Address CodeQL warning

https://github.com/rabbitmq/amqp091-go/security/code-scanning/1

.github/workflows/codeql-analysis.yml

@@ -38,9 +38,9 @@ jobs:
         # https://docs.github.com/en/free-pro-team@latest/github/finding-security-vulnerabilities-and-errors-in-your-code/configuring-code-scanning#changing-the-languages-that-are-analyzed
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@v3
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -51,7 +51,7 @@ jobs:
     # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
+      uses: github/codeql-action/autobuild@v3
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 https://git.io/JvXDl
@@ -65,4 +65,4 @@ jobs:
     #   make release
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
+      uses: github/codeql-action/analyze@v3

.github/workflows/golangci-lint.yml

@@ -14,12 +14,12 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/setup-go@v3
+      - uses: actions/setup-go@v5
         with:
           go-version: 'stable'
           check-latest: true
-      - uses: actions/checkout@v3
-      - uses: golangci/golangci-lint-action@v3
+      - uses: actions/checkout@v4
+      - uses: golangci/golangci-lint-action@v4
         with:
           version: latest
           only-new-issues: false

.github/workflows/tests.yml

@@ -15,8 +15,8 @@ jobs:
       matrix:
         go-version: ['oldstable', 'stable']
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-go@v3
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
         with:
           go-version: ${{ matrix.go-version }}
           check-latest: true
@@ -43,8 +43,8 @@ jobs:
         ports:
           - 5672:5672
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-go@v3
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
         with:
           go-version: ${{ matrix.go-version }}
           check-latest: true

connection.go

@@ -32,7 +32,7 @@ const (
 	platform                 = "golang"
 	// Safer default that makes channel leaks a lot easier to spot
 	// before they create operational headaches. See https://github.com/rabbitmq/rabbitmq-server/issues/1593.
-	defaultChannelMax = (2 << 10) - 1
+	defaultChannelMax = uint16((2 << 10) - 1)
 	defaultLocale     = "en_US"
 )
 
@@ -49,7 +49,7 @@ type Config struct {
 	// bindings on the server.  Dial sets this to the path parsed from the URL.
 	Vhost string
 
-	ChannelMax int           // 0 max channels means 2^16 - 1
+	ChannelMax uint16        // 0 max channels means 2^16 - 1
 	FrameSize  int           // 0 max bytes means unlimited
 	Heartbeat  time.Duration // less than 1s uses the server's interval
 
@@ -991,13 +991,13 @@ func (c *Connection) openTune(config Config, auth Authentication) error {
 
 	// When the server and client both use default 0, then the max channel is
 	// only limited by uint16.
-	c.Config.ChannelMax = pick(config.ChannelMax, int(tune.ChannelMax))
+	c.Config.ChannelMax = pickUInt16(config.ChannelMax, tune.ChannelMax)
 	if c.Config.ChannelMax == 0 {
 		c.Config.ChannelMax = defaultChannelMax
 	}
-	c.Config.ChannelMax = min(c.Config.ChannelMax, maxChannelMax)
+	c.Config.ChannelMax = minUInt16(c.Config.ChannelMax, maxChannelMax)
 
-	c.allocator = newAllocator(1, c.Config.ChannelMax)
+	c.allocator = newAllocator(1, int(c.Config.ChannelMax))
 
 	c.m.Unlock()
 
@@ -1104,13 +1104,35 @@ func max(a, b int) int {
 	return b
 }
 
+func maxUInt16(a, b uint16) uint16 {
+	if a > b {
+		return a
+	}
+	return b
+}
+
 func min(a, b int) int {
 	if a < b {
 		return a
 	}
 	return b
 }
 
+func minUInt16(a, b uint16) uint16 {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func pickUInt16(client, server uint16) uint16 {
+	if client == 0 || server == 0 {
+		return maxUInt16(client, server)
+	} else {
+		return minUInt16(client, server)
+	}
+}
+
 func pick(client, server int) int {
 	if client == 0 || server == 0 {
 		return max(client, server)

integration_test.go

@@ -478,7 +478,7 @@ func TestIntegrationChannelIDsExhausted(t *testing.T) {
 	}
 	defer c.Close()
 
-	for i := 1; i <= c.Config.ChannelMax; i++ {
+	for i := uint16(1); i <= c.Config.ChannelMax; i++ {
 		if _, err := c.Channel(); err != nil {
 			t.Fatalf("expected allocating all channel ids to succed, failed on %d with %v", i, err)
 		}