tty: some improvements to pass posix_openpt_test.

WriterLocker::AcquireWriter(): don't fail when the other end isn't yet opened.
WriterLocker::_CheckBackgroundWrite(): don't fail when the pgrp_id differs.
ReaderLocker::AcquireReader(): fail when the other end isn't opened anymore.
ReaderLocker::AcquireReader(): check available bytes even in case of failure.
ReaderLocker::_CheckBackgroundRead(): don't fail when the pgrp_id differs.

Change-Id: Ice2bd119cbec2afc9ebd40714e4307856f540ea2
Reviewed-on: https://review.haiku-os.org/c/1418
Reviewed-by: Jérôme Duval <[email protected]>

src/add-ons/kernel/drivers/tty/master.cpp

@@ -84,6 +84,8 @@ master_open(const char *name, uint32 flags, void **_cookie)
 		return B_BUSY;
 	}
 
+	gMasterTTYs[index].opened_count = 0;
+	gSlaveTTYs[index].opened_count = 0;
 	status_t status = tty_open(&gMasterTTYs[index], &master_service);
 	if (status < B_OK) {
 		// initializing TTY failed

src/add-ons/kernel/drivers/tty/tty.cpp

@@ -617,12 +617,8 @@ WriterLocker::AcquireWriter(bool dontBlock, size_t bytesNeeded)
 	if (status == B_OK)
 		status = _CheckBackgroundWrite();
 
-	if (status == B_OK) {
+	if (status == B_OK)
-		if (fTarget->open_count > 0)
+		fBytes = _CheckAvailableBytes();
-			fBytes = _CheckAvailableBytes();
-		else
-			status = B_FILE_ERROR;
-	}
 
 	return status;
 }
@@ -642,7 +638,6 @@ WriterLocker::_CheckBackgroundWrite() const
 			&& processGroup != fSource->settings->pgrp_id) {
 		if (team_get_controlling_tty() == fSource->index)
 			send_signal(-processGroup, SIGTTOU);
-		return EIO;
 	}
 
 	return B_OK;
@@ -701,6 +696,13 @@ ReaderLocker::AcquireReader(bigtime_t timeout, size_t bytesNeeded)
 			return B_OK;
 	}
 
+	if (fCookie->other_tty->open_count == 0
+		&& fCookie->other_tty->opened_count > 0) {
+		TRACE(("ReaderLocker::AcquireReader() opened_count %" B_PRId32 "\n",
+			fCookie->other_tty->opened_count));
+		return B_FILE_ERROR;
+	}
+
 	// We are not the first in queue or currently there's nothing to read:
 	// bail out, if we shall not block.
 	if (timeout <= 0)
@@ -717,8 +719,10 @@ ReaderLocker::AcquireReader(bigtime_t timeout, size_t bytesNeeded)
 	if (status == B_OK)
 		status = _CheckBackgroundRead();
 
-	if (status == B_OK)
+	fBytes = _CheckAvailableBytes();
-		fBytes = _CheckAvailableBytes();
+
+	TRACE(("ReaderLocker::AcquireReader() ended status 0x%" B_PRIx32 "\n",
+		status));
 
 	return status;
 }
@@ -751,7 +755,6 @@ ReaderLocker::_CheckBackgroundRead() const
 			&& processGroup != fTTY->settings->pgrp_id) {
 		if (team_get_controlling_tty() == fTTY->index)
 			send_signal(-processGroup, SIGTTIN);
-		return EIO;
 	}
 
 	return B_OK;
@@ -825,6 +828,7 @@ reset_tty(struct tty* tty, int32 index, mutex* lock, bool isMaster)
 {
 	tty->ref_count = 0;
 	tty->open_count = 0;
+	tty->opened_count = 0;
 	tty->index = index;
 	tty->lock = lock;
 	tty->settings = &gTTYSettings[index];
@@ -998,6 +1002,7 @@ add_tty_cookie(tty_cookie* cookie)
 	// add to the TTY's cookie list
 	cookie->tty->cookies.Add(cookie);
 	cookie->tty->open_count++;
+	cookie->tty->opened_count++;
 }
 
 
@@ -1872,10 +1877,12 @@ tty_input_read(tty_cookie* cookie, void* _buffer, size_t* _length)
 		TRACE(("tty_input_read: AcquireReader(%" B_PRIdBIGTIME "us, %ld)\n",
 			timeout, bytesNeeded));
 		status = locker.AcquireReader(timeout, bytesNeeded);
-		if (status != B_OK)
-			break;
-
 		size_t toRead = locker.AvailableBytes();
+		if (status != B_OK && toRead == 0) {
+			TRACE(("tty_input_read() AcquireReader failed\n"));
+			break;
+		}
+
 		if (toRead > length)
 			toRead = length;
 
@@ -1914,6 +1921,8 @@ tty_input_read(tty_cookie* cookie, void* _buffer, size_t* _length)
 			status = B_OK;
 	}
 
+	TRACE(("tty_input_read() status 0x%" B_PRIx32 "\n", status));
+
 	return *_length == 0 ? status : B_OK;
 }
 

src/add-ons/kernel/drivers/tty/tty_private.h

@@ -131,6 +131,7 @@ struct tty_settings {
 struct tty {
 	int32				ref_count;	// referenced by cookies
 	int32				open_count;
+	int32				opened_count;
 	int32				index;
 	struct mutex*		lock;
 	tty_settings*		settings;

src/add-ons/kernel/generic/tty/tty.cpp

@@ -170,7 +170,7 @@ public:
 
 		if (semaphore >= 0) {
 			TRACE(("TTYReference: cookie %p closed, last operation done, "
-				"releasing blocking sem %ld\n", cookie, semaphore));
+				"releasing blocking sem %" B_PRId32 "\n", cookie, semaphore));
 
 			release_sem(semaphore);
 		}
@@ -419,8 +419,8 @@ RequestOwner::Wait(bool interruptable, bigtime_t timeout)
 			(interruptable ? B_CAN_INTERRUPT : 0) | B_RELATIVE_TIMEOUT,
 			timeout);
 
-		TRACE(("%p->RequestOwner::Wait(): condition occurred: %lx\n", this,
+		TRACE(("%p->RequestOwner::Wait(): condition occurred: %" B_PRIx32 "\n",
-			error));
+			this, error));
 
 		// remove the condition variable
 		locker.Lock();
@@ -474,7 +474,8 @@ RequestOwner::Notify(Request* request)
 void
 RequestOwner::NotifyError(Request* request, status_t error)
 {
-	TRACE(("%p->RequestOwner::NotifyError(%p, %lx)\n", this, request, error));
+	TRACE(("%p->RequestOwner::NotifyError(%p, %" B_PRIx32 ")\n", this, request,
+		error));
 
 	if (fError == B_OK) {
 		fError = error;
@@ -602,12 +603,8 @@ WriterLocker::AcquireWriter(bool dontBlock, size_t bytesNeeded)
 		status = fRequestOwner.Error();
 	}
 
-	if (status == B_OK) {
+	if (status == B_OK)
-		if (fTarget->open_count > 0)
+		fBytes = _CheckAvailableBytes();
-			fBytes = _CheckAvailableBytes();
-		else
-			status = B_FILE_ERROR;
-	}
 
 	return status;
 }
@@ -661,6 +658,13 @@ ReaderLocker::AcquireReader(bigtime_t timeout, size_t bytesNeeded)
 			return B_OK;
 	}
 
+	if (fCookie->other_tty->open_count == 0
+		&& fCookie->other_tty->opened_count > 0) {
+		TRACE(("ReaderLocker::AcquireReader() opened_count %" B_PRId32 "\n",
+			fCookie->other_tty->opened_count));
+		return B_FILE_ERROR;
+	}
+
 	// We are not the first in queue or currently there's nothing to read:
 	// bail out, if we shall not block.
 	if (timeout <= 0)
@@ -674,8 +678,10 @@ ReaderLocker::AcquireReader(bigtime_t timeout, size_t bytesNeeded)
 	status_t status = fRequestOwner.Wait(true, timeout);
 	Lock();
 
-	if (status == B_OK)
+	fBytes = _CheckAvailableBytes();
-		fBytes = _CheckAvailableBytes();
+
+	TRACE(("ReaderLocker::AcquireReader() ended status 0x%" B_PRIx32 "\n",
+		status));
 
 	return status;
 }
@@ -1328,6 +1334,7 @@ tty_create(tty_service_func func, bool isMaster)
 
 	tty->ref_count = 0;
 	tty->open_count = 0;
+	tty->opened_count = 0;
 	tty->select_pool = NULL;
 	tty->is_master = isMaster;
 	tty->pending_eof = 0;
@@ -1391,6 +1398,7 @@ tty_create_cookie(struct tty* tty, struct tty* otherTTY, uint32 openMode)
 	tty->cookies.Add(cookie);
 	tty->open_count++;
 	tty->ref_count++;
+	tty->opened_count++;
 
 	return cookie;
 }
@@ -1568,10 +1576,12 @@ tty_read(tty_cookie* cookie, void* _buffer, size_t* _length)
 		TRACE(("tty_input_read: AcquireReader(%Ldus, %ld)\n", timeout,
 			bytesNeeded));
 		status = locker.AcquireReader(timeout, bytesNeeded);
-		if (status != B_OK)
-			break;
-
 		size_t toRead = locker.AvailableBytes();
+		if (status != B_OK && toRead == 0) {
+			TRACE(("tty_input_read() AcquireReader failed\n"));
+			break;
+		}
+
 		if (toRead > length)
 			toRead = length;
 
@@ -1610,6 +1620,8 @@ tty_read(tty_cookie* cookie, void* _buffer, size_t* _length)
 			status = B_OK;
 	}
 
+	TRACE(("tty_input_read() status 0x%" B_PRIx32 "\n", status));
+
 	return *_length == 0 ? status : B_OK;
 }
 

src/add-ons/kernel/generic/tty/tty_private.h

@@ -128,6 +128,7 @@ struct tty_settings {
 struct tty {
 	int32				ref_count;	// referenced by cookies
 	int32				open_count;
+	int32				opened_count;
 	struct mutex		lock;
 	tty_settings		settings;
 	select_sync_pool*	select_pool;