[PATCH] commands/crc: assert newline after output with big offsets

[Uwe Kleine-König]

This fixes

	barebox at Very long board name:/ crc32 -f /dev/mem 0x83f00000+0xfff
	CRC32 for /dev/mem 0x83fff000 ... 0x83fffffe ==> 0xa080584bbarebox at Very long board name:/

The problem here was that the return value of
lseek(fd, 0x83f00000, SEEK_SET) (which is 0x83f00000) was casted to an
int (which is -2081423360), returned to do_crc and interpreted as
error there without yielding another error message.

This also makes

	crc32 -f /dev/mem 0xffffffff+0x1

die on a NULL pointer exception instead of reporting:

	lseek: No error

:-)

Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
On Wed, Jun 27, 2012 at 10:25:37AM +0200, Sascha Hauer wrote:
> On Wed, Jun 27, 2012 at 10:13:13AM +0200, Uwe Kleine-König wrote:
> > Without this patch the next command prompt starts directly after the
> > calculated check sum. While at it also fix the coding style.
> 
> Under which conditions does this happen? The newline should be appended in
> do_crc()
You're right, my patch was not correct. This version should do the right
thing now.

Best regards
Uwe

 commands/crc.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/commands/crc.c b/commands/crc.c
index df22941..10a2900 100644
--- a/commands/crc.c
+++ b/commands/crc.c
@@ -47,9 +47,12 @@ static int file_crc(char* filename, ulong start, ulong size, ulong *crc,
 	}
 
 	if (start > 0) {
-		ret = lseek(fd, start, SEEK_SET);
-		if (ret == -1) {
+		off_t lseek_ret;
+		errno = 0;
+		lseek_ret = lseek(fd, start, SEEK_SET);
+		if (lseek_ret == (off_t)-1 && errno) {
 			perror("lseek");
+			ret = -1;
 			goto out;
 		}
 	}
-- 
1.7.10