Fixed a bug with a 2048-sized transfer from modem

As the circular buffer is used to hold the incoming data from the modem,
its free size must be one byte less than is actually available or we'll get
readp == writep and the buffer will be considered empty.

diff --git a/src/gsm0710muxd.c b/src/gsm0710muxd.c
index bb49d733bc5dccc6088f3aaafff876686e70f811..0b9e7ad4870e49b5b1be43d473f0cf7c38001b7f 100644 (file)
--- a/src/gsm0710muxd.c
+++ b/src/gsm0710muxd.c
@@ -194,7 +194,7 @@ typedef struct Serial
  * tells how much free space there is in the buffer
  */
 //int gsm0710_buffer_free(GSM0710_Buffer *buf);
-#define gsm0710_buffer_free(buf) ((buf->readp > buf->writep) ? (buf->readp - buf->writep) : (GSM0710_BUFFER_SIZE - (buf->writep-buf->readp)))
+#define gsm0710_buffer_free(buf) ((buf->readp > buf->writep) ? (buf->readp - buf->writep) : (GSM0710_BUFFER_SIZE - (buf->writep-buf->readp)) - 1)
 
 ////////////////////////////////// constants & globals
 static unsigned char close_channel_cmd[] = { GSM0710_CONTROL_CLD | GSM0710_CR, GSM0710_EA | (0 << 1) };