Initial self-hosting commit

This is the initial version of our tool that is able to
build itself. In can be bootstrapped by

  ./bin/bootstrap.py

Co-authored-by: Oliver Reiche <oliver.reiche@huawei.com>
Co-authored-by: Victor Moreno <victor.moreno1@huawei.com>

1 files changed, 83 insertions, 0 deletions

diff --git a/src/utils/cpp/json.hpp b/src/utils/cpp/json.hpp
new file mode 100644
index 00000000..8945e975
--- /dev/null
+++ b/src/utils/cpp/json.hpp
@@ -0,0 +1,83 @@
+#ifndef INCLUDED_SRC_UTILS_CPP_JSON_HPP
+#define INCLUDED_SRC_UTILS_CPP_JSON_HPP
+
+#include <algorithm>
+#include <optional>
+#include <sstream>
+#include <string>
+
+#include "nlohmann/json.hpp"
+#include "gsl-lite/gsl-lite.hpp"
+
+template <typename ValueT>
+auto ExtractValueAs(
+    nlohmann::json const& j,
+    std::string const& key,
+    std::function<void(std::string const& error)>&& logger =
+        [](std::string const & /*unused*/) -> void {}) noexcept
+    -> std::optional<ValueT> {
+    try {
+        auto it = j.find(key);
+        if (it == j.end()) {
+            logger("key " + key + " cannot be found in JSON object");
+            return std::nullopt;
+        }
+        return it.value().template get<ValueT>();
+    } catch (std::exception& e) {
+        logger(e.what());
+        return std::nullopt;
+    }
+}
+
+namespace detail {
+
+[[nodiscard]] static inline auto IndentListsOnlyUntilDepth(
+    nlohmann::json const& json,
+    std::string const& indent,
+    std::size_t until,
+    std::size_t depth) -> std::string {
+    using iterator = std::ostream_iterator<std::string>;
+    if (json.is_object()) {
+        std::size_t i{};
+        std::ostringstream oss{};
+        oss << '{' << std::endl;
+        for (auto const& [key, value] : json.items()) {
+            std::fill_n(iterator{oss}, depth + 1, indent);
+            oss << nlohmann::json(key).dump() << ": "
+                << IndentListsOnlyUntilDepth(value, indent, until, depth + 1)
+                << (++i == json.size() ? "" : ",") << std::endl;
+        }
+        std::fill_n(iterator{oss}, depth, indent);
+        oss << '}';
+        gsl_EnsuresAudit(nlohmann::json::parse(oss.str()) == json);
+        return oss.str();
+    }
+    if (json.is_array() and depth < until) {
+        std::size_t i{};
+        std::ostringstream oss{};
+        oss << '[' << std::endl;
+        for (auto const& value : json) {
+            std::fill_n(iterator{oss}, depth + 1, indent);
+            oss << IndentListsOnlyUntilDepth(value, indent, until, depth + 1)
+                << (++i == json.size() ? "" : ",") << std::endl;
+        }
+        std::fill_n(iterator{oss}, depth, indent);
+        oss << ']';
+        gsl_EnsuresAudit(nlohmann::json::parse(oss.str()) == json);
+        return oss.str();
+    }
+    return json.dump();
+}
+
+}  // namespace detail
+
+/// \brief Dump json with indent. Indent lists only until specified depth.
+[[nodiscard]] static inline auto IndentListsOnlyUntilDepth(
+    nlohmann::json const& json,
+    std::size_t indent,
+    std::size_t until_depth = 0) -> std::string {
+    return detail::IndentListsOnlyUntilDepth(
+        json, std::string(indent, ' '), until_depth, 0);
+}
+
+#endif  // INCLUDED_SRC_UTILS_CPP_JSON_HPP