5:12 p.m.
On 9/24/19 4:07 PM, Richard W.M. Jones wrote:
Use a simple bash script to generate the protostrings.c functions.
Remove the extern decls from the nbd-protocol.h file which were used
previously in the generation of this file. They have been moved to a
new internal header called "protostrings.h".
---
common/protocol/Makefile.am | 8 ++-
...tostrings.sed => generate-protostrings.sh} | 56 +++++++++++--------
Wow - git thinks .sed and .sh are similar! Probably more a case of the
boilerplate copyright being identical, and the rest of the file being
short enough in spite of more-or-less wholesale rewrite.
common/protocol/nbd-protocol.h | 10 ----
common/protocol/protostrings.h | 51 +++++++++++++++++
plugins/nbd/nbd-standalone.c | 1 +
server/protocol-handshake-newstyle.c | 1 +
server/protocol.c | 1 +
7 files changed, 91 insertions(+), 37 deletions(-)
+protostrings.c: nbd-protocol.h generate-protostrings.sh Makefile
rm -f $@ $@-t
- $(SED) -n -f $(srcdir)/protostrings.sed < $< > $@-t
+ SED=$(SED) $(srcdir)/generate-protostrings.sh > $@-t
Okay, not just a wholesale rewrite, but keeping a sed invocation while
wrapping in even more logic.
--- a/common/protocol/protostrings.sed
+++ b/common/protocol/generate-protostrings.sh
@@ -1,5 +1,6 @@
+#!/usr/bin/env bash
# nbdkit
-# Copyright (C) 2018 Red Hat Inc.
+# Copyright (C) 2018-2019 Red Hat Inc.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
@@ -29,30 +30,37 @@
# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
-# Generate the protostrings.c file from nbd-protocol.h.
+# The header.
+cat <<'EOF'
+/* Generated from nbd-protocol.h by generate-protostrings.sh. */
Worth using:
cat << EOF
/* Generated from nbd-protocol.h by $0. */
? Or is that too prone to non-reproducible builds if $0 includes a full
path (would $(basename -- $0) fix that)?
-# Prologue.
-1i\
-/* Generated from nbd-protocol.h by protostrings.sed. */\
-\#include "nbd-protocol.h"\
+#include "nbd-protocol.h"
+EOF
We don't have a mention of license/copyright in the generated file
(other than implicitly assuming the same license as in the source files
that generated it). Is now a good time to spit one out as part of our
prologue?
-# Match the precise sections of the source file.
-/^extern const char \*name_of_/,/^$/ {
+declare -A functions=(
+ [global_flag]=NBD_FLAG_FIXED_NEWSTYLE
+ [flag]=NBD_FLAG_HAS_FLAGS
+ [opt]=NBD_OPT_EXPORT_NAME
+ [rep]=NBD_REP_ACK
+ [info]=NBD_INFO_EXPORT
+ [reply]=NBD_REPLY_FLAG_DONE
+ [reply_type]=NBD_REPLY_TYPE_NONE
+ [cmd]=NBD_CMD_READ
+ [cmd_flag]=NBD_CMD_FLAG_FUA
+ [error]=NBD_SUCCESS
+)
Definite bashism. That's fine, given the #! line.
- # Convert extern function prototype into a definition.
- s/extern \(const char \*name_of_.*\) (int);/\1 (int fl) {\
- switch (fl) {/;
-
- # Convert #define lines into cases.
- s/^#define \([_A-Z]*\).*/ case \1: return "\1\";/;
-
- # Append closing brace.
- s/^$/ default: return "unknown";\
- }\
-}/;
-
- # Print pattern buffer.
- p;
-
-}
+# Generate each 'const char *name_of_nbd_<fn>'
+for fn in "${!functions[@]}"; do
Is this going to be deterministic, or are we at the mercy of bash's
hashing? Should we sort the list to guarantee stable output order?
+ echo 'extern const char *'
+ echo "name_of_nbd_$fn (int fl)"
+ echo '{'
+ echo ' switch (fl) {'
+ $SED -n "/^#define ${functions[$fn]}/,/^$/p" nbd-protocol.h |
+ $SED 's/^#define \([_A-Z]*\).*/ case \1:\n return
"\1\";/'
+ echo ' default: return "unknown";'
+ echo ' }'
+ echo '}'
+ echo
+done
No sanity checking that $# was 0, but for an internal-only build script,
that probably doesn't matter. Looks like a sane conversion.
diff --git a/plugins/nbd/nbd-standalone.c
b/plugins/nbd/nbd-standalone.c
index a6779a4..1789e39 100644
--- a/plugins/nbd/nbd-standalone.c
+++ b/plugins/nbd/nbd-standalone.c
@@ -54,6 +54,7 @@
#include <nbdkit-plugin.h>
#include "nbd-protocol.h"
+#include "protostrings.h"
Should we switch from "nbd-protocol.h" to <nbd-protocol.h> at some point
in the series, to reflect our intent of installing it? But doesn't
affect this patch.
ACK
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org