utils.h

/*
This file is part of FlashMQ (https://www.flashmq.org)
Copyright (C) 2021-2023 Wiebe Cazemier

FlashMQ is free software: you can redistribute it and/or modify
it under the terms of The Open Software License 3.0 (OSL-3.0).

See LICENSE for license details.
*/

#ifndef UTILS_H
#define UTILS_H

#include <string.h>
#include <errno.h>
#include <string>
#include <list>
#include <limits>
#include <vector>
#include <algorithm>
#include <openssl/evp.h>
#include <memory>
#include <arpa/inet.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/random.h>
#include <stdexcept>

#include "cirbuf.h"
#include "bindaddr.h"
#include "types.h"
#include "flashmq_plugin.h"

#define UNUSED(expr) do { (void)(expr); } while (0)

template<typename T> int check(int rc)
{
    if (rc < 0)
    {
        char *err = strerror(errno);
        std::string msg(err);
        throw T(msg);
    }

    return rc;
}

std::list<std::string> split(const std::string &input, const char sep, size_t max = std::numeric_limits<int>::max(), bool keep_empty_parts = true);
std::vector<std::string> splitToVector(const std::string &input, const char sep, size_t max = std::numeric_limits<int>::max(), bool keep_empty_parts = true);
std::vector<std::string> splitTopic(const std::string &topic);

bool isValidUtf8Generic(const std::string &s, bool alsoCheckInvalidPublishChars = false);
bool isValidUtf8(const std::string &s, bool alsoCheckInvalidPublishChars = false);

bool strContains(const std::string &s, const std::string &needle);

bool isValidShareName(const std::string &s);
bool isValidPublishPath(const std::string &s);
bool isValidSubscribePath(const std::string &s);
bool containsDangerousCharacters(const std::string &s);

void ltrim(std::string &s);
void rtrim(std::string &s);
void trim(std::string &s);
bool startsWith(const std::string &s, const std::string &needle);
std::string &rtrim(std::string &s, unsigned char c);

std::string getSecureRandomString(const ssize_t len);
std::string str_tolower(std::string s);
bool stringTruthiness(const std::string &val);
bool isPowerOfTwo(int val);

bool parseHttpHeader(CirBuf &buf, std::string &websocket_key, int &websocket_version, std::string &subprotocol, std::string &xRealIp);

std::vector<char> base64Decode(const std::string &s);
std::string base64Encode(const unsigned char *input, const int length);
std::string generateWebsocketAcceptString(const std::string &websocketKey);

std::string generateInvalidWebsocketVersionHttpHeaders(const int wantedVersion);
std::string generateBadHttpRequestReponse(const std::string &msg);
std::string generateWebsocketAnswer(const std::string &acceptString, const std::string &subprotocol);

void testSsl(const std::string &fullchain, const std::string &privkey);
void testSslVerifyLocations(const std::string &caFile, const std::string &caDir, const std::string &error);

std::string formatString(const std::string str, ...);

std::string_view dirnameOf(std::string_view fname);

BindAddr getBindAddr(int family, const std::string &bindAddress, int port);

ssize_t getFileSize(const std::string &path);

std::string sockaddrToString(const struct sockaddr *addr);

template<typename ex> void checkWritableDir(const std::string &path)
{
    if (path.empty())
        throw ex("Dir path to check is an empty string.");

    if (access(path.c_str(), W_OK) != 0)
    {
        std::string msg = formatString("Path '%s' is not there or not writable", path.c_str());
        throw ex(msg);
    }

    struct stat statbuf;
    memset(&statbuf, 0, sizeof(struct stat));
    if (stat(path.c_str(), &statbuf) < 0)
    {
        // We checked for W_OK above, so this shouldn't happen.
        std::string msg = formatString("Error getting information about '%s'.", path.c_str());
        throw ex(msg);
    }

    if (!S_ISDIR(statbuf.st_mode))
    {
        std::string msg = formatString("Path '%s' is not a directory.", path.c_str());
        throw ex(msg);
    }
}

std::string websocketCloseCodeToString(uint16_t code);

std::string protocolVersionString(ProtocolVersion p);

uint32_t ageFromTimePoint(const std::chrono::time_point<std::chrono::steady_clock> &point);
std::chrono::time_point<std::chrono::steady_clock> timepointFromAge(const uint32_t age);

ReasonCodes authResultToReasonCode(AuthResult authResult);

int maskAllSignalsCurrentThread();

void parseSubscriptionShare(std::vector<std::string> &subtopics, std::string &shareName);

std::string timestampWithMillis();

template<class T>
T get_random_int()
{
    std::vector<T> buf(1);
    // We use urandom, so we don't have check for blocking / interrupted conditions.
    if (getrandom(buf.data(), sizeof(T), 0) < 0)
        throw std::runtime_error(strerror(errno));
    T val = buf.at(0);
    return val;
}

void exceptionOnNonMqtt(const std::vector<char> &data);


#endif // UTILS_H