From 6475e8951e1901b247f5d1d1dd9fcfc1e77e163a Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 27 Oct 2009 07:56:39 +0000
Subject: [PATCH] Check for and report OpenGL errors after each function call

---
 gl.files                  |  1 +
 source/functions.enum.t   |  1 +
 source/gldecoder.c        | 29 ++++++++++++++++++++++++++---
 source/gldecoder.funcs.t  |  2 +-
 source/gldecoder.struct.t |  1 +
 source/glprint.c          |  8 ++++++++
 source/glwrap.c           | 26 ++++++++++++++++++++++++++
 source/glwrap.funcs.t     |  2 ++
 8 files changed, 66 insertions(+), 4 deletions(-)

diff --git a/gl.files b/gl.files
index 8be2a33..d6631d8 100644
--- a/gl.files
+++ b/gl.files
@@ -4,3 +4,4 @@ spec gl.spec
 prefix gl
 ignore category VERSION_3_2
 ignore category ARB_sync
+ignore function glGetError
diff --git a/source/functions.enum.t b/source/functions.enum.t
index fc0987c..ad1bc2d 100644
--- a/source/functions.enum.t
+++ b/source/functions.enum.t
@@ -3,4 +3,5 @@
 :{
 :	FUNC_NONE,
 wl('	FUNC_%s,', func.name.upper())
+:	FUNC_GLDERROR = 0x8000
 :};
diff --git a/source/gldecoder.c b/source/gldecoder.c
index e11d13c..6e90373 100644
--- a/source/gldecoder.c
+++ b/source/gldecoder.c
@@ -12,7 +12,8 @@ Distributed under the GPL
 
 static unsigned read_short(short *, const char *);
 static unsigned read_int(int *, const char *);
-static int decode_func(GlDecoder *, short, const char *);
+static int decode_func(GlDecoder *, unsigned short, const char *);
+static int decode_gldfunc(GlDecoder *, unsigned short, const char *);
 
 GlDecoder *gldecoder_new(void *user_data, void (*destroy)(void *))
 {
@@ -37,7 +38,7 @@ int gldecoder_decode(GlDecoder *dec, const char *data, unsigned len)
 {
 	unsigned pos = 0;
 	int pktlen;
-	short func;
+	unsigned short func;
 	int ret;
 
 	if(len<sizeof(int)+sizeof(short))
@@ -48,7 +49,10 @@ int gldecoder_decode(GlDecoder *dec, const char *data, unsigned len)
 	pos += read_short(&func, data+pos);
 	if(dec)
 	{
-		ret = decode_func(dec, func, data+pos);
+		if(func&0x8000)
+			ret = decode_gldfunc(dec, func, data+pos);
+		else
+			ret = decode_func(dec, func, data+pos);
 		if(ret<0)
 			return -1;
 	}
@@ -127,3 +131,22 @@ static unsigned read_string(const unsigned char **v, const char *data)
 }
 
 #include "gldecoder.funcs"
+
+static int decode_gldError(GlDecoder *dec, const char *data)
+{
+	unsigned pos = 0;
+	GLenum code;
+	pos += read_int(&code, data);
+	if(dec->gldError)
+		dec->gldError(dec->user_data, code);
+	return pos;
+}
+
+static int decode_gldfunc(GlDecoder *dec, unsigned short func, const char *data)
+{
+	switch(func)
+	{
+	case FUNC_GLDERROR: return decode_gldError(dec, data);
+	default: return -1;
+	}
+}
diff --git a/source/gldecoder.funcs.t b/source/gldecoder.funcs.t
index 8d054b0..af820a4 100644
--- a/source/gldecoder.funcs.t
+++ b/source/gldecoder.funcs.t
@@ -24,7 +24,7 @@ for p in params:
 wl(');')
 wl('	return pos;')
 wl('}')
-:static int decode_func(GlDecoder *dec, short func, const char *data)
+:static int decode_func(GlDecoder *dec, unsigned short func, const char *data)
 :{
 :	switch(func)
 :	{
diff --git a/source/gldecoder.struct.t b/source/gldecoder.struct.t
index e05e910..5b46aca 100644
--- a/source/gldecoder.struct.t
+++ b/source/gldecoder.struct.t
@@ -9,4 +9,5 @@ if ret.ctype!="void":
 for p in params:
 	w(', %s', p.ctype)
 wl(');')
+:	void (*gldError)(void *, GLenum);
 :} GlDecoder;
diff --git a/source/glprint.c b/source/glprint.c
index 3c07559..fbf6e0e 100644
--- a/source/glprint.c
+++ b/source/glprint.c
@@ -18,6 +18,7 @@ typedef struct sGlPrintData
 
 static void init_print(GlDecoder *);
 static void glprint_data_free(void *);
+static void print_gldError(void *, GLenum);
 
 GlDecoder *glprint_new(char *buffer, unsigned bufsize)
 {
@@ -38,6 +39,7 @@ GlDecoder *glprint_new(char *buffer, unsigned bufsize)
 		dec = gldecoder_new(gpd, free);
 
 	init_print(dec);
+	dec->gldError = print_gldError;
 }
 
 char *glprint_get_buffer(GlDecoder *dec)
@@ -52,4 +54,10 @@ static void glprint_data_free(void *data)
 	free(gpd);
 }
 
+static void print_gldError(void *user_data, GLenum code)
+{
+	GlPrintData *gpd = (GlPrintData *)user_data;
+	snprintf(gpd->buffer, gpd->bufsize, "ERROR: %s", describe_enum(code, "ErrorCode"));
+}
+
 #include "glprint.funcs"
diff --git a/source/glwrap.c b/source/glwrap.c
index 224a0fa..0a22c3c 100644
--- a/source/glwrap.c
+++ b/source/glwrap.c
@@ -239,6 +239,32 @@ static inline int mapsize(GLenum target)
 	return 1;
 }
 
+GLenum cur_error = GL_NO_ERROR;
+
+static void check_error()
+{
+	GLenum (*orig_glGetError)() = 0;
+	GLenum code;
+	if(!orig_glGetError)
+		orig_glGetError = glsym("glGetError");
+	code = orig_glGetError();
+	if(code!=GL_NO_ERROR)
+	{
+		begin_packet(FUNC_GLDERROR);
+		write_int(code);
+		send_packet();
+		if(cur_error==GL_NO_ERROR)
+			cur_error = code;
+	}
+}
+
+GLenum APIENTRY glGetError()
+{
+	GLenum ret = cur_error;
+	cur_error = GL_NO_ERROR;
+	return ret;
+}
+
 void (*glXGetProcAddress(const GLubyte *procname))(void)
 {
 	void *handle = dlopen(NULL, RTLD_LAZY);
diff --git a/source/glwrap.funcs.t b/source/glwrap.funcs.t
index decf22e..a58a1c5 100644
--- a/source/glwrap.funcs.t
+++ b/source/glwrap.funcs.t
@@ -21,6 +21,8 @@ for p in params:
 	else:
 		wl('	write_pointer(%s);', p.name)
 wl('	send_packet();')
+if not func.name.startswith("glX"):
+	wl('	check_error();')
 if ret.ctype!='void':
 	wl('	return ret;')
 wl('}')
-- 
2.45.2