lix/src/libstore/store-api.cc

#include "store-api.hh"
#include "globals.hh"
#include "util.hh"


namespace nix {


bool StoreAPI::hasSubstitutes(const Path & path)
{
    return !querySubstitutes(path).empty();
}


bool isInStore(const Path & path)
{
    return path[0] == '/'
        && string(path, 0, nixStore.size()) == nixStore
        && path.size() >= nixStore.size() + 2
        && path[nixStore.size()] == '/';
}


bool isStorePath(const Path & path)
{
    return isInStore(path)
        && path.find('/', nixStore.size() + 1) == Path::npos;
}


void assertStorePath(const Path & path)
{
    if (!isStorePath(path))
        throw Error(format("path `%1%' is not in the Nix store") % path);
}


Path toStorePath(const Path & path)
{
    if (!isInStore(path))
        throw Error(format("path `%1%' is not in the Nix store") % path);
    Path::size_type slash = path.find('/', nixStore.size() + 1);
    if (slash == Path::npos)
        return path;
    else
        return Path(path, 0, slash);
}


void checkStoreName(const string & name)
{
    string validChars = "+-._?=";
    /* Disallow names starting with a dot for possible security
       reasons (e.g., "." and ".."). */
    if (string(name, 0, 1) == ".")
        throw Error(format("illegal name: `%1%'") % name);
    for (string::const_iterator i = name.begin(); i != name.end(); ++i)
        if (!((*i >= 'A' && *i <= 'Z') ||
              (*i >= 'a' && *i <= 'z') ||
              (*i >= '0' && *i <= '9') ||
              validChars.find(*i) != string::npos))
        {
            throw Error(format("invalid character `%1%' in name `%2%'")
                % *i % name);
        }
}


Path makeStorePath(const string & type,
    const Hash & hash, const string & suffix)
{
    /* e.g., "source:sha256:1abc...:/nix/store:foo.tar.gz" */
    string s = type + ":sha256:" + printHash(hash) + ":"
        + nixStore + ":" + suffix;

    checkStoreName(suffix);

    return nixStore + "/"
        + printHash32(compressHash(hashString(htSHA256, s), 20))
        + "-" + suffix;
}


Path makeFixedOutputPath(bool recursive,
    string hashAlgo, Hash hash, string name)
{
    /* !!! copy/paste from primops.cc */
    Hash h = hashString(htSHA256, "fixed:out:"
        + (recursive ? (string) "r:" : "") + hashAlgo + ":"
        + printHash(hash) + ":"
        + "");
    return makeStorePath("output:out", h, name);
}


std::pair<Path, Hash> computeStorePathForPath(const Path & srcPath,
    bool fixed, bool recursive, string hashAlgo)
{
    Hash h(htSHA256);
    {
        SwitchToOriginalUser sw;
        h = hashPath(htSHA256, srcPath);
    }

    string baseName = baseNameOf(srcPath);

    Path dstPath;
    
    if (fixed) {

        HashType ht(parseHashType(hashAlgo));
        Hash h2(ht);
        {
            SwitchToOriginalUser sw;
            h2 = recursive ? hashPath(ht, srcPath) : hashFile(ht, srcPath);
        }
        
        dstPath = makeFixedOutputPath(recursive, hashAlgo, h2, baseName);
    }
        
    else dstPath = makeStorePath("source", h, baseName);

    return std::pair<Path, Hash>(dstPath, h);
}


Path computeStorePathForText(const string & suffix, const string & s)
{
    Hash hash = hashString(htSHA256, s);
    return makeStorePath("text", hash, suffix);
}


}


#include "local-store.hh"
#include "serialise.hh"
#include "remote-store.hh"


namespace nix {


boost::shared_ptr<StoreAPI> store;


boost::shared_ptr<StoreAPI> openStore(bool reserveSpace)
{
    string mode = getEnv("NIX_REMOTE");
    if (mode == "")
        return boost::shared_ptr<StoreAPI>(new LocalStore(reserveSpace));
    else if (mode == "slave")
        return boost::shared_ptr<StoreAPI>(new RemoteStore());
    else throw Error(format("invalid setting for NIX_REMOTE, `%1%'") % mode);
}


}