Optimize configuration loading: cache JSON

- Moved environment variable parsing to a dedicated loadConfig() function, called only once during initialization of the global g_jsonConfig.
- Updated GetJson() to return the cached JSON object, preventing repetitive parsing of environment variables on each access.
- Improved performance and simplified configuration data access.

Replace <stdio.h> with <cstdlib> and <cstdio>

- Updated include directives to use modern C++ headers.
- The new headers place standard library functions in the std namespace, enhancing compatibility and type safety as recommended by modern C++ standards.
This commit is contained in:
Serhii Maltsev 2025-02-28 13:35:11 +01:00
parent cc852b424a
commit f42604c527

View file

@ -4,7 +4,6 @@ Written by daijro.
*/
#pragma once
#include "json.hpp"
#include <memory>
#include <string>
@ -12,10 +11,12 @@ Written by daijro.
#include <optional>
#include <codecvt>
#include "mozilla/glue/Debug.h"
#include <stdlib.h>
#include <stdio.h>
#include <cstdlib>
#include <cstdio>
#include <variant>
#include <cstddef>
#include <vector>
#include <algorithm>
#ifdef _WIN32
# include <windows.h>
@ -23,182 +24,188 @@ Written by daijro.
namespace MaskConfig {
// Function to get the value of an environment variable as a UTF-8 string.
inline std::optional<std::string> get_env_utf8(const std::string& name) {
#ifdef _WIN32
std::wstring wName(name.begin(), name.end());
DWORD size = GetEnvironmentVariableW(wName.c_str(), nullptr, 0);
if (size == 0) return std::nullopt; // Environment variable not found
std::wstring wName(name.begin(), name.end());
DWORD size = GetEnvironmentVariableW(wName.c_str(), nullptr, 0);
if (size == 0) return std::nullopt; // Environment variable not found
std::vector<wchar_t> buffer(size);
GetEnvironmentVariableW(wName.c_str(), buffer.data(), size);
std::wstring wValue(buffer.data());
std::vector<wchar_t> buffer(size);
GetEnvironmentVariableW(wName.c_str(), buffer.data(), size);
std::wstring wValue(buffer.data());
// Convert UTF-16 to UTF-8
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
return converter.to_bytes(wValue);
// Convert UTF-16 to UTF-8
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
return converter.to_bytes(wValue);
#else
const char* value = getenv(name.c_str());
if (!value) return std::nullopt;
return std::string(value);
const char* value = std::getenv(name.c_str());
if (!value) return std::nullopt;
return std::string(value);
#endif
}
inline const nlohmann::json& GetJson() {
static const nlohmann::json jsonConfig = []() {
// Helper function to load and parse configuration from environment variables.
namespace {
nlohmann::json loadConfig() {
std::string jsonString;
int index = 1;
// Read environment variables CAMOU_CONFIG_1, CAMOU_CONFIG_2, ...
while (true) {
std::string envName = "CAMOU_CONFIG_" + std::to_string(index);
auto partialConfig = get_env_utf8(envName);
if (!partialConfig) break;
jsonString += *partialConfig;
index++;
std::string envName = "CAMOU_CONFIG_" + std::to_string(index);
auto partialConfig = get_env_utf8(envName);
if (!partialConfig)
break;
jsonString += *partialConfig;
index++;
}
// If the concatenated string is empty, try reading the original CAMOU_CONFIG variable.
if (jsonString.empty()) {
// Check for the original CAMOU_CONFIG as fallback
auto originalConfig = get_env_utf8("CAMOU_CONFIG");
if (originalConfig) jsonString = *originalConfig;
auto originalConfig = get_env_utf8("CAMOU_CONFIG");
if (originalConfig)
jsonString = *originalConfig;
}
if (jsonString.empty()) return nlohmann::json{};
// If no configuration is provided, return an empty JSON.
if (jsonString.empty()) {
return nlohmann::json{};
}
// Validate
// Validate JSON correctness.
if (!nlohmann::json::accept(jsonString)) {
printf_stderr("ERROR: Invalid JSON passed to CAMOU_CONFIG!\n");
return nlohmann::json{};
printf_stderr("ERROR: Invalid JSON passed to CAMOU_CONFIG!\n");
return nlohmann::json{};
}
nlohmann::json result = nlohmann::json::parse(jsonString);
return result;
}();
return jsonConfig;
return nlohmann::json::parse(jsonString);
}
} // namespace
// Global configuration cache, initialized only once.
static const nlohmann::json g_jsonConfig = loadConfig();
// Function returns a reference to the already parsed JSON.
inline const nlohmann::json& GetJson() {
return g_jsonConfig;
}
inline bool HasKey(const std::string& key, nlohmann::json& data) {
// printf_stderr("Property: %s\n", key.c_str());
// printf_stderr("WARNING: Key not found: %s\n", key.c_str());
return data.contains(key);
inline bool HasKey(const std::string& key, const nlohmann::json& data) {
return data.contains(key);
}
inline std::optional<std::string> GetString(const std::string& key) {
// printf_stderr("GetString: %s\n", key.c_str());
auto data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
return std::make_optional(data[key].get<std::string>());
const auto& data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
return data[key].get<std::string>();
}
inline std::vector<std::string> GetStringList(const std::string& key) {
std::vector<std::string> result;
auto data = GetJson();
if (!HasKey(key, data)) return {};
// Build vector
for (const auto& item : data[key]) {
result.push_back(item.get<std::string>());
}
return result;
std::vector<std::string> result;
const auto& data = GetJson();
if (!HasKey(key, data)) return {};
for (const auto& item : data[key]) {
result.push_back(item.get<std::string>());
}
return result;
}
inline std::vector<std::string> GetStringListLower(const std::string& key) {
std::vector<std::string> result = GetStringList(key);
for (auto& str : result) {
std::transform(str.begin(), str.end(), str.begin(),
[](unsigned char c) { return std::tolower(c); });
}
return result;
std::vector<std::string> result = GetStringList(key);
for (auto& str : result) {
std::transform(str.begin(), str.end(), str.begin(),
[](unsigned char c) { return std::tolower(c); });
}
return result;
}
template <typename T>
inline std::optional<T> GetUintImpl(const std::string& key) {
auto data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_number_unsigned())
return std::make_optional(data[key].get<T>());
printf_stderr("ERROR: Value for key '%s' is not an unsigned integer\n",
key.c_str());
return std::nullopt;
const auto& data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_number_unsigned())
return data[key].get<T>();
printf_stderr("ERROR: Value for key '%s' is not an unsigned integer\n", key.c_str());
return std::nullopt;
}
inline std::optional<uint64_t> GetUint64(const std::string& key) {
return GetUintImpl<uint64_t>(key);
return GetUintImpl<uint64_t>(key);
}
inline std::optional<uint32_t> GetUint32(const std::string& key) {
return GetUintImpl<uint32_t>(key);
return GetUintImpl<uint32_t>(key);
}
inline std::optional<int32_t> GetInt32(const std::string& key) {
auto data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_number_integer())
return std::make_optional(data[key].get<int32_t>());
printf_stderr("ERROR: Value for key '%s' is not an integer\n", key.c_str());
return std::nullopt;
const auto& data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_number_integer())
return data[key].get<int32_t>();
printf_stderr("ERROR: Value for key '%s' is not an integer\n", key.c_str());
return std::nullopt;
}
inline std::optional<double> GetDouble(const std::string& key) {
auto data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_number_float())
return std::make_optional(data[key].get<double>());
if (data[key].is_number_unsigned() || data[key].is_number_integer())
return std::make_optional(static_cast<double>(data[key].get<int64_t>()));
printf_stderr("ERROR: Value for key '%s' is not a double\n", key.c_str());
return std::nullopt;
const auto& data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_number_float())
return data[key].get<double>();
if (data[key].is_number_unsigned() || data[key].is_number_integer())
return static_cast<double>(data[key].get<int64_t>());
printf_stderr("ERROR: Value for key '%s' is not a double\n", key.c_str());
return std::nullopt;
}
inline std::optional<bool> GetBool(const std::string& key) {
auto data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_boolean()) return std::make_optional(data[key].get<bool>());
printf_stderr("ERROR: Value for key '%s' is not a boolean\n", key.c_str());
return std::nullopt;
const auto& data = GetJson();
if (!HasKey(key, data)) return std::nullopt;
if (data[key].is_boolean()) return data[key].get<bool>();
printf_stderr("ERROR: Value for key '%s' is not a boolean\n", key.c_str());
return std::nullopt;
}
inline bool CheckBool(const std::string& key) {
return GetBool(key).value_or(false);
return GetBool(key).value_or(false);
}
inline std::optional<std::array<uint32_t, 4>> GetRect(
const std::string& left, const std::string& top, const std::string& width,
const std::string& height) {
// Make top and left default to 0
std::array<std::optional<uint32_t>, 4> values = {
GetUint32(left).value_or(0), GetUint32(top).value_or(0), GetUint32(width),
GetUint32(height)};
inline std::optional<std::array<uint32_t, 4>> GetRect(const std::string& left,
const std::string& top,
const std::string& width,
const std::string& height) {
std::array<std::optional<uint32_t>, 4> values = {
GetUint32(left).value_or(0),
GetUint32(top).value_or(0),
GetUint32(width),
GetUint32(height)
};
// If height or width is std::nullopt, return std::nullopt
if (!values[2].has_value() || !values[3].has_value()) {
if (values[2].has_value() ^ values[3].has_value())
printf_stderr(
"Both %s and %s must be provided. Using default "
"behavior.\n",
height.c_str(), width.c_str());
return std::nullopt;
}
if (!values[2].has_value() || !values[3].has_value()) {
if (values[2].has_value() ^ values[3].has_value())
printf_stderr("Both %s and %s must be provided. Using default behavior.\n",
height.c_str(), width.c_str());
return std::nullopt;
}
// Convert std::optional<uint32_t> to uint32_t
std::array<uint32_t, 4> result;
std::transform(values.begin(), values.end(), result.begin(),
[](const auto& value) { return value.value(); });
std::array<uint32_t, 4> result;
std::transform(values.begin(), values.end(), result.begin(),
[](const auto& value) { return value.value(); });
return result;
}
inline std::optional<std::array<int32_t, 4>> GetInt32Rect(
const std::string& left, const std::string& top, const std::string& width,
const std::string& height) {
// Calls GetRect but casts to int32_t
if (auto optValue = GetRect(left, top, width, height)) {
std::array<int32_t, 4> result;
std::transform(optValue->begin(), optValue->end(), result.begin(),
[](const auto& val) { return static_cast<int32_t>(val); });
return result;
}
return std::nullopt;
}
inline std::optional<std::array<int32_t, 4>> GetInt32Rect(const std::string& left,
const std::string& top,
const std::string& width,
const std::string& height) {
if (auto optValue = GetRect(left, top, width, height)) {
std::array<int32_t, 4> result;
std::transform(optValue->begin(), optValue->end(), result.begin(),
[](const auto& val) { return static_cast<int32_t>(val); });
return result;
}
return std::nullopt;
}
// Helpers for WebGL