From 3f9b164e67dd32fefab247cbcac7a94b09b7bdd9 Mon Sep 17 00:00:00 2001
From: Michael Ortmann <keine email>
Date: Tue, 2 Apr 2024 01:38:18 +0200
Subject: [PATCH 1/6] defer debug() / putlog() from dns threads to main thread
 via dtn.strerror

---
 src/dns.c     | 19 +++++++++++--------
 src/eggdrop.h |  2 +-
 src/net.c     |  6 ++++--
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/src/dns.c b/src/dns.c
index 2e5035b88..2ad84a631 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -492,6 +492,8 @@ void call_ipbyhost(char *hostn, sockname_t *ip, int ok)
  * is closed and the thread is ended by return. The other end will make
  * eggdrops mainloop select() return, read the result from the dns_thread_node
  * and call call_hostbyip() or call_ipbyhost(). No signal or tcl thread problem.
+ *
+ * defer debug() / putlog() from dns threads to main thread via dtn.strerror
  */
 
 void *thread_dns_hostbyip(void *arg)
@@ -502,8 +504,10 @@ void *thread_dns_hostbyip(void *arg)
 
   i = getnameinfo((const struct sockaddr *) &addr->addr.sa, addr->addrlen,
                   dtn->host, sizeof dtn->host, NULL, 0, 0);
-  if (i) {
-    debug1("dns: thread_dns_hostbyip(): getnameinfo(): error = %s", gai_strerror(i));
+  if (!i)
+    *dtn->strerror = 0;
+  else {
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_hostbyip(): getnameinfo(): hostname %s: %s", dtn->host, gai_strerror(i));
 #ifdef IPV6
     if (addr->family == AF_INET6)
       inet_ntop(AF_INET6, &addr->addr.s6.sin6_addr, dtn->host, sizeof dtn->host);
@@ -512,7 +516,6 @@ void *thread_dns_hostbyip(void *arg)
       inet_ntop(AF_INET, &addr->addr.s4.sin_addr.s_addr, dtn->host, sizeof dtn->host);
   }
   pthread_mutex_lock(&dtn->mutex);
-  dtn->ok = !i;
   close(dtn->fildes[1]);
   pthread_mutex_unlock(&dtn->mutex);
   return NULL;
@@ -528,6 +531,7 @@ void *thread_dns_ipbyhost(void *arg)
   error = getaddrinfo(dtn->host, NULL, NULL, &res0);
   memset(addr, 0, sizeof *addr);
   if (!error) {
+    *dtn->strerror = 0;
 #ifdef IPV6
     for (res = res0; res; res = res->ai_next) {
       if (res == res0 || res->ai_family == (pref_af ? AF_INET6 : AF_INET)) {
@@ -539,13 +543,13 @@ void *thread_dns_ipbyhost(void *arg)
       }
     }
 #else
-    error = 1;
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): hostname %s: no ipv4", dtn->host);
     for (res = res0; res; res = res->ai_next) {
       if (res->ai_family == AF_INET) {
         addr->family = res->ai_family;
         addr->addrlen = res->ai_addrlen;
         memcpy(&addr->addr.sa, res->ai_addr, res->ai_addrlen);
-        error = 0;
+        *dtn->strerror = 0;
         break;
       }
     }
@@ -555,11 +559,10 @@ void *thread_dns_ipbyhost(void *arg)
       freeaddrinfo(res0);
   }
   else if (error == EAI_NONAME)
-    debug1("dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s not known", dtn->host);
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: not known", dtn->host);
   else
-    debug1("dns: thread_dns_ipbyhost(): getaddrinfo(): error = %s", gai_strerror(error));
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: %s", dtn->host, gai_strerror(error));
   pthread_mutex_lock(&dtn->mutex);
-  dtn->ok = !error;
   close(dtn->fildes[1]);
   pthread_mutex_unlock(&dtn->mutex);
   return NULL;
diff --git a/src/eggdrop.h b/src/eggdrop.h
index 076a16252..a2855192c 100644
--- a/src/eggdrop.h
+++ b/src/eggdrop.h
@@ -757,7 +757,7 @@ struct dns_thread_node {
   int type;
   sockname_t addr;
   char host[256];
-  int ok;
+  char strerror[319];
   struct dns_thread_node *next;
 };
 
diff --git a/src/net.c b/src/net.c
index c8aa62cd5..c53c70381 100644
--- a/src/net.c
+++ b/src/net.c
@@ -1053,16 +1053,18 @@ int sockread(char *s, int *len, sock_list *slist, int slistmax, int tclonly)
 #ifdef EGG_TDNS
   dtn_prev = dns_thread_head;
   for (dtn = dtn_prev->next; dtn; dtn = dtn->next) {
+    if (*dtn->strerror)
+      debug0(dtn->strerror);
     fd = dtn->fildes[0];
     if (FD_ISSET(fd, &fdr)) {
       if (dtn->type == DTN_TYPE_HOSTBYIP) {
         pthread_mutex_lock(&dtn->mutex);
-        call_hostbyip(&dtn->addr, dtn->host, dtn->ok);
+        call_hostbyip(&dtn->addr, dtn->host, !*dtn->strerror);
         pthread_mutex_unlock(&dtn->mutex);
       }
       else {
         pthread_mutex_lock(&dtn->mutex);
-        call_ipbyhost(dtn->host, &dtn->addr, dtn->ok);
+        call_ipbyhost(dtn->host, &dtn->addr, !*dtn->strerror);
         pthread_mutex_unlock(&dtn->mutex);
       }
       close(dtn->fildes[0]);

From 902d224b44e67270b72b38b8b4e44e95e3d0d2bb Mon Sep 17 00:00:00 2001
From: Michael Ortmann <keine email>
Date: Tue, 2 Apr 2024 03:55:49 +0200
Subject: [PATCH 2/6] Cleanup - call snprintf() only if we have to

---
 src/dns.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/dns.c b/src/dns.c
index 2ad84a631..893996db0 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -543,16 +543,19 @@ void *thread_dns_ipbyhost(void *arg)
       }
     }
 #else
-    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): hostname %s: no ipv4", dtn->host);
+    error = 1;
     for (res = res0; res; res = res->ai_next) {
       if (res->ai_family == AF_INET) {
         addr->family = res->ai_family;
         addr->addrlen = res->ai_addrlen;
         memcpy(&addr->addr.sa, res->ai_addr, res->ai_addrlen);
+	error = 0;
         *dtn->strerror = 0;
         break;
       }
     }
+    if (error)
+      snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): hostname %s: no ipv4", dtn->host);
 #endif
     if (res0) /* The behavior of freeadrinfo(NULL) is left unspecified by RFCs
                * 2553 and 3493. Avoid to be compatible with all OSes. */

From c4a3b4db20a471ad3a2f6ec2b363564eea5337bf Mon Sep 17 00:00:00 2001
From: Michael Ortmann <keine email>
Date: Tue, 2 Apr 2024 04:03:42 +0200
Subject: [PATCH 3/6] fix buf size for long hostnames

---
 src/eggdrop.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/eggdrop.h b/src/eggdrop.h
index a2855192c..45b8411b4 100644
--- a/src/eggdrop.h
+++ b/src/eggdrop.h
@@ -757,7 +757,7 @@ struct dns_thread_node {
   int type;
   sockname_t addr;
   char host[256];
-  char strerror[319];
+  char strerror[256 + 128]; /* hostname + gai_strerror() + msg */
   struct dns_thread_node *next;
 };
 

From ba18ffbdb0f0f2f2a9d4cae9bc83b2fdc54f40af Mon Sep 17 00:00:00 2001
From: Michael Ortmann <keine email>
Date: Sun, 28 Apr 2024 23:33:36 +0200
Subject: [PATCH 4/6] enhance error logging

---
 src/dns.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/dns.c b/src/dns.c
index 893996db0..883c29fbb 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -563,6 +563,8 @@ void *thread_dns_ipbyhost(void *arg)
   }
   else if (error == EAI_NONAME)
     snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: not known", dtn->host);
+  else if (error == EAI_SYSTEM)
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: %s: %s", dtn->host, gai_strerror(error), strerror(errno));
   else
     snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: %s", dtn->host, gai_strerror(error));
   pthread_mutex_lock(&dtn->mutex);

From c72cc1c551d2569e1b1ae4551909ddb9b7f40a89 Mon Sep 17 00:00:00 2001
From: Michael Ortmann <keine email>
Date: Sun, 28 Apr 2024 23:59:10 +0200
Subject: [PATCH 5/6] Enhance memory usage by reusing dtn->host

---
 src/dns.c     | 10 +++++-----
 src/eggdrop.h |  2 +-
 src/net.c     |  2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/dns.c b/src/dns.c
index 883c29fbb..94e41618d 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -507,7 +507,7 @@ void *thread_dns_hostbyip(void *arg)
   if (!i)
     *dtn->strerror = 0;
   else {
-    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_hostbyip(): getnameinfo(): hostname %s: %s", dtn->host, gai_strerror(i));
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_hostbyip(): getnameinfo(): %s", gai_strerror(i));
 #ifdef IPV6
     if (addr->family == AF_INET6)
       inet_ntop(AF_INET6, &addr->addr.s6.sin6_addr, dtn->host, sizeof dtn->host);
@@ -555,18 +555,18 @@ void *thread_dns_ipbyhost(void *arg)
       }
     }
     if (error)
-      snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): hostname %s: no ipv4", dtn->host);
+      snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): no ipv4");
 #endif
     if (res0) /* The behavior of freeadrinfo(NULL) is left unspecified by RFCs
                * 2553 and 3493. Avoid to be compatible with all OSes. */
       freeaddrinfo(res0);
   }
   else if (error == EAI_NONAME)
-    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: not known", dtn->host);
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): not known");
   else if (error == EAI_SYSTEM)
-    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: %s: %s", dtn->host, gai_strerror(error), strerror(errno));
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): %s: %s", gai_strerror(error), strerror(errno));
   else
-    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): hostname %s: %s", dtn->host, gai_strerror(error));
+    snprintf(dtn->strerror, sizeof dtn->strerror, "dns: thread_dns_ipbyhost(): getaddrinfo(): %s", gai_strerror(error));
   pthread_mutex_lock(&dtn->mutex);
   close(dtn->fildes[1]);
   pthread_mutex_unlock(&dtn->mutex);
diff --git a/src/eggdrop.h b/src/eggdrop.h
index 45b8411b4..54babf7b0 100644
--- a/src/eggdrop.h
+++ b/src/eggdrop.h
@@ -757,7 +757,7 @@ struct dns_thread_node {
   int type;
   sockname_t addr;
   char host[256];
-  char strerror[256 + 128]; /* hostname + gai_strerror() + msg */
+  char strerror[256]; /* msg + gai_strerror() + strerror() */
   struct dns_thread_node *next;
 };
 
diff --git a/src/net.c b/src/net.c
index c53c70381..8196d2b6e 100644
--- a/src/net.c
+++ b/src/net.c
@@ -1054,7 +1054,7 @@ int sockread(char *s, int *len, sock_list *slist, int slistmax, int tclonly)
   dtn_prev = dns_thread_head;
   for (dtn = dtn_prev->next; dtn; dtn = dtn->next) {
     if (*dtn->strerror)
-      debug0(dtn->strerror);
+      debug2("%s: hostname %s", dtn->strerror, dtn->host);
     fd = dtn->fildes[0];
     if (FD_ISSET(fd, &fdr)) {
       if (dtn->type == DTN_TYPE_HOSTBYIP) {

From 0103227708c3d9f24a05dd39c340f536ef097f0f Mon Sep 17 00:00:00 2001
From: Michael Ortmann <keine email>
Date: Mon, 29 Apr 2024 00:55:38 +0200
Subject: [PATCH 6/6] enhance memory usage

---
 src/eggdrop.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/eggdrop.h b/src/eggdrop.h
index 54babf7b0..04296062d 100644
--- a/src/eggdrop.h
+++ b/src/eggdrop.h
@@ -757,7 +757,7 @@ struct dns_thread_node {
   int type;
   sockname_t addr;
   char host[256];
-  char strerror[256]; /* msg + gai_strerror() + strerror() */
+  char strerror[3 * 64]; /* msg + gai_strerror() + strerror() */
   struct dns_thread_node *next;
 };