From ebf59d1a28b49b391b8025d7017bacf853c01aa2 Mon Sep 17 00:00:00 2001
From: Lars Ingebrigtsen <larsi@gnus.org>
Date: Sat, 11 Dec 2021 06:40:01 +0100
Subject: [PATCH] Check whether the sqlite supports sqlite3_load_extension

* configure.ac: Check for sqlite3_load_extension, which is
apparently missing in some versions.
* src/sqlite.c: Add guards.
(Fsqlite_load_extension): Ifdef out on systems that doesn't have it.
---
 configure.ac |  5 +++++
 src/sqlite.c | 17 +++++++++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/configure.ac b/configure.ac
index 5eb23849b53..8d15c70d847 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2695,6 +2695,11 @@ if test "${with_sqlite3}" != "no"; then
      if test "${opsys}" = "mingw32"; then
         SQLITE3_LIBS=
      fi
+     AC_CHECK_LIB(sqlite3, sqlite3_load_extension,
+         HAVE_SQLITE3_LOAD_EXTENSION=yes, HAVE_SQLITE3_LOAD_EXTENSION=no)
+     if test "$HAVE_SQLITE3_LOAD_EXTENSION" = "yes"; then
+       AC_DEFINE(HAVE_SQLITE3_LOAD_EXTENSION, 1, [Define to 1 if sqlite3 supports loading extensions.])
+     fi
    fi
 fi
 
diff --git a/src/sqlite.c b/src/sqlite.c
index 50989434ffa..42a7a3a0268 100644
--- a/src/sqlite.c
+++ b/src/sqlite.c
@@ -65,11 +65,16 @@ DEF_DLL_FN (SQLITE_API const char*, sqlite3_column_name, (sqlite3_stmt*, int));
 DEF_DLL_FN (SQLITE_API int, sqlite3_exec,
 	    (sqlite3*, const char*, int (*callback)(void*,int,char**,char**),
 	     void*, char**));
-DEF_DLL_FN (SQLITE_API int, sqlite3_load_extension,
-	    (sqlite3*, const char*, const char*, char**));
 DEF_DLL_FN (SQLITE_API int, sqlite3_prepare_v2,
 	    (sqlite3*, const char*, int, sqlite3_stmt**, const char**));
 
+# ifdef HAVE_SQLITE3_LOAD_EXTENSION
+DEF_DLL_FN (SQLITE_API int, sqlite3_load_extension,
+	    (sqlite3*, const char*, const char*, char**));
+#  undef sqlite3_load_extension
+#  define sqlite3_load_extension fn_sqlite3_load_extension
+# endif
+
 # undef sqlite3_finalize
 # undef sqlite3_close
 # undef sqlite3_open_v2
@@ -91,7 +96,6 @@ DEF_DLL_FN (SQLITE_API int, sqlite3_prepare_v2,
 # undef sqlite3_column_text
 # undef sqlite3_column_name
 # undef sqlite3_exec
-# undef sqlite3_load_extension
 # undef sqlite3_prepare_v2
 
 # define sqlite3_finalize fn_sqlite3_finalize
@@ -115,7 +119,6 @@ DEF_DLL_FN (SQLITE_API int, sqlite3_prepare_v2,
 # define sqlite3_column_text fn_sqlite3_column_text
 # define sqlite3_column_name fn_sqlite3_column_name
 # define sqlite3_exec fn_sqlite3_exec
-# define sqlite3_load_extension fn_sqlite3_load_extension
 # define sqlite3_prepare_v2 fn_sqlite3_prepare_v2
 
 static bool
@@ -142,7 +145,9 @@ load_dll_functions (HMODULE library)
   LOAD_DLL_FN (library, sqlite3_column_text);
   LOAD_DLL_FN (library, sqlite3_column_name);
   LOAD_DLL_FN (library, sqlite3_exec);
+# ifdef HAVE_SQLITE3_LOAD_EXTENSION
   LOAD_DLL_FN (library, sqlite3_load_extension);
+# endif
   LOAD_DLL_FN (library, sqlite3_prepare_v2);
   return true;
 }
@@ -576,6 +581,7 @@ DEFUN ("sqlite-rollback", Fsqlite_rollback, Ssqlite_rollback, 1, 1, 0,
   return sqlite_exec (XSQLITE (db)->db, "rollback");
 }
 
+#ifdef HAVE_SQLITE3_LOAD_EXTENSION
 DEFUN ("sqlite-load-extension", Fsqlite_load_extension,
        Ssqlite_load_extension, 2, 2, 0,
        doc: /* Load an SQlite module into DB.
@@ -593,6 +599,7 @@ MODULE should be the file name of an SQlite module .so file.  */)
     return Qt;
   return Qnil;
 }
+#endif /* HAVE_SQLITE3_LOAD_EXTENSION */
 
 DEFUN ("sqlite-next", Fsqlite_next, Ssqlite_next, 1, 1, 0,
        doc: /* Return the next result set from SET.  */)
@@ -691,7 +698,9 @@ syms_of_sqlite (void)
   defsubr (&Ssqlite_transaction);
   defsubr (&Ssqlite_commit);
   defsubr (&Ssqlite_rollback);
+#ifdef HAVE_SQLITE3_LOAD_EXTENSION
   defsubr (&Ssqlite_load_extension);
+#endif
   defsubr (&Ssqlite_next);
   defsubr (&Ssqlite_columns);
   defsubr (&Ssqlite_more_p);
-- 
2.39.5