Loggers: no blocks flag

A logger's lines are written by a thread of its own, its clients only
queueing them, so a logger whose writes wait cannot hold a client's
thread or a loop: its blocks flag, giving its services a thread for each
client, is gone. ODBC was the logger setting it; its services are served
on loops now too. Only a logger whose thread could not be started is
written by its clients themselves, as before.

Plugins: struct logtype loses its last member, blocks.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/mainconf.c

@@ -652,7 +652,6 @@ static int srvprepare(struct srvstart *s, int argc, char **argv){
     other client */
  if(srv->o_nsfd >= 0) srv->threadperclient = 1;
 #endif
- if(srv->logger && srv->logger->type && srv->logger->type->blocks) srv->threadperclient = 1;
 #ifndef STDMAIN
  if(sysresolves(srv->resolvmode)) srv->threadperclient = 1;
 #endif

src/sql.c

@@ -132,7 +132,7 @@ static void odbcclose(struct logger *lg){
 }
 
 const struct logtype logtype_odbc = {
-    "odbc", odbcmatch, odbcinit, odbcformat, odbcwrite, odbcclose, NULL, LOGSTACKSIZE, 0, 0, 1, 1
+    "odbc", odbcmatch, odbcinit, odbcformat, odbcwrite, odbcclose, NULL, LOGSTACKSIZE, 0, 0, 1
 };
 
 #endif

src/structures.h

@@ -668,7 +668,6 @@ struct logtype {
 	int standard;	/* kept open for the life of the process */
 	int text;	/* writes a line of text: errors can go there */
 	int params;	/* the string after a comma is parameters */
-	int blocks;	/* waits for its writes other than in sockpoll() */
 };
 
 /* What a log's queue holds: a line (log.c's struct logslot, of which this