libxfs: handle short reads in libxfs_readbufr

Copy the code from libxfs_writebufr to handle short reads, and also
tidy up a formatting issue found in the libxfs_writebufr copy.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
index 2c4da8c6b52df4c83128ca7db31203f8137e74be..59cd82bb6b09596ca430b41122935cae700f0c2d 100644 (file)
--- a/libxfs/rdwr.c
+++ b/libxfs/rdwr.c
@@ -455,16 +455,24 @@ libxfs_readbufr(dev_t dev, xfs_daddr_t blkno, xfs_buf_t *bp, int len, int flags)
        int     fd = libxfs_device_to_fd(dev);
        int     bytes = BBTOB(len);
        int     error;
+       int     sts;
 
        ASSERT(BBTOB(len) <= bp->b_bcount);
 
-       if (pread64(fd, bp->b_addr, bytes, LIBXFS_BBTOOFF64(blkno)) < 0) {
+       sts = pread64(fd, bp->b_addr, bytes, LIBXFS_BBTOOFF64(blkno));
+       if (sts < 0) {
                error = errno;
                fprintf(stderr, _("%s: read failed: %s\n"),
                        progname, strerror(error));
                if (flags & LIBXFS_EXIT_ON_FAILURE)
                        exit(1);
                return error;
+       } else if (sts != bytes) {
+               fprintf(stderr, _("%s: error - read only %d of %d bytes\n"),
+                       progname, sts, bytes);
+               if (flags & LIBXFS_EXIT_ON_FAILURE)
+                       exit(1);
+               return EIO;
        }
 #ifdef IO_DEBUG
        printf("%lx: %s: read %u bytes, blkno=%llu(%llu), %p\n",
@@ -510,8 +518,7 @@ libxfs_writebufr(xfs_buf_t *bp)
                if (bp->b_flags & LIBXFS_B_EXIT)
                        exit(1);
                return error;
-       }
-       else if (sts != bp->b_bcount) {
+       } else if (sts != bp->b_bcount) {
                fprintf(stderr, _("%s: error - wrote only %d of %d bytes\n"),
                        progname, sts, bp->b_bcount);
                if (bp->b_flags & LIBXFS_B_EXIT)