Move PRDR out of EXPERIMENTAL

13 files changed, 91 insertions, 90 deletions

diff --git a/src/src/EDITME b/src/src/EDITME
index d13b1b13a..7d58af744 100644
--- a/src/src/EDITME
+++ b/src/src/EDITME
@@ -410,6 +410,10 @@ EXIM_MONITOR=eximon.bin
 
 # DISABLE_DKIM=yes
 
+#------------------------------------------------------------------------------
+# Uncomment the following line to remove Per-Recipient-Data-Response support.
+
+# DISABLE_PRDR=yes
 
 #------------------------------------------------------------------------------
 # By default, Exim has support for checking the AD bit in a DNS response, to
@@ -466,8 +470,6 @@ EXIM_MONITOR=eximon.bin
 # CFLAGS += -I/usr/local/include
 # LDFLAGS += -lopendmarc
 
-# Uncomment the following line to add Per-Recipient-Data-Response support.
-# EXPERIMENTAL_PRDR=yes
 
 # Uncomment the following line to support Transport post-delivery actions,
 # eg. for logging to a database.
diff --git a/src/src/acl.c b/src/src/acl.c
index 42b9091c3..e8a0657f2 100644
--- a/src/src/acl.c
+++ b/src/src/acl.c
@@ -397,7 +397,7 @@ static unsigned int cond_forbids[] = {
   (unsigned int)
   ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|       /* add_header */
     (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
   #endif
     (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
@@ -412,7 +412,7 @@ static unsigned int cond_forbids[] = {
   (1<<ACL_WHERE_AUTH)|                             /* bmi_optin */
     (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
     (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
   #endif
     (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
@@ -434,9 +434,9 @@ static unsigned int cond_forbids[] = {
   #ifdef EXPERIMENTAL_DCC
   (unsigned int)
   ~((1<<ACL_WHERE_DATA)|                           /* dcc */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_NOTSMTP)),
   #endif
 
@@ -450,9 +450,9 @@ static unsigned int cond_forbids[] = {
   #ifdef WITH_OLD_DEMIME
   (unsigned int)
   ~((1<<ACL_WHERE_DATA)|                           /* demime */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_NOTSMTP)),
   #endif
 
@@ -474,7 +474,7 @@ static unsigned int cond_forbids[] = {
 
   (unsigned int)
   ~((1<<ACL_WHERE_RCPT)                            /* domains */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     |(1<<ACL_WHERE_PRDR)
   #endif
     ),
@@ -505,9 +505,9 @@ static unsigned int cond_forbids[] = {
   #ifdef WITH_CONTENT_SCAN
   (unsigned int)
   ~((1<<ACL_WHERE_DATA)|                           /* malware */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_NOTSMTP)),
   #endif
 
@@ -526,9 +526,9 @@ static unsigned int cond_forbids[] = {
   #ifdef WITH_CONTENT_SCAN
   (unsigned int)
   ~((1<<ACL_WHERE_DATA)|                           /* regex */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_NOTSMTP)|
     (1<<ACL_WHERE_MIME)),
   #endif
@@ -536,7 +536,7 @@ static unsigned int cond_forbids[] = {
   (unsigned int)
   ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|       /* remove_header */
     (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
   #endif
     (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
@@ -559,9 +559,9 @@ static unsigned int cond_forbids[] = {
   #ifdef WITH_CONTENT_SCAN
   (unsigned int)
   ~((1<<ACL_WHERE_DATA)|                           /* spam */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_NOTSMTP)),
   #endif
 
@@ -608,9 +608,9 @@ static unsigned int control_forbids[] = {
 
   #ifndef DISABLE_DKIM
   (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)|      /* dkim_disable_verify */
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_NOTSMTP_START),
   #endif
 
@@ -674,17 +674,17 @@ static unsigned int control_forbids[] = {
   (unsigned int)
   ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|       /* fakedefer */
     (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_MIME)),
 
   (unsigned int)
   ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|       /* fakereject */
     (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
     (1<<ACL_WHERE_PRDR)|
-  #endif /* EXPERIMENTAL_PRDR */
+  #endif
     (1<<ACL_WHERE_MIME)),
 
   (1<<ACL_WHERE_NOTSMTP)|                          /* no_multiline */
@@ -4319,7 +4319,7 @@ sender_verified_failed = NULL;
 ratelimiters_cmd = NULL;
 log_reject_target = LOG_MAIN|LOG_REJECT;
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR )
 #else
 if (where == ACL_WHERE_RCPT )
@@ -4363,7 +4363,7 @@ If conn-failure, no action (and keep the spooled copy).
 switch (where)
 {
 case ACL_WHERE_RCPT:
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 case ACL_WHERE_PRDR:
 #endif
   if( rcpt_count > 1 )
diff --git a/src/src/deliver.c b/src/src/deliver.c
index 777ff8dc7..6bdfbd4da 100644
--- a/src/src/deliver.c
+++ b/src/src/deliver.c
@@ -830,7 +830,7 @@ else
       }
     }
 
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
   if (addr->flags & af_prdr_used)
     s = string_append(s, &size, &ptr, 1, US" PRDR");
   #endif
@@ -3043,9 +3043,10 @@ while (!done)
     while (*ptr++);
     break;
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
     case 'P':
-    addr->flags |= af_prdr_used; break;
+    addr->flags |= af_prdr_used;
+    break;
 #endif
 
     case 'A':
@@ -6280,7 +6281,7 @@ if (addr_remote != NULL)
     regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
   #endif
 
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
   if (regex_PRDR == NULL) regex_PRDR =
     regex_must_compile(US"\\n250[\\s\\-]PRDR(\\s|\\n|$)", FALSE, TRUE);
   #endif
diff --git a/src/src/exim.c b/src/src/exim.c
index fa0cf4940..ded12fa34 100644
--- a/src/src/exim.c
+++ b/src/src/exim.c
@@ -822,9 +822,6 @@ fprintf(f, "Support for:");
 #ifdef EXPERIMENTAL_OCSP
   fprintf(f, " Experimental_OCSP");
 #endif
-#ifdef EXPERIMENTAL_PRDR
-  fprintf(f, " Experimental_PRDR");
-#endif
 #ifdef EXPERIMENTAL_PROXY
   fprintf(f, " Experimental_Proxy");
 #endif
diff --git a/src/src/globals.c b/src/src/globals.c
index a2cc50313..a25b06a05 100644
--- a/src/src/globals.c
+++ b/src/src/globals.c
@@ -155,7 +155,7 @@ uschar *tls_verify_certificates= NULL;
 uschar *tls_verify_hosts       = NULL;
 #endif
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 /* Per Recipient Data Response variables */
 BOOL    prdr_enable            = FALSE;
 BOOL    prdr_requested         = FALSE;
@@ -218,7 +218,7 @@ uschar *acl_removed_headers    = NULL;
 uschar *acl_smtp_auth          = NULL;
 uschar *acl_smtp_connect       = NULL;
 uschar *acl_smtp_data          = NULL;
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 uschar *acl_smtp_data_prdr     = NULL;
 #endif
 #ifndef DISABLE_DKIM
@@ -254,7 +254,7 @@ uschar *acl_wherenames[]       = { US"RCPT",
                                    US"MIME",
                                    US"DKIM",
                                    US"DATA",
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
                                    US"PRDR",
 #endif
                                    US"non-SMTP",
@@ -279,7 +279,7 @@ uschar *acl_wherecodes[]       = { US"550",     /* RCPT */
                                    US"550",     /* MIME */
                                    US"550",     /* DKIM */
                                    US"550",     /* DATA */
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
                                    US"550",    /* RCPT PRDR */
 #endif
                                    US"0",       /* not SMTP; not relevant */
diff --git a/src/src/globals.h b/src/src/globals.h
index 8b55321f9..3d4cd3981 100644
--- a/src/src/globals.h
+++ b/src/src/globals.h
@@ -160,7 +160,7 @@ extern uschar *acl_removed_headers;    /* Headers deleted by an ACL */
 extern uschar *acl_smtp_auth;          /* ACL run for AUTH */
 extern uschar *acl_smtp_connect;       /* ACL run on SMTP connection */
 extern uschar *acl_smtp_data;          /* ACL run after DATA received */
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 extern uschar *acl_smtp_data_prdr;     /* ACL run after DATA received if in PRDR mode*/
 const extern pcre *regex_PRDR;         /* For recognizing PRDR settings */
 #endif
@@ -592,7 +592,7 @@ extern uschar *percent_hack_domains;   /* Local domains for which '% operates */
 extern uschar *pid_file_path;          /* For writing daemon pids */
 extern uschar *pipelining_advertise_hosts; /* As it says */
 extern BOOL    pipelining_enable;      /* As it says */
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 extern BOOL    prdr_enable;            /* As it says */
 extern BOOL    prdr_requested;         /* Connecting mail server wants PRDR */
 #endif
diff --git a/src/src/macros.h b/src/src/macros.h
index fc3776c84..53c0e3e27 100644
--- a/src/src/macros.h
+++ b/src/src/macros.h
@@ -826,7 +826,7 @@ enum { ACL_WHERE_RCPT,       /* Some controls are for RCPT only */
        ACL_WHERE_MIME,       /* ) implemented by <= WHERE_NOTSMTP           */
        ACL_WHERE_DKIM,       /* )                                           */
        ACL_WHERE_DATA,       /* )                                           */
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
        ACL_WHERE_PRDR,       /* )                                           */
 #endif
        ACL_WHERE_NOTSMTP,    /* )                                           */
diff --git a/src/src/readconf.c b/src/src/readconf.c
index f213b2c57..db1d766b0 100644
--- a/src/src/readconf.c
+++ b/src/src/readconf.c
@@ -140,7 +140,7 @@ static optionlist optionlist_config[] = {
   { "acl_smtp_auth",            opt_stringptr,   &acl_smtp_auth },
   { "acl_smtp_connect",         opt_stringptr,   &acl_smtp_connect },
   { "acl_smtp_data",            opt_stringptr,   &acl_smtp_data },
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   { "acl_smtp_data_prdr",       opt_stringptr,   &acl_smtp_data_prdr },
 #endif
 #ifndef DISABLE_DKIM
@@ -324,7 +324,7 @@ static optionlist optionlist_config[] = {
 #endif
   { "pid_file_path",            opt_stringptr,   &pid_file_path },
   { "pipelining_advertise_hosts", opt_stringptr, &pipelining_advertise_hosts },
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   { "prdr_enable",              opt_bool,        &prdr_enable },
 #endif
   { "preserve_message_logs",    opt_bool,        &preserve_message_logs },
diff --git a/src/src/receive.c b/src/src/receive.c
index 407af58f8..af8e6de4c 100644
--- a/src/src/receive.c
+++ b/src/src/receive.c
@@ -519,7 +519,7 @@ Arguments:
 Returns:       nothing
 */
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 static void
 smtp_user_msg(uschar *code, uschar *user_msg)
 {
@@ -3276,8 +3276,8 @@ else
     dmarc_up = dmarc_store_data(from_header);
 #endif /* EXPERIMENTAL_DMARC */
 
-#ifdef EXPERIMENTAL_PRDR
-    if (prdr_requested && recipients_count > 1 && acl_smtp_data_prdr != NULL )
+#ifndef DISABLE_PRDR
+    if (prdr_requested && recipients_count > 1 && acl_smtp_data_prdr)
       {
       unsigned int c;
       int all_pass = OK;
@@ -3345,7 +3345,7 @@ else
       }
     else
       prdr_requested = FALSE;
-#endif /* EXPERIMENTAL_PRDR */
+#endif /* !DISABLE_PRDR */
 
     /* Check the recipients count again, as the MIME ACL might have changed
     them. */
@@ -3738,21 +3738,20 @@ if (message_reference != NULL)
 s = add_host_info_for_log(s, &size, &sptr);
 
 #ifdef SUPPORT_TLS
-if ((log_extra_selector & LX_tls_cipher) != 0 && tls_in.cipher != NULL)
+if (log_extra_selector & LX_tls_cipher && tls_in.cipher)
   s = string_append(s, &size, &sptr, 2, US" X=", tls_in.cipher);
-if ((log_extra_selector & LX_tls_certificate_verified) != 0 &&
-     tls_in.cipher != NULL)
+if (log_extra_selector & LX_tls_certificate_verified && tls_in.cipher)
   s = string_append(s, &size, &sptr, 2, US" CV=",
     tls_in.certificate_verified? "yes":"no");
-if ((log_extra_selector & LX_tls_peerdn) != 0 && tls_in.peerdn != NULL)
+if (log_extra_selector & LX_tls_peerdn && tls_in.peerdn)
   s = string_append(s, &size, &sptr, 3, US" DN=\"",
     string_printing(tls_in.peerdn), US"\"");
-if ((log_extra_selector & LX_tls_sni) != 0 && tls_in.sni != NULL)
+if (log_extra_selector & LX_tls_sni && tls_in.sni)
   s = string_append(s, &size, &sptr, 3, US" SNI=\"",
     string_printing(tls_in.sni), US"\"");
 #endif
 
-if (sender_host_authenticated != NULL)
+if (sender_host_authenticated)
   {
   s = string_append(s, &size, &sptr, 2, US" A=", sender_host_authenticated);
   if (authenticated_id != NULL)
@@ -3763,16 +3762,14 @@ if (sender_host_authenticated != NULL)
     }
   }
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 if (prdr_requested)
   s = string_append(s, &size, &sptr, 1, US" PRDR");
 #endif
+
 #ifdef EXPERIMENTAL_PROXY
-if (proxy_session &&
-    (log_extra_selector & LX_proxy) != 0)
-  {
+if (proxy_session &&  log_extra_selector & LX_proxy)
   s = string_append(s, &size, &sptr, 2, US" PRX=", proxy_host_address);
-  }
 #endif
 
 sprintf(CS big_buffer, "%d", msg_size);
@@ -3990,11 +3987,11 @@ if(cutthrough_fd >= 0)
     }
   }
 
-if(smtp_reply == NULL
-#ifdef EXPERIMENTAL_PRDR
-                     || prdr_requested
+#ifndef DISABLE_PRDR
+if(!smtp_reply || prdr_requested)
+#else
+if(!smtp_reply)
 #endif
-  )
   {
   log_write(0, LOG_MAIN |
     (((log_extra_selector & LX_received_recipients) != 0)? LOG_RECIPIENTS : 0) |
diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c
index 82a805a21..aad778eef 100644
--- a/src/src/smtp_in.c
+++ b/src/src/smtp_in.c
@@ -214,7 +214,7 @@ static uschar *protocols[] = {
 /* Sanity check and validate optional args to MAIL FROM: envelope */
 enum {
   ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH,
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   ENV_MAIL_OPT_PRDR,
 #endif
   ENV_MAIL_OPT_NULL
@@ -229,7 +229,7 @@ static env_mail_type_t env_mail_type_list[] = {
     { US"SIZE",   ENV_MAIL_OPT_SIZE,   TRUE  },
     { US"BODY",   ENV_MAIL_OPT_BODY,   TRUE  },
     { US"AUTH",   ENV_MAIL_OPT_AUTH,   TRUE  },
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
     { US"PRDR",   ENV_MAIL_OPT_PRDR,   FALSE },
 #endif
     { US"NULL",   ENV_MAIL_OPT_NULL,   FALSE }
@@ -2637,7 +2637,7 @@ uschar *what =
 #endif
   (where == ACL_WHERE_PREDATA)? US"DATA" :
   (where == ACL_WHERE_DATA)? US"after DATA" :
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   (where == ACL_WHERE_PRDR)? US"after DATA PRDR" :
 #endif
   (smtp_cmd_data == NULL)?
@@ -3628,12 +3628,13 @@ while (done <= 0)
         }
       #endif
 
-      #ifdef EXPERIMENTAL_PRDR
+      #ifndef DISABLE_PRDR
       /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */
-      if (prdr_enable) {
+      if (prdr_enable)
+        {
         s = string_cat(s, &size, &ptr, smtp_code, 3);
         s = string_cat(s, &size, &ptr, US"-PRDR\r\n", 7);
-      }
+	}
       #endif
 
       /* Finish off the multiline reply with one that is always available. */
@@ -3862,9 +3863,9 @@ while (done <= 0)
             }
             break;
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
         case ENV_MAIL_OPT_PRDR:
-          if ( prdr_enable )
+          if (prdr_enable)
             prdr_requested = TRUE;
           break;
 #endif
@@ -3989,29 +3990,32 @@ while (done <= 0)
     when pipelining is not advertised, do another sync check in case the ACL
     delayed and the client started sending in the meantime. */
 
-    if (acl_smtp_mail == NULL) rc = OK; else
+    if (acl_smtp_mail)
       {
       rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg);
       if (rc == OK && !pipelining_advertised && !check_sync())
         goto SYNC_FAILURE;
       }
+    else
+      rc = OK;
 
     if (rc == OK || rc == DISCARD)
       {
-      if (user_msg == NULL) 
+      if (!user_msg)
         smtp_printf("%s%s%s", US"250 OK",
-                  #ifdef EXPERIMENTAL_PRDR
-                    prdr_requested == TRUE ? US", PRDR Requested" :
-                  #endif
+                  #ifndef DISABLE_PRDR
+                    prdr_requested ? US", PRDR Requested" : US"",
+		  #else
                     US"",
+                  #endif
                     US"\r\n");
       else 
         {
-      #ifdef EXPERIMENTAL_PRDR
-        if ( prdr_requested == TRUE )
+      #ifndef DISABLE_PRDR
+        if (prdr_requested)
            user_msg = string_sprintf("%s%s", user_msg, US", PRDR Requested");
       #endif
-        smtp_user_msg(US"250",user_msg);
+        smtp_user_msg(US"250", user_msg);
         }
       smtp_delay_rcpt = smtp_rlr_base;
       recipients_discarded = (rc == DISCARD);
diff --git a/src/src/structs.h b/src/src/structs.h
index 989653e30..a9edb4670 100644
--- a/src/src/structs.h
+++ b/src/src/structs.h
@@ -488,7 +488,7 @@ typedef struct address_item_propagated {
 #define af_cert_verified       0x01000000 /* delivered with verified TLS cert */
 #define af_pass_message        0x02000000 /* pass message in bounces */
 #define af_bad_reply           0x04000000 /* filter could not generate autoreply */
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 # define af_prdr_used          0x08000000 /* delivery used SMTP PRDR */
 #endif
 #define af_force_command       0x10000000 /* force_command in pipe transport */
diff --git a/src/src/transports/smtp.c b/src/src/transports/smtp.c
index 020f76cac..71a9f2376 100644
--- a/src/src/transports/smtp.c
+++ b/src/src/transports/smtp.c
@@ -118,7 +118,7 @@ optionlist smtp_transport_options[] = {
 #endif
   { "hosts_try_auth",       opt_stringptr,
       (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   { "hosts_try_prdr",       opt_stringptr,
       (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
 #endif
@@ -196,7 +196,7 @@ smtp_transport_options_block smtp_transport_option_defaults = {
   NULL,                /* serialize_hosts */
   NULL,                /* hosts_try_auth */
   NULL,                /* hosts_require_auth */
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   NULL,                /* hosts_try_prdr */
 #endif
 #ifdef EXPERIMENTAL_OCSP
@@ -1185,7 +1185,7 @@ BOOL completed_address = FALSE;
 BOOL esmtp = TRUE;
 BOOL pending_MAIL;
 BOOL pass_message = FALSE;
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 BOOL prdr_offered = FALSE;
 BOOL prdr_active;
 #endif
@@ -1386,7 +1386,7 @@ goto SEND_QUIT;
       PCRE_EOPT, NULL, 0) >= 0;
   #endif
 
-  #ifdef EXPERIMENTAL_PRDR
+  #ifndef DISABLE_PRDR
   prdr_offered = esmtp &&
     (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
       PCRE_EOPT, NULL, 0) >= 0) &&
@@ -1585,7 +1585,7 @@ if (continue_hostname == NULL
   DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
     smtp_use_pipelining? "" : "not ");
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   prdr_offered = esmtp &&
     pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
       PCRE_EOPT, NULL, 0) >= 0 &&
@@ -1673,7 +1673,7 @@ if (smtp_use_size)
   while (*p) p++;
   }
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 prdr_active = FALSE;
 if (prdr_offered)
   {
@@ -1909,7 +1909,7 @@ if (!ok) ok = TRUE; else
 
   smtp_command = US"end of data";
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   /* For PRDR we optionally get a partial-responses warning
    * followed by the individual responses, before going on with
    * the overall response.  If we don't get the warning then deal
@@ -2004,7 +2004,7 @@ if (!ok) ok = TRUE; else
       address. For temporary errors, add a retry item for the address so that
       it doesn't get tried again too soon. */
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
       if (lmtp || prdr_active)
 #else
       if (lmtp)
@@ -2015,7 +2015,7 @@ if (!ok) ok = TRUE; else
           {
           if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
           addr->message = string_sprintf(
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
 	    "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
 #else
 	    "LMTP error after %s: %s",
@@ -2029,7 +2029,7 @@ if (!ok) ok = TRUE; else
             errno = ERRNO_DATA4XX;
             addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
             addr->transport_return = DEFER;
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
             if (!prdr_active)
 #endif
               retry_add_item(addr, addr->address_retry_key, 0);
@@ -2052,12 +2052,12 @@ if (!ok) ok = TRUE; else
       addr->host_used = thost;
       addr->special_action = flag;
       addr->message = conf;
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
       if (prdr_active) addr->flags |= af_prdr_used;
 #endif
       flag = '-';
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
       if (!prdr_active)
 #endif
         {
@@ -2079,7 +2079,7 @@ if (!ok) ok = TRUE; else
         }
       }
 
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
       if (prdr_active)
         {
 	/* PRDR - get the final, overall response.  For any non-success
diff --git a/src/src/transports/smtp.h b/src/src/transports/smtp.h
index 900542564..c7de0091a 100644
--- a/src/src/transports/smtp.h
+++ b/src/src/transports/smtp.h
@@ -21,7 +21,7 @@ typedef struct {
   uschar *serialize_hosts;
   uschar *hosts_try_auth;
   uschar *hosts_require_auth;
-#ifdef EXPERIMENTAL_PRDR
+#ifndef DISABLE_PRDR
   uschar *hosts_try_prdr;
 #endif
 #ifdef EXPERIMENTAL_OCSP