From early days, Nicira used the --with-build-number option to configure to
stamp our internal builds. We've since switched to another scheme, so
this option is obsolete.
Good riddance.
Signed-off-by: Ben Pfaff <blp@nicira.com>
bitwise_copy() is generally useful so make it a general utility function.
Also add a comment.
Upcoming commits will introduce users for the new functions.
Signed-off-by: Ben Pfaff <blp@nicira.com>
There are a few loose ends here. First, learning actions cause too much
flow revalidation. Upcoming commits will fix that problem. The following
additional issues have not yet been addressed:
* Resource limits: nothing yet limits the maximum number of flows that
can be learned. It is possible to exhaust all system memory.
* Age reporting: there is no way to find out how soon a learned table
entry is due to be evicted.
To try this action out, here's a recipe for a very simple-minded MAC
learning switch. It uses a 10-second MAC expiration time to make it easier
to see what's going on:
ovs-vsctl del-controller br0
ovs-ofctl del-flows br0
ovs-ofctl add-flow br0 "table=0 actions=learn(table=1, hard_timeout=10, \
NXM_OF_VLAN_TCI[0..11], NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[], \
output:NXM_OF_IN_PORT[]), resubmit(,1)"
ovs-ofctl add-flow br0 "table=1 priority=0 actions=flood"
You can then dump the MAC learning table with:
ovs-ofctl dump-flows br0 table=1
We had these functions scattered around the source tree anyway. packets.h
is a good place to centralize them.
I do plan to introduce some additional callers.
exit(EXIT_FAILURE) will make a monitoring process (the one created by
--monitor) think that it should exit. But the most likely reason for
out_of_memory() to be called is a bug: probably, the process is trying
to allocate more memory than there is available address space, e.g.
something like malloc(-1). So it's better, in my opinion, to call abort()
instead, so that the monitor process restarts the daemon and we are more
likely to stay alive and, in addition, get a core dump and a useful bug
report.
I decided to implement a new general-purpose function for this purpose in
case we run into other similar situations in the future.
(I haven't actually run into this problem in practice. This commit is
just speculation about what is better behavior.)
Static analyzers hate strncpy(). This new function shares its property of
initializing an entire buffer, without its nasty habit of failing to
null-terminate long strings.
Coverity #10697,10696,10695,10694,10693,10692,10691,10690.
The blind replacement of strncpy() by ovs_strlcpy() is risky because
strncpy() never reads more bytes from its source string than necessary to
write its destination string, but ovs_strlcpy() and the OpenBSD function
that inspired it both read the entire source string. This avoids that
problem.
Given that change, we can use ovs_strlcpy() in a few more places, and
this commit does that too.
Coverity #10697,10696,10695,10694,10693,10692,10691,10690.
Many OVS functions return 0, EOF, or errno. There are several places in the
codebase where a return value is converted to a string. All must decide whether
the return value is set, and if it is, whether it is an errno value, EOF, or
otherwise invalid. This commit consolidates that code.
Reviewed by Ben Pfaff.
Until now, the collection of coverage counters supported by a given OVS
program was not specific to that program. That means that, for example,
even though ovs-dpctl does not have anything to do with mac_learning, it
still has a coverage counter for it. This is confusing, at best.
This commit fixes the problem on some systems, in particular on ones that
use GCC and the GNU linker. It uses the feature of the GNU linker
described in its manual as:
If an orphaned section's name is representable as a C identifier then
the linker will automatically see PROVIDE two symbols: __start_SECNAME
and __end_SECNAME, where SECNAME is the name of the section. These
indicate the start address and end address of the orphaned section
respectively.
Systems that don't support these features retain the earlier behavior.
This commit also fixes the annoyance that files that include coverage
counters must be listed on COVERAGE_FILES in lib/automake.mk.
This commit also fixes the annoyance that modifying any source file that
includes a coverage counter caused all programs that link against
libopenvswitch.a to relink, even programs that the source file was not
linked into. For example, modifying ofproto/ofproto.c (which includes
coverage counters) caused tests/test-aes128 to relink, even though
test-aes128 does not link again ofproto.o.
Adding a macro to define the vlog module in use adds a level of
indirection, which makes it easier to change how the vlog module must be
defined. A followup commit needs to do that, so getting these widespread
changes out of the way first should make that commit easier to review.
Some systems complain when certain functions' return values are not
checked. This commit fixes those warnings.
Creating ignore() function suggested by Ben Pfaff.
