Custom Query (104 matches)

In NO_RTCM3_MAIN mode, space is allocated in the generated RINEX files for all possible data types. That causes much whitespace in the files. The attached patch implements a suggested enhancement to let the main program specify which data types to handle. If no data types are specified, the functionality is unchanged.

Tested with RINEX v. 2.

The RTCM RTK message time tags are time of week (GPS) and time of day (Glonass). When reading logged data offline, the 1013 message can be read to get full date for the RINEX header. The attached patch implements reading of the 1013 message in NO_RTCM3_MAIN mode. No change is made if NO_RTCM3_MAIN is undefined, and the header records created in rtcm3torinex.c are unchanged.

Bug report from Jun Shih (Jun.Shih@…)

=========== first message =================== I have seen the following ntrip server reset condition in my log: [02/Nov/2010:21:26:43] [22:Source Thread] add_chunk: hex [], read=21 [02/Nov/2010:21:26:43] [22:Source Thread] add_chunk: http chunk left=0 [02/Nov/2010:21:26:43] [22:Source Thread] DEBUG: Source received 0 bytes in try 2, total 0, errno: 0 [02/Nov/2010:21:26:43] [22:Source Thread] Didn't receive data from source after 800 milliseconds, assuming it died...

A bit debugging found that this caused by the "http chunk left=0" condition, the recv will return 0 because recv length parameter is zero (con->http_chunk->left - read_bytes =0) in source.c:663

len = recv(con->sock, con->food.source->chunk[con->food.source->cid].data + read_bytes, con->http_chunk->left - read_bytes, 0);

when len=0, subsequently maxread=0 as well. These cause the while loop to terminate on line 737 or 744. I believe this code is the same as 2.0.14.

=========== second message =================== But in my case connection is not shutdown (I can see from wireshark). Note that recv returns 0 if the length parameter is zero (which is not undocumented in the manual) and it does not return -1 in this case. I have attached a sample program to demonstrate that, to test “ telnet localhost 5000” and type some chars and a return from another terminal.

[jshih@ntriptest tcp_server]$ make tcp_recv cc tcp_recv.c -o tcp_recv [jshih@ntriptest tcp_server]$ ./tcp_recv

TCPServer Waiting for client on port 5000 got a connection from (127.0.0.1 , 43891)bytes_recieved 0 errno 0 bytes_recieved 0 errno 0 bytes_recieved 0 errno 0

I know my server is continuously sending but with inserted delay test. Further I changed the code to demonstrate that, there are data in the pipe in my case:

if (con->http_chunk->left < SOURCE_READSIZE) {

len = recv(con->sock, con->food.source->chunk[con->food.source->cid].data + read_bytes, con->http_chunk->left - read_bytes, 0); xa_debug (4, "Recv LEN1: recv left=%d read=%d len:%d errno:%d", con->http_chunk->left, read_bytes,len, errno);

if (len == 0)

{

len = recv(con->sock, con->food.source->chunk[con->food.source->cid].data + read_bytes, con->http_chunk->left - read_bytes+1, 0); xa_debug (4, "Recv LEN2: recv left=%d read=%d len:%d errno:%d", con->http_chunk->left, read_bytes,len, errno);

len = 0;

}

maxread = (int)(0.5 * con->http_chunk->left);

Below is the log capture:

[03/Nov/2010:15:53:08] [6:Source Thread] add_chunk: hex [], read=21

[03/Nov/2010:15:53:08] [6:Source Thread] add_chunk: http chunk left=0 [03/Nov/2010:15:53:08] [6:Source Thread] Recv LEN1: recv left=0 read=0 len:0 errno:0 [03/Nov/2010:15:53:08] [6:Source Thread] Recv LEN2: recv left=0 read=0 len:1 errno:0

As you can see if I immediately give a length parameter=1, I successfully recv’ed 1 byte. So there are data.

Also I made a change to source.c (see attached). I run for hours without connection drop (previously was dropping every a few minutes), please review the changes to see if this is a right solution.

changes in source.c =

736c736 < } else if (len == 0) { ---

} else if (len == 0 && con->http_chunk->left) {

744c744 < } while ((read_bytes < maxread) && (tries < source_read_tries)); ---

} while ((con->http_chunk->left==0

read_bytes < maxread) && (tries < source_read_tries));

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