cmUVProcessChain: Add cmUVProcessChain

This class is ultimately intended as a replacement for cmsys::Process.
It spawns a series of processes using libuv, piping the output of each
command into the next.

Note: input support has not yet been implemented because write
support has not yet been implemented on cmUVStreambuf.

3 files changed, 411 insertions, 0 deletions

diff --git a/Tests/CMakeLib/CMakeLists.txt b/Tests/CMakeLib/CMakeLists.txt
index e04bba2..a25f25a 100644
--- a/Tests/CMakeLib/CMakeLists.txt
+++ b/Tests/CMakeLib/CMakeLists.txt
@@ -15,11 +15,15 @@ set(CMakeLib_TESTS
   testXMLParser.cxx
   testXMLSafe.cxx
   testFindPackageCommand.cxx
+  testUVProcessChain.cxx
   testUVRAII.cxx
   testUVStreambuf.cxx
   )
 
+add_executable(testUVProcessChainHelper testUVProcessChainHelper.cxx)
+
 set(testRST_ARGS ${CMAKE_CURRENT_SOURCE_DIR})
+set(testUVProcessChain_ARGS $<TARGET_FILE:testUVProcessChainHelper>)
 set(testUVStreambuf_ARGS $<TARGET_FILE:cmake>)
 
 if(WIN32)
diff --git a/Tests/CMakeLib/testUVProcessChain.cxx b/Tests/CMakeLib/testUVProcessChain.cxx
new file mode 100644
index 0000000..72ae602
--- /dev/null
+++ b/Tests/CMakeLib/testUVProcessChain.cxx
@@ -0,0 +1,335 @@
+#include "cmUVProcessChain.h"
+
+#include "cmAlgorithms.h"
+#include "cmGetPipes.h"
+#include "cmUVHandlePtr.h"
+#include "cmUVStreambuf.h"
+
+#include "cm_uv.h"
+
+#include <algorithm>
+#include <functional>
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+
+#include <csignal>
+
+struct ExpectedStatus
+{
+  bool Finished;
+  bool MatchExitStatus;
+  bool MatchTermSignal;
+  cmUVProcessChain::Status Status;
+};
+
+static const std::vector<ExpectedStatus> status1 = {
+  { false, false, false, { 0, 0 } },
+  { false, false, false, { 0, 0 } },
+  { false, false, false, { 0, 0 } },
+};
+
+static const std::vector<ExpectedStatus> status2 = {
+  { true, true, true, { 0, 0 } },
+  { false, false, false, { 0, 0 } },
+  { false, false, false, { 0, 0 } },
+};
+
+static const std::vector<ExpectedStatus> status3 = {
+  { true, true, true, { 0, 0 } },
+  { true, true, true, { 1, 0 } },
+#ifdef _WIN32
+  { true, true, true, { 2, 0 } },
+#else
+  { true, false, true, { 0, SIGABRT } },
+#endif
+};
+
+bool operator==(const cmUVProcessChain::Status* actual,
+                const ExpectedStatus& expected)
+{
+  if (!expected.Finished) {
+    return !actual;
+  } else if (!actual) {
+    return false;
+  }
+  if (expected.MatchExitStatus &&
+      expected.Status.ExitStatus != actual->ExitStatus) {
+    return false;
+  }
+  if (expected.MatchTermSignal &&
+      expected.Status.TermSignal != actual->TermSignal) {
+    return false;
+  }
+  return true;
+}
+
+bool resultsMatch(const std::vector<const cmUVProcessChain::Status*>& actual,
+                  const std::vector<ExpectedStatus>& expected)
+{
+  return actual.size() == expected.size() &&
+    std::equal(actual.begin(), actual.end(), expected.begin());
+}
+
+std::string getInput(std::istream& input)
+{
+  char buffer[1024];
+  std::ostringstream str;
+  do {
+    input.read(buffer, 1024);
+    str.write(buffer, input.gcount());
+  } while (input.gcount() > 0);
+  return str.str();
+}
+
+template <typename T>
+std::function<std::ostream&(std::ostream&)> printExpected(bool match,
+                                                          const T& value)
+{
+  return [match, value](std::ostream& stream) -> std::ostream& {
+    if (match) {
+      stream << value;
+    } else {
+      stream << "*";
+    }
+    return stream;
+  };
+}
+
+std::ostream& operator<<(
+  std::ostream& stream,
+  const std::function<std::ostream&(std::ostream&)>& func)
+{
+  return func(stream);
+}
+
+void printResults(const std::vector<const cmUVProcessChain::Status*>& actual,
+                  const std::vector<ExpectedStatus>& expected)
+{
+  std::cout << "Expected: " << std::endl;
+  for (auto const& e : expected) {
+    if (e.Finished) {
+      std::cout << "  ExitStatus: "
+                << printExpected(e.MatchExitStatus, e.Status.ExitStatus)
+                << ", TermSignal: "
+                << printExpected(e.MatchTermSignal, e.Status.TermSignal)
+                << std::endl;
+    } else {
+      std::cout << "  null" << std::endl;
+    }
+  }
+  std::cout << "Actual:" << std::endl;
+  for (auto const& a : actual) {
+    if (a) {
+      std::cout << "  ExitStatus: " << a->ExitStatus
+                << ", TermSignal: " << a->TermSignal << std::endl;
+    } else {
+      std::cout << "  null" << std::endl;
+    }
+  }
+}
+
+bool checkExecution(cmUVProcessChainBuilder& builder,
+                    std::unique_ptr<cmUVProcessChain>& chain)
+{
+  std::vector<const cmUVProcessChain::Status*> status;
+
+  chain = cm::make_unique<cmUVProcessChain>(builder.Start());
+  if (!chain->Valid()) {
+    std::cout << "Valid() returned false, should be true" << std::endl;
+    return false;
+  }
+  status = chain->GetStatus();
+  if (!resultsMatch(status, status1)) {
+    std::cout << "GetStatus() did not produce expected output" << std::endl;
+    printResults(status, status1);
+    return false;
+  }
+
+  if (chain->Wait(6000)) {
+    std::cout << "Wait() returned true, should be false" << std::endl;
+    return false;
+  }
+  status = chain->GetStatus();
+  if (!resultsMatch(status, status2)) {
+    std::cout << "GetStatus() did not produce expected output" << std::endl;
+    printResults(status, status2);
+    return false;
+  }
+
+  if (!chain->Wait()) {
+    std::cout << "Wait() returned false, should be true" << std::endl;
+    return false;
+  }
+  status = chain->GetStatus();
+  if (!resultsMatch(status, status3)) {
+    std::cout << "GetStatus() did not produce expected output" << std::endl;
+    printResults(status, status3);
+    return false;
+  }
+
+  return true;
+}
+
+bool checkOutput(std::istream& outputStream, std::istream& errorStream)
+{
+  std::string output = getInput(outputStream);
+  if (output != "HELO WRD!") {
+    std::cout << "Output was \"" << output << "\", expected \"HELO WRD!\""
+              << std::endl;
+    return false;
+  }
+
+  std::string error = getInput(errorStream);
+  if (error.length() != 3 || error.find('1') == std::string::npos ||
+      error.find('2') == std::string::npos ||
+      error.find('3') == std::string::npos) {
+    std::cout << "Error was \"" << error << "\", expected \"123\""
+              << std::endl;
+    return false;
+  }
+
+  return true;
+}
+
+bool testUVProcessChainBuiltin(const char* helperCommand)
+{
+  cmUVProcessChainBuilder builder;
+  std::unique_ptr<cmUVProcessChain> chain;
+  builder.AddCommand({ helperCommand, "echo" })
+    .AddCommand({ helperCommand, "capitalize" })
+    .AddCommand({ helperCommand, "dedup" })
+    .SetBuiltinStream(cmUVProcessChainBuilder::Stream_OUTPUT)
+    .SetBuiltinStream(cmUVProcessChainBuilder::Stream_ERROR);
+
+  if (!checkExecution(builder, chain)) {
+    return false;
+  }
+
+  if (!chain->OutputStream()) {
+    std::cout << "OutputStream() was null, expecting not null" << std::endl;
+    return false;
+  }
+  if (!chain->ErrorStream()) {
+    std::cout << "ErrorStream() was null, expecting not null" << std::endl;
+    return false;
+  }
+
+  if (!checkOutput(*chain->OutputStream(), *chain->ErrorStream())) {
+    return false;
+  }
+
+  return true;
+}
+
+bool testUVProcessChainExternal(const char* helperCommand)
+{
+  cmUVProcessChainBuilder builder;
+  std::unique_ptr<cmUVProcessChain> chain;
+  int outputPipe[2], errorPipe[2];
+  cm::uv_pipe_ptr outputInPipe, outputOutPipe, errorInPipe, errorOutPipe;
+
+  if (cmGetPipes(outputPipe) < 0) {
+    std::cout << "Error creating pipes" << std::endl;
+    return false;
+  }
+  if (cmGetPipes(errorPipe) < 0) {
+    std::cout << "Error creating pipes" << std::endl;
+    return false;
+  }
+
+  builder.AddCommand({ helperCommand, "echo" })
+    .AddCommand({ helperCommand, "capitalize" })
+    .AddCommand({ helperCommand, "dedup" })
+    .SetExternalStream(cmUVProcessChainBuilder::Stream_OUTPUT, outputPipe[1])
+    .SetExternalStream(cmUVProcessChainBuilder::Stream_ERROR, errorPipe[1]);
+
+  if (!checkExecution(builder, chain)) {
+    return false;
+  }
+
+  if (chain->OutputStream()) {
+    std::cout << "OutputStream() was not null, expecting null" << std::endl;
+    return false;
+  }
+  if (chain->ErrorStream()) {
+    std::cout << "ErrorStream() was not null, expecting null" << std::endl;
+    return false;
+  }
+
+  outputOutPipe.init(chain->GetLoop(), 0);
+  uv_pipe_open(outputOutPipe, outputPipe[1]);
+  outputOutPipe.reset();
+
+  errorOutPipe.init(chain->GetLoop(), 0);
+  uv_pipe_open(errorOutPipe, errorPipe[1]);
+  errorOutPipe.reset();
+
+  outputInPipe.init(chain->GetLoop(), 0);
+  uv_pipe_open(outputInPipe, outputPipe[0]);
+  cmUVStreambuf outputBuf;
+  outputBuf.open(outputInPipe);
+  std::istream outputStream(&outputBuf);
+
+  errorInPipe.init(chain->GetLoop(), 0);
+  uv_pipe_open(errorInPipe, errorPipe[0]);
+  cmUVStreambuf errorBuf;
+  errorBuf.open(errorInPipe);
+  std::istream errorStream(&errorBuf);
+
+  if (!checkOutput(outputStream, errorStream)) {
+    return false;
+  }
+
+  return true;
+}
+
+bool testUVProcessChainNone(const char* helperCommand)
+{
+  cmUVProcessChainBuilder builder;
+  std::unique_ptr<cmUVProcessChain> chain;
+  builder.AddCommand({ helperCommand, "echo" })
+    .AddCommand({ helperCommand, "capitalize" })
+    .AddCommand({ helperCommand, "dedup" });
+
+  if (!checkExecution(builder, chain)) {
+    return false;
+  }
+
+  if (chain->OutputStream()) {
+    std::cout << "OutputStream() was not null, expecting null" << std::endl;
+    return false;
+  }
+  if (chain->ErrorStream()) {
+    std::cout << "ErrorStream() was not null, expecting null" << std::endl;
+    return false;
+  }
+
+  return true;
+}
+
+int testUVProcessChain(int argc, char** const argv)
+{
+  if (argc < 2) {
+    std::cout << "Invalid arguments.\n";
+    return -1;
+  }
+
+  if (!testUVProcessChainBuiltin(argv[1])) {
+    std::cout << "While executing testUVProcessChainBuiltin().\n";
+    return -1;
+  }
+
+  if (!testUVProcessChainExternal(argv[1])) {
+    std::cout << "While executing testUVProcessChainExternal().\n";
+    return -1;
+  }
+
+  if (!testUVProcessChainNone(argv[1])) {
+    std::cout << "While executing testUVProcessChainNone().\n";
+    return -1;
+  }
+
+  return 0;
+}
diff --git a/Tests/CMakeLib/testUVProcessChainHelper.cxx b/Tests/CMakeLib/testUVProcessChainHelper.cxx
new file mode 100644
index 0000000..263665d
--- /dev/null
+++ b/Tests/CMakeLib/testUVProcessChainHelper.cxx
@@ -0,0 +1,72 @@
+#include <chrono>
+#include <iostream>
+#include <set>
+#include <sstream>
+#include <string>
+#include <thread>
+
+#include <cctype>
+#include <cstdlib>
+
+std::string getStdin()
+{
+  char buffer[1024];
+  std::ostringstream str;
+  do {
+    std::cin.read(buffer, 1024);
+    str.write(buffer, std::cin.gcount());
+  } while (std::cin.gcount() > 0);
+  return str.str();
+}
+
+int main(int argc, char** argv)
+{
+  if (argc < 2) {
+    return -1;
+  }
+
+  std::string command = argv[1];
+  if (command == "echo") {
+    std::this_thread::sleep_for(std::chrono::milliseconds(3000));
+    std::cout << "HELLO world!" << std::flush;
+    std::cerr << "1" << std::flush;
+    return 0;
+  }
+  if (command == "capitalize") {
+    std::this_thread::sleep_for(std::chrono::milliseconds(9000));
+    std::string input = getStdin();
+    for (auto& c : input) {
+      c = static_cast<char>(std::toupper(c));
+    }
+    std::cout << input << std::flush;
+    std::cerr << "2" << std::flush;
+    return 1;
+  }
+  if (command == "dedup") {
+    // Use a nested scope to free all resources before aborting below.
+    {
+      std::string input = getStdin();
+      std::set<char> seen;
+      std::string output;
+      for (auto c : input) {
+        if (!seen.count(c)) {
+          seen.insert(c);
+          output += c;
+        }
+      }
+      std::cout << output << std::flush;
+      std::cerr << "3" << std::flush;
+    }
+
+    // On Windows, the exit code of abort() is different between debug and
+    // release builds, and does not yield a term_signal in libuv in either
+    // case. For the sake of simplicity, we just return another non-zero code.
+#ifdef _WIN32
+    return 2;
+#else
+    std::abort();
+#endif
+  }
+
+  return -1;
+}