emulator/opengl: A few debugging, stability improvements to emugl

* Zero output parameters so that errors don't return random
  data (even if the target code was careful to zero its output
  parameters.)  Spec says that we will not modify values in case of
  an error, which is not currently possible, but at least this
  means we return deterministic values.

* Similarly, avoid passing uninitialized data if an error occurs
  during getting the viewport.

* Fix a bug where glGetError may be called when NULL is decoded in
  CHECK_GL_ERROR mode.

* Output more information about the stream in DEBUG_PRINTOUT mode to
  help separate from multiple streams.

Change-Id: I31706b92642efe4c7ed38d178b49e72835a9c9a6

3 files changed, 8 insertions, 4 deletions

diff --git a/emulator/opengl/host/libs/Translator/GLES_CM/GLEScmImp.cpp b/emulator/opengl/host/libs/Translator/GLES_CM/GLEScmImp.cpp
index 3443f59..dd74750 100644
--- a/emulator/opengl/host/libs/Translator/GLES_CM/GLEScmImp.cpp
+++ b/emulator/opengl/host/libs/Translator/GLES_CM/GLEScmImp.cpp
@@ -2227,7 +2227,7 @@ void glDrawTexOES (T x, T y, T z, T width, T height) {
 
     int numClipPlanes;
 
-    GLint viewport[4];
+    GLint viewport[4] = {};
     z = (z>1 ? 1 : (z<0 ?  0 : z));
 
     T vertices[4*3] = {
diff --git a/emulator/opengl/host/libs/libOpenglRender/ColorBuffer.cpp b/emulator/opengl/host/libs/libOpenglRender/ColorBuffer.cpp
index f4280e1..532ffe7 100644
--- a/emulator/opengl/host/libs/libOpenglRender/ColorBuffer.cpp
+++ b/emulator/opengl/host/libs/libOpenglRender/ColorBuffer.cpp
@@ -204,7 +204,7 @@ bool ColorBuffer::blitFromCurrentReadBuffer()
             // save current viewport and match it to the current
             // colorbuffer size
             //
-            GLint vport[4];
+            GLint vport[4] = {};
             s_gl.glGetIntegerv(GL_VIEWPORT, vport);
             s_gl.glViewport(0, 0, m_width, m_height);
 
diff --git a/emulator/opengl/host/tools/emugen/ApiGen.cpp b/emulator/opengl/host/tools/emugen/ApiGen.cpp
index 6d6742d..2e4c8d1 100644
--- a/emulator/opengl/host/tools/emugen/ApiGen.cpp
+++ b/emulator/opengl/host/tools/emugen/ApiGen.cpp
@@ -821,7 +821,8 @@ int ApiGen::genDecoderImpl(const std::string &filename)
                 }
             } else if (pass == PASS_DebugPrint) {
                 fprintf(fp, "#ifdef DEBUG_PRINTOUT\n");
-                fprintf(fp, "\t\t\tfprintf(stderr,\"%s: %s(%s)\\n\"", m_basename.c_str(), e->name().c_str(), printString.c_str());
+                fprintf(fp, "\t\t\tfprintf(stderr,\"%s(%%p): %s(%s)\\n\", stream",
+                        m_basename.c_str(), e->name().c_str(), printString.c_str());
                 if (e->vars().size() > 0 && !e->vars()[0].isVoid()) fprintf(fp, ",");
             }
 
@@ -878,6 +879,9 @@ int ApiGen::genDecoderImpl(const std::string &filename)
                             } else if (pass == PASS_MemAlloc) {
                                 fprintf(fp, "\t\t\tunsigned char *tmpPtr%u = &tmpBuf[%s];\n",
                                         (unsigned)j, tmpBufOffset[j].c_str());
+                                fprintf(fp, "\t\t\tmemset(tmpPtr%u, 0, %s);\n",
+                                        (unsigned)j,
+                                        toString(v->type()->bytes()).c_str());
                             } else if (pass == PASS_FunctionCall) {
                                 if (v->nullAllowed()) {
                                     fprintf(fp, "tmpPtr%uSize == 0 ? NULL : (%s)(tmpPtr%u)",
@@ -937,7 +941,7 @@ int ApiGen::genDecoderImpl(const std::string &filename)
     fprintf(fp, "\t\t} //switch\n");
     if (strstr(m_basename.c_str(), "gl")) {
         fprintf(fp, "#ifdef CHECK_GL_ERROR\n");
-        fprintf(fp, "\tint err = this->glGetError();\n");
+        fprintf(fp, "\tint err = lastCall[0] ? this->glGetError() : GL_NO_ERROR;\n");
         fprintf(fp, "\tif (err) fprintf(stderr, \"%s Error: 0x%%X in %%s\\n\", err, lastCall);\n", m_basename.c_str());
         fprintf(fp, "#endif\n");
     }