From 17a51b0b31c6e7f0d862fe30d3a3222d152c2966 Mon Sep 17 00:00:00 2001
From: Karol Herbst <kherbst@redhat.com>
Date: Wed, 5 May 2021 14:01:57 +0200
Subject: [PATCH] nouveau: rework debugging so we can also dump into a file

Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
---
 nouveau/nouveau.c | 26 ++++++++++++++++++++++----
 nouveau/private.h |  7 +++++--
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/nouveau/nouveau.c b/nouveau/nouveau.c
index 80c62c58..9fa940a9 100644
--- a/nouveau/nouveau.c
+++ b/nouveau/nouveau.c
@@ -46,15 +46,33 @@
 #include "nvif/ioctl.h"
 #include "nvif/unpack.h"
 
+drm_private FILE *nouveau_out = NULL;
 drm_private uint32_t nouveau_debug = 0;
 
 static void
-debug_init(char *args)
+debug_init(void)
 {
-	if (args) {
-		int n = strtol(args, NULL, 0);
+	static bool once = false;
+	char *debug, *out;
+
+	if (once)
+		return;
+	once = true;
+
+	debug = getenv("NOUVEAU_LIBDRM_DEBUG");
+	if (debug) {
+		int n = strtol(debug, NULL, 0);
 		if (n >= 0)
 			nouveau_debug = n;
+
+	}
+
+	nouveau_out = stderr;
+	out = getenv("NOUVEAU_LIBDRM_OUT");
+	if (out) {
+		FILE *fout = fopen(out, "w");
+		if (fout)
+			nouveau_out = fout;
 	}
 }
 
@@ -325,7 +343,7 @@ nouveau_drm_new(int fd, struct nouveau_drm **pdrm)
 	struct nouveau_drm *drm;
 	drmVersionPtr ver;
 
-	debug_init(getenv("NOUVEAU_LIBDRM_DEBUG"));
+	debug_init();
 
 	if (!(drm = calloc(1, sizeof(*drm))))
 		return -ENOMEM;
diff --git a/nouveau/private.h b/nouveau/private.h
index 13cec3cd..55fe57d8 100644
--- a/nouveau/private.h
+++ b/nouveau/private.h
@@ -1,6 +1,8 @@
 #ifndef __NOUVEAU_LIBDRM_PRIVATE_H__
 #define __NOUVEAU_LIBDRM_PRIVATE_H__
 
+#include <stdio.h>
+
 #include <libdrm_macros.h>
 #include <xf86drm.h>
 #include <xf86atomic.h>
@@ -10,12 +12,13 @@
 #include "nouveau.h"
 
 drm_private extern uint32_t nouveau_debug;
+drm_private extern FILE *nouveau_out;
 #define dbg_on(lvl) (nouveau_debug & (1 << lvl))
 #define dbg(lvl, fmt, args...) do {                                            \
 	if (dbg_on((lvl)))                                                     \
-		fprintf(stderr, "nouveau: "fmt, ##args);                       \
+		fprintf(nouveau_out, "nouveau: "fmt, ##args);                       \
 } while(0)
-#define err(fmt, args...) fprintf(stderr, "nouveau: "fmt, ##args)
+#define err(fmt, args...) fprintf(nouveau_out, "nouveau: "fmt, ##args)
 
 struct nouveau_client_kref {
 	struct drm_nouveau_gem_pushbuf_bo *kref;