Add config parsers for multiple tcp socket readers and a helper to see if we can offer it on the platform

1 files changed, 22 insertions, 4 deletions

diff --git a/ot_config.c b/ot_config.c
index a0dbef1..272acf1 100644
--- a/ot_config.c
+++ b/ot_config.c
@@ -14,6 +14,7 @@
 
 /* Opentracker */
 #include "ot_accesslist.h"
+#include "ot_event.h"
 #include "ot_config.h"
 #include "ot_http.h"
 #include "ot_ip.h"
@@ -32,7 +33,8 @@ const char   *g_statefile;
 static ot_listen *g_listen;
 static size_t     g_listen_count;
 static int        g_listen_shared;
-static int        g_listen_workers = 1;
+static int        g_listen_workers_udp = 1;
+static int        g_listen_workers_tcp = 0;
 
 static void panic(const char *routine) __attribute__((noreturn));
 static void panic(const char *routine) {
@@ -196,6 +198,7 @@ typedef enum {
     CONFIG_LISTEN_TCP,
     CONFIG_LISTEN_UDP,
     CONFIG_LISTEN_UDP_WORKERS,
+    CONFIG_LISTEN_TCP_WORKERS,
     CONFIG_LISTEN_SHARED,
     CONFIG_ACCESS_WHITELIST,
     CONFIG_ACCESS_BLACKLIST,
@@ -224,6 +227,7 @@ static const config_key config_keys[] = {
     CONFIG_KEY("listen.tcp",               CONFIG_LISTEN_TCP),
     CONFIG_KEY("listen.udp",               CONFIG_LISTEN_UDP),
     CONFIG_KEY("listen.udp.workers",       CONFIG_LISTEN_UDP_WORKERS),
+    CONFIG_KEY("listen.tcp.workers",       CONFIG_LISTEN_TCP_WORKERS),
     CONFIG_KEY("listen.shared",            CONFIG_LISTEN_SHARED),
 #ifdef WANT_ACCESSLIST_WHITE
     CONFIG_KEY("access.whitelist",         CONFIG_ACCESS_WHITELIST),
@@ -318,7 +322,7 @@ static int parse_configfile(char *config_filename) {
         if (!off || !listen_scan_options(p + off, &shared, &workers))
           goto parse_error;
         if (kind != CONFIG_LISTEN_UDP)
-          listen_append(tmpip, tmpport, FLAG_TCP, shared, OT_LISTEN_INHERIT), ++bound;
+          listen_append(tmpip, tmpport, FLAG_TCP, shared, workers), ++bound;
         if (kind != CONFIG_LISTEN_TCP)
           listen_append(tmpip, tmpport, FLAG_UDP, shared, workers), ++bound;
         break;
@@ -326,7 +330,12 @@ static int parse_configfile(char *config_filename) {
       case CONFIG_LISTEN_UDP_WORKERS:
         if (!scan_uint(p, &value, UINT_MAX))
           goto parse_error;
-        g_listen_workers = (int)value;
+        g_listen_workers_udp = (int)value;
+        break;
+      case CONFIG_LISTEN_TCP_WORKERS:
+        if (!scan_uint(p, &value, UINT_MAX))
+          goto parse_error;
+        g_listen_workers_tcp = (int)value;
         break;
       case CONFIG_LISTEN_SHARED:
         if (!scan_uint(p, &value, 1))
@@ -446,7 +455,16 @@ static void listen_resolve_defaults(void) {
     if (entry->shared == OT_LISTEN_INHERIT)
       entry->shared = g_listen_shared;
     if (entry->workers == OT_LISTEN_INHERIT)
-      entry->workers = g_listen_workers;
+      entry->workers = entry->proto == FLAG_TCP ? g_listen_workers_tcp : g_listen_workers_udp;
+
+    /* A tcp worker hands a connection it cannot finish to the event loop,
+       which only one thread may touch where the set is ours rather than the
+       kernel's */
+    if (entry->proto == FLAG_TCP && entry->workers > 1 && !event_can_share()) {
+      fprintf(stderr, "Warning: Multiple workers impossible on this platform with event mechanism %s chosen.\n",
+              event_mechanism());
+      entry->workers = 1;
+    }
   }
 }