- Issue #4587: Add configure option --with-dbmliborder=db1:db2:... to specify

  the order that backends for the dbm extension are checked.

Misc/NEWS

@@ -880,6 +880,9 @@ Tools/Demos
 Build
 -----
 
+- Issue #4587: Add configure option --with-dbmliborder=db1:db2:... to specify
+  the order that backends for the dbm extension are checked. 
+
 - Link the shared python library with $(MODLIBS).
 
 - Issue #5134: Silence compiler warnings when compiling sqlite with VC++.

configure

 #! /bin/sh
-# From configure.in Revision: 71723 .
+# From configure.in Revision: 71731 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.61 for python 3.1.
 #
@@ -1340,6 +1340,10 @@ Optional Packages:
   --with-pydebug          build with Py_DEBUG defined
   --with-libs='lib1 ...'  link against additional libs
   --with-system-ffi       build _ctypes module using an installed ffi library
+  --with-dbmliborder=db1:db2:...
+                          order to check db backends for dbm. Valid value is a
+                          colon separated string with the backend names
+                          `ndbm', `gdbm' and `bdb'.
   --with-signal-module    disable/enable signal module
   --with-dec-threads      use DEC Alpha/OSF1 thread-safe libraries
   --with(out)-threads[=DIRECTORY]
@@ -14087,6 +14091,33 @@ fi
 { echo "$as_me:$LINENO: result: $with_system_ffi" >&5
 echo "${ECHO_T}$with_system_ffi" >&6; }
 
+# Check for --with-dbmliborder
+{ echo "$as_me:$LINENO: checking for --with-dbmliborder" >&5
+echo $ECHO_N "checking for --with-dbmliborder... $ECHO_C" >&6; }
+
+# Check whether --with-dbmliborder was given.
+if test "${with_dbmliborder+set}" = set; then
+  withval=$with_dbmliborder;
+if test x$with_dbmliborder = xyes
+then
+{ { echo "$as_me:$LINENO: error: proper usage is --with-dbmliborder=db1:db2:..." >&5
+echo "$as_me: error: proper usage is --with-dbmliborder=db1:db2:..." >&2;}
+   { (exit 1); exit 1; }; }
+else
+  for db in `echo $with_dbmliborder | sed 's/:/ /g'`; do
+    if test x$db != xndbm && test x$db != xgdbm && test x$db != xbdb
+    then
+      { { echo "$as_me:$LINENO: error: proper usage is --with-dbmliborder=db1:db2:..." >&5
+echo "$as_me: error: proper usage is --with-dbmliborder=db1:db2:..." >&2;}
+   { (exit 1); exit 1; }; }
+    fi
+  done
+fi
+fi
+
+{ echo "$as_me:$LINENO: result: $with_dbmliborder" >&5
+echo "${ECHO_T}$with_dbmliborder" >&6; }
+
 # Determine if signalmodule should be used.
 
 

configure.in

@@ -1837,6 +1837,24 @@ AC_ARG_WITH(system_ffi,
 
 AC_MSG_RESULT($with_system_ffi)
 
+# Check for --with-dbmliborder
+AC_MSG_CHECKING(for --with-dbmliborder)
+AC_ARG_WITH(dbmliborder,
+            AC_HELP_STRING([--with-dbmliborder=db1:db2:...], [order to check db backends for dbm. Valid value is a colon separated string with the backend names `ndbm', `gdbm' and `bdb'.]),
+[
+if test x$with_dbmliborder = xyes
+then
+AC_MSG_ERROR([proper usage is --with-dbmliborder=db1:db2:...])
+else
+  for db in `echo $with_dbmliborder | sed 's/:/ /g'`; do
+    if test x$db != xndbm && test x$db != xgdbm && test x$db != xbdb
+    then
+      AC_MSG_ERROR([proper usage is --with-dbmliborder=db1:db2:...])
+    fi
+  done
+fi])
+AC_MSG_RESULT($with_dbmliborder)
+
 # Determine if signalmodule should be used.
 AC_SUBST(USE_SIGNAL_MODULE)
 AC_SUBST(SIGNAL_OBJS)

setup.py

@@ -913,37 +913,69 @@ class PyBuildExt(build_ext):
 
         # The standard Unix dbm module:
         if platform not in ['cygwin']:
-            if find_file("ndbm.h", inc_dirs, []) is not None:
-                # Some systems have -lndbm, others don't
-                if self.compiler.find_library_file(lib_dirs, 'ndbm'):
-                    ndbm_libs = ['ndbm']
-                else:
-                    ndbm_libs = []
-                exts.append( Extension('_dbm', ['_dbmmodule.c'],
-                                       define_macros=[('HAVE_NDBM_H',None)],
-                                       libraries = ndbm_libs ) )
-            elif self.compiler.find_library_file(lib_dirs, 'gdbm'):
-                gdbm_libs = ['gdbm']
-                if self.compiler.find_library_file(lib_dirs, 'gdbm_compat'):
-                    gdbm_libs.append('gdbm_compat')
-                if find_file("gdbm/ndbm.h", inc_dirs, []) is not None:
-                    exts.append( Extension(
-                        '_dbm', ['_dbmmodule.c'],
-                        define_macros=[('HAVE_GDBM_NDBM_H',None)],
-                        libraries = gdbm_libs ) )
-                elif find_file("gdbm-ndbm.h", inc_dirs, []) is not None:
-                    exts.append( Extension(
-                        '_dbm', ['_dbmmodule.c'],
-                        define_macros=[('HAVE_GDBM_DASH_NDBM_H',None)],
-                        libraries = gdbm_libs ) )
-            elif db_incs is not None:
-                exts.append( Extension('_dbm', ['_dbmmodule.c'],
-                                       library_dirs=dblib_dir,
-                                       runtime_library_dirs=dblib_dir,
-                                       include_dirs=db_incs,
-                                       define_macros=[('HAVE_BERKDB_H',None),
-                                                      ('DB_DBM_HSEARCH',None)],
-                                       libraries=dblibs))
+            config_args = [arg.strip("'")
+                           for arg in sysconfig.get_config_var("CONFIG_ARGS").split()]
+            dbm_args = [arg.split('=')[-1] for arg in config_args
+                        if arg.startswith('--with-dbmliborder=')]
+            if dbm_args:
+                dbm_order = dbm_args[-1].split(":")
+            else:
+                dbm_order = "ndbm:gdbm:bdb".split(":")
+            dbmext = None
+            for cand in dbm_order:
+                if cand == "ndbm":
+                    if find_file("ndbm.h", inc_dirs, []) is not None:
+                        # Some systems have -lndbm, others don't
+                        if self.compiler.find_library_file(lib_dirs, 'ndbm'):
+                            ndbm_libs = ['ndbm']
+                        else:
+                            ndbm_libs = []
+                        print("building dbm using ndbm")
+                        dbmext = Extension('_dbm', ['_dbmmodule.c'],
+                                           define_macros=[
+                                               ('HAVE_NDBM_H',None),
+                                               ],
+                                           libraries=ndbm_libs)
+                        break
+
+                elif cand == "gdbm":
+                    if self.compiler.find_library_file(lib_dirs, 'gdbm'):
+                        gdbm_libs = ['gdbm']
+                        if self.compiler.find_library_file(lib_dirs, 'gdbm_compat'):
+                            gdbm_libs.append('gdbm_compat')
+                        if find_file("gdbm/ndbm.h", inc_dirs, []) is not None:
+                            print("building dbm using gdbm")
+                            dbmext = Extension(
+                                '_dbm', ['_dbmmodule.c'],
+                                define_macros=[
+                                    ('HAVE_GDBM_NDBM_H', None),
+                                    ],
+                                libraries = gdbm_libs)
+                            break
+                        if find_file("gdbm-ndbm.h", inc_dirs, []) is not None:
+                            print("building dbm using gdbm")
+                            dbmext = Extension(
+                                '_dbm', ['_dbmmodule.c'],
+                                define_macros=[
+                                    ('HAVE_GDBM_DASH_NDBM_H', None),
+                                    ],
+                                libraries = gdbm_libs)
+                            break
+                elif cand == "bdb":
+                    if db_incs is not None:
+                        print("building dbm using bdb")
+                        dbmext = Extension('_dbm', ['_dbmmodule.c'],
+                                           library_dirs=dblib_dir,
+                                           runtime_library_dirs=dblib_dir,
+                                           include_dirs=db_incs,
+                                           define_macros=[
+                                               ('HAVE_BERKDB_H', None),
+                                               ('DB_DBM_HSEARCH', None),
+                                               ],
+                                           libraries=dblibs)
+                        break
+            if dbmext is not None:
+                exts.append(dbmext)
             else:
                 missing.append('_dbm')