Make Path std::filesystem::path not std::string

src/build-remote/build-remote.cc

@@ -81,11 +81,11 @@ static int main_build_remote(int argc, char * * argv)
 
         /* It would be more appropriate to use $XDG_RUNTIME_DIR, since
            that gets cleared on reboot, but it wouldn't work on macOS. */
-        auto currentLoadName = "/current-load";
+        PathView currentLoadName = "current-load";
         if (auto localStore = store.dynamic_pointer_cast<LocalFSStore>())
-            currentLoad = std::string { localStore->stateDir } + currentLoadName;
+            currentLoad = localStore->stateDir / currentLoadName;
         else
-            currentLoad = settings.nixStateDir + currentLoadName;
+            currentLoad = settings.nixStateDir / currentLoadName.native();
 
         std::shared_ptr<Store> sshStore;
         AutoCloseFD bestSlotLock;

src/libcmd/common-eval-args.cc

@@ -192,7 +192,7 @@ Bindings * MixEvalArgs::getAutoArgs(EvalState & state)
     return res.finish();
 }
 
-SourcePath lookupFileArg(EvalState & state, std::string_view s, const Path * baseDir)
+SourcePath lookupFileArg(EvalState & state, PathView s, const Path * baseDir)
 {
     if (EvalSettings::isPseudoUrl(s)) {
         auto accessor = fetchers::downloadTarball(

src/libcmd/common-eval-args.hh

@@ -41,6 +41,6 @@ private:
 /**
  * @param baseDir Optional [base directory](https://nixos.org/manual/nix/unstable/glossary#gloss-base-directory)
  */
-SourcePath lookupFileArg(EvalState & state, std::string_view s, const Path * baseDir = nullptr);
+SourcePath lookupFileArg(EvalState & state, PathView s, const Path * baseDir = nullptr);
 
 }

src/libexpr/eval-error.hh

@@ -4,6 +4,7 @@
 
 #include "error.hh"
 #include "pos-idx.hh"
+#include "file-path.hh"
 
 namespace nix {
 

src/libexpr/eval-settings.cc

@@ -58,7 +58,7 @@ Strings EvalSettings::getDefaultNixPath()
             if (s.empty()) {
                 res.push_back(p);
             } else {
-                res.push_back(s + "=" + p);
+                res.push_back(s + "=" + p.native());
             }
         }
     };

src/libfetchers/git-utils.cc

@@ -421,7 +421,7 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
                 .program = "git",
                 .args = {
                     "-c",
-                    "gpg.ssh.allowedSignersFile=" + allowedSignersFile,
+                    "gpg.ssh.allowedSignersFile=" + allowedSignersFile.string(),
                     "-C", path.string(),
                     "verify-commit",
                     rev.gitRev()

src/libstore/globals.cc

@@ -84,7 +84,9 @@ Settings::Settings()
     }
 
 #if defined(__linux__) && defined(SANDBOX_SHELL)
-    sandboxPaths = tokenizeString<StringSet>("/bin/sh=" SANDBOX_SHELL);
+    sandboxPaths = std::set {
+        Path { "/bin/sh=" SANDBOX_SHELL }
+    };
 #endif
 
     /* chroot-like behavior from Apple's sandbox */
@@ -154,7 +156,7 @@ std::vector<Path> getUserConfigFiles()
     // Use the paths specified in NIX_USER_CONF_FILES if it has been defined
     auto nixConfFiles = getEnv("NIX_USER_CONF_FILES");
     if (nixConfFiles.has_value()) {
-        return tokenizeString<std::vector<std::string>>(nixConfFiles.value(), ":");
+        return tokenizeString<std::vector<Path>>(nixConfFiles.value(), ":");
     }
 
     // Use the paths specified by the XDG spec

src/libstore/globals.hh

@@ -276,7 +276,7 @@ public:
         )"};
 
     Setting<std::string> builders{
-        this, "@" + nixConfDir + "/machines", "builders",
+        this, "@" + (nixConfDir / "machines").native(), "builders",
         R"(
           A semicolon- or newline-separated list of build machines.
 

src/libstore/http-binary-cache-store.cc

@@ -26,7 +26,7 @@ class HttpBinaryCacheStore : public virtual HttpBinaryCacheStoreConfig, public v
 {
 private:
 
-    Path cacheUri;
+    std::string cacheUri;
 
     struct State
     {
@@ -40,7 +40,7 @@ class HttpBinaryCacheStore : public virtual HttpBinaryCacheStoreConfig, public v
 
     HttpBinaryCacheStore(
         const std::string & scheme,
-        const Path & _cacheUri,
+        const std::string & _cacheUri,
         const Params & params)
         : StoreConfig(params)
         , BinaryCacheStoreConfig(params)

src/libstore/local-binary-cache-store.cc

@@ -45,7 +45,7 @@ class LocalBinaryCacheStore : public virtual LocalBinaryCacheStoreConfig, public
 
     std::string getUri() override
     {
-        return "file://" + binaryCacheDir;
+        return "file://" + binaryCacheDir.native();
     }
 
     static std::set<std::string> uriSchemes();

src/libstore/local-fs-store.hh

@@ -16,17 +16,17 @@ struct LocalFSStoreConfig : virtual StoreConfig
         "Directory prefixed to all other paths."};
 
     const PathSetting stateDir{this,
-        rootDir.get() ? *rootDir.get() + "/nix/var/nix" : settings.nixStateDir,
+        rootDir.get() ? *rootDir.get() / "nix/var/nix" : settings.nixStateDir,
         "state",
         "Directory where Nix will store state."};
 
     const PathSetting logDir{this,
-        rootDir.get() ? *rootDir.get() + "/nix/var/log/nix" : settings.nixLogDir,
+        rootDir.get() ? *rootDir.get() / "nix/var/log/nix" : settings.nixLogDir,
         "log",
         "directory where Nix will store log files."};
 
     const PathSetting realStoreDir{this,
-        rootDir.get() ? *rootDir.get() + "/nix/store" : storeDir, "real",
+        rootDir.get() ? *rootDir.get() / "nix/store" : storeDir, "real",
         "Physical path of the Nix store."};
 };
 
@@ -66,7 +66,7 @@ public:
     Path toRealPath(const Path & storePath) override
     {
         assert(isInStore(storePath));
-        return getRealStoreDir() + "/" + std::string(storePath, storeDir.size() + 1);
+        return getRealStoreDir() / Path::string_type { storePath, storeDir.native().size() + 1 };
     }
 
     std::optional<std::string> getBuildLogExact(const StorePath & path) override;

src/libstore/nar-accessor.cc

@@ -15,7 +15,9 @@ struct NarMember
 
     std::string target;
 
-    /* If this is a directory, all the children of the directory. */
+    /**
+     * If this is a directory, all the children of the directory.
+     */
     std::map<std::string, NarMember> children;
 };
 
@@ -71,9 +73,11 @@ struct NarAccessor : public SourceAccessor
             : acc(acc), source(source)
         { }
 
-        NarMember & createMember(const Path & path, NarMember member)
+        NarMember & createMember(const CanonPath & path, NarMember member)
         {
-            size_t level = std::count(path.begin(), path.end(), '/');
+            size_t level = 0;
+            for (auto _ : path) ++level;
+
             while (parents.size() > level) parents.pop();
 
             if (parents.empty()) {
@@ -83,14 +87,14 @@ struct NarAccessor : public SourceAccessor
             } else {
                 if (parents.top()->stat.type != Type::tDirectory)
                     throw Error("NAR file missing parent directory of path '%s'", path);
-                auto result = parents.top()->children.emplace(baseNameOf(path), std::move(member));
+                auto result = parents.top()->children.emplace(*path.baseName(), std::move(member));
                 auto & ref = result.first->second;
                 parents.push(&ref);
                 return ref;
             }
         }
 
-        void createDirectory(const Path & path) override
+        void createDirectory(const CanonPath & path) override
         {
             createMember(path, NarMember{ .stat = {
                 .type = Type::tDirectory,
@@ -100,7 +104,7 @@ struct NarAccessor : public SourceAccessor
             } });
         }
 
-        void createRegularFile(const Path & path, std::function<void(CreateRegularFileSink &)> func) override
+        void createRegularFile(const CanonPath & path, std::function<void(CreateRegularFileSink &)> func) override
         {
             auto & nm = createMember(path, NarMember{ .stat = {
                 .type = Type::tRegular,
@@ -112,7 +116,7 @@ struct NarAccessor : public SourceAccessor
             func(nmc);
         }
 
-        void createSymlink(const Path & path, const std::string & target) override
+        void createSymlink(const CanonPath & path, const std::string & target) override
         {
             createMember(path,
                 NarMember{

src/libstore/nar-info-disk-cache.cc

@@ -208,7 +208,10 @@ class NarInfoDiskCacheImpl : public NarInfoDiskCache
             };
 
             {
-                auto r(state->insertCache.use()(uri)(time(0))(storeDir)(wantMassQuery)(priority));
+                auto r {
+                    state->insertCache.use()
+                        (uri)(time(0))(storeDir.native())(wantMassQuery)(priority)
+                };
                 if (!r.next()) { abort(); }
                 ret.id = (int) r.getInt(0);
             }

src/libstore/path.cc

@@ -89,7 +89,7 @@ std::optional<StorePath> StoreDirConfig::maybeParseStorePath(std::string_view pa
     }
 }
 
-bool StoreDirConfig::isStorePath(std::string_view path) const
+bool StoreDirConfig::isStorePath(PathView path) const
 {
     return (bool) maybeParseStorePath(path);
 }

src/libstore/pathlocks.hh

@@ -2,6 +2,7 @@
 ///@file
 
 #include "file-descriptor.hh"
+#include "file-path.hh"
 
 namespace nix {
 

src/libstore/profiles.cc

@@ -39,7 +39,7 @@ std::pair<Generations, std::optional<GenerationNumber>> findGenerations(Path pro
 
     for (auto & i : readDirectory(profileDir)) {
         if (auto n = parseName(profileName, i.name)) {
-            auto path = profileDir + "/" + i.name;
+            auto path = profileDir / i.name;
             gens.push_back({
                 .number = *n,
                 .path = path,
@@ -255,7 +255,7 @@ time_t parseOlderThanTimeSpec(std::string_view timeSpec)
 void switchLink(Path link, Path target)
 {
     /* Hacky. */
-    if (dirOf(target) == dirOf(link)) target = baseNameOf(target);
+    if (dirOf(target) == dirOf(link)) target = baseNameOf(target).native();
 
     replaceSymlink(target, link);
 }
@@ -310,28 +310,30 @@ Path profilesDir()
     auto profileRoot =
         isRootUser()
         ? rootProfilesDir()
-        : createNixStateDir() + "/profiles";
+        : createNixStateDir() / "profiles";
     createDirs(profileRoot);
     return profileRoot;
 }
 
 Path rootProfilesDir()
 {
-    return settings.nixStateDir + "/profiles/per-user/root";
+    return settings.nixStateDir / "profiles/per-user/root";
 }
 
 
 Path getDefaultProfile()
 {
-    Path profileLink = settings.useXDGBaseDirectories ? createNixStateDir() + "/profile" : getHome() + "/.nix-profile";
+    Path profileLink = settings.useXDGBaseDirectories
+        ? createNixStateDir() / "profile"
+        : getHome() / ".nix-profile";
     try {
-        auto profile = profilesDir() + "/profile";
+        auto profile = profilesDir() / "profile";
         if (!pathExists(profileLink)) {
             replaceSymlink(profile, profileLink);
         }
         // Backwards compatibiliy measure: Make root's profile available as
         // `.../default` as it's what NixOS and most of the init scripts expect
-        Path globalProfileLink = settings.nixStateDir + "/profiles/default";
+        Path globalProfileLink = settings.nixStateDir / "profiles/default";
         if (isRootUser() && !pathExists(globalProfileLink)) {
             replaceSymlink(profile, globalProfileLink);
         }
@@ -345,12 +347,12 @@ Path getDefaultProfile()
 
 Path defaultChannelsDir()
 {
-    return profilesDir() + "/channels";
+    return profilesDir() / "channels";
 }
 
 Path rootChannelsDir()
 {
-    return rootProfilesDir() + "/channels";
+    return rootProfilesDir() / "channels";
 }
 
 }

src/libstore/sqlite.cc

@@ -62,7 +62,7 @@ SQLite::SQLite(const Path & path, SQLiteOpenMode mode)
     bool immutable = mode == SQLiteOpenMode::Immutable;
     int flags = immutable ? SQLITE_OPEN_READONLY : SQLITE_OPEN_READWRITE;
     if (mode == SQLiteOpenMode::Normal) flags |= SQLITE_OPEN_CREATE;
-    auto uri = "file:" + percentEncode(path) + "?immutable=" + (immutable ? "1" : "0");
+    auto uri = "file:" + percentEncode(path.native()) + "?immutable=" + (immutable ? "1" : "0");
     int ret = sqlite3_open_v2(uri.c_str(), &db, SQLITE_OPEN_URI | flags, vfs);
     if (ret != SQLITE_OK) {
         const char * err = sqlite3_errstr(ret);

src/libstore/sqlite.hh

@@ -5,6 +5,7 @@
 #include <string>
 
 #include "error.hh"
+#include "file-path.hh"
 
 struct sqlite3;
 struct sqlite3_stmt;

src/libstore/ssh.cc

@@ -35,7 +35,7 @@ void SSHMaster::addCommonSSHOpts(Strings & args)
         auto p = host.rfind("@");
         std::string thost = p != std::string::npos ? std::string(host, p + 1) : host;
         writeFile(fileName, thost + " " + base64Decode(sshPublicHostKey) + "\n");
-        args.insert(args.end(), {"-oUserKnownHostsFile=" + fileName});
+        args.insert(args.end(), {"-oUserKnownHostsFile=" + fileName.native()});
     }
     if (compress)
         args.push_back("-C");

src/libstore/store-api.hh

@@ -224,13 +224,13 @@ public:
     /**
      * Follow symlinks until we end up with a path in the Nix store.
      */
-    Path followLinksToStore(std::string_view path) const;
+    Path followLinksToStore(PathView path) const;
 
     /**
      * Same as followLinksToStore(), but apply toStorePath() to the
      * result.
      */
-    StorePath followLinksToStorePath(std::string_view path) const;
+    StorePath followLinksToStorePath(PathView path) const;
 
     /**
      * Check whether a path is valid.

src/libstore/store-dir-config.hh

@@ -67,7 +67,7 @@ struct StoreDirConfig : public Config
      * @return true if ‘path’ is a store path, i.e. a direct child of the
      * Nix store.
      */
-    bool isStorePath(std::string_view path) const;
+    bool isStorePath(PathView path) const;
 
     /**
      * Split a path like /nix/store/<hash>-<name>/<bla> into

src/libstore/uds-remote-store.cc

@@ -52,7 +52,7 @@ UDSRemoteStore::UDSRemoteStore(
 std::string UDSRemoteStore::getUri()
 {
     if (path) {
-        return std::string("unix://") + *path;
+        return std::string { "unix://" } + path->native();
     } else {
         return "daemon";
     }

src/libstore/uds-remote-store.hh

@@ -60,7 +60,7 @@ private:
     };
 
     ref<RemoteStore::Connection> openConnection() override;
-    std::optional<std::string> path;
+    std::optional<Path> path;
 };
 
 }

src/libstore/unix/local-overlay-store.md

@@ -4,7 +4,7 @@ R"(
 
 This store type is a variation of the [local store] designed to leverage Linux's [Overlay Filesystem](https://docs.kernel.org/filesystems/overlayfs.html) (OverlayFS for short).
 Just as OverlayFS combines a lower and upper filesystem by treating the upper one as a patch against the lower, the local overlay store combines a lower store with an upper almost-[local store].
-("almost" because while the upper fileystems for OverlayFS is valid on its own, the upper almost-store is not a valid local store on its own because some references will dangle.)
+("almost" because while the upper filesystems for OverlayFS is valid on its own, the upper almost-store is not a valid local store on its own because some references will dangle.)
 To use this store, you will first need to configure an OverlayFS mountpoint [appropriately](#example-filesystem-layout) as Nix will not do this for you (though it will verify the mountpoint is configured correctly).
 
 ### Conceptual parts of a local overlay store