Added a version number to the plugin ABI to prevent semantic mismatches.

NEWS

@@ -3,8 +3,8 @@ Changes in version 1.10
 
 - Added a ClamAV virus scanner plugin.
 
-- Modified the plugin API to add a flags word and to (optionally) save
-  messages to a temporary file (needed by the ClamAV plugin).
+- Modified the plugin API to add a version code, a flags word, and to
+  (optionally) save messages to a temporary file.
 
 Development of this version has been sponsored by FutureQuest, Inc.
 [email protected]  http://www.FutureQuest.net/

backend-echo.c

@@ -85,6 +85,7 @@ static const response* message_end(int fd)
 }
 
 struct plugin backend = {
+  .version = PLUGIN_VERSION,
   .reset = reset,
   .sender = sender,
   .recipient = recipient,

backend-qmail.c

@@ -204,6 +204,7 @@ static const response* message_end(int fd)
 }
 
 struct plugin backend = {
+  .version = PLUGIN_VERSION,
   .reset = reset,
   .sender = do_sender,
   .recipient = do_recipient,

mailfront.h

@@ -9,8 +9,11 @@
 
 #define FLAG_NEED_FILE (1<<0)
 
+#define PLUGIN_VERSION 2
+
 struct plugin
 {
+  unsigned version;
   struct plugin* next;
   const char* name;
   unsigned flags;
@@ -24,8 +27,11 @@ struct plugin
   const response* (*message_end)(int fd);
 };
 
+#define PROTOCOL_VERSION 2
+
 struct protocol
 {
+  unsigned version;
   const char* name;
   int (*respond_line)(unsigned number, int final,
 		      const char* msg, unsigned long len);

modules.c

@@ -6,6 +6,9 @@
 #include "conf_modules.c"
 
 static response resp_load = { 451, 0 };
+static RESPONSE(backend_version,451,"4.3.0 Backend ABI version mismatch");
+static RESPONSE(plugin_version,451,"4.3.0 Plugin ABI version mismatch");
+static RESPONSE(protocol_version,451,"4.3.0 Protocol ABI version mismatch");
 
 struct plugin* plugin_list = 0;
 struct plugin* plugin_tail = 0;
@@ -97,6 +100,8 @@ static const response* load_plugin(const char* name)
     if ((plugin = find_builtin_plugin(name)) == 0) {
       if ((plugin = load_object("plugin", name)) == 0)
 	return &resp_load;
+      if (plugin->version != PLUGIN_VERSION)
+	return &resp_plugin_version;
       if ((plugin->name = strdup(name)) == 0)
 	return &resp_oom;
     }
@@ -140,8 +145,12 @@ const response* load_modules(const char* protocol_name,
     module_path = conf_modules;
   if ((session.protocol = load_object("protocol", protocol_name)) == 0)
     return &resp_load;
+  if (session.protocol->version != PROTOCOL_VERSION)
+    return &resp_protocol_version;
   if ((session.backend = load_object("backend", backend_name)) == 0)
     return &resp_load;
+  if (session.backend->version != PLUGIN_VERSION)
+    return &resp_backend_version;
   module_flags |= session.backend->flags;
   while (*plugins != 0)
     if ((r = load_plugins(*plugins++)) != 0)

plugin-add-received.c

@@ -144,6 +144,7 @@ static const response* data_start(int fd)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .init = init,
   .data_start = data_start,
 };

plugin-check-fqdn.c

@@ -17,6 +17,7 @@ static const response* either(str* s)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .sender = either,
   .recipient = either,
 };

plugin-clamav.c

@@ -102,6 +102,7 @@ static const response* message_end(int fd)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .flags = FLAG_NEED_FILE,
   .message_end = message_end,
 };

plugin-counters.c

@@ -126,6 +126,7 @@ static const response* block(const char* bytes, unsigned long len)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .init = init,
   .reset = reset,
   .sender = sender,

plugin-cvm-validate.c

@@ -53,6 +53,7 @@ static const response* validate_recipient(str* recipient)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .init = validate_init,
   .recipient = validate_recipient,
 };

plugin-mailrules.c

@@ -426,6 +426,7 @@ static const response* validate_recipient(str* recipient)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .init = init,
   .reset = reset,
   .sender = validate_sender,

plugin-patterns.c

@@ -149,6 +149,7 @@ static const response* check(const char* bytes, unsigned long len)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .data_start = init,
   .data_block = check,
 };

plugin-qmail-validate.c

@@ -87,6 +87,7 @@ static const response* validate_recipient(str* recipient)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .init = validate_init,
   .sender = validate_sender,
   .recipient = validate_recipient,

plugin-reject.c

@@ -24,5 +24,6 @@ static const response* sender(str* s)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .sender = sender,
 };

plugin-relayclient.c

@@ -16,5 +16,6 @@ static const response* do_recipient(str* recipient)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .recipient = do_recipient,
 };

plugin-require-auth.c

@@ -12,5 +12,6 @@ static const response* sender(str* s)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .sender = sender,
 };

plugin.c

@@ -40,6 +40,7 @@ static const response* message_end(int fd)
 }
 
 struct plugin plugin = {
+  .version = PLUGIN_VERSION,
   .flags = 0,
   .init = init,
   .helo = helo,

protocol-qmqp.c

@@ -103,6 +103,7 @@ static int mainloop(void)
 }
 
 struct protocol protocol = {
+  .version = PROTOCOL_VERSION,
   .name = "QMQP",
   .respond_line = qmtp_respond_line,
   .mainloop = mainloop,

protocol-qmtp.c

@@ -108,6 +108,7 @@ static int mainloop(void)
 }
 
 struct protocol protocol = {
+  .version = PROTOCOL_VERSION,
   .name = "QMTP",
   .respond_line = qmtp_respond_line,
   .mainloop = mainloop,

protocol-smtp.c

@@ -407,6 +407,7 @@ static int smtp_respond_line(unsigned num, int final,
 }
 
 struct protocol protocol = {
+  .version = PROTOCOL_VERSION,
   .name = "SMTP",
   .respond_line = smtp_respond_line,
   .init = init,