testing: move atf-pytest-wrapper to /usr/libexec

Move pytest wrapper to the collection of the other atf wrappers
 in libexec. It solves the problem of combining bits & pieces from
 bsd.test.mk and bgs.prog.mk to address "test binary, but not the
 suite binary".

Reviewed by:	kp
Differential Revision: https://reviews.freebsd.org/D35604
MFC after:	2 weeks

3 files changed, 203 insertions, 1 deletions

diff --git a/libexec/atf/Makefile b/libexec/atf/Makefile
index db7554d9ddaa..77819aeff697 100644
--- a/libexec/atf/Makefile
+++ b/libexec/atf/Makefile
@@ -25,6 +25,6 @@
 #
 # $FreeBSD$
 
-SUBDIR=	atf-check atf-sh tests
+SUBDIR=	atf-check atf-pytest-wrapper atf-sh tests
 
 .include <bsd.subdir.mk>
diff --git a/libexec/atf/atf-pytest-wrapper/Makefile b/libexec/atf/atf-pytest-wrapper/Makefile
new file mode 100644
index 000000000000..e4dc0f8a5fd1
--- /dev/null
+++ b/libexec/atf/atf-pytest-wrapper/Makefile
@@ -0,0 +1,10 @@
+.include <src.opts.mk>
+.include <bsd.init.mk>
+
+PACKAGE=	tests
+PROG_CXX=	atf_pytest_wrapper
+SRCS=		atf_pytest_wrapper.cpp
+CXXSTD=		c++17
+MAN=
+
+.include <bsd.prog.mk>
diff --git a/libexec/atf/atf-pytest-wrapper/atf_pytest_wrapper.cpp b/libexec/atf/atf-pytest-wrapper/atf_pytest_wrapper.cpp
new file mode 100644
index 000000000000..11fd3c47d507
--- /dev/null
+++ b/libexec/atf/atf-pytest-wrapper/atf_pytest_wrapper.cpp
@@ -0,0 +1,192 @@
+#include <format>
+#include <iostream>
+#include <string>
+#include <vector>
+#include <stdlib.h>
+#include <unistd.h>
+
+class Handler {
+  private:
+    const std::string kPytestName = "pytest";
+    const std::string kCleanupSuffix = ":cleanup";
+    const std::string kPythonPathEnv = "PYTHONPATH";
+  public:
+    // Test listing requested
+    bool flag_list = false;
+    // Output debug data (will break listing)
+    bool flag_debug = false;
+    // Cleanup for the test requested
+    bool flag_cleanup = false;
+    // Test source directory (provided by ATF)
+    std::string src_dir;
+    // Path to write test status to (provided by ATF)
+    std::string dst_file;
+    // Path to add to PYTHONPATH (provided by the schebang args)
+    std::string python_path;
+    // Path to the script (provided by the schebang wrapper)
+    std::string script_path;
+    // Name of the test to run (provided by ATF)
+    std::string test_name;
+    // kv pairs (provided by ATF)
+    std::vector<std::string> kv_list;
+    // our binary name
+    std::string binary_name;
+
+    static std::vector<std::string> ToVector(int argc, char **argv) {
+      std::vector<std::string> ret;
+
+      for (int i = 0; i < argc; i++) {
+        ret.emplace_back(std::string(argv[i]));
+      }
+      return ret;
+    }
+
+    static void PrintVector(std::string prefix, const std::vector<std::string> &vec) {
+      std::cerr << prefix << ": ";
+      for (auto &val: vec) {
+        std::cerr << "'" << val << "' ";
+      }
+      std::cerr << std::endl;
+    }
+
+    void Usage(std::string msg, bool exit_with_error) {
+      std::cerr << binary_name << ": ERROR: " << msg << "." << std::endl;
+      std::cerr << binary_name << ": See atf-test-program(1) for usage details." << std::endl;
+      exit(exit_with_error != 0);
+    }
+
+    // Parse args received from the OS. There can be multiple valid options:
+    // * with schebang args (#!/binary -P/path):
+    // atf_wrap '-P /path' /path/to/script -l
+    // * without schebang args
+    // atf_wrap /path/to/script -l
+    // Running test:
+    // atf_wrap '-P /path' /path/to/script -r /path1 -s /path2 -vk1=v1 testname 
+    void Parse(int argc, char **argv) {
+      if (flag_debug) {
+        PrintVector("IN", ToVector(argc, argv));
+      }
+      // getopt() skips the first argument (as it is typically binary name)
+      // it is possible to have either '-P\s*/path' followed by the script name
+      // or just the script name. Parse kernel-provided arg manually and adjust
+      // array to make getopt work
+
+      binary_name = std::string(argv[0]);
+      argc--; argv++;
+      // parse -P\s*path from the kernel.
+      if (argc > 0 && !strncmp(argv[0], "-P", 2)) {
+        char *path = &argv[0][2];
+        while (*path == ' ')
+          path++;
+        python_path = std::string(path);
+        argc--; argv++;
+      }
+
+      // The next argument is a script name. Copy and keep argc/argv the same
+      // Show usage for empty args
+      if (argc == 0) {
+          Usage("Must provide a test case name", true);
+      }
+      script_path = std::string(argv[0]);
+
+      int c;
+      while ((c = getopt(argc, argv, "lr:s:v:")) != -1) {
+        switch (c) {
+        case 'l':
+          flag_list = true;
+          break;
+        case 's':
+          src_dir = std::string(optarg);
+          break;
+        case 'r':
+          dst_file = std::string(optarg);
+          break;
+        case 'v':
+          kv_list.emplace_back(std::string(optarg));
+          break;
+        default:
+          Usage("Unknown option -" + std::string(1, static_cast<char>(c)), true);
+        }
+      }
+      argc -= optind;
+      argv += optind;
+
+      if (flag_list) {
+        return;
+      }
+      // There should be just one argument with the test name
+      if (argc != 1) {
+        Usage("Must provide a test case name", true);
+      }
+      test_name = std::string(argv[0]);
+      if (test_name.size() > kCleanupSuffix.size() &&
+          std::equal(kCleanupSuffix.rbegin(), kCleanupSuffix.rend(), test_name.rbegin())) {
+        test_name = test_name.substr(0, test_name.size() - kCleanupSuffix.size());
+        flag_cleanup = true;
+      }
+    }
+
+    std::vector<std::string> BuildArgs() {
+      std::vector<std::string> args = {"pytest", "-p", "no:cacheprovider", "-s", "--atf"};
+
+      if (flag_list) {
+        args.push_back("--co");
+        args.push_back(script_path);
+        return args;
+      }
+      if (flag_cleanup) {
+        args.push_back("--atf-cleanup");
+      }
+      if (!src_dir.empty()) {
+        args.push_back("--atf-source-dir");
+        args.push_back(src_dir);
+      }
+      if (!dst_file.empty()) {
+        args.push_back("--atf-file");
+        args.push_back(dst_file);
+      }
+      for (auto &pair: kv_list) {
+        args.push_back("--atf-var");
+        args.push_back(pair);
+      }
+      // Create nodeid from the test path &name
+      args.push_back(script_path + "::" + test_name);
+      return args;
+    }
+
+    void SetEnv() {
+      if (!python_path.empty()) {
+        char *env_path = getenv(kPythonPathEnv.c_str());
+        if (env_path != nullptr) {
+          python_path = python_path + ":" + std::string(env_path);
+        }
+        setenv(kPythonPathEnv.c_str(), python_path.c_str(), 1);
+      }
+    }
+
+    int Run(std::string binary, std::vector<std::string> args) {
+      if (flag_debug) {
+        PrintVector("OUT", args);
+      }
+      // allocate array with final NULL
+      char **arr = new char*[args.size() + 1]();
+      for (unsigned long i = 0; i < args.size(); i++) {
+	// work around 'char *const *'
+        arr[i] = strdup(args[i].c_str());
+      }
+      return (execvp(binary.c_str(), arr) != 0);
+    }
+
+    int Process() {
+      SetEnv();
+      return Run(kPytestName, BuildArgs());
+    }
+};
+
+
+int main(int argc, char **argv) {
+  Handler handler;
+
+  handler.Parse(argc, argv);
+  return handler.Process();
+}