bpo-45747: Detect gdbm/dbm dependencies in configure (GH-29467)

Co-authored-by: Erlend Egeberg Aasland <[email protected]>

Author: tiran

Doc/whatsnew/3.11.rst

@@ -528,6 +528,10 @@ Build Changes
   detected by :program:`configure`.
   (Contributed by Christian Heimes in :issue:`45763`.)
 
+* Build dependencies for :mod:`dbm` are now detected by :program:`configure`.
+  ``libdb`` 3.x and 4.x are no longer supported.
+  (Contributed by Christian Heimes in :issue:`45747`.)
+
 C API Changes
 =============
 

Misc/NEWS.d/next/Build/2021-11-08-11-31-48.bpo-45747.AODmk_.rst

@@ -0,0 +1 @@
+gdbm and dbm build dependencies are now detected by ``configure``.

Modules/Setup

@@ -216,7 +216,7 @@ time timemodule.c
 #_bz2 _bz2module.c -lbz2
 #_ctypes _ctypes/_ctypes.c _ctypes/callbacks.c _ctypes/callproc.c _ctypes/stgdict.c _ctypes/cfield.c -ldl -lffi -DHAVE_FFI_PREP_CIF_VAR -DHAVE_FFI_PREP_CLOSURE_LOC -DHAVE_FFI_CLOSURE_ALLOC
 # The _dbm module supports NDBM, GDBM with compat module, and Berkeley DB.
-#_dbm _dbmmodule.c -lgdbm_compat -DHAVE_NDBM_H
+#_dbm _dbmmodule.c -lgdbm_compat -DUSE_GDBM_COMPAT
 #_gdbm _gdbmmodule.c -lgdbm
 #_lzma _lzmamodule.c -llzma
 #_sqlite3 _sqlite/connection.c _sqlite/cursor.c _sqlite/microprotocols.c _sqlite/module.c _sqlite/prepare_protocol.c _sqlite/row.c _sqlite/statement.c _sqlite/util.c -lsqlite3

Modules/_dbmmodule.c

@@ -12,20 +12,26 @@
 /* Some Linux systems install gdbm/ndbm.h, but not ndbm.h.  This supports
  * whichever configure was able to locate.
  */
-#if defined(HAVE_NDBM_H)
-#include <ndbm.h>
-static const char which_dbm[] = "GNU gdbm";  /* EMX port of GDBM */
-#elif defined(HAVE_GDBM_NDBM_H)
-#include <gdbm/ndbm.h>
-static const char which_dbm[] = "GNU gdbm";
-#elif defined(HAVE_GDBM_DASH_NDBM_H)
-#include <gdbm-ndbm.h>
-static const char which_dbm[] = "GNU gdbm";
-#elif defined(HAVE_BERKDB_H)
-#include <db.h>
-static const char which_dbm[] = "Berkeley DB";
+#if defined(USE_NDBM)
+  #include <ndbm.h>
+  static const char which_dbm[] = "GNU gdbm";  /* EMX port of GDBM */
+#elif defined(USE_GDBM_COMPAT)
+  #ifdef HAVE_GDBM_NDBM_H
+    #include <gdbm/ndbm.h>
+  #elif HAVE_GDBM_DASH_NDBM_H
+    #include <gdbm-ndbm.h>
+  #else
+    #error "No gdbm/ndbm.h or gdbm-ndbm.h available"
+  #endif
+  static const char which_dbm[] = "GNU gdbm";
+#elif defined(USE_BERKDB)
+  #ifndef DB_DBM_HSEARCH
+    #define DB_DBM_HSEARCH 1
+  #endif
+  #include <db.h>
+  static const char which_dbm[] = "Berkeley DB";
 #else
-#error "No ndbm.h available!"
+  #error "No ndbm.h available!"
 #endif
 
 typedef struct {