From 2a97af80db8e82d77e1d40968f39774319e23868 Mon Sep 17 00:00:00 2001
From: Cameron Garnham <da2ce7@gmail.com>
Date: Tue, 4 Apr 2017 11:38:38 +0200
Subject: [PATCH 1/3] Refactor Code-Example with Better Formatting

No-need to calculate the GetMedianTimePast() value twice.
---
 bip-0148.mediawiki | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/bip-0148.mediawiki b/bip-0148.mediawiki
index 13ad4cdc..5accfcf2 100644
--- a/bip-0148.mediawiki
+++ b/bip-0148.mediawiki
@@ -38,13 +38,14 @@ While this BIP is active, all blocks must set the nVersion header top 3 bits to
 
 <pre>
 // BIP148 mandatory segwit signalling.
-if (pindex->GetMedianTimePast() >= 1501545600 && // Tue 1 Aug 2017 00:00:00 UTC
-    pindex->GetMedianTimePast() <= 1510704000 && // Wed 15 Nov 2017 00:00:00 UTC
-    !IsWitnessEnabled(pindex->pprev, chainparams.GetConsensus()))
+int64_t nMedianTimePast = pindex->GetMedianTimePast();
+if ( (nMedianTimePast >= 1501545600) &&  // Tue 01 Aug 2017 00:00:00 UTC
+     (nMedianTimePast <= 1510704000) &&  // Wed 15 Nov 2017 00:00:00 UTC
+     (!IsWitnessEnabled(pindex->pprev, chainparams.GetConsensus())) )  // Segwit is not active
 {
-    // versionbits topbit and segwit flag must be set.
-    if ((pindex->nVersion & VERSIONBITS_TOP_MASK) != VERSIONBITS_TOP_BITS ||
-        (pindex->nVersion & VersionBitsMask(chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGWIT)) == 0) {
+    bool fVersionBits = (pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS; // BIP9 bit set
+    bool fSegbit = (pindex->nVersion & VersionBitsMask(chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGWIT)) != 0; // segwit bit set
+    if (!(fVersionBits && fSegbit)) {
         return state.DoS(0, error("ConnectBlock(): relayed block must signal for segwit, please upgrade"), REJECT_INVALID, "bad-no-segwit");
     }
 }

From 1352c367a1431fef1a711edeb239fa822a564c4b Mon Sep 17 00:00:00 2001
From: Cameron Garnham <da2ce7@gmail.com>
Date: Tue, 4 Apr 2017 12:30:31 +0200
Subject: [PATCH 2/3] Stop BIP 148 enforced signalling if SegWit is Locked-In
 State

---
 bip-0148.mediawiki | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/bip-0148.mediawiki b/bip-0148.mediawiki
index 5accfcf2..6eb9c42f 100644
--- a/bip-0148.mediawiki
+++ b/bip-0148.mediawiki
@@ -37,14 +37,22 @@ While this BIP is active, all blocks must set the nVersion header top 3 bits to
 === Reference implementation ===
 
 <pre>
+// Check if Segregated Witness is Locked In
+bool IsWitnessLockedIn(const CBlockIndex* pindexPrev, const Consensus::Params& params)
+{
+    LOCK(cs_main);
+    return (VersionBitsState(pindexPrev, params, Consensus::DEPLOYMENT_SEGWIT, versionbitscache) == THRESHOLD_LOCKED_IN);
+}
+
 // BIP148 mandatory segwit signalling.
 int64_t nMedianTimePast = pindex->GetMedianTimePast();
 if ( (nMedianTimePast >= 1501545600) &&  // Tue 01 Aug 2017 00:00:00 UTC
      (nMedianTimePast <= 1510704000) &&  // Wed 15 Nov 2017 00:00:00 UTC
-     (!IsWitnessEnabled(pindex->pprev, chainparams.GetConsensus())) )  // Segwit is not active
+     (!IsWitnessLockedIn(pindex->pprev, chainparams.GetConsensus()) &&  // Segwit is not locked in
+      !IsWitnessEnabled(pindex->pprev, chainparams.GetConsensus())) )   // and is not active.
 {
-    bool fVersionBits = (pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS; // BIP9 bit set
-    bool fSegbit = (pindex->nVersion & VersionBitsMask(chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGWIT)) != 0; // segwit bit set
+    bool fVersionBits = (pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS;
+    bool fSegbit = (pindex->nVersion & VersionBitsMask(chainparams.GetConsensus(), Consensus::DEPLOYMENT_SEGWIT)) != 0;
     if (!(fVersionBits && fSegbit)) {
         return state.DoS(0, error("ConnectBlock(): relayed block must signal for segwit, please upgrade"), REJECT_INVALID, "bad-no-segwit");
     }

From 5f34ed741a68cb4e2aaf0343d6a4ad5f3119a3d2 Mon Sep 17 00:00:00 2001
From: Cameron Garnham <da2ce7@gmail.com>
Date: Tue, 4 Apr 2017 12:55:33 +0200
Subject: [PATCH 3/3] update BIP text for locked-in state

---
 bip-0148.mediawiki | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bip-0148.mediawiki b/bip-0148.mediawiki
index 6eb9c42f..4dca9d76 100644
--- a/bip-0148.mediawiki
+++ b/bip-0148.mediawiki
@@ -30,7 +30,7 @@ It is hoped that miners will respond to this BIP by activating segwit early, bef
 
 All times are specified according to median past time.
 
-This BIP will be activate between midnight August 1st 2017 (epoch time 1501545600) and midnight November 15th 2017 (epoch time 1510704000) if the existing segwit deployment is not activated before epoch time 1501545600. This BIP will cease to be active when the existing segwit deployment activates.
+This BIP will be active between midnight August 1st 2017 (epoch time 1501545600) and midnight November 15th 2017 (epoch time 1510704000) if the existing segwit deployment is not locked-in or activated before epoch time 1501545600. This BIP will cease to be active when segwit is locked-in.
 
 While this BIP is active, all blocks must set the nVersion header top 3 bits to 001 together with bit field (1<<1) (according to the existing segwit deployment). Blocks that do not signal as required will be rejected.