Clean up Windows event handles on com port close

This avoids having to wait for the receiver to timeout before we can
open the same com port again.

This patch also adds a bit more debugging -- it prints Windows error
messages to stdout along with the file/line where the error was generated.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/altosui/libaltos/libaltos.c b/altosui/libaltos/libaltos.c
index 515432f9ac21f8ed4e351ae89a881ae59cc398fe..ab6ca87887c87b69675890e8f87f6e55afb4d4bf 100644 (file)
--- a/altosui/libaltos/libaltos.c
+++ b/altosui/libaltos/libaltos.c
@@ -941,7 +941,7 @@ struct altos_file {
 };
 
 static void
-altos_set_last_windows_error(void)
+_altos_set_last_windows_error(char *file, int line)
 {
        DWORD   error = GetLastError();
        TCHAR   message[1024];
@@ -952,9 +952,13 @@ altos_set_last_windows_error(void)
                      message,
                      sizeof (message) / sizeof (TCHAR),
                      NULL);
+       if (error != ERROR_SUCCESS)
+               printf ("%s:%d %s\n", file, line, message);
        altos_set_last_error(error, message);
 }
 
+#define altos_set_last_windows_error() _altos_set_last_windows_error(__FILE__, __LINE__)
+
 PUBLIC struct altos_list *
 altos_list_start(void)
 {
@@ -1161,6 +1165,7 @@ altos_flush(struct altos_file *file)
                if (!WriteFile(file->handle, data, used, &put, &file->ov_write)) {
                        if (GetLastError() != ERROR_IO_PENDING) {
                                altos_set_last_windows_error();
+                               printf ("\tflush write error\n");
                                return LIBALTOS_ERROR;
                        }
                        ret = WaitForSingleObject(file->ov_write.hEvent, INFINITE);
@@ -1168,11 +1173,13 @@ altos_flush(struct altos_file *file)
                        case WAIT_OBJECT_0:
                                if (!GetOverlappedResult(file->handle, &file->ov_write, &put, FALSE)) {
                                        altos_set_last_windows_error();
+                                       printf ("\tflush result error\n");
                                        return LIBALTOS_ERROR;
                                }
                                break;
                        default:
                                altos_set_last_windows_error();
+                               printf ("\tflush wait error\n");
                                return LIBALTOS_ERROR;
                        }
                }
@@ -1188,7 +1195,6 @@ altos_open(struct altos_device *device)
 {
        struct altos_file       *file = calloc (1, sizeof (struct altos_file));
        char    full_name[64];
-       DCB dcbSerialParams = {0};
        COMMTIMEOUTS timeouts;
 
        if (!file)
@@ -1201,6 +1207,7 @@ altos_open(struct altos_device *device)
                                  FILE_FLAG_OVERLAPPED, NULL);
        if (file->handle == INVALID_HANDLE_VALUE) {
                altos_set_last_windows_error();
+               printf ("cannot open %s\n", full_name);
                free(file);
                return NULL;
        }
@@ -1214,24 +1221,6 @@ altos_open(struct altos_device *device)
        timeouts.WriteTotalTimeoutConstant = 0;
        SetCommTimeouts(file->handle, &timeouts);
 
-       dcbSerialParams.DCBlength = sizeof(dcbSerialParams);
-       if (!GetCommState(file->handle, &dcbSerialParams)) {
-               altos_set_last_windows_error();
-               CloseHandle(file->handle);
-               free(file);
-               return NULL;
-       }
-       dcbSerialParams.BaudRate = CBR_9600;
-       dcbSerialParams.ByteSize = 8;
-       dcbSerialParams.StopBits = ONESTOPBIT;
-       dcbSerialParams.Parity = NOPARITY;
-       if (!SetCommState(file->handle, &dcbSerialParams)) {
-               altos_set_last_windows_error();
-               CloseHandle(file->handle);
-               free(file);
-               return NULL;
-       }
-
        return file;
 }
 
@@ -1241,6 +1230,10 @@ altos_close(struct altos_file *file)
        if (file->handle != INVALID_HANDLE_VALUE) {
                CloseHandle(file->handle);
                file->handle = INVALID_HANDLE_VALUE;
+               SetEvent(file->ov_read.hEvent);
+               SetEvent(file->ov_write.hEvent);
+               CloseHandle(file->ov_read.hEvent);
+               CloseHandle(file->ov_write.hEvent);
        }
 }