wroclaw-git-backups/nix
1
0
Fork 0
mirror of https://github.com/NixOS/nix synced 2025-06-29 14:53:16 +02:00
Code Activity

Encode virtual paths as /nix/store/virtual000<N>

Browse source 
This makes lib.isStorePath in nixpkgs return true for source trees and
fixes some cases where /__nix_virtual__ showed up in the NixOS manual.
This commit is contained in:
Eelco Dolstra 2022-10-27 15:57:56 +02:00
parent e424a8b196
commit a653e98f55
4 changed files with 19 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

1
src/libexpr/eval.cc
View file

@ -500,6 +500,7 @@ EvalState::EvalState(
, valueAllocCache(std::make_shared<void *>(nullptr))
, env1AllocCache(std::make_shared<void *>(nullptr))
#endif
, virtualPathMarker(settings.nixStore + "/virtual00000000000000000")
, baseEnv(allocEnv(128))
, staticBaseEnv{std::make_shared<StaticEnv>(false, nullptr)}
{

6
src/libexpr/eval.hh
View file

@ -227,14 +227,16 @@ public:
void registerAccessor(ref<InputAccessor> accessor);
/* Convert a path to a string representation of the format
`/__nix_virtual__/<accessor-number>/<path>`. */
`/nix/store/virtual000...<accessor-number>/<path>`. */
std::string encodePath(const SourcePath & path);
/* Decode a path encoded by `encodePath()`. */
SourcePath decodePath(std::string_view s, PosIdx pos = noPos);
const std::string virtualPathMarker;
/* Decode all virtual paths in a string, i.e. all
/__nix_virtual__/... substrings are replaced by the
/nix/store/virtual000... substrings are replaced by the
corresponding input accessor. */
std::string decodePaths(std::string_view s);

14
src/libexpr/paths.cc
View file

@ -14,18 +14,16 @@ void EvalState::registerAccessor(ref<InputAccessor> accessor)
inputAccessors.emplace(accessor->number, accessor);
}
static constexpr std::string_view marker = "/__nix_virtual__/";
std::string EvalState::encodePath(const SourcePath & path)
{
/* For backward compatibility, return paths in the root FS
normally. Encoding any other path is not very reproducible (due
to /__nix_virtual__/<N>) and we should depreceate it
to /nix/store/virtual000...<N>) and we should deprecate it
eventually. So print a warning about use of an encoded path in
decodePath(). */
return path.accessor == rootFS
? path.path.abs()
: std::string(marker) + std::to_string(path.accessor->number) + path.path.abs();
: fmt("%s%08x-source%s", virtualPathMarker, path.accessor->number, path.path.absOrEmpty());
}
SourcePath EvalState::decodePath(std::string_view s, PosIdx pos)
@ -33,17 +31,17 @@ SourcePath EvalState::decodePath(std::string_view s, PosIdx pos)
if (!hasPrefix(s, "/"))
throwEvalError(pos, "string '%1%' doesn't represent an absolute path", s);
if (hasPrefix(s, marker)) {
if (hasPrefix(s, virtualPathMarker)) {
auto fail = [s]() {
throw Error("cannot decode virtual path '%s'", s);
};
s = s.substr(marker.size());
s = s.substr(virtualPathMarker.size());
try {
auto slash = s.find('/');
if (slash == std::string::npos) fail();
size_t number = std::stoi(std::string(s, 0, slash));
size_t number = std::stoi(std::string(s, 0, slash), nullptr, 16);
s = s.substr(slash);
auto accessor = inputAccessors.find(number);
@ -70,7 +68,7 @@ std::string EvalState::decodePaths(std::string_view s)
size_t pos = 0;
while (true) {
auto m = s.find(marker, pos);
auto m = s.find(virtualPathMarker, pos);
if (m == s.npos) {
res.append(s.substr(pos));
return res;