MODE: Reply with ERR_NOSUCHCHANNEL when the target is a channel (#319)

While it is common for IRC servers to use ERR_NOSUCHNICK instead of
ERR_NOSUCHCHANNEL when a target can be either a channel or a nick, it seems
every other IRCd but UnrealIRCd uses ERR_NOSUCHCHANNEL in this particular case.

.github/workflows/ci.yml

@@ -28,32 +28,53 @@ on:
 
 jobs:
   build_and_distcheck:
-
-    name: Configure ngIRCd sources and run make targets "all" and "distcheck"
-    runs-on: ubuntu-latest
-    timeout-minutes: 10
-
+    name: build+test
+    strategy:
+      matrix:
+        os:
+          - ubuntu
+          - macos
+        toolchain:
+          - gcc
+          - llvm
+        include:
+          - os: ubuntu
+            toolchain: gcc
+            install_cmd: |
+              sudo apt update
+              sudo apt install build-essential expect libident-dev libpam0g-dev libssl-dev libwrap0-dev pkg-config telnet zlib1g-dev gcc
+            configure_cmd: |
+              ./configure CC=gcc --enable-ipv6 --with-iconv --with-ident --with-openssl --with-pam --with-tcp-wrappers --with-zlib
+          - os: ubuntu
+            toolchain: llvm
+            install_cmd: |
+              sudo apt update
+              sudo apt install build-essential expect libident-dev libpam0g-dev libssl-dev libwrap0-dev pkg-config telnet zlib1g-dev clang
+            configure_cmd: |
+              ./configure CC=clang --enable-ipv6 --with-iconv --with-ident --with-openssl --with-pam --with-tcp-wrappers --with-zlib  
+          - os: macos
+            toolchain: gcc
+            install_cmd: |
+              brew update
+              brew install autoconf automake expect openssl@3 pkg-config telnet zlib gcc
+            configure_cmd: |
+              ./configure CC=gcc --enable-ipv6 --with-iconv --with-openssl --with-zlib
+          - os: macos
+            toolchain: llvm
+            install_cmd: |
+              brew update
+              brew install autoconf automake expect openssl@3 pkg-config telnet zlib llvm
+            configure_cmd: |
+              ./configure CC=clang --enable-ipv6 --with-iconv --with-openssl --with-zlib
+    runs-on: ${{ matrix.os }}-latest
     steps:
     - uses: actions/checkout@v4
-    - uses: awalsh128/cache-apt-pkgs-action@v1
-      with:
-        packages: >
-          autoconf
-          automake
-          build-essential
-          expect
-          libident-dev
-          libpam0g-dev
-          libssl-dev
-          libwrap0-dev
-          pkg-config
-          telnet
-          zlib1g-dev
-        version: 1.0
+    - name: Install dependencies
+      run: ${{ matrix.install_cmd }}
     - name: Generate build system files
       run: ./autogen.sh
     - name: Configure the build system
-      run: ./configure --enable-ipv6 --with-iconv --with-ident --with-openssl --with-pam --with-tcp-wrappers --with-zlib
+      run: ${{ matrix.configure_cmd }}
     - name: Build everything
       run: make all
     - name: Create distribution archive and run tests

src/ngircd/irc-mode.c

@@ -62,6 +62,7 @@ IRC_MODE( CLIENT *Client, REQUEST *Req )
 {
 	CLIENT *cl, *origin;
 	CHANNEL *chan;
+	bool is_valid_nick, is_valid_chan;
 
 	assert(Client != NULL);
 	assert(Req != NULL);
@@ -76,10 +77,12 @@ IRC_MODE( CLIENT *Client, REQUEST *Req )
 		Client = Client_Search(Req->prefix);
 
 	/* Channel or user mode? */
+	is_valid_nick = Client_IsValidNick(Req->argv[0]);
+	is_valid_chan = Channel_IsValidName(Req->argv[0]);
 	cl = NULL; chan = NULL;
-	if (Client_IsValidNick(Req->argv[0]))
+	if (is_valid_nick)
 		cl = Client_Search(Req->argv[0]);
-	if (Channel_IsValidName(Req->argv[0]))
+	if (is_valid_chan)
 		chan = Channel_Search(Req->argv[0]);
 
 	if (cl)
@@ -88,8 +91,12 @@ IRC_MODE( CLIENT *Client, REQUEST *Req )
 		return Channel_Mode(Client, Req, origin, chan);
 
 	/* No target found! */
-	return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG,
-			Client_ID(Client), Req->argv[0]);
+	if (is_valid_nick)
+		return IRC_WriteErrClient(Client, ERR_NOSUCHNICK_MSG,
+				Client_ID(Client), Req->argv[0]);
+	else
+		return IRC_WriteErrClient(Client, ERR_NOSUCHCHANNEL_MSG,
+				Client_ID(Client), Req->argv[0]);
 } /* IRC_MODE */
 
 /**