nx_transport_policy_gate.nx source

1// nx_transport_policy_gate.nx -- gate for the TIERED TRANSPORT policy (best-of-June-2026 on top, 2// skilled fallbacks, mandatory failure flagging, auto-heal). KATs the whole life-cycle: 3// T1 best-tier selection per capability mask (QUIC>striped>single; nothing->0 hard-down) 4// T2 skilled fallback: failures below threshold KEEP the tier (no flap); the 3rd consecutive 5// failure falls ONE rung (T1->T2->T3, clamped) 6// T3 success resets the failure counter (one blip never accumulates into a fallback) 7// T4 auto-heal: upgrade probe allowed only after the backoff window; backoff DOUBLES per 8// fallback (30->60) and caps; a successful upgrade HALVES it (healing accelerates) 9// T5 flag line: every transition assembles the mandatory TRANSPORT-TIER line (FAIL-DOWN 10// verdict=DEGRADED / HEAL-UP verdict=GREEN) -- parse-checked byte content 11// T6 NEG: no upgrade before the window; T7 NEG: tier never falls below SINGLE. 12// expect_exit: 0 license_tier: ORIGINAL 13import "nx_transport_policy.nx" 14 15func pw2(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} sys_write(1,s,n); return 0 } 16func pn2(v: i64) -> i64 { 17 let b: *u8=sys_mmap(28); var m: i64=v; if m<0{sys_write(1,"-" as *u8,1);m=0-m} 18 let t: *u8=sys_mmap(28); var k: i64=0; if m==0{t[0]=48 as u8;k=1} while m>0{t[k]=(48+(m%10)) as u8;m=m/10;k=k+1} 19 var i: i64=0; while i<k{b[i]=t[k-1-i];i=i+1} sys_write(1,b,k); return 0 } 20func contains2(hay: *u8, n: i64, needle: *u8) -> i64 { 21 var nl: i64=0; while needle[nl]!=(0 as u8){nl=nl+1} 22 if nl==0 {return 1} 23 var i: i64=0 24 while i+nl<=n { var j: i64=0; var ok: i64=1; while j<nl { if hay[i+j]!=needle[j]{ok=0;j=nl} else {j=j+1} } if ok==1{return 1} i=i+1 } 25 return 0 } 26func chk2(name: *u8, ok: i64, pass: *i64) -> i64 { 27 pw2(" " as *u8) 28 if ok==1 { pw2("PASS " as *u8); pass[0]=pass[0]+1 } else { pw2("FAIL " as *u8) } 29 pw2(name); pw2("\n" as *u8) 30 return 0 } 31 32func main() -> i64 { 33 pw2("=== nx_transport_policy_gate: tier ladder + skilled fallback + flag + auto-heal ===\n" as *u8) 34 let pass: *i64 = sys_mmap(16) as *i64 35 pass[0]=0 36 37 // T1 best-tier per caps 38 var t1: i64 = 1 39 if tp_best(7) != 1 { t1 = 0 } // QUIC up -> top 40 if tp_best(3) != 2 { t1 = 0 } // no QUIC, multi-leg ok -> striped 41 if tp_best(1) != 3 { t1 = 0 } // only single WSS -> single 42 if tp_best(0) != 0 { t1 = 0 } // nothing -> hard-down 0 43 chk2("T1 best-tier selection per capability mask " as *u8, t1, pass) 44 45 // T2 skilled fallback at threshold, not before 46 let st: *i64 = sys_mmap(32) as *i64 47 st[0]=0; st[1]=0; st[2]=0 48 var tier: i64 = 1 49 var t2: i64 = 1 50 tier = tp_on_failure(tier, 1000, st) 51 if tier != 1 { t2 = 0 } // 1st failure: stay 52 tier = tp_on_failure(tier, 1010, st) 53 if tier != 1 { t2 = 0 } // 2nd: stay 54 tier = tp_on_failure(tier, 1020, st) 55 if tier != 2 { t2 = 0 } // 3rd: fall to striped 56 chk2("T2 fallback only on 3rd consecutive failure " as *u8, t2, pass) 57 58 // T3 success resets the counter 59 st[0]=2 60 tp_on_success(st) 61 var t3: i64 = 1 62 if st[0] != 0 { t3 = 0 } 63 chk2("T3 success heartbeat resets the failure counter " as *u8, t3, pass) 64 65 // T4 heal window + backoff doubling + upgrade halving 66 var t4: i64 = 1 67 if st[2] != 30 { t4 = 0 } // first fallback set 30s 68 if tp_should_retry_upgrade(2, 1025, st) != 0 { t4 = 0 } // 5s later: window closed 69 if tp_should_retry_upgrade(2, 1055, st) != 1 { t4 = 0 } // 35s later: window open 70 var tafter: i64 = tier 71 tafter = tp_on_failure(tafter, 2000, st) 72 tafter = tp_on_failure(tafter, 2010, st) 73 tafter = tp_on_failure(tafter, 2020, st) // threshold again -> falls to 3, backoff doubles 74 if tafter != 3 { t4 = 0 } 75 if st[2] != 60 { t4 = 0 } 76 let up: i64 = tp_on_upgrade(tafter, st) // heal probe succeeded -> back to 2, backoff halves 77 if up != 2 { t4 = 0 } 78 if st[2] != 30 { t4 = 0 } 79 chk2("T4 heal window + backoff x2 on fall, /2 on heal " as *u8, t4, pass) 80 81 // T5 flag lines (mandatory, parse-checked) 82 let buf: *u8 = sys_mmap(256) 83 var n: i64 = tp_flag(buf, 3000, 1, 2, 1) 84 var t5: i64 = 1 85 if contains2(buf, n, "TRANSPORT-TIER epoch=3000 from=1 to=2 event=FAIL-DOWN verdict=DEGRADED" as *u8) != 1 { t5 = 0 } 86 n = tp_flag(buf, 3100, 2, 1, 2) 87 if contains2(buf, n, "event=HEAL-UP verdict=GREEN" as *u8) != 1 { t5 = 0 } 88 chk2("T5 mandatory flag lines assemble byte-correct " as *u8, t5, pass) 89 90 // T6 NEG: no upgrade before the window 91 st[1]=5000; st[2]=30 92 var t6: i64 = 0 93 if tp_should_retry_upgrade(2, 5010, st) == 0 { t6 = 1 } 94 chk2("T6 NEG no premature upgrade (window closed) " as *u8, t6, pass) 95 96 // T7 NEG: never below SINGLE 97 st[0]=2 98 let t7t: i64 = tp_on_failure(3, 6000, st) 99 var t7: i64 = 0 100 if t7t == 3 { t7 = 1 } 101 chk2("T7 NEG tier clamps at SINGLE (never disconnects) " as *u8, t7, pass) 102 103 pw2("TRANSPORT-POLICY-GATE pass=" as *u8); pn2(pass[0]); pw2("/7" as *u8) 104 if pass[0]==7 { pw2(" verdict=GREEN -- top-of-line first, skilled fallbacks, flagged + self-healing\n" as *u8); return 0 } 105 pw2(" verdict=RED\n" as *u8) 106 return 1 107}