Greetings,
I am having trouble integrating LWIP into my embedded project due to my inability to observe the system without adversely affecting its ability to function within the platform. The intended target is an STM32F107 MCU + Micrel 8041 PHY running ChibiOS/RT. The TCP/IP functionality required is fairly light and consists of: 1) NTP or SNTP for time synchronization. 2) HTTP client for data payload delivery.
I am still in the midst of locking down the driver code for the MAC and other RTOS configuration issues which can affect LWIP (e.g. debug code), so I would like to decouple development from the hardware for a moment and get these functions to work with just LWI, then introduce the working LWIP apps with more confidence into the resource constrained RTOS environment. The lwip-contrib version 1.4.1 has a unix port called
unixsim which is what I have attempted to use but without much success in my native environment. The README sort of describes how to make for Linux or FreeBSD (with kernel recompile), though my host is Mac OS X 10.7.5 with
tuntap because my Ubuntu VM had failed to compile and I did not feel like digging out FreeBSD for this task. With a little fiddling I was able to get it to compile on OS X, though the program exits before I can tcpdump the tap0 or otherwise probe it. I am not sure why it does this. Here is the typical output with all the debug output options enabled from a gdb session:
(gdb) file simhost
Reading symbols for shared libraries ... done
Reading symbols from /STM32/Work/lwip-1.4.1/contrib/ports/unix/proj/unixsim/simhost...done.
(gdb) run -d
Starting program: /STM32/Work/lwip-1.4.1/contrib/ports/unix/proj/unixsim/simhost -d
Reading symbols for shared libraries ++.......................... done
Host at 192.168.1.20 mask 255.255.255.0 gateway 192.168.1.1
System initialized.
netif initializing...
netif initialized.
TCP/IP initializing...
netif_set_ipaddr: netif address being changed
netif: IP address of interface set to 192.168.1.20
netif: netmask of interface set to 255.255.255.0
netif: GW address of interface set to 192.168.1.1
tapif_init: fd 3
tapif_init: system("/sbin/ifconfig tap0 inet 192.168.1.1 up");
netif: added interface tp IP addr 192.168.1.20 netmask 255.255.255.0 gw 192.168.1.1
netif: setting default interface tp
tcp_bind: bind to port 80
pbuf_alloc(length=42)
pbuf_alloc: allocated pbuf 0x100044c10
pbuf_alloc(length=42) == 0x100044c10
pbuf_alloc(length=42)
pbuf_alloc: allocated pbuf 0x100044b78
pbuf_alloc(length=42) == 0x100044b78
TCP/IP initialized.
Applications started.
tcpip_thread: PACKET 0x100040180
pbuf_free(0x100044c10)
pbuf_free: deallocating 0x100044c10
tcpip_thread: PACKET 0x100040158
pbuf_free(0x100044b78)
pbuf_free: deallocating 0x100044b78
tcpip_thread: API message 0x100586dc8
tcpip_thread: API message 0x100609de8
tcpip_thread: API message 0x10068bdf8
tcpip_thread: API message 0x100586df8
tcp_bind: bind to port 7
tcpip_thread: API message 0x100609e18
tcp_bind: bind to port 23
tcpip_thread: API message 0x100586e08
tcpip_thread: API message 0x100609e28
tcpip_thread: API message 0x10068be28
udp_bind(ipaddr = 0.0.0.0, port = 7)
udp_bind: bound to 0.0.0.0, port 7
Program exited normally.
(1) Any hints for porting to OS X would be greatly appreciated. For instance, what does the above log indicate?
(2) I was able to get it to work on the Ubuntu VM after learning a bit more about the project through my botched Darwin port. These notes may be of interest to whomever writes the readme files for lwip-contrib's unixsim project:
make ARCH=linux
Removed -Werror due to Warning the comparison will always evaluate to true and set variables unused
LDFLAGS from -lpthread to -pthread
The make ARCH=linux appears to be optional on my Ubuntu VM and seemingly introduces more warnings than without specifying ARCH (which defaults to unix, IIRC).
(3) Is there a simpler or easier way to develop an embedded TCP/IP application than the path I am on?