local.c: when target buffer is too small, fail

Fix #357 If a target buffer is too small, right now, we try to put a partial fill in the buffer, and return sucess (which is wrong). Now we will return EFBIG, and leave the target buffer empty. This will make the local backends the same as the otherbackends. Signed-off-by: Robin Getz <[email protected]>
analogdevicesinc · Oct 9, 2020 · 67273fc · 67273fc
1 parent 80ed865
commit 67273fc
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/local.c b/local.c
@@ -706,10 +706,16 @@ static ssize_t local_read_dev_attr(const struct iio_device *dev,
 		return -errno;
 
 	ret = fread(dst, 1, len, f);
+
+	/* if we didn't read the entire file, fail */
+	if (!feof(f))
+		ret = -EFBIG;
+
 	if (ret > 0)
 		dst[ret - 1] = '\0';
 	else
 		dst[0] = '\0';
+
 	fflush(f);
 	if (ferror(f))
 		ret = -errno;