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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(const FileIngestionMethod m)
{
switch (m) {
case FileIngestionMethod::Flat:
return "";
case FileIngestionMethod::Recursive:
return "r:";
default:
throw Error("impossible, caught both cases");
}
}
std::string makeFixedOutputCA(FileIngestionMethod method, const Hash & hash)
{
return "fixed:"
+ makeFileIngestionPrefix(method)
+ hash.to_string(Base32, true);
}
std::string renderContentAddress(ContentAddress ca)
{
return std::visit(overloaded {
[](TextHash & th) {
return "text:" + th.hash.to_string(Base32, true);
},
[](FixedOutputHash & fsh) {
return makeFixedOutputCA(fsh.method, fsh.hash);
}
}, ca);
}
std::string renderContentAddressMethod(ContentAddressMethod cam)
{
return std::visit(overloaded {
[](TextHashMethod & th) {
return std::string{"text:"} + printHashType(htSHA256);
},
[](FixedOutputHashMethod & fshm) {
return "fixed:" + makeFileIngestionPrefix(fshm.fileIngestionMethod) + printHashType(fshm.hashType);
}
}, cam);
}
/*
Parses content address strings up to the hash.
*/
static ContentAddressMethod 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_();
if (hashType != htSHA256)
throw Error("text content address hash should use %s, but instead uses %s",
printHashType(htSHA256), printHashType(hashType));
return TextHashMethod {};
} else if (prefix == "fixed") {
// Parse method
auto method = FileIngestionMethod::Flat;
if (splitPrefix(rest, "r:"))
method = FileIngestionMethod::Recursive;
HashType hashType = parseHashType_();
return FixedOutputHashMethod {
.fileIngestionMethod = method,
.hashType = std::move(hashType),
};
} else
throw UsageError("content address prefix '%s' is unrecognized. Recogonized prefixes are 'text' or 'fixed'", prefix);
}
ContentAddress parseContentAddress(std::string_view rawCa) {
auto rest = rawCa;
ContentAddressMethod caMethod = parseContentAddressMethodPrefix(rest);
return std::visit(
overloaded {
[&](TextHashMethod & thm) {
return ContentAddress(TextHash {
.hash = Hash::parseNonSRIUnprefixed(rest, htSHA256)
});
},
[&](FixedOutputHashMethod & fohMethod) {
return ContentAddress(FixedOutputHash {
.method = fohMethod.fileIngestionMethod,
.hash = Hash::parseNonSRIUnprefixed(rest, std::move(fohMethod.hashType)),
});
},
}, caMethod);
}
ContentAddressMethod parseContentAddressMethod(std::string_view caMethod)
{
std::string_view asPrefix {std::string{caMethod} + ":"};
return parseContentAddressMethodPrefix(asPrefix);
}
std::optional<ContentAddress> parseContentAddressOpt(std::string_view rawCaOpt)
{
return rawCaOpt == "" ? std::optional<ContentAddress>() : parseContentAddress(rawCaOpt);
};
std::string renderContentAddress(std::optional<ContentAddress> ca)
{
return ca ? renderContentAddress(*ca) : "";
}
Hash getContentAddressHash(const ContentAddress & ca)
{
return std::visit(overloaded {
[](const TextHash & th) {
return th.hash;
},
[](const FixedOutputHash & fsh) {
return fsh.hash;
}
}, ca);
}
}
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