$SUBJ: "Implement" On 05/04/2018 04:21 PM, Stefan Berger wrote:
Implement virFileReadOffsetQuiet() that reads a given maximum number of bytes into a buffer that will be allocated. The reading starts from a given offset.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> --- src/libvirt_private.syms | 1 + src/util/virfile.c | 14 +++++++++++++- src/util/virfile.h | 3 +++ 3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 92b5e0f..f2a4921 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -1807,6 +1807,7 @@ virFileReadHeaderFD; virFileReadHeaderQuiet; virFileReadLimFD; virFileReadLink; +virFileReadOffsetQuiet; virFileReadValueBitmap; virFileReadValueInt; virFileReadValueScaledInt; diff --git a/src/util/virfile.c b/src/util/virfile.c index 40f106d..526b9ad 100644 --- a/src/util/virfile.c +++ b/src/util/virfile.c @@ -1432,12 +1432,18 @@ virFileReadAll(const char *path, int maxlen, char **buf) }
Two blank lines between functions is the new normal...
int -virFileReadAllQuiet(const char *path, int maxlen, char **buf) +virFileReadOffsetQuiet(const char *path, off_t offset, + int maxlen, char **buf)
...and each argument on it's own line...
{ int fd = open(path, O_RDONLY); if (fd < 0) return -errno;
+ if (offset > 0 && lseek(fd, offset, SEEK_SET) < 0) { + VIR_FORCE_CLOSE(fd); + return -errno; + } + int len = virFileReadLimFD(fd, maxlen, buf); VIR_FORCE_CLOSE(fd); if (len < 0) @@ -1446,6 +1452,12 @@ virFileReadAllQuiet(const char *path, int maxlen, char **buf) return len; }
+int +virFileReadAllQuiet(const char *path, int maxlen, char **buf)
... here too (as well as the 2 empty lines on either side since we're touching the code). With the adjustments, Reviewed-by: John Ferlan <jferlan@redhat.com> but I do have some other concerns later in patch 7 when this is used as to whether it's necessary. John
+{ + return virFileReadOffsetQuiet(path, 0, maxlen, buf); +} + /* Read @file into preallocated buffer @buf of size @len. * Return value is -errno in case of errors and size * of data read (no trailing zero) in case of success. diff --git a/src/util/virfile.h b/src/util/virfile.h index 341320b..13d3cf6 100644 --- a/src/util/virfile.h +++ b/src/util/virfile.h @@ -137,6 +137,9 @@ int virFileReadLimFD(int fd, int maxlen, char **buf) ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(3); int virFileReadAll(const char *path, int maxlen, char **buf) ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3); +int virFileReadOffsetQuiet(const char *path, off_t offset, + int maxlen, char **buf) + ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(4); int virFileReadAllQuiet(const char *path, int maxlen, char **buf) ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3); int virFileReadBufQuiet(const char *file, char *buf, int len)