Env var

src/CMakeLists.txt

@@ -1,6 +1,7 @@
 target_sources(oomph_common PRIVATE utils.cpp)
 target_sources(oomph_common PRIVATE thread_id.cpp)
 target_sources(oomph_common PRIVATE rank_topology.cpp)
+target_sources(oomph_common PRIVATE env_vars.cpp)
 
 if (OOMPH_WITH_MPI)
     add_subdirectory(mpi)

src/env_vars.cpp

@@ -0,0 +1,71 @@
+/*
+ * ghex-org
+ *
+ * Copyright (c) 2014-2022, ETH Zurich
+ * All rights reserved.
+ *
+ * Please, refer to the LICENSE file in the root directory.
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+extern char** environ;
+
+#include <iostream>
+#include <algorithm>
+#include "./env_vars.hpp"
+
+namespace oomph
+{
+
+env_vars::env_vars()
+{
+    char** s = environ;
+    for (; *s; s++)
+    {
+        std::string_view v(*s);
+        auto const       pos = v.find('=');
+        if (pos == std::string_view::npos) m_vars[v] = std::string_view();
+        else
+            m_vars[v.substr(0, pos)] = v.substr(pos + 1);
+    }
+}
+
+void
+env_vars::print() const noexcept
+{
+    for (auto const& p : m_vars) std::cout << p.first << "=" << p.second << "\n";
+    std::cout << std::endl;
+}
+
+std::vector<std::pair<std::string_view, std::string_view>>
+env_vars::key_contains(char const* k) const
+{
+    std::vector<std::pair<std::string_view, std::string_view>> res;
+
+    std::string_view v(k);
+    auto pred = [v](auto const& p) { return p.first.find(v) != std::string_view::npos; };
+    auto it = m_vars.begin();
+    while (true)
+    {
+        it = std::find_if(it, m_vars.end(), pred);
+        if (it == m_vars.end()) break;
+        else
+        {
+            res.push_back(*it);
+            ++it;
+            if (it == m_vars.end()) break;
+        }
+    }
+    return res;
+}
+
+std::optional<std::string_view>
+env_vars::find(char const* k) const noexcept
+{
+    auto it = m_vars.find(std::string_view(k));
+    if (it == m_vars.end()) return {};
+    else
+        return it->second;
+}
+
+} // namespace oomph

src/env_vars.hpp

@@ -0,0 +1,37 @@
+/*
+ * ghex-org
+ *
+ * Copyright (c) 2014-2022, ETH Zurich
+ * All rights reserved.
+ *
+ * Please, refer to the LICENSE file in the root directory.
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#pragma once
+
+#include <map>
+#include <string_view>
+#include <optional>
+#include <vector>
+
+namespace oomph
+{
+
+class env_vars
+{
+  private:
+    using map_type = std::map<std::string_view, std::string_view>;
+
+    map_type m_vars;
+
+  public:
+    env_vars();
+
+    void print() const noexcept;
+
+    std::vector<std::pair<std::string_view, std::string_view>> key_contains(char const* k) const;
+
+    std::optional<std::string_view> find(char const* k) const noexcept;
+};
+
+} // namespace oomph

test/CMakeLists.txt

@@ -6,6 +6,9 @@ add_subdirectory(mpi_runner)
 # compile tests
 # ---------------------------------------------------------------------
 
+# list of serial tests to be executed
+set(serial_tests test_env_vars)
+
 # list of tests to be executed
 set(parallel_tests test_context test_send_recv test_send_multi test_cancel test_locality)
 if (OOMPH_ENABLE_BARRIER)
@@ -23,14 +26,30 @@ endfunction()
 
 # compile an object library for each test
 # tests will be compiled only once and then linked against all enabled oomph backends
-foreach(t ${parallel_tests})
+list(APPEND all_tests ${serial_tests} ${parallel_tests})
+list(REMOVE_DUPLICATES all_tests)
+foreach(t ${all_tests})
     compile_test(${t})
 endforeach()
 
 # ---------------------------------------------------------------------
 # link and register tests
 # ---------------------------------------------------------------------
 
+function(reg_serial_test t)
+    add_executable(${t} $<TARGET_OBJECTS:${t}_obj>)
+    oomph_target_compile_options(${t})
+    target_link_libraries(${t} PRIVATE gtest_main)
+    target_link_libraries(${t} PRIVATE oomph_common)
+    add_test(
+        NAME ${t}
+        COMMAND $<TARGET_FILE:${t}>)
+endfunction()
+
+foreach(t ${serial_tests})
+    reg_serial_test(${t})
+endforeach()
+
 # creates an executable by linking to object file and to selected oomph backend
 function(reg_parallel_test t_ lib n)
     set(t ${t_}_${lib})

test/test_env_vars.cpp

@@ -0,0 +1,44 @@
+/*
+ * ghex-org
+ *
+ * Copyright (c) 2014-2022, ETH Zurich
+ * All rights reserved.
+ *
+ * Please, refer to the LICENSE file in the root directory.
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+#include <gtest/gtest.h>
+#include "../src/env_vars.hpp"
+
+TEST(env_vars, print)
+{
+    using namespace oomph;
+
+    env_vars ev;
+    ev.print();
+
+    std::cout << "==========" << std::endl;
+    for (const auto& p : ev.key_contains("HOM"))
+    {
+        std::cout << p.first << " = " << p.second << std::endl;
+    }
+    std::cout << "==========" << std::endl;
+    for (const auto& p : ev.key_contains("hom"))
+    {
+        std::cout << p.first << " = " << p.second << std::endl;
+    }
+    std::cout << "==========" << std::endl;
+    for (const auto& p : ev.key_contains("H"))
+    {
+        std::cout << p.first << " = " << p.second << std::endl;
+    }
+
+    std::cout << "==========" << std::endl;
+    if (auto v = ev.find("HOME"))
+    {
+        std::cout << *v << std::endl;
+    }
+}
+
+