Merge remote-tracking branch 'origin/master' into flakes

4 files changed, 111 insertions, 36 deletions

diff --git a/src/libutil/compression.cc b/src/libutil/compression.cc
index 0dd84e320..860b04adb 100644
--- a/src/libutil/compression.cc
+++ b/src/libutil/compression.cc
@@ -11,6 +11,8 @@
 #include <brotli/decode.h>
 #include <brotli/encode.h>
 
+#include <zlib.h>
+
 #include <iostream>
 
 namespace nix {
@@ -42,6 +44,66 @@ struct NoneSink : CompressionSink
     void write(const unsigned char * data, size_t len) override { nextSink(data, len); }
 };
 
+struct GzipDecompressionSink : CompressionSink
+{
+    Sink & nextSink;
+    z_stream strm;
+    bool finished = false;
+    uint8_t outbuf[BUFSIZ];
+
+    GzipDecompressionSink(Sink & nextSink) : nextSink(nextSink)
+    {
+        strm.zalloc = Z_NULL;
+        strm.zfree = Z_NULL;
+        strm.opaque = Z_NULL;
+        strm.avail_in = 0;
+        strm.next_in = Z_NULL;
+        strm.next_out = outbuf;
+        strm.avail_out = sizeof(outbuf);
+
+        // Enable gzip and zlib decoding (+32) with 15 windowBits
+        int ret = inflateInit2(&strm,15+32);
+        if (ret != Z_OK)
+            throw CompressionError("unable to initialise gzip encoder");
+    }
+
+    ~GzipDecompressionSink()
+    {
+        inflateEnd(&strm);
+    }
+
+    void finish() override
+    {
+        CompressionSink::flush();
+        write(nullptr, 0);
+    }
+
+    void write(const unsigned char * data, size_t len) override
+    {
+        assert(len <= std::numeric_limits<decltype(strm.avail_in)>::max());
+
+        strm.next_in = (Bytef *) data;
+        strm.avail_in = len;
+
+        while (!finished && (!data || strm.avail_in)) {
+            checkInterrupt();
+
+            int ret = inflate(&strm,Z_SYNC_FLUSH);
+            if (ret != Z_OK && ret != Z_STREAM_END)
+                throw CompressionError("error while decompressing gzip file: %d (%d, %d)",
+                    zError(ret), len, strm.avail_in);
+
+            finished = ret == Z_STREAM_END;
+
+            if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) {
+                nextSink(outbuf, sizeof(outbuf) - strm.avail_out);
+                strm.next_out = (Bytef *) outbuf;
+                strm.avail_out = sizeof(outbuf);
+            }
+        }
+    }
+};
+
 struct XzDecompressionSink : CompressionSink
 {
     Sink & nextSink;
@@ -215,6 +277,8 @@ ref<CompressionSink> makeDecompressionSink(const std::string & method, Sink & ne
         return make_ref<XzDecompressionSink>(nextSink);
     else if (method == "bzip2")
         return make_ref<BzipDecompressionSink>(nextSink);
+    else if (method == "gzip")
+        return make_ref<GzipDecompressionSink>(nextSink);
     else if (method == "br")
         return make_ref<BrotliDecompressionSink>(nextSink);
     else
diff --git a/src/libutil/rust-ffi.cc b/src/libutil/rust-ffi.cc
index accc5e22b..8b8b7b75d 100644
--- a/src/libutil/rust-ffi.cc
+++ b/src/libutil/rust-ffi.cc
@@ -3,10 +3,14 @@
 
 extern "C" std::exception_ptr * make_error(rust::StringSlice s)
 {
-    // FIXME: leak
     return new std::exception_ptr(std::make_exception_ptr(nix::Error(std::string(s.ptr, s.size))));
 }
 
+extern "C" void destroy_error(std::exception_ptr * ex)
+{
+    free(ex);
+}
+
 namespace rust {
 
 std::ostream & operator << (std::ostream & str, const String & s)
@@ -15,4 +19,15 @@ std::ostream & operator << (std::ostream & str, const String & s)
     return str;
 }
 
+size_t Source::sourceWrapper(void * _this, rust::Slice<uint8_t> data)
+{
+    try {
+        // FIXME: how to propagate exceptions?
+        auto n = ((nix::Source *) _this)->read((unsigned char *) data.ptr, data.size);
+        return n;
+    } catch (...) {
+        abort();
+    }
+}
+
 }
diff --git a/src/libutil/rust-ffi.hh b/src/libutil/rust-ffi.hh
index a77f83ac5..3b51661c2 100644
--- a/src/libutil/rust-ffi.hh
+++ b/src/libutil/rust-ffi.hh
@@ -140,64 +140,58 @@ struct Source
         : fun(sourceWrapper), _this(&_this)
     {}
 
-    // FIXME: how to propagate exceptions?
-    static size_t sourceWrapper(void * _this, rust::Slice<uint8_t> data)
-    {
-        auto n = ((nix::Source *) _this)->read((unsigned char *) data.ptr, data.size);
-        return n;
-    }
+    static size_t sourceWrapper(void * _this, rust::Slice<uint8_t> data);
 };
 
 /* C++ representation of Rust's Result<T, CppException>. */
 template<typename T>
 struct Result
 {
-    unsigned int tag;
+    enum { Ok = 0, Err = 1, Uninit = 2 } tag;
 
     union {
         T data;
         std::exception_ptr * exc;
     };
 
+    Result() : tag(Uninit) { }; // FIXME: remove
+
+    Result(const Result &) = delete;
+
+    Result(Result && other)
+        : tag(other.tag)
+    {
+        other.tag = Uninit;
+        if (tag == Ok)
+            data = std::move(other.data);
+        else if (tag == Err)
+            exc = other.exc;
+    }
+
     ~Result()
     {
-        if (tag == 0)
+        if (tag == Ok)
             data.~T();
-        else if (tag == 1)
-            // FIXME: don't leak exc
+        else if (tag == Err)
+            free(exc);
+        else if (tag == Uninit)
             ;
+        else
+            abort();
     }
 
     /* Rethrow the wrapped exception or return the wrapped value. */
     T unwrap()
     {
-        if (tag == 0)
+        if (tag == Ok) {
+            tag = Uninit;
             return std::move(data);
-        else if (tag == 1)
+        }
+        else if (tag == Err)
             std::rethrow_exception(*exc);
         else
             abort();
     }
 };
 
-template<typename T>
-struct CBox
-{
-    T * ptr;
-
-    T * operator ->()
-    {
-        return ptr;
-    }
-
-    CBox(T * ptr) : ptr(ptr) { }
-    CBox(const CBox &) = delete;
-    CBox(CBox &&) = delete;
-
-    ~CBox()
-    {
-        free(ptr);
-    }
-};
-
 }
diff --git a/src/libutil/tarfile.cc b/src/libutil/tarfile.cc
index 262bc655f..1be0ba24c 100644
--- a/src/libutil/tarfile.cc
+++ b/src/libutil/tarfile.cc
@@ -3,7 +3,7 @@
 
 extern "C" {
     rust::Result<std::tuple<>> *
-    unpack_tarfile(rust::Source source, rust::StringSlice dest_dir);
+    unpack_tarfile(rust::Source source, rust::StringSlice dest_dir, rust::Result<std::tuple<>> & out);
 }
 
 namespace nix {
@@ -11,7 +11,9 @@ namespace nix {
 void unpackTarfile(Source & source, const Path & destDir)
 {
     rust::Source source2(source);
-    rust::CBox(unpack_tarfile(source2, destDir))->unwrap();
+    rust::Result<std::tuple<>> res;
+    unpack_tarfile(source2, destDir, res);
+    res.unwrap();
 }
 
 void unpackTarfile(const Path & tarFile, const Path & destDir,
@@ -22,8 +24,8 @@ void unpackTarfile(const Path & tarFile, const Path & destDir,
     auto source = sinkToSource([&](Sink & sink) {
         // FIXME: look at first few bytes to determine compression type.
         auto decompressor =
-            // FIXME: add .gz support
             hasSuffix(*baseName, ".bz2") ? makeDecompressionSink("bzip2", sink) :
+            hasSuffix(*baseName, ".gz") ? makeDecompressionSink("gzip", sink) :
             hasSuffix(*baseName, ".xz") ? makeDecompressionSink("xz", sink) :
             makeDecompressionSink("none", sink);
         readFile(tarFile, *decompressor);