create error handling logic

Author: Sichao25

src/pcms/assert.cpp

@@ -4,6 +4,50 @@
 #include <cstdlib>
 namespace pcms
 {
+
+namespace
+{
+error_mode current_mode = error_mode::throw_exception;
+}
+
+void set_error_mode(error_mode mode)
+{
+  current_mode = mode;
+}
+
+void handle_error(const exception& e)
+{
+  switch (current_mode) {
+    case error_mode::throw_exception: throw e;
+
+    case error_mode::abort: std::abort();
+
+    case error_mode::return_code:
+    default: break;
+  }
+}
+
+void handle_mpi_error(const pcms::exception& e)
+{
+  int local_fatal = (e.level() == pcms::error_level::fatal);
+  int global_fatal = 0;
+
+  MPI_Allreduce(&local_fatal, &global_fatal, 1, MPI_INT, MPI_MAX,
+                MPI_COMM_WORLD);
+
+  switch (current_mode) {
+    case pcms::error_mode::throw_exception: throw e;
+
+    case pcms::error_mode::abort:
+      if (global_fatal)
+        MPI_Abort(MPI_COMM_WORLD, e.code());
+      break;
+
+    case pcms::error_mode::return_code:
+    default: break;
+  }
+}
+
 void Pcms_Assert_Fail(const char* msg)
 {
   printError("%s", msg);

src/pcms/assert.h

@@ -1,6 +1,9 @@
 #ifndef PCMS_COUPLING_ASSERT_H
 #define PCMS_COUPLING_ASSERT_H
 #include <cassert>
+#include <exception>
+#include <string>
+#include <sstream>
 #include <mpi.h>
 
 // https://stackoverflow.com/questions/16683146/can-macros-be-overloaded-by-number-of-arguments
@@ -44,6 +47,51 @@
 
 namespace pcms
 {
+enum class error_level
+{
+  recoverable,   // safe to continue
+  resource_leak, // may cause resource leaks
+  fatal          // undefined or broken state
+};
+
+enum class error_mode
+{
+  return_code,
+  throw_exception,
+  abort
+};
+
+class exception : public std::exception
+{
+public:
+  exception(std::string message, int error_code = 0,
+            error_level level = error_level::fatal, std::string specific = {})
+    : error_code_(error_code), level_(level)
+  {
+    std::ostringstream oss;
+    oss << message;
+    if (!specific.empty())
+      oss << " | Details: " << specific;
+    if (error_code_ != 0)
+      oss << " | Error code: " << error_code_;
+    error_message_ = oss.str();
+  }
+
+  const char* what() const noexcept override { return error_message_.c_str(); }
+
+  int code() const noexcept { return error_code_; }
+  error_level level() const noexcept { return level_; }
+
+private:
+  std::string error_message_;
+  int error_code_;
+  error_level level_;
+};
+
+void set_error_mode(error_mode mode);
+void handle_error(const exception& e);
+void handle_mpi_error(const exception& e);
+
 // from scorec/core/pcu_fail.h
 void Pcms_Assert_Fail(const char* msg) __attribute__((noreturn));
 } // namespace pcms

test/CMakeLists.txt

@@ -382,6 +382,7 @@ if(Catch2_FOUND)
     list(
       APPEND
       PCMS_UNIT_TEST_SOURCES
+      test_error_handling.cpp
       test_field_transfer.cpp
       test_uniform_grid.cpp
       test_omega_h_copy.cpp

test/test_error_handling.cpp

@@ -0,0 +1,20 @@
+#include <catch2/catch_test_macros.hpp>
+#include "pcms/assert.h"
+#include "pcms/print.h"
+#include <iostream>
+
+int raise_error(int code)
+{
+  if (code) {
+    pcms::handle_error(pcms::exception("Mesh validation failed", 1,
+                                       pcms::error_level::recoverable));
+
+    return 1;
+  }
+  return 0;
+}
+
+TEST_CASE("pcms error handling test")
+{
+  REQUIRE_THROWS_AS(raise_error(1), pcms::exception);
+}