[Intel-gfx] [PATCH igt] tools/error_decode: Print ASCII user buffers

[Chris Wilson]

Look at the first 16 characters of the user buffer and if they are all
printable, assume that user buffer contains ASCII data (e.g. a debug log)
that we want to simply print out. Otherwise, we treat it as a binary data
and hexdump as before.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 tools/intel_error_decode.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/tools/intel_error_decode.c b/tools/intel_error_decode.c
index cdef3b18..84ef72b6 100644
--- a/tools/intel_error_decode.c
+++ b/tools/intel_error_decode.c
@@ -51,6 +51,7 @@
 #include <assert.h>
 #include <intel_bufmgr.h>
 #include <zlib.h>
+#include <ctype.h>
 
 #include "intel_chipset.h"
 #include "intel_io.h"
@@ -434,6 +435,16 @@ print_fault_data(unsigned devid, uint32_t data1, uint32_t data0)
 
 #define MAX_RINGS 10 /* I really hope this never... */
 
+static bool maybe_ascii(const void *data, int check)
+{
+	const char *c = data;
+	while (check--) {
+		if (!isprint(*c++))
+			return false;
+	}
+	return true;
+}
+
 static void decode(struct drm_intel_decode *ctx,
 		   const char *buffer_name,
 		   const char *ring_name,
@@ -458,6 +469,15 @@ static void decode(struct drm_intel_decode *ctx,
 		drm_intel_decode_set_batch_pointer(ctx, data, gtt_offset,
 						   *count);
 		drm_intel_decode(ctx);
+	} else if (maybe_ascii(data, 16)) {
+		char *c = (char *)data;
+		int max = 4 * *count;
+		for (int i = 0; i < max; i++) {
+			if (!c[i])
+				break;
+			putchar(c[i]);
+		}
+		putchar('\n');
 	} else {
 		for (int i = 0; i + 4 <= *count; i += 4)
 			printf("[%04x] %08x %08x %08x %08x\n",
-- 
2.15.0