Add testpatchentrypoints unit test

This unit test verifies that entrypoint patching works as expected, by
loading libGLX_patchentry.so, looking up the address of
__glXSawVertex3fv defined in libGLX_patchentry.so, and verifying that
the value at this symbol matches the number of calls to glVertex3fv()
(which is hacked to increment __glXSawVertex3fv via entrypoint
rewriting).

3 files changed, 118 insertions, 0 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 190a1a9..63dc369 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -48,6 +48,7 @@ TESTS = \
 	testglxqueryversion.sh \
 	testglxnscreens.sh \
 	testglxnscrthreads.sh \
+	testpatchentrypoints.sh \
 	fini_test_env.sh
 
 EXTRA_DIST = $(TESTS)
@@ -59,6 +60,7 @@ check_PROGRAMS = \
 	testx11glvndproto \
 	testglxgetclientstr \
 	testglxqueryversion \
+	testpatchentrypoints \
 	testglxnscreens
 
 testglxnscreens_SOURCES = \
@@ -123,3 +125,12 @@ testglxqueryversion_LDADD = -lX11
 testglxqueryversion_LDADD += $(top_builddir)/src/GLX/libGLX.la
 testglxqueryversion_LDADD += $(top_builddir)/src/OpenGL/libOpenGL.la
 testglxqueryversion_LDADD += $(top_builddir)/src/util/trace/libtrace.la
+
+testpatchentrypoints_SOURCES = \
+	testpatchentrypoints.c \
+	test_utils.c
+
+testpatchentrypoints_LDADD = -lX11 -ldl
+testpatchentrypoints_LDADD += $(top_builddir)/src/GLX/libGLX.la
+testpatchentrypoints_LDADD += $(top_builddir)/src/OpenGL/libOpenGL.la
+testpatchentrypoints_LDADD += $(top_builddir)/src/util/trace/libtrace.la
diff --git a/tests/testpatchentrypoints.c b/tests/testpatchentrypoints.c
new file mode 100644
index 0000000..59ba045
--- /dev/null
+++ b/tests/testpatchentrypoints.c
@@ -0,0 +1,100 @@
+#define _GNU_SOURCE 1
+
+#include <string.h>
+#include <X11/X.h>
+#include <GL/gl.h>
+#include <dlfcn.h>
+#include "test_utils.h"
+
+#define NUM_VERTEX3FV_CALLS 100
+
+int main(int argc, char **argv)
+{
+    struct window_info wi;
+    Display *dpy = XOpenDisplay(NULL);
+    int sawVertex3fv1, sawVertex3fv2, *pSawVertex3fv;
+    int i;
+    int ret = 1;
+    GLXContext ctx = None;
+    void *vendorHandle;
+
+    if (!dpy) {
+        printError("No display!\n");
+        goto fail;
+    }
+
+    memset(&wi, 0, sizeof(wi));
+
+    if (!testUtilsCreateWindow(dpy, &wi, 0)) {
+        printError("Failed to create window!\n");
+        goto fail;
+    }
+
+    ctx = glXCreateContext(dpy, wi.visinfo, NULL, GL_TRUE);
+    if (!ctx) {
+        printError("Failed to create a context!\n");
+        goto fail;
+    }
+
+    if (!glXMakeContextCurrent(dpy, wi.win, wi.win, ctx)) {
+        printError("Failed to make current\n");
+        goto fail;
+    }
+
+    vendorHandle = dlopen("libGLX_patchentry.so", RTLD_LAZY);
+    if (!vendorHandle) {
+        printError("No valid vendor library handle\n");
+        goto fail;
+    }
+
+    pSawVertex3fv = (int *)dlsym(vendorHandle, "__glXSawVertex3fv");
+    if (!pSawVertex3fv) {
+        printError("Could not find __glXSawVertex3fv\n");
+        goto fail;
+    }
+
+    for (i = 0; i < NUM_VERTEX3FV_CALLS; i++) {
+        glVertex3fv(NULL);
+    }
+
+    // Read the resulting value
+    sawVertex3fv1 = *pSawVertex3fv;
+
+    if (!glXMakeContextCurrent(dpy, None, None, NULL)) {
+        printError("Could not lose current\n");
+        goto fail;
+    }
+
+    // Read again. The NOP stubs should be restored by libglvnd
+    for (i = 0; i < NUM_VERTEX3FV_CALLS; i++) {
+        glVertex3fv(NULL);
+    }
+
+    sawVertex3fv2 = *pSawVertex3fv;
+
+    dlclose(vendorHandle);
+    pSawVertex3fv = NULL;
+
+    if (sawVertex3fv1 != NUM_VERTEX3FV_CALLS) {
+        printError("sawVertex3fv1 mismatch: expected %d, got %d\n",
+                   NUM_VERTEX3FV_CALLS, sawVertex3fv1);
+        goto fail;
+    }
+
+    if (sawVertex3fv2 != sawVertex3fv1) {
+        printError("sawVertex3fv2 mismatch: expected %d, got %d\n",
+                   NUM_VERTEX3FV_CALLS, sawVertex3fv2);
+        goto fail;
+    }
+
+    ret = 0;
+
+fail:
+    if (ctx) {
+        glXDestroyContext(dpy, ctx);
+    }
+
+    testUtilsDestroyWindow(dpy, &wi);
+
+    return ret;
+}
diff --git a/tests/testpatchentrypoints.sh b/tests/testpatchentrypoints.sh
new file mode 100755
index 0000000..fcd2b81
--- /dev/null
+++ b/tests/testpatchentrypoints.sh
@@ -0,0 +1,7 @@
+#!/bin/bash
+
+export __GLX_VENDOR_LIBRARY_NAME=patchentry
+export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$TOP_BUILDDIR/tests/GLX_dummy/.libs
+
+# Run the patch entrypoint test.
+./testpatchentrypoints