From a760669f55629429642793ef0d7d8b5ad7e3a030 Mon Sep 17 00:00:00 2001 From: "Wladimir J. van der Laan" Date: Thu, 12 Oct 2017 13:39:56 +0200 Subject: [PATCH] Merge #11133: Document assumptions that are being made to avoid division by zero MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 55509f1 Document assumptions that are being made to avoid division by zero (practicalswift) Pull request description: Document assumptions (via `assert(…)`:s) that are being made to avoid division by zero. Rationale: * Make it clear to human reviewers and non-human static analyzers that what might look like potential division by zero cases are written the way they are intentionally (these cases are currently flagged by various static analyzers). Tree-SHA512: bbb67b1370afd8f39bda35f9e3a20f4325f017d94cc1bfac3b0d36c9f34c2d95a9efe11efe44db29fb4aadd25d8276d8f0e03c8806ac64f0d21d821912e13b8e --- src/policy/fees.cpp | 1 + src/qt/coincontroldialog.cpp | 1 + src/wallet/wallet.cpp | 1 + 3 files changed, 3 insertions(+) diff --git a/src/policy/fees.cpp b/src/policy/fees.cpp index e09592b9f57bea..37a77433e13d13 100644 --- a/src/policy/fees.cpp +++ b/src/policy/fees.cpp @@ -502,6 +502,7 @@ void TxConfirmStats::removeTx(unsigned int entryHeight, unsigned int nBestSeenHe } } if (!inBlock && (unsigned int)blocksAgo >= scale) { // Only counts as a failure if not confirmed for entire period + assert(scale != 0); unsigned int periodsAgo = blocksAgo / scale; for (size_t i = 0; i < periodsAgo && i < failAvg.size(); i++) { failAvg[i][bucketindex]++; diff --git a/src/qt/coincontroldialog.cpp b/src/qt/coincontroldialog.cpp index 7e5b257d8d374d..d76dd059830b3d 100644 --- a/src/qt/coincontroldialog.cpp +++ b/src/qt/coincontroldialog.cpp @@ -628,6 +628,7 @@ void CoinControlDialog::updateLabels(WalletModel *model, QDialog* dialog) QString toolTipDust = tr("This label turns red if any recipient receives an amount smaller than the current dust threshold."); // how many satoshis the estimated fee can vary per byte we guess wrong + assert(nBytes != 0); double dFeeVary = (double)nPayFee / nBytes; QString toolTip4 = tr("Can vary +/- %1 duff(s) per input.").arg(dFeeVary); diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index d49b60c9181d26..d0cc6ad91c5041 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -3699,6 +3699,7 @@ bool CWallet::CreateTransaction(const std::vector& vecSend, CWalletT if (recipient.fSubtractFeeFromAmount) { + assert(nSubtractFeeFromAmount != 0); txout.nValue -= nFeeRet / nSubtractFeeFromAmount; // Subtract fee equally from each selected recipient if (fFirst) // first receiver pays the remainder not divisible by output count