build: extract library versions from notmuch.h

- Make lib/notmuch.h the canonical location for the library versioning
information.

- Since the release-check should never fail now, remove it to reduce
complexity.

- Make the version numbers in notmuch.h consistent with the (now
  deleted) ones in lib/Makefile.local

configure

@@ -324,6 +324,35 @@ EOF
     exit 1
 fi
 
+printf "Reading libnotmuch version from source..."
+cat > _libversion.c <<EOF
+#include <stdio.h>
+#include "lib/notmuch.h"
+int main(void) {
+    printf("libnotmuch_version_major=%d\n",
+		LIBNOTMUCH_MAJOR_VERSION);
+    printf("libnotmuch_version_minor=%d\n",
+		LIBNOTMUCH_MINOR_VERSION);
+    printf("libnotmuch_version_release=%d\n",
+		LIBNOTMUCH_MICRO_VERSION);
+    return 0;
+}
+EOF
+if ${CC} ${CFLAGS} _libversion.c -o _libversion > /dev/null 2>&1 && \
+       ./_libversion > _libversion.sh && . ./_libversion.sh
+then
+    printf  "OK"
+else
+    cat <<EOF
+
+*** Error: Reading lib/notmuch.h failed.
+Please try running configure again in a clean environment, and if the
+problem persists, report a bug.
+EOF
+    rm -f _libversion _libversion.c _libversion.sh
+    exit 1
+fi
+
 if pkg-config --version > /dev/null 2>&1; then
     have_pkg_config=1
 else
@@ -809,7 +838,7 @@ for flag in -Wmissing-declarations; do
 done
 printf "\n\t${WARN_CFLAGS}\n"
 
-rm -f minimal minimal.c
+rm -f minimal minimal.c _libversion.c _libversion _libversion.sh
 
 # construct the Makefile.config
 cat > Makefile.config <<EOF
@@ -847,6 +876,28 @@ vpath Makefile.% \$(srcdir)
 vpath %.py \$(srcdir)
 vpath %.rst \$(srcdir)
 
+# Library versions (used to make SONAME)
+# The major version of the library interface. This will control the soname.
+# As such, this number must be incremented for any incompatible change to
+# the library interface, (such as the deletion of an API or a major
+# semantic change that breaks formerly functioning code).
+#
+LIBNOTMUCH_VERSION_MAJOR = ${libnotmuch_version_major}
+
+# The minor version of the library interface. This should be incremented at
+# the time of release for any additions to the library interface,
+# (and when it is incremented, the release version of the library should
+#  be reset to 0).
+LIBNOTMUCH_VERSION_MINOR = ${libnotmuch_version_minor}
+
+# The release version the library interface. This should be incremented at
+# the time of release if there have been no changes to the interface, (but
+# simply compatible changes to the implementation).
+LIBNOTMUCH_VERSION_RELEASE = ${libnotmuch_version_release}
+
+# These are derived from the VERSION macros in lib/notmuch.h so
+# if you have to change them, something is wrong.
+
 # The C compiler to use
 CC = ${CC}
 

devel/release-checks.sh

@@ -88,38 +88,6 @@ case $VERSION in
 	*)	verfail "'$VERSION' is a single number" ;;
 esac
 
-echo -n "Checking that LIBNOTMUCH version macros & variables match ... "
-# lib/notmuch.h
-LIBNOTMUCH_MAJOR_VERSION=broken
-LIBNOTMUCH_MINOR_VERSION=broken
-LIBNOTMUCH_MICRO_VERSION=broken
-# lib/Makefile.local
-LIBNOTMUCH_VERSION_MAJOR=borken
-LIBNOTMUCH_VERSION_MINOR=borken
-LIBNOTMUCH_VERSION_RELEASE=borken
-
-eval `awk 'NF == 3 && $1 == "#define" && $2 ~ /^LIBNOTMUCH_[A-Z]+_VERSION$/ \
-	&& $3 ~ /^[0-9]+$/ { print $2 "=" $3 }' lib/notmuch.h`
-
-eval `awk 'NF == 3 && $1 ~ /^LIBNOTMUCH_VERSION_[A-Z]+$/ && $2 == "=" \
-	&& $3 ~ /^[0-9]+$/ { print $1 "=" $3 }' lib/Makefile.local`
-
-
-check_version_component ()
-{
-	eval local v1=\$LIBNOTMUCH_$1_VERSION
-	eval local v2=\$LIBNOTMUCH_VERSION_$2
-	if [ $v1 != $v2 ]
-	then	append_emsg "LIBNOTMUCH_$1_VERSION ($v1) does not equal LIBNOTMUCH_VERSION_$2 ($v2)"
-	fi
-}
-
-old_emsg_count=$emsg_count
-check_version_component MAJOR MAJOR
-check_version_component MINOR MINOR
-check_version_component MICRO RELEASE
-[ $old_emsg_count = $emsg_count ] && echo Yes. || echo No.
-
 echo -n "Checking that this is Debian package for notmuch... "
 read deb_notmuch deb_version rest < debian/changelog
 if [ "$deb_notmuch" = 'notmuch' ]

lib/Makefile.local

@@ -1,26 +1,5 @@
 # -*- makefile -*-
 
-# The major version of the library interface. This will control the soname.
-# As such, this number must be incremented for any incompatible change to
-# the library interface, (such as the deletion of an API or a major
-# semantic change that breaks formerly functioning code).
-#
-LIBNOTMUCH_VERSION_MAJOR = 4
-
-# The minor version of the library interface. This should be incremented at
-# the time of release for any additions to the library interface,
-# (and when it is incremented, the release version of the library should
-#  be reset to 0).
-LIBNOTMUCH_VERSION_MINOR = 3
-
-# The release version the library interface. This should be incremented at
-# the time of release if there have been no changes to the interface, (but
-# simply compatible changes to the implementation).
-LIBNOTMUCH_VERSION_RELEASE = 0
-
-# Note: Don't forget to change the VERSION macros in notmuch.h when
-# any of the above change.
-
 ifeq ($(PLATFORM),MACOSX)
 LIBRARY_SUFFIX = dylib
 # On OS X, library version numbers go before suffix.

lib/notmuch.h

@@ -56,7 +56,7 @@ NOTMUCH_BEGIN_DECLS
  * version in Makefile.local.
  */
 #define LIBNOTMUCH_MAJOR_VERSION	4
-#define LIBNOTMUCH_MINOR_VERSION	2
+#define LIBNOTMUCH_MINOR_VERSION	3
 #define LIBNOTMUCH_MICRO_VERSION	0
 
 #define NOTMUCH_DEPRECATED(major,minor) \