[PATCH] [MTD] MTD-Utils: fix handling of ioctl return value in nand-utils

[Frank Haverkamp]

Older kernel do not implement the MTDFILEMODE ioctl. In this case
nandwrite and nanddump should have used MEMGETOOBSEL in combination
with MEMSETOOBSEL. Unfortunately the return value of the unsucessfull
ioctl is not -ENOTTY, but -1 and errno contains ENOTTY. This change
fixes this issue. I have not tested all cornercases. Would be
good if someone could do more careful testing than I did, or maybe
reviewing is sufficient in this case.

Signed-off-by: Frank Haverkamp <haver at vnet.ibm.com>
---
 nanddump.c  |   16 ++++++++--------
 nandwrite.c |   14 +++++++-------
 2 files changed, 15 insertions(+), 15 deletions(-)

--- mtd-utils.git.orig/nandwrite.c
+++ mtd-utils.git/nandwrite.c
@@ -271,9 +271,12 @@ int main(int argc, char **argv)
 	}
 
 	if (noecc)  {
-		switch (ioctl(fd, MTDFILEMODE, (void *) MTD_MODE_RAW)) {
-
-			case -ENOTTY:
+		ret = ioctl(fd, MTDFILEMODE, (void *) MTD_MODE_RAW);
+		if (ret == 0) {
+			oobinfochanged = 2;
+		} else {
+			switch (errno) {
+			case ENOTTY:
 				if (ioctl (fd, MEMGETOOBSEL, &old_oobinfo) != 0) {
 					perror ("MEMGETOOBSEL");
 					close (fd);
@@ -286,14 +289,11 @@ int main(int argc, char **argv)
 				}
 				oobinfochanged = 1;
 				break;
-
-			case 0:
-				oobinfochanged = 2;
-				break;
 			default:
 				perror ("MTDFILEMODE");
 				close (fd);
 				exit (1);
+			}
 		}
 	}
 
--- mtd-utils.git.orig/nanddump.c
+++ mtd-utils.git/nanddump.c
@@ -170,7 +170,7 @@ int main(int argc, char **argv)
 {
 	unsigned long ofs, end_addr = 0;
 	unsigned long long blockstart = 1;
-	int i, fd, ofd, bs, badblock = 0;
+	int ret, i, fd, ofd, bs, badblock = 0;
 	struct mtd_oob_buf oob = {0, 16, oobbuf};
 	mtd_info_t meminfo;
 	char pretty_buf[80];
@@ -206,9 +206,12 @@ int main(int argc, char **argv)
 	oob.length = meminfo.oobsize;
 
 	if (noecc)  {
-		switch (ioctl(fd, MTDFILEMODE, (void *) MTD_MODE_RAW)) {
-
-			case -ENOTTY:
+		ret = ioctl(fd, MTDFILEMODE, (void *) MTD_MODE_RAW);
+		if (ret == 0) {
+			oobinfochanged = 2;
+		} else {
+			switch (errno) {
+			case ENOTTY:
 				if (ioctl (fd, MEMGETOOBSEL, &old_oobinfo) != 0) {
 					perror ("MEMGETOOBSEL");
 					close (fd);
@@ -221,14 +224,11 @@ int main(int argc, char **argv)
 				}
 				oobinfochanged = 1;
 				break;
-
-			case 0:
-				oobinfochanged = 2;
-				break;
 			default:
 				perror ("MTDFILEMODE");
 				close (fd);
 				exit (1);
+			}
 		}
 	} else {