From fb05a6adcfe0362249bd16527a2e44ea2611e5f3 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Tue, 16 Jun 2020 12:45:36 -0400
Subject: [PATCH 01/15] Eliminate old TeeSink abstraction

This was introduced in fa125b9b28bea25a4eeb4d39a71a481563127cb9, and
then "reverted" in 1cf480110879ffc8aee94b4b75999da405b71d7c, except that
revert left the struct around doing nothing useful.

We're removing it all the way now because we want to make a new
`TeeSink` complementing the already-exiting `TeeSource`, that is
actually a completely different concept as far as the class hierarchy is
concerned.
---
 src/libstore/daemon.cc        |  7 ++++---
 src/libstore/export-import.cc | 11 ++++++-----
 src/libutil/archive.hh        |  7 -------
 3 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/src/libstore/daemon.cc b/src/libstore/daemon.cc
index e370e278c..b2e37c5b5 100644
--- a/src/libstore/daemon.cc
+++ b/src/libstore/daemon.cc
@@ -721,9 +721,10 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
         if (GET_PROTOCOL_MINOR(clientVersion) >= 21)
             source = std::make_unique<TunnelSource>(from, to);
         else {
-            TeeSink tee(from);
-            parseDump(tee, tee.source);
-            saved = std::move(*tee.source.data);
+            TeeSource tee(from);
+            ParseSink sink;
+            parseDump(sink, tee);
+            saved = std::move(*tee.data);
             source = std::make_unique<StringSource>(saved);
         }
 
diff --git a/src/libstore/export-import.cc b/src/libstore/export-import.cc
index cb9da027d..0e33fb687 100644
--- a/src/libstore/export-import.cc
+++ b/src/libstore/export-import.cc
@@ -77,8 +77,9 @@ StorePaths Store::importPaths(Source & source, std::shared_ptr<FSAccessor> acces
         if (n != 1) throw Error("input doesn't look like something created by 'nix-store --export'");
 
         /* Extract the NAR from the source. */
-        TeeSink tee(source);
-        parseDump(tee, tee.source);
+        TeeSource tee(source);
+        ParseSink sink;
+        parseDump(sink, tee);
 
         uint32_t magic = readInt(source);
         if (magic != exportMagic)
@@ -94,15 +95,15 @@ StorePaths Store::importPaths(Source & source, std::shared_ptr<FSAccessor> acces
         if (deriver != "")
             info.deriver = parseStorePath(deriver);
 
-        info.narHash = hashString(htSHA256, *tee.source.data);
-        info.narSize = tee.source.data->size();
+        info.narHash = hashString(htSHA256, *tee.data);
+        info.narSize = tee.data->size();
 
         // Ignore optional legacy signature.
         if (readInt(source) == 1)
             readString(source);
 
         // Can't use underlying source, which would have been exhausted
-        auto source = StringSource { *tee.source.data };
+        auto source = StringSource { *tee.data };
         addToStore(info, source, NoRepair, checkSigs, accessor);
 
         res.push_back(info.path);
diff --git a/src/libutil/archive.hh b/src/libutil/archive.hh
index 768fe2536..32d98a610 100644
--- a/src/libutil/archive.hh
+++ b/src/libutil/archive.hh
@@ -63,13 +63,6 @@ struct ParseSink
     virtual void createSymlink(const Path & path, const string & target) { };
 };
 
-struct TeeSink : ParseSink
-{
-    TeeSource source;
-
-    TeeSink(Source & source) : source(source) { }
-};
-
 void parseDump(ParseSink & sink, Source & source);
 
 void restorePath(const Path & path, Source & source);

From 289b9b8dcf8dc651c2d245d9328911f7addd1626 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Tue, 16 Jun 2020 15:14:11 -0400
Subject: [PATCH 02/15] Create a new TeeSink abstraction

This is a bit complex because we want to expose extra functionality the
wrapped class has. Perhaps there is some inheritancy trickery to do this
nicer, but I don't know it, and this is the first thing we tried after a
series of attempts that did build.

This design is kind of like that of Rust's Writer, Reader, or Iter
adapters, which impliment more traits based on what the inner type
implements.
---
 src/libutil/compression.hh | 12 ++++++++++++
 src/libutil/serialise.hh   | 22 ++++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/src/libutil/compression.hh b/src/libutil/compression.hh
index dd666a4e1..1bd118b47 100644
--- a/src/libutil/compression.hh
+++ b/src/libutil/compression.hh
@@ -25,4 +25,16 @@ MakeError(UnknownCompressionMethod, Error);
 
 MakeError(CompressionError, Error);
 
+template<>
+struct TeeSink<ref<CompressionSink>> : CompressionSink
+{
+    MAKE_TEE_SINK(ref<CompressionSink>);
+    void finish() override {
+        orig->finish();
+    }
+    void write(const unsigned char * data, size_t len) override {
+        return orig->write(data, len);
+    }
+};
+
 }
diff --git a/src/libutil/serialise.hh b/src/libutil/serialise.hh
index a04118512..88a6b7ffe 100644
--- a/src/libutil/serialise.hh
+++ b/src/libutil/serialise.hh
@@ -181,6 +181,28 @@ struct TeeSource : Source
     }
 };
 
+#define MAKE_TEE_SINK(T) \
+	T orig; \
+    ref<std::string> data; \
+    TeeSink(T && orig) \
+        : orig(std::move(orig)), data(make_ref<std::string>()) { } \
+    void operator () (const unsigned char * data, size_t len) { \
+        this->data->append((const char *) data, len); \
+        (*this->orig)(data, len); \
+    } \
+    void operator () (const std::string & s) \
+    { \
+        *data += s; \
+        (*this->orig)(s); \
+    }
+
+template<typename T>
+struct TeeSink : Sink
+{
+    MAKE_TEE_SINK(T);
+};
+
+
 /* A reader that consumes the original Source until 'size'. */
 struct SizedSource : Source
 {

From a835c740ca67e063fe47e7c31444b7c1cac0fe81 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Tue, 16 Jun 2020 15:14:11 -0400
Subject: [PATCH 03/15] Replace `TransferItem::status` with a local variable

Everywhere seems to use `getHTTPStatus` now.
---
 src/libstore/filetransfer.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index 531b85af8..9566e0ae9 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -56,7 +56,6 @@ struct curlFileTransfer : public FileTransfer
         Callback<FileTransferResult> callback;
         CURL * req = 0;
         bool active = false; // whether the handle has been added to the multi object
-        std::string status;
 
         unsigned int attempt = 0;
 
@@ -175,6 +174,7 @@ struct curlFileTransfer : public FileTransfer
             size_t realSize = size * nmemb;
             std::string line((char *) contents, realSize);
             printMsg(lvlVomit, format("got header for '%s': %s") % request.uri % trim(line));
+            std::string status;
             if (line.compare(0, 5, "HTTP/") == 0) { // new response starts
                 result.etag = "";
                 auto ss = tokenizeString<vector<string>>(line, " ");

From 004570a377b2df355064d48afc54375690c3cdb0 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Tue, 16 Jun 2020 15:14:11 -0400
Subject: [PATCH 04/15] Add HTTP responses to FileTransferErrors

---
 src/libstore/filetransfer.cc | 26 ++++++++++++++++++++------
 src/libstore/filetransfer.hh |  5 +++--
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index 9566e0ae9..d89f8388f 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -122,7 +122,7 @@ struct curlFileTransfer : public FileTransfer
             if (requestHeaders) curl_slist_free_all(requestHeaders);
             try {
                 if (!done)
-                    fail(FileTransferError(Interrupted, "download of '%s' was interrupted", request.uri));
+                    fail(FileTransferError(Interrupted, nullptr, "download of '%s' was interrupted", request.uri));
             } catch (...) {
                 ignoreException();
             }
@@ -152,8 +152,18 @@ struct curlFileTransfer : public FileTransfer
                 size_t realSize = size * nmemb;
                 result.bodySize += realSize;
 
-                if (!decompressionSink)
+                if (!decompressionSink) {
                     decompressionSink = makeDecompressionSink(encoding, finalSink);
+                    if (! successfulStatuses.count(getHTTPStatus())) {
+                        // In this case we want to construct a TeeSink, to keep
+                        // the response around (which we figure won't be big
+                        // like an actual download should be) to improve error
+                        // messages.
+                        decompressionSink = std::make_shared<TeeSink<ref<CompressionSink>>>(
+                            ref<CompressionSink>{ decompressionSink }
+                        );
+                    }
+                }
 
                 (*decompressionSink)((unsigned char *) contents, realSize);
 
@@ -408,16 +418,20 @@ struct curlFileTransfer : public FileTransfer
 
                 attempt++;
 
+                std::shared_ptr<std::string> response;
+                if (decompressionSink)
+                    if (auto teeSink = std::dynamic_pointer_cast<TeeSink<std::shared_ptr<CompressionSink>>>(decompressionSink))
+                        response = teeSink->data;
                 auto exc =
                     code == CURLE_ABORTED_BY_CALLBACK && _isInterrupted
-                    ? FileTransferError(Interrupted, fmt("%s of '%s' was interrupted", request.verb(), request.uri))
+                    ? FileTransferError(Interrupted, response, fmt("%s of '%s' was interrupted", request.verb(), request.uri))
                     : httpStatus != 0
-                    ? FileTransferError(err,
+                    ? FileTransferError(err, response,
                         fmt("unable to %s '%s': HTTP error %d",
                             request.verb(), request.uri, httpStatus)
                         + (code == CURLE_OK ? "" : fmt(" (curl error: %s)", curl_easy_strerror(code)))
                         )
-                    : FileTransferError(err,
+                    : FileTransferError(err, response,
                         fmt("unable to %s '%s': %s (%d)",
                             request.verb(), request.uri, curl_easy_strerror(code), code));
 
@@ -675,7 +689,7 @@ struct curlFileTransfer : public FileTransfer
                 auto s3Res = s3Helper.getObject(bucketName, key);
                 FileTransferResult res;
                 if (!s3Res.data)
-                    throw FileTransferError(NotFound, fmt("S3 object '%s' does not exist", request.uri));
+                    throw FileTransferError(NotFound, nullptr, fmt("S3 object '%s' does not exist", request.uri));
                 res.data = s3Res.data;
                 callback(std::move(res));
 #else
diff --git a/src/libstore/filetransfer.hh b/src/libstore/filetransfer.hh
index 11dca2fe0..8e31a9e42 100644
--- a/src/libstore/filetransfer.hh
+++ b/src/libstore/filetransfer.hh
@@ -103,9 +103,10 @@ class FileTransferError : public Error
 {
 public:
     FileTransfer::Error error;
+    std::shared_ptr<string> response; // intentionally optional
     template<typename... Args>
-    FileTransferError(FileTransfer::Error error, const Args & ... args)
-        : Error(args...), error(error)
+    FileTransferError(FileTransfer::Error error, std::shared_ptr<string> response, const Args & ... args)
+        : Error(args...), error(error), response(response)
     { }
 };
 

From 74b219ef6e5e171c56c8ad7385969e0d0df09ed8 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 18 Jun 2020 14:48:45 +0000
Subject: [PATCH 05/15] Adjust FileTransferError message to use opt response

---
 src/libstore/filetransfer.cc | 12 ++++++++++++
 src/libstore/filetransfer.hh |  7 ++++---
 src/libutil/error.hh         |  3 +--
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index d89f8388f..fa8ad33f5 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -834,6 +834,18 @@ void FileTransfer::download(FileTransferRequest && request, Sink & sink)
     }
 }
 
+template<typename... Args>
+FileTransferError::FileTransferError(FileTransfer::Error error, std::shared_ptr<string> response, const Args & ... args)
+    : Error(args...), error(error), response(response)
+{
+    const auto hf = hintfmt(args...);
+    if (response) {
+        err.hint = hintfmt("%1%\n\nresponse body:\n\n%2%", normaltxt(hf.str()), response);
+    } else {
+        err.hint = hf;
+    }
+}
+
 bool isUri(const string & s)
 {
     if (s.compare(0, 8, "channel:") == 0) return true;
diff --git a/src/libstore/filetransfer.hh b/src/libstore/filetransfer.hh
index 8e31a9e42..25ade0add 100644
--- a/src/libstore/filetransfer.hh
+++ b/src/libstore/filetransfer.hh
@@ -104,10 +104,11 @@ class FileTransferError : public Error
 public:
     FileTransfer::Error error;
     std::shared_ptr<string> response; // intentionally optional
+
     template<typename... Args>
-    FileTransferError(FileTransfer::Error error, std::shared_ptr<string> response, const Args & ... args)
-        : Error(args...), error(error), response(response)
-    { }
+    FileTransferError(FileTransfer::Error error, std::shared_ptr<string> response, const Args & ... args);
+
+    virtual const char* sname() const override { return "FileTransferError"; }
 };
 
 bool isUri(const string & s);
diff --git a/src/libutil/error.hh b/src/libutil/error.hh
index 1e6102ce1..ac9d2e494 100644
--- a/src/libutil/error.hh
+++ b/src/libutil/error.hh
@@ -173,9 +173,8 @@ public:
 
     template<typename... Args>
     SysError(const Args & ... args)
-      :Error("")
+        : Error(""), errNo(errno)
     {
-        errNo = errno;
         auto hf = hintfmt(args...);
         err.hint = hintfmt("%1%: %2%", normaltxt(hf.str()), strerror(errNo));
     }

From 639e20dc3ed9c5b28138285653912de78fe0507f Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 18 Jun 2020 17:54:16 +0000
Subject: [PATCH 06/15] Prevent '%' in URL from causing crashes

We have a larger problem that passsing computed strings to the first
variable argument of many exception constructors is unsafe because that
first variable argument is interpreted not as a plain string, but format
string, and if it contains '%' boost::format will abort, since there are
no arguments to the format string.

In this particular instance '%' was used as part of an escape code in a
URL, which, when the download failed, caused Nix to abort displaying the
`FileTransferError`.
---
 src/libstore/filetransfer.cc | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index 531b85af8..e795da860 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -410,16 +410,13 @@ struct curlFileTransfer : public FileTransfer
 
                 auto exc =
                     code == CURLE_ABORTED_BY_CALLBACK && _isInterrupted
-                    ? FileTransferError(Interrupted, fmt("%s of '%s' was interrupted", request.verb(), request.uri))
+                    ? FileTransferError(Interrupted, "%s of '%s' was interrupted", request.verb(), request.uri)
                     : httpStatus != 0
-                    ? FileTransferError(err,
-                        fmt("unable to %s '%s': HTTP error %d",
-                            request.verb(), request.uri, httpStatus)
-                        + (code == CURLE_OK ? "" : fmt(" (curl error: %s)", curl_easy_strerror(code)))
-                        )
-                    : FileTransferError(err,
-                        fmt("unable to %s '%s': %s (%d)",
-                            request.verb(), request.uri, curl_easy_strerror(code), code));
+                    ? FileTransferError(err, "unable to %s '%s': HTTP error %d%s",
+                        request.verb(), request.uri, httpStatus,
+                        code == CURLE_OK ? "" : fmt(" (curl error: %s)", curl_easy_strerror(code)))
+                    : FileTransferError(err, "unable to %s '%s': %s (%d)",
+                        request.verb(), request.uri, curl_easy_strerror(code), code);
 
                 /* If this is a transient error, then maybe retry the
                    download after a while. If we're writing to a
@@ -675,7 +672,7 @@ struct curlFileTransfer : public FileTransfer
                 auto s3Res = s3Helper.getObject(bucketName, key);
                 FileTransferResult res;
                 if (!s3Res.data)
-                    throw FileTransferError(NotFound, fmt("S3 object '%s' does not exist", request.uri));
+                    throw FileTransferError(NotFound, "S3 object '%s' does not exist", request.uri);
                 res.data = s3Res.data;
                 callback(std::move(res));
 #else

From 1b23fe4afb8ed2c41604a1ed19cf3d49c34f46d1 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 18 Jun 2020 19:03:10 +0000
Subject: [PATCH 07/15] Fix bugs

 - Bad dynamic cast target ...classic

 - std::shared_ptr need explicit deref
---
 src/libstore/filetransfer.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index 9ae682bbb..8b66cbdad 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -420,7 +420,7 @@ struct curlFileTransfer : public FileTransfer
 
                 std::shared_ptr<std::string> response;
                 if (decompressionSink)
-                    if (auto teeSink = std::dynamic_pointer_cast<TeeSink<std::shared_ptr<CompressionSink>>>(decompressionSink))
+                    if (auto teeSink = std::dynamic_pointer_cast<TeeSink<ref<CompressionSink>>>(decompressionSink))
                         response = teeSink->data;
                 auto exc =
                     code == CURLE_ABORTED_BY_CALLBACK && _isInterrupted
@@ -837,7 +837,7 @@ FileTransferError::FileTransferError(FileTransfer::Error error, std::shared_ptr<
 {
     const auto hf = hintfmt(args...);
     if (response) {
-        err.hint = hintfmt("%1%\n\nresponse body:\n\n%2%", normaltxt(hf.str()), response);
+        err.hint = hintfmt("%1%\n\nresponse body:\n\n%2%", normaltxt(hf.str()), *response);
     } else {
         err.hint = hf;
     }

From e197bc622948973fca192774b6cd8e0d3157aeb6 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Tue, 23 Jun 2020 11:12:01 -0400
Subject: [PATCH 08/15] Enable the --store option to take relative paths

In nix commands which accept --store options, we can now specify a
relative path, which will be canonicalized.
---
 src/libstore/store-api.cc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index e4a4ae11e..42ffa3ddb 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -864,7 +864,7 @@ StoreType getStoreType(const std::string & uri, const std::string & stateDir)
 {
     if (uri == "daemon") {
         return tDaemon;
-    } else if (uri == "local" || hasPrefix(uri, "/")) {
+    } else if (uri == "local" || hasPrefix(uri, "/") || hasPrefix(uri, "./")) {
         return tLocal;
     } else if (uri == "" || uri == "auto") {
         if (access(stateDir.c_str(), R_OK | W_OK) == 0)
@@ -888,8 +888,11 @@ static RegisterStoreImplementation regStore([](
             return std::shared_ptr<Store>(std::make_shared<UDSRemoteStore>(params));
         case tLocal: {
             Store::Params params2 = params;
-            if (hasPrefix(uri, "/"))
+            if (hasPrefix(uri, "/")) {
                 params2["root"] = uri;
+            } else if (hasPrefix(uri, "./")) {
+                params2["root"] = absPath(uri);
+            }
             return std::shared_ptr<Store>(std::make_shared<LocalStore>(params2));
         }
         default:

From 4178f36a1d4005a78a024c60d1f024c6ecccf8e8 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Fri, 17 Jul 2020 15:50:53 -0400
Subject: [PATCH 09/15] Test relative store paths

---
 tests/local-store.sh | 20 ++++++++++++++++++++
 tests/local.mk       |  2 +-
 2 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 tests/local-store.sh

diff --git a/tests/local-store.sh b/tests/local-store.sh
new file mode 100644
index 000000000..4ec3d64b0
--- /dev/null
+++ b/tests/local-store.sh
@@ -0,0 +1,20 @@
+source common.sh
+
+cd $TEST_ROOT
+
+echo example > example.txt
+mkdir -p ./x
+
+NIX_STORE_DIR=$TEST_ROOT/x
+
+CORRECT_PATH=$(nix-store --store ./x --add example.txt)
+
+PATH1=$(nix path-info --store ./x $CORRECT_PATH)
+[ $CORRECT_PATH == $PATH1 ]
+
+PATH2=$(nix path-info --store "$PWD/x" $CORRECT_PATH)
+[ $CORRECT_PATH == $PATH2 ]
+
+# FIXME we could also test the query parameter version:
+# PATH3=$(nix path-info --store "local?store=$PWD/x" $CORRECT_PATH)
+# [ $CORRECT_PATH == $PATH3 ]
diff --git a/tests/local.mk b/tests/local.mk
index 81366160b..0f3bfe606 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -6,7 +6,7 @@ nix_tests = \
   gc-auto.sh \
   referrers.sh user-envs.sh logging.sh nix-build.sh misc.sh fixed.sh \
   gc-runtime.sh check-refs.sh filter-source.sh \
-  remote-store.sh export.sh export-graph.sh \
+  local-store.sh remote-store.sh export.sh export-graph.sh \
   timeout.sh secure-drv-outputs.sh nix-channel.sh \
   multiple-outputs.sh import-derivation.sh fetchurl.sh optimise-store.sh \
   binary-cache.sh nix-profile.sh repair.sh dump-db.sh case-hack.sh \

From 0ca9744694a5294e995fcddc11f5f195c84036a4 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Mon, 20 Jul 2020 15:56:52 -0400
Subject: [PATCH 10/15] Use heuristics to decide when to show the response

Due to https://github.com/NixOS/nix/issues/3841 we don't know how print
different messages for different verbosity levels.
---
 src/libstore/filetransfer.cc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index 4d35bd2b5..4149f8155 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -845,8 +845,11 @@ FileTransferError::FileTransferError(FileTransfer::Error error, std::shared_ptr<
     : Error(args...), error(error), response(response)
 {
     const auto hf = hintfmt(args...);
-    if (response) {
-        err.hint = hintfmt("%1%\n\nresponse body:\n\n%2%", normaltxt(hf.str()), *response);
+    // FIXME: Due to https://github.com/NixOS/nix/issues/3841 we don't know how
+    // to print different messages for different verbosity levels. For now
+    // we add some heuristics for detecting when we want to show the response.
+    if (response && (response->size() < 1024 || response->find("<html>") != string::npos)) {
+            err.hint = hintfmt("%1%\n\nresponse body:\n\n%2%", normaltxt(hf.str()), *response);
     } else {
         err.hint = hf;
     }

From 922a845ffc4eaa51797bc376d237c6216f0d8391 Mon Sep 17 00:00:00 2001
From: Carlo Nucera <carlo.nucera@protonmail.com>
Date: Tue, 21 Jul 2020 10:24:19 -0400
Subject: [PATCH 11/15] Update chunkSize to the suggested value

This was a suggested course of action in a review in one of our earlier
commits, https://github.com/NixOS/nix/pull/3801#discussion_r457557079
---
 src/libstore/local-store.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 340fb5306..9ea71170f 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -1069,7 +1069,7 @@ StorePath LocalStore::addToStoreFromDump(Source & source0, const string & name,
        or the original source is empty */
     while (dump.size() < settings.narBufferSize) {
         auto oldSize = dump.size();
-        constexpr size_t chunkSize = 1024;
+        constexpr size_t chunkSize = 65536;
         auto want = std::min(chunkSize, settings.narBufferSize - oldSize);
         dump.resize(oldSize + want);
         auto got = 0;

From 6cce32c8e8b9559f197f6d3e8814796cfc490582 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 21 Jul 2020 15:39:47 +0000
Subject: [PATCH 12/15] Change logic for deciding what is a relative path for
 the local store

The was Eelco's prefered logic, and it looks good to me!
---
 src/libstore/store-api.cc | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index d37e970df..67ce6e66c 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -914,12 +914,20 @@ ref<Store> openStore(const std::string & uri_,
     throw Error("don't know how to open Nix store '%s'", uri);
 }
 
+static bool isNonUriPath(const std::string & spec) {
+    return
+        // is not a URL
+        spec.find("://") == std::string::npos
+        // Has at least one path separator, and so isn't a single word that
+        // might be special like "auto"
+        && spec.find("/") != std::string::npos;
+}
 
 StoreType getStoreType(const std::string & uri, const std::string & stateDir)
 {
     if (uri == "daemon") {
         return tDaemon;
-    } else if (uri == "local" || hasPrefix(uri, "/") || hasPrefix(uri, "./")) {
+    } else if (uri == "local" || isNonUriPath(uri)) {
         return tLocal;
     } else if (uri == "" || uri == "auto") {
         if (access(stateDir.c_str(), R_OK | W_OK) == 0)
@@ -943,9 +951,7 @@ static RegisterStoreImplementation regStore([](
             return std::shared_ptr<Store>(std::make_shared<UDSRemoteStore>(params));
         case tLocal: {
             Store::Params params2 = params;
-            if (hasPrefix(uri, "/")) {
-                params2["root"] = uri;
-            } else if (hasPrefix(uri, "./")) {
+            if (isNonUriPath(uri)) {
                 params2["root"] = absPath(uri);
             }
             return std::shared_ptr<Store>(std::make_shared<LocalStore>(params2));

From ae9e9753ce9100ac8ac98fb76d4ac9de45b5734c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Josef=20Kemetm=C3=BCller?= <josef.kemetmueller@gmail.com>
Date: Wed, 22 Jul 2020 13:45:15 +0200
Subject: [PATCH 13/15] README: Fix link to hacking guide

The link was previously interpreted as if it were relative to the current file.
---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index e5f7a694f..03c5deb7b 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ Information on additional installation methods is available on the [Nix download
 
 ## Building And Developing
 
-See our [Hacking guide](hydra.nixos.org/job/nix/master/build.x86_64-linux/latest/download-by-type/doc/manual#chap-hacking) in our manual for instruction on how to
+See our [Hacking guide](https://hydra.nixos.org/job/nix/master/build.x86_64-linux/latest/download-by-type/doc/manual#chap-hacking) in our manual for instruction on how to
 build nix from source with nix-build or how to get a development environment.
 
 ## Additional Resources

From c56356baccbf006c7835afa9ce58012631e90b31 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Wed, 22 Jul 2020 21:37:54 +0000
Subject: [PATCH 14/15] Separate concerns in `scanForReferences` with TeeSink

This also will make it easier to use a `HashModuloSink` instead for CA
derivations.
---
 src/libstore/references.cc | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/src/libstore/references.cc b/src/libstore/references.cc
index a10d536a3..968e2e425 100644
--- a/src/libstore/references.cc
+++ b/src/libstore/references.cc
@@ -48,13 +48,12 @@ static void search(const unsigned char * s, size_t len,
 
 struct RefScanSink : Sink
 {
-    HashSink hashSink;
     StringSet hashes;
     StringSet seen;
 
     string tail;
 
-    RefScanSink() : hashSink(htSHA256) { }
+    RefScanSink() { }
 
     void operator () (const unsigned char * data, size_t len);
 };
@@ -62,8 +61,6 @@ struct RefScanSink : Sink
 
 void RefScanSink::operator () (const unsigned char * data, size_t len)
 {
-    hashSink(data, len);
-
     /* It's possible that a reference spans the previous and current
        fragment, so search in the concatenation of the tail of the
        previous fragment and the start of the current fragment. */
@@ -82,7 +79,9 @@ void RefScanSink::operator () (const unsigned char * data, size_t len)
 PathSet scanForReferences(const string & path,
     const PathSet & refs, HashResult & hash)
 {
-    RefScanSink sink;
+    RefScanSink refsSink;
+    HashSink hashSink { htSHA256 };
+    TeeSink sink { refsSink, hashSink };
     std::map<string, Path> backMap;
 
     /* For efficiency (and a higher hit rate), just search for the
@@ -97,7 +96,7 @@ PathSet scanForReferences(const string & path,
         assert(s.size() == refLength);
         assert(backMap.find(s) == backMap.end());
         // parseHash(htSHA256, s);
-        sink.hashes.insert(s);
+        refsSink.hashes.insert(s);
         backMap[s] = i;
     }
 
@@ -106,13 +105,13 @@ PathSet scanForReferences(const string & path,
 
     /* Map the hashes found back to their store paths. */
     PathSet found;
-    for (auto & i : sink.seen) {
+    for (auto & i : refsSink.seen) {
         std::map<string, Path>::iterator j;
         if ((j = backMap.find(i)) == backMap.end()) abort();
         found.insert(j->second);
     }
 
-    hash = sink.hashSink.finish();
+    hash = hashSink.finish();
 
     return found;
 }

From b9ead08ca8f3b8e693a4528d0c6f642dcee026fe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fabian=20M=C3=B6ller?= <fabianm88@gmail.com>
Date: Thu, 23 Jul 2020 14:21:27 +0200
Subject: [PATCH 15/15] Save changes made by "nix registry pin" to user
 registry

---
 src/nix/registry.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/nix/registry.cc b/src/nix/registry.cc
index 16d7e511f..ebee4545c 100644
--- a/src/nix/registry.cc
+++ b/src/nix/registry.cc
@@ -111,6 +111,7 @@ struct CmdRegistryPin : virtual Args, EvalCommand
         fetchers::Attrs extraAttrs;
         if (ref.subdir != "") extraAttrs["dir"] = ref.subdir;
         userRegistry->add(ref.input, resolved, extraAttrs);
+        userRegistry->write(fetchers::getUserRegistryPath());
     }
 };