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* `nix-store --verify': revive checking the referrers table. This is

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important to get garbage collection to work if there is any
  inconsistency in the database (because the referrer table is used to
  determine whether it is safe to delete a path).
* `nix-store --verify': show some progress.
This commit is contained in:
Eelco Dolstra 2007-01-14 17:28:30 +00:00
parent 8f67b35886
commit 63f3ce6d9a
1 changed files with 60 additions and 46 deletions
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98
src/libstore/local-store.cc
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@ -722,6 +722,9 @@ void verifyStore(bool checkContents)
{
Transaction txn(nixDB);
printMsg(lvlInfo, "checking path existence");
Paths paths;
PathSet validPaths;
nixDB.enumTable(txn, dbValidPaths, paths);
@ -748,9 +751,12 @@ void verifyStore(bool checkContents)
}
}
/* "Usable" paths are those that are valid or have a
printMsg(lvlInfo, "checking path realisability");
/* "Realisable" paths are those that are valid or have a
substitute. */
PathSet usablePaths(validPaths);
PathSet realisablePaths(validPaths);
/* Check that the values of the substitute mappings are valid
paths. */
@ -759,47 +765,52 @@ void verifyStore(bool checkContents)
for (Paths::iterator i = subKeys.begin(); i != subKeys.end(); ++i) {
Substitutes subs = readSubstitutes(txn, *i);
if (!isStorePath(*i)) {
printMsg(lvlError, format("found substitutes for non-store path `%1%'") % *i);
printMsg(lvlError, format("removing substitutes for non-store path `%1%'") % *i);
nixDB.delPair(txn, dbSubstitutes, *i);
}
else if (subs.size() == 0)
nixDB.delPair(txn, dbSubstitutes, *i);
else
usablePaths.insert(*i);
realisablePaths.insert(*i);
}
/* Check the cleanup invariant: only usable paths can have
/* Check the cleanup invariant: only realisable paths can have
`references', `referrers', or `derivers' entries. */
/* Check the `derivers' table. */
printMsg(lvlInfo, "checking the derivers table");
Paths deriversKeys;
nixDB.enumTable(txn, dbDerivers, deriversKeys);
for (Paths::iterator i = deriversKeys.begin();
i != deriversKeys.end(); ++i)
{
if (usablePaths.find(*i) == usablePaths.end()) {
printMsg(lvlError, format("found deriver entry for unusable path `%1%'")
if (realisablePaths.find(*i) == realisablePaths.end()) {
printMsg(lvlError, format("removing deriver entry for unrealisable path `%1%'")
% *i);
nixDB.delPair(txn, dbDerivers, *i);
}
else {
Path deriver = queryDeriver(txn, *i);
if (!isStorePath(deriver)) {
printMsg(lvlError, format("found corrupt deriver `%1%' for `%2%'")
printMsg(lvlError, format("removing corrupt deriver `%1%' for `%2%'")
% deriver % *i);
nixDB.delPair(txn, dbDerivers, *i);
}
}
}
/* Check the `references' table. */
printMsg(lvlInfo, "checking the references table");
Paths referencesKeys;
nixDB.enumTable(txn, dbReferences, referencesKeys);
for (Paths::iterator i = referencesKeys.begin();
i != referencesKeys.end(); ++i)
{
if (usablePaths.find(*i) == usablePaths.end()) {
printMsg(lvlError, format("found references entry for unusable path `%1%'")
if (realisablePaths.find(*i) == realisablePaths.end()) {
printMsg(lvlError, format("removing references entry for unrealisable path `%1%'")
% *i);
setReferences(txn, *i, PathSet());
}
@ -812,7 +823,7 @@ void verifyStore(bool checkContents)
{
string dummy;
if (!nixDB.queryString(txn, dbReferrers, addPrefix(*j, *i), dummy)) {
printMsg(lvlError, format("missing referrer mapping from `%1%' to `%2%'")
printMsg(lvlError, format("adding missing referrer mapping from `%1%' to `%2%'")
% *j % *i);
nixDB.setString(txn, dbReferrers, addPrefix(*j, *i), "");
}
@ -824,44 +835,47 @@ void verifyStore(bool checkContents)
}
}
#if 0 // !!!
/* Check the `referrers' table. */
Paths referrersKeys;
nixDB.enumTable(txn, dbReferrers, referrersKeys);
for (Paths::iterator i = referrersKeys.begin();
i != referrersKeys.end(); ++i)
{
if (usablePaths.find(*i) == usablePaths.end()) {
printMsg(lvlError, format("found referrers entry for unusable path `%1%'")
% *i);
printMsg(lvlInfo, "checking the referrers table");
Strings referrers;
nixDB.enumTable(txn, dbReferrers, referrers);
for (Strings::iterator i = referrers.begin(); i != referrers.end(); ++i) {
/* Decode the entry (it's a tuple of paths). */
string::size_type nul = i->find((char) 0);
if (nul == string::npos) {
printMsg(lvlError, format("removing bad referrer table entry `%1%'") % *i);
nixDB.delPair(txn, dbReferrers, *i);
continue;
}
Path to(*i, 0, nul);
Path from(*i, nul + 1);
if (realisablePaths.find(to) == realisablePaths.end()) {
printMsg(lvlError, format("removing referrer entry from `%1%' to unrealisable `%2%'")
% from % to);
nixDB.delPair(txn, dbReferrers, *i);
}
else if (realisablePaths.find(from) == realisablePaths.end()) {
printMsg(lvlError, format("removing referrer entry from unrealisable `%1%' to `%2%'")
% from % to);
nixDB.delPair(txn, dbReferrers, *i);
}
else {
PathSet referrers, newReferrers;
queryReferrers(txn, *i, referrers);
for (PathSet::iterator j = referrers.begin();
j != referrers.end(); ++j)
{
Paths references;
if (usablePaths.find(*j) == usablePaths.end()) {
printMsg(lvlError, format("referrer mapping from `%1%' to unusable `%2%'")
% *i % *j);
} else {
nixDB.queryStrings(txn, dbReferences, *j, references);
if (find(references.begin(), references.end(), *i) == references.end()) {
printMsg(lvlError, format("missing reference mapping from `%1%' to `%2%'")
% *j % *i);
/* !!! repair by inserting *i into references */
}
else newReferrers.insert(*j);
PathSet references;
queryReferences(txn, from, references);
if (find(references.begin(), references.end(), to) == references.end()) {
printMsg(lvlError, format("adding missing referrer mapping from `%1%' to `%2%'")
% from % to);
references.insert(to);
setReferences(txn, from, references);
}
}
if (referrers != newReferrers)
nixDB.setStrings(txn, dbReferrers, *i,
Paths(newReferrers.begin(), newReferrers.end()));
}
}
#endif
txn.commit();
}