| Message ID | 1362044529-511-1-git-send-email-u.kleine-koenig@pengutronix.de |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 2013-02-28 at 10:42 +0100, Uwe Kleine-König wrote: > When doing something like: > > { printf "\xff"; printf "\xfe"; } | flash_otp_write -u /dev/mtd0 0 > > flash_otp_write might see only a single byte when reading from stdin for > the first tim. In this case (and without this patch) it pads to > $writesize with '\xff's and writes that out. In the next iteration it > reads the 2nd byte, pads and writes again. So the 2nd byte is written to > offset $writesize instead of 1. > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Pushed both to mtd-utils.git, thanks!
diff --git a/flash_otp_write.c b/flash_otp_write.c index 41cf1c5..0aa872e 100644 --- a/flash_otp_write.c +++ b/flash_otp_write.c @@ -15,6 +15,23 @@ #include <mtd/mtd-user.h> +ssize_t xread(int fd, void *buf, size_t count) +{ + ssize_t ret, done = 0; + +retry: + ret = read(fd, buf + done, count - done); + if (ret < 0) + return ret; + + done += ret; + + if (ret == 0 /* EOF */ || done == count) + return done; + else + goto retry; +} + int main(int argc,char *argv[]) { int fd, val, ret, size, wrote, len; @@ -66,7 +83,7 @@ int main(int argc,char *argv[]) len = 256; wrote = 0; - while ((size = read(0, buf, len))) { + while ((size = xread(0, buf, len))) { if (size < 0) { perror("read()"); return errno;
When doing something like: { printf "\xff"; printf "\xfe"; } | flash_otp_write -u /dev/mtd0 0 flash_otp_write might see only a single byte when reading from stdin for the first tim. In this case (and without this patch) it pads to $writesize with '\xff's and writes that out. In the next iteration it reads the 2nd byte, pads and writes again. So the 2nd byte is written to offset $writesize instead of 1. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> --- flash_otp_write.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-)