Merge #13216: [Qt] implements concept for different disk sizes on intro

9d0e52834 implements different disk sizes for different networks on intro (marcoagner)

Pull request description:

  Fixes https://github.com/bitcoin/bitcoin/issues/13213.
  Mostly, I layed out the concept to open the PR for refinement and getting feedback if the approach is okay. Changes are expected.

  Two points:
  - The values for both new consts `TESTNET_BLOCK_CHAIN_SIZE` and `TESTNET_CHAIN_STATE_SIZE` is certainly not optimal; I just checked the size of my testnet3 related dirs and set them to little bit higher values. Which values should be used?
  - Should we do something like this to regtest? Or these "niceties" do not matter when on regtest?

  Thanks!

Tree-SHA512: 8ae87a29fa8356b899e7a823c76cde793d9126b4ee59554d7a2a8edb088fe42a19976b34c06c2fd4a98a727e1e4971dd983f42b6093ea6caa255b45004e22bb4

6 files changed, 39 insertions, 11 deletions

diff --git a/src/chainparams.cpp b/src/chainparams.cpp
index d334233224..da4832dff8 100644
--- a/src/chainparams.cpp
+++ b/src/chainparams.cpp
@@ -107,6 +107,8 @@ public:
         pchMessageStart[3] = 0xd9;
         nDefaultPort = 8333;
         nPruneAfterHeight = 100000;
+        m_assumed_blockchain_size = 200;
+        m_assumed_chain_state_size = 3;
 
         genesis = CreateGenesisBlock(1231006505, 2083236893, 0x1d00ffff, 1, 50 * COIN);
         consensus.hashGenesisBlock = genesis.GetHash();
@@ -216,6 +218,8 @@ public:
         pchMessageStart[3] = 0x07;
         nDefaultPort = 18333;
         nPruneAfterHeight = 1000;
+        m_assumed_blockchain_size = 20;
+        m_assumed_chain_state_size = 2;
 
         genesis = CreateGenesisBlock(1296688602, 414098458, 0x1d00ffff, 1, 50 * COIN);
         consensus.hashGenesisBlock = genesis.GetHash();
@@ -305,6 +309,8 @@ public:
         pchMessageStart[3] = 0xda;
         nDefaultPort = 18444;
         nPruneAfterHeight = 1000;
+        m_assumed_blockchain_size = 0;
+        m_assumed_chain_state_size = 0;
 
         UpdateVersionBitsParametersFromArgs(args);
 
diff --git a/src/chainparams.h b/src/chainparams.h
index 19818b40af..6ff3dbb7e5 100644
--- a/src/chainparams.h
+++ b/src/chainparams.h
@@ -67,6 +67,10 @@ public:
     /** Policy: Filter transactions that do not match well-defined patterns */
     bool RequireStandard() const { return fRequireStandard; }
     uint64_t PruneAfterHeight() const { return nPruneAfterHeight; }
+    /** Minimum free space (in GB) needed for data directory */
+    uint64_t AssumedBlockchainSize() const { return m_assumed_blockchain_size; }
+    /** Minimum free space (in GB) needed for data directory when pruned; Does not include prune target*/
+    uint64_t AssumedChainStateSize() const { return m_assumed_chain_state_size; }
     /** Make miner stop after a block is found. In RPC, don't return until nGenProcLimit blocks are generated */
     bool MineBlocksOnDemand() const { return fMineBlocksOnDemand; }
     /** Return the BIP70 network string (main, test or regtest) */
@@ -87,6 +91,8 @@ protected:
     CMessageHeader::MessageStartChars pchMessageStart;
     int nDefaultPort;
     uint64_t nPruneAfterHeight;
+    uint64_t m_assumed_blockchain_size;
+    uint64_t m_assumed_chain_state_size;
     std::vector<std::string> vSeeds;
     std::vector<unsigned char> base58Prefixes[MAX_BASE58_TYPES];
     std::string bech32_hrp;
diff --git a/src/interfaces/node.cpp b/src/interfaces/node.cpp
index bd7e414ff3..acba05fd5e 100644
--- a/src/interfaces/node.cpp
+++ b/src/interfaces/node.cpp
@@ -60,6 +60,8 @@ public:
     bool softSetArg(const std::string& arg, const std::string& value) override { return gArgs.SoftSetArg(arg, value); }
     bool softSetBoolArg(const std::string& arg, bool value) override { return gArgs.SoftSetBoolArg(arg, value); }
     void selectParams(const std::string& network) override { SelectParams(network); }
+    uint64_t getAssumedBlockchainSize() override { return Params().AssumedBlockchainSize(); }
+    uint64_t getAssumedChainStateSize() override { return Params().AssumedChainStateSize(); }
     std::string getNetwork() override { return Params().NetworkIDString(); }
     void initLogging() override { InitLogging(); }
     void initParameterInteraction() override { InitParameterInteraction(); }
diff --git a/src/interfaces/node.h b/src/interfaces/node.h
index 1f8bbbff7a..7fa5958c51 100644
--- a/src/interfaces/node.h
+++ b/src/interfaces/node.h
@@ -52,6 +52,12 @@ public:
     //! Choose network parameters.
     virtual void selectParams(const std::string& network) = 0;
 
+    //! Get the (assumed) blockchain size.
+    virtual uint64_t getAssumedBlockchainSize() = 0;
+
+    //! Get the (assumed) chain state size.
+    virtual uint64_t getAssumedChainStateSize() = 0;
+
     //! Get network name.
     virtual std::string getNetwork() = 0;
 
diff --git a/src/qt/intro.cpp b/src/qt/intro.cpp
index 0b61b05318..a9a6ab9a8e 100644
--- a/src/qt/intro.cpp
+++ b/src/qt/intro.cpp
@@ -22,10 +22,6 @@
 #include <cmath>
 
 static const uint64_t GB_BYTES = 1000000000LL;
-/* Minimum free space (in GB) needed for data directory */
-constexpr uint64_t BLOCK_CHAIN_SIZE = 220;
-/* Minimum free space (in GB) needed for data directory when pruned; Does not include prune target */
-static const uint64_t CHAIN_STATE_SIZE = 3;
 /* Total required space (in GB) depending on user choice (prune, not prune) */
 static uint64_t requiredSpace;
 
@@ -114,11 +110,13 @@ void FreespaceChecker::check()
 }
 
 
-Intro::Intro(QWidget *parent) :
+Intro::Intro(QWidget *parent, uint64_t blockchain_size, uint64_t chain_state_size) :
     QDialog(parent),
     ui(new Ui::Intro),
     thread(0),
-    signalled(false)
+    signalled(false),
+    m_blockchain_size(blockchain_size),
+    m_chain_state_size(chain_state_size)
 {
     ui->setupUi(this);
     ui->welcomeLabel->setText(ui->welcomeLabel->text().arg(tr(PACKAGE_NAME)));
@@ -126,14 +124,14 @@ Intro::Intro(QWidget *parent) :
 
     ui->lblExplanation1->setText(ui->lblExplanation1->text()
         .arg(tr(PACKAGE_NAME))
-        .arg(BLOCK_CHAIN_SIZE)
+        .arg(m_blockchain_size)
         .arg(2009)
         .arg(tr("Bitcoin"))
     );
     ui->lblExplanation2->setText(ui->lblExplanation2->text().arg(tr(PACKAGE_NAME)));
 
     uint64_t pruneTarget = std::max<int64_t>(0, gArgs.GetArg("-prune", 0));
-    requiredSpace = BLOCK_CHAIN_SIZE;
+    requiredSpace = m_blockchain_size;
     QString storageRequiresMsg = tr("At least %1 GB of data will be stored in this directory, and it will grow over time.");
     if (pruneTarget) {
         uint64_t prunedGBs = std::ceil(pruneTarget * 1024 * 1024.0 / GB_BYTES);
@@ -145,7 +143,7 @@ Intro::Intro(QWidget *parent) :
     } else {
         ui->lblExplanation3->setVisible(false);
     }
-    requiredSpace += CHAIN_STATE_SIZE;
+    requiredSpace += m_chain_state_size;
     ui->sizeWarningLabel->setText(
         tr("%1 will download and store a copy of the Bitcoin block chain.").arg(tr(PACKAGE_NAME)) + " " +
         storageRequiresMsg.arg(requiredSpace) + " " +
@@ -201,8 +199,15 @@ bool Intro::pickDataDirectory(interfaces::Node& node)
 
     if(!fs::exists(GUIUtil::qstringToBoostPath(dataDir)) || gArgs.GetBoolArg("-choosedatadir", DEFAULT_CHOOSE_DATADIR) || settings.value("fReset", false).toBool() || gArgs.GetBoolArg("-resetguisettings", false))
     {
+        /* Use selectParams here to guarantee Params() can be used by node interface */
+        try {
+            node.selectParams(gArgs.GetChainName());
+        } catch (const std::exception&) {
+            return false;
+        }
+
         /* If current default data directory does not exist, let the user choose one */
-        Intro intro;
+        Intro intro(0, node.getAssumedBlockchainSize(), node.getAssumedChainStateSize());
         intro.setDataDirectory(dataDir);
         intro.setWindowIcon(QIcon(":icons/bitcoin"));
 
diff --git a/src/qt/intro.h b/src/qt/intro.h
index 2b3da963e2..01c4165f3e 100644
--- a/src/qt/intro.h
+++ b/src/qt/intro.h
@@ -30,7 +30,8 @@ class Intro : public QDialog
     Q_OBJECT
 
 public:
-    explicit Intro(QWidget *parent = 0);
+    explicit Intro(QWidget *parent = 0,
+                   uint64_t blockchain_size = 0, uint64_t chain_state_size = 0);
     ~Intro();
 
     QString getDataDirectory();
@@ -71,6 +72,8 @@ private:
     QMutex mutex;
     bool signalled;
     QString pathToCheck;
+    uint64_t m_blockchain_size;
+    uint64_t m_chain_state_size;
 
     void startThread();
     void checkPath(const QString &dataDir);