Renamed HashFormat::Base32 to HashFormat::Nix32

...and also adjusted parsing accordingly.

Also added CLI completion for HashFormats.

NixOS#8876

src/libexpr/primops/fetchTree.cc

@@ -304,7 +304,7 @@ static void fetch(EvalState & state, const PosIdx pos, Value * * args, Value & v
             : hashFile(HashAlgorithm::SHA256, state.store->toRealPath(storePath));
         if (hash != *expectedHash)
             state.debugThrowLastTrace(EvalError((unsigned int) 102, "hash mismatch in file downloaded from '%s':\n  specified: %s\n  got:       %s",
-                *url, expectedHash->to_string(HashFormat::Base32, true), hash.to_string(HashFormat::Base32, true)));
+                                                *url, expectedHash->to_string(HashFormat::Nix32, true), hash.to_string(HashFormat::Nix32, true)));
     }
 
     state.allowAndSetStorePathString(storePath, v);

src/libfetchers/git.cc

@@ -52,7 +52,7 @@ bool touchCacheFile(const Path & path, time_t touch_time)
 Path getCachePath(std::string_view key)
 {
     return getCacheDir() + "/nix/gitv3/" +
-        hashString(HashAlgorithm::SHA256, key).to_string(HashFormat::Base32, false);
+        hashString(HashAlgorithm::SHA256, key).to_string(HashFormat::Nix32, false);
 }
 
 // Returns the name of the HEAD branch.

src/libfetchers/mercurial.cc

@@ -267,7 +267,7 @@ struct MercurialInputScheme : InputScheme
             }
         }
 
-        Path cacheDir = fmt("%s/nix/hg/%s", getCacheDir(), hashString(HashAlgorithm::SHA256, actualUrl).to_string(HashFormat::Base32, false));
+        Path cacheDir = fmt("%s/nix/hg/%s", getCacheDir(), hashString(HashAlgorithm::SHA256, actualUrl).to_string(HashFormat::Nix32, false));
 
         /* If this is a commit hash that we already have, we don't
            have to pull again. */

src/libstore/binary-cache-store.cc

@@ -165,8 +165,8 @@ ref<const ValidPathInfo> BinaryCacheStore::addToStoreCommon(
     auto [fileHash, fileSize] = fileHashSink.finish();
     narInfo->fileHash = fileHash;
     narInfo->fileSize = fileSize;
-    narInfo->url = "nar/" + narInfo->fileHash->to_string(HashFormat::Base32, false) + ".nar"
-        + (compression == "xz" ? ".xz" :
+    narInfo->url = "nar/" + narInfo->fileHash->to_string(HashFormat::Nix32, false) + ".nar"
+                   + (compression == "xz" ? ".xz" :
            compression == "bzip2" ? ".bz2" :
            compression == "zstd" ? ".zst" :
            compression == "lzip" ? ".lzip" :

src/libstore/build/local-derivation-goal.cc

@@ -1067,7 +1067,7 @@ void LocalDerivationGoal::initTmpDir() {
                 env[i.first] = i.second;
             } else {
                 auto hash = hashString(HashAlgorithm::SHA256, i.first);
-                std::string fn = ".attr-" + hash.to_string(HashFormat::Base32, false);
+                std::string fn = ".attr-" + hash.to_string(HashFormat::Nix32, false);
                 Path p = tmpDir + "/" + fn;
                 writeFile(p, rewriteStrings(i.second, inputRewrites));
                 chownToBuilder(p);

src/libstore/content-address.cc

@@ -61,7 +61,7 @@ std::string ContentAddress::render() const
                 + makeFileIngestionPrefix(method);
         },
     }, method.raw)
-        + this->hash.to_string(HashFormat::Base32, true);
+        + this->hash.to_string(HashFormat::Nix32, true);
 }
 
 /**

src/libstore/derivations.cc

@@ -958,7 +958,7 @@ void writeDerivation(Sink & out, const StoreDirConfig & store, const BasicDeriva
 std::string hashPlaceholder(const OutputNameView outputName)
 {
     // FIXME: memoize?
-    return "/" + hashString(HashAlgorithm::SHA256, concatStrings("nix-output:", outputName)).to_string(HashFormat::Base32, false);
+    return "/" + hashString(HashAlgorithm::SHA256, concatStrings("nix-output:", outputName)).to_string(HashFormat::Nix32, false);
 }
 
 

src/libstore/downstream-placeholder.cc

@@ -5,7 +5,7 @@ namespace nix {
 
 std::string DownstreamPlaceholder::render() const
 {
-    return "/" + hash.to_string(HashFormat::Base32, false);
+    return "/" + hash.to_string(HashFormat::Nix32, false);
 }
 
 
@@ -31,7 +31,7 @@ DownstreamPlaceholder DownstreamPlaceholder::unknownDerivation(
     xpSettings.require(Xp::DynamicDerivations);
     auto compressed = compressHash(placeholder.hash, 20);
     auto clearText = "nix-computed-output:"
-        + compressed.to_string(HashFormat::Base32, false)
+        + compressed.to_string(HashFormat::Nix32, false)
         + ":" + std::string { outputName };
     return DownstreamPlaceholder {
         hashString(HashAlgorithm::SHA256, clearText)

src/libstore/export-import.cc

@@ -41,7 +41,7 @@ void Store::exportPath(const StorePath & path, Sink & sink)
     Hash hash = hashSink.currentHash().first;
     if (hash != info->narHash && info->narHash != Hash(info->narHash.algo))
         throw Error("hash of path '%s' has changed from '%s' to '%s'!",
-            printStorePath(path), info->narHash.to_string(HashFormat::Base32, true), hash.to_string(HashFormat::Base32, true));
+                    printStorePath(path), info->narHash.to_string(HashFormat::Nix32, true), hash.to_string(HashFormat::Nix32, true));
 
     teeSink
         << exportMagic

src/libstore/gc.cc

@@ -50,7 +50,7 @@ static void makeSymlink(const Path & link, const Path & target)
 
 void LocalStore::addIndirectRoot(const Path & path)
 {
-    std::string hash = hashString(HashAlgorithm::SHA1, path).to_string(HashFormat::Base32, false);
+    std::string hash = hashString(HashAlgorithm::SHA1, path).to_string(HashFormat::Nix32, false);
     Path realRoot = canonPath(fmt("%1%/%2%/auto/%3%", stateDir, gcRootsDir, hash));
     makeSymlink(realRoot, path);
 }

src/libstore/local-store.cc

@@ -1080,7 +1080,7 @@ void LocalStore::addToStore(const ValidPathInfo & info, Source & source,
 
             if (hashResult.first != info.narHash)
                 throw Error("hash mismatch importing path '%s';\n  specified: %s\n  got:       %s",
-                    printStorePath(info.path), info.narHash.to_string(HashFormat::Base32, true), hashResult.first.to_string(HashFormat::Base32, true));
+                            printStorePath(info.path), info.narHash.to_string(HashFormat::Nix32, true), hashResult.first.to_string(HashFormat::Nix32, true));
 
             if (hashResult.second != info.narSize)
                 throw Error("size mismatch importing path '%s';\n  specified: %s\n  got:       %s",
@@ -1096,8 +1096,8 @@ void LocalStore::addToStore(const ValidPathInfo & info, Source & source,
                 if (specified.hash != actualHash.hash) {
                     throw Error("ca hash mismatch importing path '%s';\n  specified: %s\n  got:       %s",
                         printStorePath(info.path),
-                        specified.hash.to_string(HashFormat::Base32, true),
-                        actualHash.hash.to_string(HashFormat::Base32, true));
+                        specified.hash.to_string(HashFormat::Nix32, true),
+                        actualHash.hash.to_string(HashFormat::Nix32, true));
                 }
             }
 
@@ -1389,7 +1389,7 @@ bool LocalStore::verifyStore(bool checkContents, RepairFlag repair)
         for (auto & link : readDirectory(linksDir)) {
             printMsg(lvlTalkative, "checking contents of '%s'", link.name);
             Path linkPath = linksDir + "/" + link.name;
-            std::string hash = hashPath(HashAlgorithm::SHA256, linkPath).first.to_string(HashFormat::Base32, false);
+            std::string hash = hashPath(HashAlgorithm::SHA256, linkPath).first.to_string(HashFormat::Nix32, false);
             if (hash != link.name) {
                 printError("link '%s' was modified! expected hash '%s', got '%s'",
                     linkPath, link.name, hash);
@@ -1422,7 +1422,7 @@ bool LocalStore::verifyStore(bool checkContents, RepairFlag repair)
 
                 if (info->narHash != nullHash && info->narHash != current.first) {
                     printError("path '%s' was modified! expected hash '%s', got '%s'",
-                        printStorePath(i), info->narHash.to_string(HashFormat::Base32, true), current.first.to_string(HashFormat::Base32, true));
+                               printStorePath(i), info->narHash.to_string(HashFormat::Nix32, true), current.first.to_string(HashFormat::Nix32, true));
                     if (repair) repairPath(i); else errors = true;
                 } else {
 

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

@@ -333,9 +333,9 @@ class NarInfoDiskCacheImpl : public NarInfoDiskCache
                     (std::string(info->path.name()))
                     (narInfo ? narInfo->url : "", narInfo != 0)
                     (narInfo ? narInfo->compression : "", narInfo != 0)
-                    (narInfo && narInfo->fileHash ? narInfo->fileHash->to_string(HashFormat::Base32, true) : "", narInfo && narInfo->fileHash)
+                    (narInfo && narInfo->fileHash ? narInfo->fileHash->to_string(HashFormat::Nix32, true) : "", narInfo && narInfo->fileHash)
                     (narInfo ? narInfo->fileSize : 0, narInfo != 0 && narInfo->fileSize)
-                    (info->narHash.to_string(HashFormat::Base32, true))
+                    (info->narHash.to_string(HashFormat::Nix32, true))
                     (info->narSize)
                     (concatStringsSep(" ", info->shortRefs()))
                     (info->deriver ? std::string(info->deriver->to_string()) : "", (bool) info->deriver)

src/libstore/nar-info.cc

@@ -114,10 +114,10 @@ std::string NarInfo::to_string(const Store & store) const
     assert(compression != "");
     res += "Compression: " + compression + "\n";
     assert(fileHash && fileHash->algo == HashAlgorithm::SHA256);
-    res += "FileHash: " + fileHash->to_string(HashFormat::Base32, true) + "\n";
+    res += "FileHash: " + fileHash->to_string(HashFormat::Nix32, true) + "\n";
     res += "FileSize: " + std::to_string(fileSize) + "\n";
     assert(narHash.algo == HashAlgorithm::SHA256);
-    res += "NarHash: " + narHash.to_string(HashFormat::Base32, true) + "\n";
+    res += "NarHash: " + narHash.to_string(HashFormat::Nix32, true) + "\n";
     res += "NarSize: " + std::to_string(narSize) + "\n";
 
     res += "References: " + concatStringsSep(" ", shortRefs()) + "\n";

src/libstore/optimise-store.cc

@@ -147,10 +147,10 @@ void LocalStore::optimisePath_(Activity * act, OptimiseStats & stats,
        contents of the symlink (i.e. the result of readlink()), not
        the contents of the target (which may not even exist). */
     Hash hash = hashPath(HashAlgorithm::SHA256, path).first;
-    debug("'%1%' has hash '%2%'", path, hash.to_string(HashFormat::Base32, true));
+    debug("'%1%' has hash '%2%'", path, hash.to_string(HashFormat::Nix32, true));
 
     /* Check if this is a known hash. */
-    Path linkPath = linksDir + "/" + hash.to_string(HashFormat::Base32, false);
+    Path linkPath = linksDir + "/" + hash.to_string(HashFormat::Nix32, false);
 
     /* Maybe delete the link, if it has been corrupted. */
     if (pathExists(linkPath)) {

src/libstore/parsed-derivations.cc

@@ -146,7 +146,7 @@ static nlohmann::json pathInfoToJSON(
         auto info = store.queryPathInfo(storePath);
 
         auto & jsonPath = jsonList.emplace_back(
-            info->toJSON(store, false, HashFormat::Base32));
+            info->toJSON(store, false, HashFormat::Nix32));
 
         // Add the path to the object whose metadata we are including.
         jsonPath["path"] = store.printStorePath(storePath);

src/libstore/path-info.cc

@@ -31,9 +31,9 @@ std::string ValidPathInfo::fingerprint(const Store & store) const
         throw Error("cannot calculate fingerprint of path '%s' because its size is not known",
             store.printStorePath(path));
     return
-        "1;" + store.printStorePath(path) + ";"
-        + narHash.to_string(HashFormat::Base32, true) + ";"
-        + std::to_string(narSize) + ";"
+            "1;" + store.printStorePath(path) + ";"
+            + narHash.to_string(HashFormat::Nix32, true) + ";"
+            + std::to_string(narSize) + ";"
         + concatStringsSep(",", store.printStorePathSet(references));
 }
 

src/libstore/path.cc

@@ -35,7 +35,7 @@ StorePath::StorePath(std::string_view _baseName)
 }
 
 StorePath::StorePath(const Hash & hash, std::string_view _name)
-    : baseName((hash.to_string(HashFormat::Base32, false) + "-").append(std::string(_name)))
+    : baseName((hash.to_string(HashFormat::Nix32, false) + "-").append(std::string(_name)))
 {
     checkName(baseName, name());
 }

src/libutil/args.cc

@@ -544,11 +544,45 @@ nlohmann::json Args::toJSON()
     return res;
 }
 
+static void hashFormatCompleter(AddCompletions & completions, size_t index, std::string_view prefix)
+{
+    for (auto & format : hashFormats) {
+        if (hasPrefix(format, prefix)) {
+            completions.add(format);
+        }
+    }
+}
+
+Args::Flag Args::Flag::mkHashFormatFlagWithDefault(std::string &&longName, HashFormat * hf) {
+    assert(*hf == nix::HashFormat::SRI);
+    return Flag{
+            .longName = std::move(longName),
+            .description = "hash format ('base16', 'nix32', 'base64', 'sri'). Default: 'sri'",
+            .labels = {"hash-format"},
+            .handler = {[hf](std::string s) {
+                *hf = parseHashFormat(s);
+            }},
+            .completer = hashFormatCompleter,
+    };
+}
+
+Args::Flag Args::Flag::mkHashFormatOptFlag(std::string && longName, std::optional<HashFormat> * ohf) {
+    return Flag{
+            .longName = std::move(longName),
+            .description = "hash format ('base16', 'nix32', 'base64', 'sri').",
+            .labels = {"hash-format"},
+            .handler = {[ohf](std::string s) {
+                *ohf = std::optional<HashFormat>{parseHashFormat(s)};
+            }},
+            .completer = hashFormatCompleter,
+    };
+}
+
 static void hashAlgoCompleter(AddCompletions & completions, size_t index, std::string_view prefix)
 {
-    for (auto & type : hashAlgorithms)
-        if (hasPrefix(type, prefix))
-            completions.add(type);
+    for (auto & algo : hashAlgorithms)
+        if (hasPrefix(algo, prefix))
+            completions.add(algo);
 }
 
 Args::Flag Args::Flag::mkHashAlgoFlag(std::string && longName, HashAlgorithm * ha)

src/libutil/args.hh

@@ -15,6 +15,7 @@
 namespace nix {
 
 enum struct HashAlgorithm : char;
+enum struct HashFormat : int;
 
 class MultiCommand;
 
@@ -177,6 +178,8 @@ protected:
 
         static Flag mkHashAlgoFlag(std::string && longName, HashAlgorithm * ha);
         static Flag mkHashAlgoOptFlag(std::string && longName, std::optional<HashAlgorithm> * oha);
+        static Flag mkHashFormatFlagWithDefault(std::string && longName, HashFormat * hf);
+        static Flag mkHashFormatOptFlag(std::string && longName, std::optional<HashFormat> * ohf);
     };
 
     /**

src/libutil/hash.cc

@@ -27,8 +27,9 @@ static size_t regularHashSize(HashAlgorithm type) {
 }
 
 
-std::set<std::string> hashAlgorithms = {"md5", "sha1", "sha256", "sha512" };
+const std::set<std::string> hashAlgorithms = {"md5", "sha1", "sha256", "sha512" };
 
+const std::set<std::string> hashFormats = {"base64", "nix32", "base16", "sri" };
 
 Hash::Hash(HashAlgorithm algo) : algo(algo)
 {
@@ -81,7 +82,7 @@ static std::string printHash16(const Hash & hash)
 
 
 // omitted: E O U T
-const std::string base32Chars = "0123456789abcdfghijklmnpqrsvwxyz";
+const std::string nix32Chars = "0123456789abcdfghijklmnpqrsvwxyz";
 
 
 static std::string printHash32(const Hash & hash)
@@ -100,7 +101,7 @@ static std::string printHash32(const Hash & hash)
         unsigned char c =
             (hash.hash[i] >> j)
             | (i >= hash.hashSize - 1 ? 0 : hash.hash[i + 1] << (8 - j));
-        s.push_back(base32Chars[c & 0x1f]);
+        s.push_back(nix32Chars[c & 0x1f]);
     }
 
     return s;
@@ -110,7 +111,7 @@ static std::string printHash32(const Hash & hash)
 std::string printHash16or32(const Hash & hash)
 {
     assert(static_cast<char>(hash.algo));
-    return hash.to_string(hash.algo == HashAlgorithm::MD5 ? HashFormat::Base16 : HashFormat::Base32, false);
+    return hash.to_string(hash.algo == HashAlgorithm::MD5 ? HashFormat::Base16 : HashFormat::Nix32, false);
 }
 
 
@@ -125,7 +126,7 @@ std::string Hash::to_string(HashFormat hashFormat, bool includeAlgo) const
     case HashFormat::Base16:
         s += printHash16(*this);
         break;
-    case HashFormat::Base32:
+    case HashFormat::Nix32:
         s += printHash32(*this);
         break;
     case HashFormat::Base64:
@@ -230,8 +231,8 @@ Hash::Hash(std::string_view rest, HashAlgorithm algo, bool isSRI)
         for (unsigned int n = 0; n < rest.size(); ++n) {
             char c = rest[rest.size() - n - 1];
             unsigned char digit;
-            for (digit = 0; digit < base32Chars.size(); ++digit) /* !!! slow */
-                if (base32Chars[digit] == c) break;
+            for (digit = 0; digit < nix32Chars.size(); ++digit) /* !!! slow */
+                if (nix32Chars[digit] == c) break;
             if (digit >= 32)
                 throw BadHash("invalid base-32 hash '%s'", rest);
             unsigned int b = n * 5;
@@ -388,7 +389,11 @@ Hash compressHash(const Hash & hash, unsigned int newSize)
 std::optional<HashFormat> parseHashFormatOpt(std::string_view hashFormatName)
 {
     if (hashFormatName == "base16") return HashFormat::Base16;
-    if (hashFormatName == "base32") return HashFormat::Base32;
+    if (hashFormatName == "nix32") return HashFormat::Nix32;
+    if (hashFormatName == "base32") {
+        warn(R"("base32" is a deprecated alias for hash format "nix32".)");
+        return HashFormat::Nix32;
+    }
     if (hashFormatName == "base64") return HashFormat::Base64;
     if (hashFormatName == "sri") return HashFormat::SRI;
     return std::nullopt;
@@ -407,8 +412,8 @@ std::string_view printHashFormat(HashFormat HashFormat)
     switch (HashFormat) {
     case HashFormat::Base64:
         return "base64";
-    case HashFormat::Base32:
-        return "base32";
+    case HashFormat::Nix32:
+        return "nix32";
     case HashFormat::Base16:
         return "base16";
     case HashFormat::SRI:

src/libutil/hash.hh

@@ -20,9 +20,9 @@ const int sha1HashSize = 20;
 const int sha256HashSize = 32;
 const int sha512HashSize = 64;
 
-extern std::set<std::string> hashAlgorithms;
+extern const std::set<std::string> hashAlgorithms;
 
-extern const std::string base32Chars;
+extern const std::string nix32Chars;
 
 /**
  * @brief Enumeration representing the hash formats.
@@ -31,15 +31,17 @@ enum struct HashFormat : int {
     /// @brief Base 64 encoding.
     /// @see [IETF RFC 4648, section 4](https://datatracker.ietf.org/doc/html/rfc4648#section-4).
     Base64,
-    /// @brief Nix-specific base-32 encoding. @see base32Chars
-    Base32,
+    /// @brief Nix-specific base-32 encoding. @see nix32Chars
+    Nix32,
     /// @brief Lowercase hexadecimal encoding. @see base16Chars
     Base16,
     /// @brief "<hash algo>:<Base 64 hash>", format of the SRI integrity attribute.
     /// @see W3C recommendation [Subresource Intergrity](https://www.w3.org/TR/SRI/).
     SRI
 };
 
+extern const std::set<std::string> hashFormats;
+
 struct Hash
 {
     constexpr static size_t maxHashSize = 64;

src/libutil/references.cc

@@ -23,8 +23,8 @@ static void search(
     static bool isBase32[256];
     std::call_once(initialised, [](){
         for (unsigned int i = 0; i < 256; ++i) isBase32[i] = false;
-        for (unsigned int i = 0; i < base32Chars.size(); ++i)
-            isBase32[(unsigned char) base32Chars[i]] = true;
+        for (unsigned int i = 0; i < nix32Chars.size(); ++i)
+            isBase32[(unsigned char) nix32Chars[i]] = true;
     });
 
     for (size_t i = 0; i + refLength <= s.size(); ) {