lib/hexdump: Refactor to skip lines with all ones as well

We already do this for lines with all zeroes, so it makes sense to
treat all ones the same, for symmetry.

Change-Id: I4b637b07a49e0c649331aa200995b474dd9a2682
Signed-off-by: Alexandru Gagniuc <alexandrux.gagniuc@intel.com>
Reviewed-on: https://review.coreboot.org/12872
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

1 files changed, 25 insertions, 20 deletions

diff --git a/src/lib/hexdump.c b/src/lib/hexdump.c
index 7907a381b5..2861d6321e 100644
--- a/src/lib/hexdump.c
+++ b/src/lib/hexdump.c
@@ -23,39 +23,44 @@ static int isprint(int c)
 void hexdump(const void *memory, size_t length)
 {
 	int i;
-	uint8_t *m;
+	uint8_t *line;
 	int all_zero = 0;
-
-	m = (uint8_t *) memory;
+	int all_one = 0;
+	size_t num_bytes;
 
 	for (i = 0; i < length; i += 16) {
 		int j;
-		int left = MIN(length - i, 16);
+		num_bytes = MIN(length - i, 16);
+		line = ((uint8_t *)memory) + i;
+
+		all_zero++;
+		all_one++;
+		for (j = 0; j < num_bytes; j++) {
+			if (line[j] != 0) {
+				all_zero = 0;
+				break;
+			}
+		}
 
-		if (left < 16) {
-			all_zero = 0;
-		} else {
-			all_zero++;
-			for (j = 0; j < 16; j++) {
-				if (m[i + j] != 0) {
-					all_zero = 0;
-					break;
-				}
+		for (j = 0; j < num_bytes; j++) {
+			if (line[j] != 0xff) {
+				all_one = 0;
+				break;
 			}
 		}
 
-		if (all_zero < 2) {
+		if ((all_zero < 2) && (all_one < 2)) {
 			printk(BIOS_DEBUG, "%p:", memory + i);
-			for (j = 0; j < left; j++)
-				printk(BIOS_DEBUG, " %02x", m[i + j]);
-			for (j = left; j < 16; j++)
+			for (j = 0; j < num_bytes; j++)
+				printk(BIOS_DEBUG, " %02x", line[j]);
+			for (; j < 16; j++)
 				printk(BIOS_DEBUG, "   ");
 			printk(BIOS_DEBUG, "  ");
-			for (j = 0; j < left; j++)
+			for (j = 0; j < num_bytes; j++)
 				printk(BIOS_DEBUG, "%c",
-				       isprint(m[i + j]) ? m[i + j] : '.');
+				       isprint(line[j]) ? line[j] : '.');
 			printk(BIOS_DEBUG, "\n");
-		} else if (all_zero == 2) {
+		} else if ((all_zero == 2) || (all_one == 2)) {
 			printk(BIOS_DEBUG, "...\n");
 		}
 	}