Merge "Merge branch android10-qpr3-release" into android10-gsiandroid10-gsi

2 files changed, 84 insertions, 0 deletions

diff --git a/Android.bp b/Android.bp
index c8fe151..2bc5269 100644
--- a/Android.bp
+++ b/Android.bp
@@ -194,6 +194,24 @@ cc_binary_host {
     },
 }
 
+cc_binary_host {
+    name: "lld",
+    srcs: ["lld_main.cpp"],
+    ldflags: ["-static"],
+    stl: "libc++_static",
+    target: {
+        darwin: {
+            enabled: false,
+        },
+        linux: {
+            enabled: false,
+        },
+        windows: {
+            enabled: true,
+        },
+    },
+}
+
 subdirs = [
     "BitWriter_2_9",
     "BitWriter_2_9_func",
diff --git a/lld_main.cpp b/lld_main.cpp
new file mode 100644
index 0000000..dc095bd
--- /dev/null
+++ b/lld_main.cpp
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2020, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <cstdio>
+#include <cstdlib>
+#include <string>
+#include <vector>
+#include <unistd.h>
+
+int main(int argc, const char **argv) {
+  // Create a copy of argv strings that we can modify, and then eventually
+  // const_cast away the const-ness of the buffers to call execv().
+  std::vector<std::unique_ptr<std::string>> argv_strings;
+  std::vector<const char *> argv_chars;
+
+  // Replace lld.exe with lld-bin\lld.exe instead on Windows.
+  argv_strings.push_back(std::make_unique<std::string>(argv[0]));
+  size_t idx = argv_strings[0]->rfind("lld.exe");
+  argv_strings[0]->insert(idx, "lld-bin\\");
+  argv_chars.push_back(argv_strings[0]->c_str());
+
+  // Make a copy of every other argv entry, and map a pointer to the C string
+  // buffer as argv_chars for use with execv() later.
+  for (int i = 1; i < argc; ++i) {
+    argv_strings.push_back(std::make_unique<std::string>(argv[i]));
+    argv_chars.push_back(argv_strings[i]->c_str());
+  }
+
+  // execv() expects a nullptr to terminate the argument list for argv.
+  argv_chars.push_back(nullptr);
+
+  // We cast away the const-ness of the char buffers, but it should be safe,
+  // since we own these strings.
+  int status = execv(argv_chars[0], const_cast<char **>(argv_chars.data()));
+
+  // We shouldn't get here unless we failed to execute the new binary.
+  if (status != 0) {
+    std::string command;
+    bool first = true;
+    for (auto arg : argv_chars) {
+      if (arg) {
+        if (!first) {
+          command.append(" ");
+        } else {
+          first = false;
+        }
+        command.append(arg);
+      }
+    }
+    fprintf(stderr, "Failed to execute command: %s\n", command.c_str());
+  }
+  return status;
+}