stp_in() propagated the TC flag of any BPDU that did not arrive on an
alternate port, and acknowledged and propagated a TCN from any port, so a
port still in its listen period or held discarding in a dispute could flush
the addresses of every other port and move the topology change counter.
802.1D-2004 17.31 keeps the Topology Change machine in LEARNING until the
port forwards and drops rcvdTc and rcvdTcn there. Both paths now ask for
the forwarding state first; an alternate port is discarding, so the old
check is covered by the new one.
Scenario 53 plays a TC flag and a TCN into a port that is still discarding,
and then into the same port once it forwards. Scenario 51 used a TCN on a
port one tick short of its edge transition as the trigger for the clock it
tests; it now waits for the transition.
The frame the simulator builds carries a vlan_tag between the RTL tag and the BPDU, but left its TPID zero. stp_in() now takes the body offset from TRAP_RX_BODY(), which reads those two bytes, so it took the untagged branch and parsed the body four bytes early. Writing 0x8100 makes the frame what its layout says it is.
Reception moved to the RMA trap in main, so rtl837x_stp.c calls trap_rma_set() from stp_setup() and stp_off(). The simulator defines neither, so it does not link. Linking rtl837x_trap.c instead would pull trap_init() and the register primitives it needs, which the simulator does not mock.
stp_sim.c declared variables in the middle of the scenarios and put
whole loops and conditions on one line. Each block now starts with its
declarations; an initializer that depends on what happens before it
stays where it was as an assignment. Bodies of if and for are on lines
of their own, functions are separated by an empty line, and lines stay
within 120 columns. The output of stp_sim -v is unchanged.
Scenarios 4 and 7 start from the state scenario 3 leaves behind, and 38
from the one 37 leaves, and they called those scenarios for it, so the
headings of 3 and 37 showed up again in the middle of the run. The setup
of 3 and 37 now lives in functions of its own that the scenarios call.
test/stp/shim held hand-written copies of the headers the STP code
includes, and they had drifted: the uIP buffer was 600 bytes instead of
1556, struct machine had three fields, port_ingress_filter_get()
returned a plain uint8_t. The simulator now compiles rtl837x_stp.c and
rtl837x_stp_cli.c the way test/ compiles firmware sources, with the real
headers and sdcc_shim.h forced in, and with the same warnings, including
-Wno-pointer-sign for the string literals passed to cmd_compare(). It
stays on -std=c11: in gnu11 mode glibc defines LITTLE_ENDIAN, which
uip-conf.h names as the byte order, and HTONS() stops swapping. Its own
print_string() and cmd_compare() take the firmware's argument types.
* stp: select the root port by cost and block redundant links
* stp: move the protocol to BANK4 and keep the command line in BANK2
* stp: implement the RSTP state machines of 802.1D-2004 clause 17
* stp: counters, more settings and a fuller Spanning Tree page
* stp: make a link aggregation group one port of the RSTP tree
* web: serve the Spanning Tree JSON from BANK4 as well
Kept in BANK1, the larger Spanning Tree page would leave under 1 kB
there for the rest of the web server and every page still to come, so
send_stp() and send_stp_counters() move to httpd/page_stp.c in BANK4
with the protocol, as banked calls, with their own copies of the few output
helpers and of the JSON header, so nothing in BANK4 calls into BANK1
directly or hands it a pointer into its code space. BANK4 takes the
free flash between BANK3 and the web files.
KP_9000_6XHML_X2: BANK1 44336, BANK2 36969, BANK3 11942, BANK4 20965
bytes of 49152.
d00f