Add LMDB backend for RPMDB to RPM (from @n3npq in #281)

ci/Dockerfile

@@ -24,6 +24,7 @@ RUN dnf -y install \
   popt-devel \
   libarchive-devel \
   libdb-devel \
+  lmdb-devel \
   libselinux-devel \
   ima-evm-utils \
   libcap-devel \

configure.ac

@@ -581,6 +581,30 @@ AS_IF([test "$enable_ndb" = yes],[
 ])
 AM_CONDITIONAL([NDB], [test "$enable_ndb" = yes])
 
+#=================
+# Check for LMDB support
+AC_ARG_ENABLE([lmdb],
+              [AS_HELP_STRING([--enable-lmdb=@<:@yes/no/auto@:>@],
+                              [build with LMDB rpm database format support (default=auto)])],
+              [enable_lmdb="$enableval"],
+              [enable_lmdb=auto])
+
+AS_IF([test "x$enable_lmdb" != "xno"], [
+  PKG_CHECK_MODULES([LMDB], [lmdb], [have_lmdb=yes], [have_lmdb=no])
+  AS_IF([test "$enable_lmdb" = "yes"], [
+    if test "$have_lmdb" = "no"; then
+      AC_MSG_ERROR([--enable-lmdb specified, but not available])
+    fi
+  ])
+])
+
+if test "x$have_lmdb" = "xyes"; then
+  AC_DEFINE([WITH_LMDB], [1], [Define if LMDB is available])
+  LMDB_REQUIRES=lmdb
+  AC_SUBST(LMDB_REQUIRES)
+fi
+AM_CONDITIONAL([LMDB], [test "x$have_lmdb" = "xyes"])
+
 AM_GNU_GETTEXT_VERSION([0.16.1])
 AM_GNU_GETTEXT([external])
 AM_ICONV

lib/Makefile.am

@@ -7,6 +7,7 @@ AM_CPPFLAGS = -I$(top_builddir) -I$(top_srcdir) -I$(top_builddir)/include/
 AM_CPPFLAGS += @WITH_BEECRYPT_INCLUDE@
 AM_CPPFLAGS += @WITH_NSS_INCLUDE@
 AM_CPPFLAGS += @WITH_POPT_INCLUDE@
+AM_CPPFLAGS += $(LMDB_CFLAGS)
 AM_CPPFLAGS += -I$(top_srcdir)/misc
 AM_CPPFLAGS += -DLOCALEDIR="\"$(localedir)\""
 AM_CPPFLAGS += -DSYSCONFDIR="\"$(sysconfdir)\""
@@ -75,6 +76,13 @@ librpm_la_SOURCES += \
 	backend/ndb/rpmxdb.h
 endif
 
+if LMDB
+AM_CPPFLAGS += $(LMDB_CFLAGS)
+librpm_la_LIBADD += $(LMDB_LIBS)
+librpm_la_SOURCES += \
+	backend/lmdb.c
+endif
+
 tagtbl.C: Makefile.am $(srcdir)/rpmtag.h gentagtbl.sh
 	@AWK=${AWK} ${SHELL} $(srcdir)/gentagtbl.sh \
 		    	     $(srcdir)/rpmtag.h > $@.new && \

lib/backend/dbi.c

@@ -35,31 +35,55 @@ dbiIndex dbiNew(rpmdb rdb, rpmDbiTagVal rpmtag)
 static void
 dbDetectBackend(rpmdb rdb)
 {
-#ifdef ENABLE_NDB
     const char *dbhome = rpmdbHome(rdb);
     char *db_backend = rpmExpand("%{?_db_backend}", NULL);
+    char *path = NULL;
+
+#if defined(WITH_LMDB)
+    if (!strcmp(db_backend, "lmdb")) {
+	rdb->db_ops = &lmdb_dbops;
+    } else
+#endif
+#ifdef ENABLE_NDB
     if (!strcmp(db_backend, "ndb")) {
 	rdb->db_ops = &ndb_dbops;
-    } else {
+    } else
+#endif
+    {
 	rdb->db_ops = &db3_dbops;
+	if (*db_backend == '\0') {
+	    free(db_backend);
+	    db_backend = xstrdup("bdb");
+	}
     }
-    free(db_backend);
 
-    char *path = rstrscat(NULL, dbhome, "/Packages", NULL);
-    if (access(path, F_OK) == 0 && rdb->db_ops != &db3_dbops) {
-	rdb->db_ops = &db3_dbops;
-	rpmlog(RPMLOG_WARNING, _("Unexpected database format\n"));
+#if defined(WITH_LMDB)
+    path = rstrscat(NULL, dbhome, "/Packages.mdb", NULL);
+    if (access(path, F_OK) == 0 && rdb->db_ops != &lmdb_dbops) {
+	rdb->db_ops = &lmdb_dbops;
+	rpmlog(RPMLOG_WARNING, _("Found LMDB Packages.mdb database while attempting %s backend: using lmdb backend.\n"), db_backend);
     }
     free(path);
+#endif
+
+#ifdef ENABLE_NDB
     path = rstrscat(NULL, dbhome, "/Packages.db", NULL);
     if (access(path, F_OK) == 0 && rdb->db_ops != &ndb_dbops) {
 	rdb->db_ops = &ndb_dbops;
-	rpmlog(RPMLOG_WARNING, _("Unexpected database format\n"));
+	rpmlog(RPMLOG_WARNING, _("Found NDB Packages.db database while attempting %s backend: using ndb backend.\n"), db_backend);
     }
     free(path);
-#else
-    rdb->db_ops = &db3_dbops;
 #endif
+
+    path = rstrscat(NULL, dbhome, "/Packages", NULL);
+    if (access(path, F_OK) == 0 && rdb->db_ops != &db3_dbops) {
+	rdb->db_ops = &db3_dbops;
+	rpmlog(RPMLOG_WARNING, _("Found BDB Packages database while attempting %s backend: using bdb backend.\n"), db_backend);
+    }
+    free(path);
+
+    if (db_backend)
+	free(db_backend);
 }
 
 const char * dbiName(dbiIndex dbi)

lib/backend/dbi.h

@@ -257,6 +257,11 @@ RPM_GNUC_INTERNAL
 extern struct rpmdbOps_s ndb_dbops;
 #endif
 
+#if defined(WITH_LMDB)
+RPM_GNUC_INTERNAL
+extern struct rpmdbOps_s lmdb_dbops;
+#endif
+
 #ifdef __cplusplus
 }
 #endif