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#include "args.hh"
#include "content-address.hh"
#include "split.hh"
namespace nix {
std::string FixedOutputHash::printMethodAlgo() const
{
return makeFileIngestionPrefix(method) + printHashType(hash.type);
}
std::string makeFileIngestionPrefix(FileIngestionMethod m)
{
switch (m) {
case FileIngestionMethod::Flat:
return "";
case FileIngestionMethod::Recursive:
return "r:";
default:
throw Error("impossible, caught both cases");
}
}
std::string ContentAddressMethod::renderPrefix() const
{
return std::visit(overloaded {
[](TextIngestionMethod) -> std::string { return "text:"; },
[](FileIngestionMethod m2) {
/* Not prefixed for back compat with things that couldn't produce text before. */
return makeFileIngestionPrefix(m2);
},
}, raw);
}
ContentAddressMethod ContentAddressMethod::parsePrefix(std::string_view & m)
{
ContentAddressMethod method = FileIngestionMethod::Flat;
if (splitPrefix(m, "r:"))
method = FileIngestionMethod::Recursive;
else if (splitPrefix(m, "text:"))
method = TextIngestionMethod {};
return method;
}
std::string ContentAddress::render() const
{
return std::visit(overloaded {
[](const TextHash & th) {
return "text:"
+ th.hash.to_string(Base32, true);
},
[](const FixedOutputHash & fsh) {
return "fixed:"
+ makeFileIngestionPrefix(fsh.method)
+ fsh.hash.to_string(Base32, true);
}
}, raw);
}
std::string ContentAddressMethod::render(HashType ht) const
{
return std::visit(overloaded {
[&](const TextIngestionMethod & th) {
return std::string{"text:"} + printHashType(ht);
},
[&](const FileIngestionMethod & fim) {
return "fixed:" + makeFileIngestionPrefix(fim) + printHashType(ht);
}
}, raw);
}
/**
* Parses content address strings up to the hash.
*/
static std::pair<ContentAddressMethod, HashType> parseContentAddressMethodPrefix(std::string_view & rest)
{
std::string_view wholeInput { rest };
std::string_view prefix;
{
auto optPrefix = splitPrefixTo(rest, ':');
if (!optPrefix)
throw UsageError("not a content address because it is not in the form '<prefix>:<rest>': %s", wholeInput);
prefix = *optPrefix;
}
auto parseHashType_ = [&](){
auto hashTypeRaw = splitPrefixTo(rest, ':');
if (!hashTypeRaw)
throw UsageError("content address hash must be in form '<algo>:<hash>', but found: %s", wholeInput);
HashType hashType = parseHashType(*hashTypeRaw);
return std::move(hashType);
};
// Switch on prefix
if (prefix == "text") {
// No parsing of the ingestion method, "text" only support flat.
HashType hashType = parseHashType_();
return {
TextIngestionMethod {},
std::move(hashType),
};
} else if (prefix == "fixed") {
// Parse method
auto method = FileIngestionMethod::Flat;
if (splitPrefix(rest, "r:"))
method = FileIngestionMethod::Recursive;
HashType hashType = parseHashType_();
return {
std::move(method),
std::move(hashType),
};
} else
throw UsageError("content address prefix '%s' is unrecognized. Recogonized prefixes are 'text' or 'fixed'", prefix);
}
ContentAddress ContentAddress::parse(std::string_view rawCa)
{
auto rest = rawCa;
auto [caMethod, hashType_] = parseContentAddressMethodPrefix(rest);
auto hashType = hashType_; // work around clang bug
return std::visit(overloaded {
[&](TextIngestionMethod &) {
return ContentAddress(TextHash {
.hash = Hash::parseNonSRIUnprefixed(rest, hashType)
});
},
[&](FileIngestionMethod & fim) {
return ContentAddress(FixedOutputHash {
.method = fim,
.hash = Hash::parseNonSRIUnprefixed(rest, hashType),
});
},
}, caMethod.raw);
}
std::pair<ContentAddressMethod, HashType> ContentAddressMethod::parse(std::string_view caMethod)
{
std::string asPrefix = std::string{caMethod} + ":";
// parseContentAddressMethodPrefix takes its argument by reference
std::string_view asPrefixView = asPrefix;
return parseContentAddressMethodPrefix(asPrefixView);
}
std::optional<ContentAddress> ContentAddress::parseOpt(std::string_view rawCaOpt)
{
return rawCaOpt == ""
? std::nullopt
: std::optional { ContentAddress::parse(rawCaOpt) };
};
std::string renderContentAddress(std::optional<ContentAddress> ca)
{
return ca ? ca->render() : "";
}
ContentAddress ContentAddress::fromParts(
ContentAddressMethod method, Hash hash) noexcept
{
return std::visit(overloaded {
[&](TextIngestionMethod _) -> ContentAddress {
return TextHash {
.hash = std::move(hash),
};
},
[&](FileIngestionMethod m2) -> ContentAddress {
return FixedOutputHash {
.method = std::move(m2),
.hash = std::move(hash),
};
},
}, method.raw);
}
ContentAddressMethod ContentAddress::getMethod() const
{
return std::visit(overloaded {
[](const TextHash & th) -> ContentAddressMethod {
return TextIngestionMethod {};
},
[](const FixedOutputHash & fsh) -> ContentAddressMethod {
return fsh.method;
},
}, raw);
}
const Hash & ContentAddress::getHash() const
{
return std::visit(overloaded {
[](const TextHash & th) -> auto & {
return th.hash;
},
[](const FixedOutputHash & fsh) -> auto & {
return fsh.hash;
},
}, raw);
}
std::string ContentAddress::printMethodAlgo() const
{
return getMethod().renderPrefix()
+ printHashType(getHash().type);
}
bool StoreReferences::empty() const
{
return !self && others.empty();
}
size_t StoreReferences::size() const
{
return (self ? 1 : 0) + others.size();
}
ContentAddressWithReferences ContentAddressWithReferences::withoutRefs(const ContentAddress & ca) noexcept
{
return std::visit(overloaded {
[&](const TextHash & h) -> ContentAddressWithReferences {
return TextInfo {
.hash = h,
.references = {},
};
},
[&](const FixedOutputHash & h) -> ContentAddressWithReferences {
return FixedOutputInfo {
.hash = h,
.references = {},
};
},
}, ca.raw);
}
ContentAddressWithReferences ContentAddressWithReferences::fromParts(
ContentAddressMethod method, Hash hash, StoreReferences refs)
{
return std::visit(overloaded {
[&](TextIngestionMethod _) -> ContentAddressWithReferences {
if (refs.self)
throw UsageError("Cannot have a self reference with text hashing scheme");
return TextInfo {
.hash = { .hash = std::move(hash) },
.references = std::move(refs.others),
};
},
[&](FileIngestionMethod m2) -> ContentAddressWithReferences {
return FixedOutputInfo {
.hash = {
.method = m2,
.hash = std::move(hash),
},
.references = std::move(refs),
};
},
}, method.raw);
}
ContentAddressMethod ContentAddressWithReferences::getMethod() const
{
return std::visit(overloaded {
[](const TextInfo & th) -> ContentAddressMethod {
return TextIngestionMethod {};
},
[](const FixedOutputInfo & fsh) -> ContentAddressMethod {
return fsh.hash.method;
},
}, raw);
}
Hash ContentAddressWithReferences::getHash() const
{
return std::visit(overloaded {
[](const TextInfo & th) {
return th.hash.hash;
},
[](const FixedOutputInfo & fsh) {
return fsh.hash.hash;
},
}, raw);
}
}
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