protobuf.patch

# https://github.com/protocolbuffers/protobuf/pull/6720
diff --git a/third_party/BUILD b/third_party/BUILD
new file mode 100644
index 0000000000..b66101a39a
--- /dev/null
+++ b/third_party/BUILD
@@ -0,0 +1 @@
+exports_files(["six.BUILD", "zlib.BUILD"])

# https://github.com/protocolbuffers/protobuf/pull/6896
diff --git a/src/google/protobuf/stubs/strutil.cc b/src/google/protobuf/stubs/strutil.cc
index 62b3f0a871..bb3df47ccf 100644
--- a/src/google/protobuf/stubs/strutil.cc
+++ b/src/google/protobuf/stubs/strutil.cc
@@ -1435,32 +1435,44 @@ AlphaNum::AlphaNum(strings::Hex hex) {
 // after the area just overwritten.  It comes in multiple flavors to minimize
 // call overhead.
 static char *Append1(char *out, const AlphaNum &x) {
-  memcpy(out, x.data(), x.size());
-  return out + x.size();
+  if (x.size() > 0) {
+    memcpy(out, x.data(), x.size());
+    out += x.size();
+  }
+  return out;
 }
 
 static char *Append2(char *out, const AlphaNum &x1, const AlphaNum &x2) {
-  memcpy(out, x1.data(), x1.size());
-  out += x1.size();
-
-  memcpy(out, x2.data(), x2.size());
-  return out + x2.size();
+  if (x1.size() > 0) {
+    memcpy(out, x1.data(), x1.size());
+    out += x1.size();
+  }
+  if (x2.size() > 0) {
+    memcpy(out, x2.data(), x2.size());
+    out += x2.size();
+  }
+  return out;
 }
 
-static char *Append4(char *out,
-                     const AlphaNum &x1, const AlphaNum &x2,
+static char *Append4(char *out, const AlphaNum &x1, const AlphaNum &x2,
                      const AlphaNum &x3, const AlphaNum &x4) {
-  memcpy(out, x1.data(), x1.size());
-  out += x1.size();
-
-  memcpy(out, x2.data(), x2.size());
-  out += x2.size();
-
-  memcpy(out, x3.data(), x3.size());
-  out += x3.size();
-
-  memcpy(out, x4.data(), x4.size());
-  return out + x4.size();
+  if (x1.size() > 0) {
+    memcpy(out, x1.data(), x1.size());
+    out += x1.size();
+  }
+  if (x2.size() > 0) {
+    memcpy(out, x2.data(), x2.size());
+    out += x2.size();
+  }
+  if (x3.size() > 0) {
+    memcpy(out, x3.data(), x3.size());
+    out += x3.size();
+  }
+  if (x4.size() > 0) {
+    memcpy(out, x4.data(), x4.size());
+    out += x4.size();
+  }
+  return out;
 }
 
 string StrCat(const AlphaNum &a, const AlphaNum &b) {

# patching for zlib binding
diff --git a/BUILD b/BUILD
index efc3d8e7f..746ad4851 100644
--- a/BUILD
+++ b/BUILD
@@ -24,7 +24,7 @@ config_setting(
 # ZLIB configuration
 ################################################################################

-ZLIB_DEPS = ["@zlib//:zlib"]
+ZLIB_DEPS = ["//external:zlib"]

 ################################################################################
 # Protobuf Runtime Library

diff --git a/protobuf.bzl b/protobuf.bzl
index 5fa5543b1..484bc41a7 100644
--- a/protobuf.bzl
+++ b/protobuf.bzl
@@ -75,18 +75,17 @@ def _RelativeOutputPath(path, include, dest = ""):
 def _proto_gen_impl(ctx):
     """General implementation for generating protos"""
     srcs = ctx.files.srcs
-    deps = []
-    deps += ctx.files.srcs
+    deps = depset(direct=ctx.files.srcs)
     source_dir = _SourceDir(ctx)
     gen_dir = _GenDir(ctx).rstrip("/")
     if source_dir:
-        import_flags = ["-I" + source_dir, "-I" + gen_dir]
+        import_flags = depset(direct=["-I" + source_dir, "-I" + gen_dir])
     else:
-        import_flags = ["-I."]
+        import_flags = depset(direct=["-I."])
 
     for dep in ctx.attr.deps:
-        import_flags += dep.proto.import_flags
-        deps += dep.proto.deps
+        import_flags = depset(transitive=[import_flags, dep.proto.import_flags])
+        deps = depset(transitive=[deps, dep.proto.deps])
 
     if not ctx.attr.gen_cc and not ctx.attr.gen_py and not ctx.executable.plugin:
         return struct(
@@ -103,7 +102,7 @@ def _proto_gen_impl(ctx):
         in_gen_dir = src.root.path == gen_dir
         if in_gen_dir:
             import_flags_real = []
-            for f in depset(import_flags).to_list():
+            for f in import_flags.to_list():
                 path = f.replace("-I", "")
                 import_flags_real.append("-I$(realpath -s %s)" % path)
 
@@ -118,7 +117,7 @@ def _proto_gen_impl(ctx):
             outs.extend(_PyOuts([src.basename], use_grpc_plugin = use_grpc_plugin))
 
         outs = [ctx.actions.declare_file(out, sibling = src) for out in outs]
-        inputs = [src] + deps
+        inputs = [src] + deps.to_list()
         tools = [ctx.executable.protoc]
         if ctx.executable.plugin:
             plugin = ctx.executable.plugin
@@ -141,7 +140,7 @@ def _proto_gen_impl(ctx):
                 inputs = inputs,
                 tools = tools,
                 outputs = outs,
-                arguments = args + import_flags + [src.path],
+                arguments = args + import_flags.to_list() + [src.path],
                 executable = ctx.executable.protoc,
                 mnemonic = "ProtoCompile",
                 use_default_shell_env = True,