_NOTIFICATION_STRATEGY_ARB, &strategy);
 
             if (strategy == GL_LOSE_CONTEXT_ON_RESET_ARB)
                 window->context.robustness = GLFW_LOSE_CONTEXT_ON_RESET;
@@ -444,7 +451,7 @@ GLboolean _glfwRefreshContextAttribs(const _GLFWctxconfig* ctxconfig)
             //       one, so we can reuse them here
 
             GLint strategy;
-            glGetIntegerv(GL_RESET_NOTIFICATION_STRATEGY_ARB, &strategy);
+            window->GetIntegerv(GL_RESET_NOTIFICATION_STRATEGY_ARB, &strategy);
 
             if (strategy == GL_LOSE_CONTEXT_ON_RESET_ARB)
                 window->context.robustness = GLFW_LOSE_CONTEXT_ON_RESET;
@@ -456,7 +463,7 @@ GLboolean _glfwRefreshContextAttribs(const _GLFWctxconfig* ctxconfig)
     if (glfwExtensionSupported("GL_KHR_context_flush_control"))
     {
         GLint behavior;
-        glGetIntegerv(GL_CONTEXT_RELEASE_BEHAVIOR, &behavior);
+        window->GetIntegerv(GL_CONTEXT_RELEASE_BEHAVIOR, &behavior);
 
         if (behavior == GL_NONE)
             window->context.release = GLFW_RELEASE_BEHAVIOR_NONE;
@@ -581,7 +588,7 @@ GLFWAPI int glfwExtensionSupported(const char* extension)
 
         // Check if extension is in the modern OpenGL extensions string list
 
-        glGetIntegerv(GL_NUM_EXTENSIONS, &count);
+        window->GetIntegerv(GL_NUM_EXTENSIONS, &count);
 
         for (i = 0;  i < count;  i++)
         {
@@ -602,7 +609,7 @@ GLFWAPI int glfwExtensionSupported(const char* extension)
     {
         // Check if extension is in the old style OpenGL extensions string
 
-        const char* extensions = (const char*) glGetString(GL_EXTENSIONS);
+        const char* extensions = (const char*) window->GetString(GL_EXTENSIONS);
         if (!extensions)
         {
             _glfwInputError(GLFW_PLATFORM_ERROR,

src/internal.h

@@ -69,6 +69,10 @@
  #include "../deps/GL/glext.h"
 #endif
 
+typedef void (APIENTRY * PFNGLCLEARPROC)(GLbitfield);
+typedef const GLubyte* (APIENTRY * PFNGLGETSTRINGPROC)(GLenum);
+typedef void (APIENTRY * PFNGLGETINTEGERVPROC)(GLenum,GLint*);
+
 typedef struct _GLFWwndconfig   _GLFWwndconfig;
 typedef struct _GLFWctxconfig   _GLFWctxconfig;
 typedef struct _GLFWfbconfig    _GLFWfbconfig;
@@ -261,6 +265,9 @@ struct _GLFWwindow
 #if defined(_GLFW_USE_OPENGL)
     PFNGLGETSTRINGIPROC GetStringi;
 #endif
+    PFNGLGETINTEGERVPROC GetIntegerv;
+    PFNGLGETSTRINGPROC  GetString;
+    PFNGLCLEARPROC      Clear;
 
     struct {
         GLFWwindowposfun        pos;

src/window.c

@@ -202,7 +202,7 @@ GLFWAPI GLFWwindow* glfwCreateWindow(int width, int height,
 
     // Clearing the front buffer to black to avoid garbage pixels left over
     // from previous uses of our bit of VRAM
-    glClear(GL_COLOR_BUFFER_BIT);
+    window->Clear(GL_COLOR_BUFFER_BIT);
     _glfwPlatformSwapBuffers(window);
 
     // Restore the previously current context (or NULL)