From 9c7a2e91285ca91d500cc828ad041a264128db4d Mon Sep 17 00:00:00 2001
From: Xavier Del Campo Romero <xavi.dcr@tutanota.com>
Date: Mon, 1 May 2023 03:06:34 +0200
Subject: [PATCH] Avoid crashing on SIGPIPE

Under some circumstances, clients could cause SIGPIPE to slcl. Since
this signal was not handled by server.c (i.e., via sigaction(3)), slcl
would crash without any error messages printed to stderr.

In such situation, SIGPIPE should not be usually considered a fatal
error, so it is preferrable to close the connection and keep working.
---
 http.c   |  2 ++
 server.c | 20 ++++++++++++++++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/http.c b/http.c
index 501499b..d843bb5 100644
--- a/http.c
+++ b/http.c
@@ -496,6 +496,8 @@ static int rw_error(const int r, bool *const close)
     {
         switch (errno)
         {
+            case EPIPE:
+                /* Fall through. */
             case ECONNRESET:
                 *close = true;
                 return 1;
diff --git a/server.c b/server.c
index a561bfb..afecf3a 100644
--- a/server.c
+++ b/server.c
@@ -167,7 +167,17 @@ static volatile sig_atomic_t do_exit;
 
 static void handle_signal(const int signum)
 {
-    do_exit = 1;
+    switch (signum)
+    {
+        case SIGINT:
+            /* Fall through. */
+        case SIGTERM:
+            do_exit = 1;
+            break;
+
+        default:
+            break;
+    }
 }
 
 struct server_client *server_poll(struct server *const s, bool *const io,
@@ -286,7 +296,13 @@ static int init_signals(void)
     }
     else if (sigaction(SIGTERM, &sa, NULL))
     {
-        fprintf(stderr, "%s: sigaction(2) SIGINT: %s\n",
+        fprintf(stderr, "%s: sigaction(2) SIGTERM: %s\n",
+            __func__, strerror(errno));
+        return -1;
+    }
+    else if (sigaction(SIGPIPE, &sa, NULL))
+    {
+        fprintf(stderr, "%s: sigaction(2) SIGPIPE: %s\n",
             __func__, strerror(errno));
         return -1;
     }