Re: [PATCH v6 08/18] pesto: Introduce stub configuration tool

[Stefano Brivio <sbrivio@redhat.com>]

On Mon, 4 May 2026 12:51:02 +0200
Laurent Vivier <lvivier@redhat.com> wrote:

> On 5/3/26 23:55, Stefano Brivio wrote:
> > From: David Gibson <david@gibson.dropbear.id.au>
> > 
> > Build a new "pesto" binary, which will become the tool to update a running
> > passt/pasta's configuration.  For now, we just build a stub binary which
> > sets up a basic environment, parses trivial command line options but does
> > nothing else.
> > 
> > Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> > Signed-off-by: Stefano Brivio <sbrivio@redhat.com>  
> 
> Reviewed-by: Laurent Vivier <lvivier@redhat.com>
> 
> One little nit below
> 
> > ---
> >   .gitignore |   2 +
> >   Makefile   |  42 +++++++++++------
> >   common.h   |  24 ++++++++++
> >   pesto.1    |  46 +++++++++++++++++++
> >   pesto.c    | 132 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >   pesto.h    |  12 +++++
> >   util.h     |  12 +----
> >   7 files changed, 244 insertions(+), 26 deletions(-)
> >   create mode 100644 common.h
> >   create mode 100644 pesto.1
> >   create mode 100644 pesto.c
> >   create mode 100644 pesto.h
> > 
> > diff --git a/.gitignore b/.gitignore
> > index 3c16adc..3e40d9f 100644
> > --- a/.gitignore
> > +++ b/.gitignore
> > @@ -4,9 +4,11 @@
> >   /pasta
> >   /pasta.avx2
> >   /passt-repair
> > +/pesto
> >   /qrap
> >   /pasta.1
> >   /seccomp.h
> > +/seccomp_pesto.h
> >   /seccomp_repair.h
> >   /c*.json
> >   README.plain.md
> > diff --git a/Makefile b/Makefile
> > index 7875d23..030681b 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -47,19 +47,21 @@ PASST_SRCS = arch.c arp.c bitmap.c checksum.c conf.c dhcp.c dhcpv6.c \
> >   	vhost_user.c virtio.c vu_common.c
> >   QRAP_SRCS = qrap.c
> >   PASST_REPAIR_SRCS = passt-repair.c
> > -SRCS = $(PASST_SRCS) $(QRAP_SRCS) $(PASST_REPAIR_SRCS)
> > -
> > -MANPAGES = passt.1 pasta.1 qrap.1 passt-repair.1
> > -
> > -PASST_HEADERS = arch.h arp.h bitmap.h checksum.h conf.h dhcp.h dhcpv6.h \
> > -	epoll_ctl.h flow.h fwd.h fwd_rule.h flow_table.h icmp.h icmp_flow.h \
> > -	inany.h iov.h ip.h isolation.h lineread.h log.h migrate.h ndp.h \
> > -	netlink.h packet.h passt.h pasta.h pcap.h pif.h repair.h serialise.h \
> > -	siphash.h tap.h tcp.h tcp_buf.h tcp_conn.h tcp_internal.h tcp_splice.h \
> > -	tcp_vu.h udp.h udp_flow.h udp_internal.h udp_vu.h util.h vhost_user.h \
> > -	virtio.h vu_common.h
> > +PESTO_SRCS = pesto.c
> > +SRCS = $(PASST_SRCS) $(QRAP_SRCS) $(PASST_REPAIR_SRCS) $(PESTO_SRCS)
> > +
> > +MANPAGES = passt.1 pasta.1 pesto.1 qrap.1 passt-repair.1
> > +
> > +PASST_HEADERS = arch.h arp.h bitmap.h checksum.h common.h conf.h dhcp.h \
> > +	dhcpv6.h epoll_ctl.h flow.h fwd.h fwd_rule.h flow_table.h icmp.h \
> > +	icmp_flow.h inany.h iov.h ip.h isolation.h lineread.h log.h migrate.h \
> > +	ndp.h netlink.h packet.h passt.h pasta.h pcap.h pesto.h pif.h repair.h \
> > +	serialise.h siphash.h tap.h tcp.h tcp_buf.h tcp_conn.h tcp_internal.h \
> > +	tcp_splice.h tcp_vu.h udp.h udp_flow.h udp_internal.h udp_vu.h util.h \
> > +	vhost_user.h virtio.h vu_common.h
> >   QRAP_HEADERS = arp.h ip.h passt.h util.h
> >   PASST_REPAIR_HEADERS = linux_dep.h
> > +PESTO_HEADERS = common.h pesto.h
> >   
> >   C := \#include <sys/random.h>\nint main(){int a=getrandom(0, 0, 0);}
> >   ifeq ($(shell printf "$(C)" | $(CC) -S -xc - -o - >/dev/null 2>&1; echo $$?),0)
> > @@ -78,7 +80,7 @@ docdir		?= $(datarootdir)/doc/passt
> >   mandir		?= $(datarootdir)/man
> >   man1dir		?= $(mandir)/man1
> >   
> > -BASEBIN = passt qrap passt-repair
> > +BASEBIN = passt qrap passt-repair pesto
> >   ifeq ($(TARGET_ARCH),x86_64)
> >   BASEBIN += passt.avx2
> >   endif
> > @@ -100,6 +102,9 @@ seccomp.h: seccomp.sh $(PASST_SRCS) $(PASST_HEADERS)
> >   seccomp_repair.h: seccomp.sh $(PASST_REPAIR_SRCS) $(PASST_REPAIR_HEADERS)
> >   	@ ARCH="$(TARGET_ARCH)" CC="$(CC)" ./seccomp.sh seccomp_repair.h $(PASST_REPAIR_SRCS)
> >   
> > +seccomp_pesto.h: seccomp.sh $(PESTO_SRCS)
> > +	@ ARCH="$(TARGET_ARCH)" CC="$(CC)" ./seccomp.sh seccomp_pesto.h $(PESTO_SRCS)
> > +
> >   $(BASEBIN): %:
> >   	$(CC) $(BASE_CPPFLAGS) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) $(filter %.c,$^) -o $@
> >   
> > @@ -116,6 +121,8 @@ qrap: $(QRAP_SRCS) $(QRAP_HEADERS)
> >   
> >   passt-repair: $(PASST_REPAIR_SRCS) $(PASST_REPAIR_HEADERS) seccomp_repair.h
> >   
> > +pesto: $(PESTO_SRCS) $(PESTO_HEADERS) seccomp_pesto.h
> > +
> >   valgrind: EXTRA_SYSCALLS += rt_sigprocmask rt_sigtimedwait rt_sigaction	\
> >   			    rt_sigreturn getpid gettid kill clock_gettime \
> >   			    mmap|mmap2 munmap open unlink gettimeofday futex \
> > @@ -126,7 +133,7 @@ valgrind: all
> >   
> >   .PHONY: clean
> >   clean:
> > -	$(RM) $(BIN) *~ *.o seccomp.h seccomp_repair.h pasta.1 \
> > +	$(RM) $(BIN) *~ *.o seccomp.h seccomp_repair.h seccomp_pesto.h pasta.1 \
> >   		passt.tar passt.tar.gz *.deb *.rpm \
> >   		passt.pid README.plain.md
> >   
> > @@ -183,7 +190,8 @@ docs: README.md
> >   CLANG_TIDY = clang-tidy
> >   CLANG_TIDY_FLAGS = -DCLANG_TIDY_58992
> >   
> > -clang-tidy: passt.clang-tidy passt-repair.clang-tidy qrap.clang-tidy
> > +clang-tidy: passt.clang-tidy passt-repair.clang-tidy pesto.clang-tidy \
> > +	qrap.clang-tidy
> >   
> >   .PHONY: %.clang-tidy
> >   %.clang-tidy:
> > @@ -191,6 +199,7 @@ clang-tidy: passt.clang-tidy passt-repair.clang-tidy qrap.clang-tidy
> >   
> >   passt.clang-tidy: $(PASST_SRCS) $(PASST_HEADERS) seccomp.h
> >   passt-repair.clang-tidy: $(PASST_REPAIR_SRCS) $(PASST_REPAIR_HEADERS) seccomp_repair.h
> > +pesto.clang-tidy: $(PESTO_SRCS) $(PESTO_HEADERS) seccomp_pesto.h
> >   qrap.clang-tidy: $(QRAP_SRCS) $(QRAP_HEADERS)
> >   
> >   CPPCHECK = cppcheck
> > @@ -206,7 +215,7 @@ CPPCHECK_FLAGS = --std=c11 --error-exitcode=1 --enable=all --force	\
> >   	--suppress=unusedStructMember					\
> >   	 -D CPPCHECK_6936
> >   
> > -cppcheck: passt.cppcheck passt-repair.cppcheck qrap.cppcheck
> > +cppcheck: passt.cppcheck passt-repair.cppcheck pesto.cppcheck qrap.cppcheck
> >   
> >   .PHONY: %.cppcheck
> >   %.cppcheck:
> > @@ -215,6 +224,9 @@ cppcheck: passt.cppcheck passt-repair.cppcheck qrap.cppcheck
> >   passt.cppcheck: $(PASST_SRCS) $(PASST_HEADERS) seccomp.h
> >   passt-repair.cppcheck: $(PASST_REPAIR_SRCS) $(PASST_REPAIR_HEADERS) seccomp_repair.h
> >   
> > +pesto.cppcheck: CPPCHECK_FLAGS += --suppress=unmatchedSuppression
> > +pesto.cppcheck: $(PESTO_SRCS) $(PESTO_HEADERS) seccomp_pesto.h
> > +
> >   qrap.cppcheck: BASE_CPPFLAGS += -DARCH=\"$(TARGET_ARCH)\"
> >   qrap.cppcheck: CPPCHECK_FLAGS += --suppress=unusedFunction
> >   qrap.cppcheck: $(QRAP_SRCS) $(QRAP_HEADERS)
> > diff --git a/common.h b/common.h
> > new file mode 100644
> > index 0000000..a9c115a
> > --- /dev/null
> > +++ b/common.h
> > @@ -0,0 +1,24 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later
> > + * Copyright Red Hat
> > + * Author: David Gibson <david@gibson.dropbear.id.au>
> > + *
> > + * Definitions used by both passt/pasta and other tools
> > + */
> > +
> > +#ifndef COMMON_H
> > +#define COMMON_H
> > +
> > +#include <string.h>
> > +
> > +#define VERSION_BLOB							       \
> > +	VERSION "\n"							       \
> > +	"Copyright Red Hat\n"						       \
> > +	"GNU General Public License, version 2 or later\n"		       \
> > +	"  <https://www.gnu.org/licenses/old-licenses/gpl-2.0.html>\n"	       \
> > +	"This is free software: you are free to change and redistribute it.\n" \
> > +	"There is NO WARRANTY, to the extent permitted by law.\n\n"
> > +
> > +/* FPRINTF() intentionally silences cert-err33-c clang-tidy warnings */
> > +#define FPRINTF(f, ...)	(void)fprintf(f, __VA_ARGS__)
> > +
> > +#endif /* _COMMON_H */  
> 
> Why "_COMMON_H" and not "COMMON_H"?

I think it was... common, a long time ago, to prefix include guards
with underscores (perhaps in the Linux kernel, I don't remember). I also
happened to write some code with those and fixed it just before sending
out patches.

Somewhat curiously, that's also the case for lineread.h (without the
underscore in the actual include guard name, just in the comment at the
end), and I missed that during review as well:

  https://archives.passt.top/passt-dev/20220623113143.538e9266@elisabeth/

Anyway, fixed in v7.

-- 
Stefano