Added cmd_fuzzer

Test: ./cmd_fuzzer
Bug: 187131591

Change-Id: Iac91b398366135bd87074881d3800c535e1dfc5f
diff --git a/cmds/cmd/fuzzer/cmd_fuzzer.cpp b/cmds/cmd/fuzzer/cmd_fuzzer.cpp
new file mode 100644
index 0000000..ab514a1
--- /dev/null
+++ b/cmds/cmd/fuzzer/cmd_fuzzer.cpp
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2021 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 <binder/TextOutput.h>
+#include <cmd.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string>
+#include <vector>
+
+#include <fuzzer/FuzzedDataProvider.h>
+
+using namespace std;
+using namespace android;
+
+class TestTextOutput : public TextOutput {
+public:
+    TestTextOutput() {}
+    virtual ~TestTextOutput() {}
+
+    virtual status_t print(const char* /*txt*/, size_t /*len*/) { return NO_ERROR; }
+    virtual void moveIndent(int /*delta*/) { return; }
+    virtual void pushBundle() { return; }
+    virtual void popBundle() { return; }
+};
+
+class CmdFuzzer {
+public:
+    void process(const uint8_t* data, size_t size);
+
+private:
+    FuzzedDataProvider* mFDP = nullptr;
+};
+
+void CmdFuzzer::process(const uint8_t* data, size_t size) {
+    mFDP = new FuzzedDataProvider(data, size);
+    vector<string> arguments;
+    if (mFDP->ConsumeBool()) {
+        if (mFDP->ConsumeBool()) {
+            arguments = {"-w", "media.aaudio"};
+        } else {
+            arguments = {"-l"};
+        }
+    } else {
+        while (mFDP->remaining_bytes() > 0) {
+            size_t sizestr = mFDP->ConsumeIntegralInRange<size_t>(1, mFDP->remaining_bytes());
+            string argument = mFDP->ConsumeBytesAsString(sizestr);
+            arguments.emplace_back(argument);
+        }
+    }
+    vector<string_view> argSV;
+    for (auto& argument : arguments) {
+        argSV.emplace_back(argument.c_str());
+    }
+    int32_t in = open("/dev/null", O_RDWR | O_CREAT);
+    int32_t out = open("/dev/null", O_RDWR | O_CREAT);
+    int32_t err = open("/dev/null", O_RDWR | O_CREAT);
+    TestTextOutput output;
+    TestTextOutput error;
+    RunMode runMode = mFDP->ConsumeBool() ? RunMode::kStandalone : RunMode::kLibrary;
+    cmdMain(argSV, output, error, in, out, err, runMode);
+    delete mFDP;
+    close(in);
+    close(out);
+    close(err);
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    CmdFuzzer cmdFuzzer;
+    cmdFuzzer.process(data, size);
+    return 0;
+}