fix(proxy): retry raced dynamic port binds

src/commands/proxy-command.ts

@@ -199,7 +199,7 @@ export async function handleProxyCommand(args: string[]): Promise<number> {
     case 'start':
       return handleStart(args.slice(1));
     case 'stop': {
-      const profileName = args[1] && !args[1]?.startsWith('-') ? args[1] : undefined;
+      const profileName = args[1] && !args[1].startsWith('-') ? args[1] : undefined;
       const result = await stopOpenAICompatProxy(profileName);
       if (!result.success) {
         console.error(fail(result.error || 'Failed to stop proxy'));

src/proxy/proxy-daemon.ts

@@ -93,12 +93,17 @@ async function isPortOccupied(port: number): Promise<boolean> {
   });
 }
 
-async function findOpenAICompatProxyPort(): Promise<number> {
+async function findOpenAICompatProxyPort(
+  excludedPorts: ReadonlySet<number> = new Set()
+): Promise<number> {
   for (
     let candidate = OPENAI_COMPAT_PROXY_DEFAULT_PORT;
     candidate <= OPENAI_COMPAT_PROXY_DEFAULT_PORT + 10;
     candidate += 1
   ) {
+    if (excludedPorts.has(candidate)) {
+      continue;
+    }
     if (!(await isPortOccupied(candidate))) {
       return candidate;
     }
@@ -107,11 +112,14 @@ async function findOpenAICompatProxyPort(): Promise<number> {
   return 0;
 }
 
-async function findOpenAICompatProxyPortNear(preferredPort: number): Promise<number> {
+async function findOpenAICompatProxyPortNear(
-  if (!(await isPortOccupied(preferredPort))) {
+  preferredPort: number,
+  excludedPorts: ReadonlySet<number> = new Set()
+): Promise<number> {
+  if (!excludedPorts.has(preferredPort) && !(await isPortOccupied(preferredPort))) {
     return preferredPort;
   }
-  return findOpenAICompatProxyPort();
+  return findOpenAICompatProxyPort(excludedPorts);
 }
 
 interface OpenAICompatProxyStateRecord {
@@ -350,36 +358,23 @@ export async function startOpenAICompatProxy(
         ? portPreference.port
         : status.port || portPreference.port);
     const requiresExactPort = explicitPort !== undefined || portPreference.source === 'profile';
-    const port =
+    if (status.running && status.port === preferredPort && (status.host || '127.0.0.1') === host) {
-      status.running && status.port && (status.host || '127.0.0.1') === host
-        ? status.port
-        : requiresExactPort
-          ? preferredPort
-          : await findOpenAICompatProxyPortNear(preferredPort);
-    if (port === 0) {
-      return {
-        success: false,
-        port: preferredPort,
-        error: `No free proxy port found in range ${OPENAI_COMPAT_PROXY_DEFAULT_PORT}-${OPENAI_COMPAT_PROXY_DEFAULT_PORT + 10}`,
-      };
-    }
-    if (!Number.isInteger(port) || port < 1 || port > 65535) {
-      return { success: false, port, error: `Invalid port: ${port}` };
-    }
-    if (status.running && status.port === port && (status.host || '127.0.0.1') === host) {
       return {
         success: true,
         alreadyRunning: true,
         pid: status.pid,
-        port,
+        port: preferredPort,
         authToken: status.authToken,
       };
     }
-    if (requiresExactPort && (await isPortOccupied(port))) {
+    if (!Number.isInteger(preferredPort) || preferredPort < 1 || preferredPort > 65535) {
+      return { success: false, port: preferredPort, error: `Invalid port: ${preferredPort}` };
+    }
+    if (requiresExactPort && (await isPortOccupied(preferredPort))) {
       return {
         success: false,
-        port,
+        port: preferredPort,
-        error: `Requested proxy port ${port} is already in use`,
+        error: `Requested proxy port ${preferredPort} is already in use`,
       };
     }
     if (status.running) {
@@ -387,7 +382,7 @@ export async function startOpenAICompatProxy(
       if (!stopped.success) {
         return {
           success: false,
-          port,
+          port: preferredPort,
           error: stopped.error || 'Failed to restart the running proxy',
         };
       }
@@ -397,12 +392,13 @@ export async function startOpenAICompatProxy(
     if (!daemonEntry) {
       return {
         success: false,
-        port,
+        port: preferredPort,
         error: 'OpenAI proxy daemon entrypoint not found. Run `bun run build` and retry.',
       };
     }
 
-    return new Promise((resolve) => {
+    const startOnPort = (port: number): Promise<StartOpenAICompatProxyResult> =>
+      new Promise((resolve) => {
         let resolved = false;
         let timeout: NodeJS.Timeout | null = null;
         const authToken = generateProxyAuthToken();
@@ -499,5 +495,41 @@ export async function startOpenAICompatProxy(
           });
         });
       });
+
+    if (requiresExactPort) {
+      return startOnPort(preferredPort);
+    }
+
+    const attemptedPorts = new Set<number>();
+    let lastResult: StartOpenAICompatProxyResult | null = null;
+    for (let attempt = 0; attempt < 3; attempt += 1) {
+      const port = await findOpenAICompatProxyPortNear(preferredPort, attemptedPorts);
+      if (port === 0) {
+        return {
+          success: false,
+          port: preferredPort,
+          error: `No free proxy port found in range ${OPENAI_COMPAT_PROXY_DEFAULT_PORT}-${OPENAI_COMPAT_PROXY_DEFAULT_PORT + 10}`,
+        };
+      }
+
+      const result = await startOnPort(port);
+      if (result.success) {
+        return result;
+      }
+
+      lastResult = result;
+      attemptedPorts.add(port);
+      if (!(await isPortOccupied(port))) {
+        return result;
+      }
+    }
+
+    return (
+      lastResult ?? {
+        success: false,
+        port: preferredPort,
+        error: 'Failed to start proxy',
+      }
+    );
   });
 }