rocm-systems/source/lib/common/xml.hpp

/******************************************************************************
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#pragma once

#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include <fstream>
#include <iostream>
#include <list>
#include <map>
#include <memory>
#include <string>
#include <vector>

namespace xml
{
class Xml
{
public:
    using token_t = std::vector<char>;

    struct level_t;
    using node_vect_t = std::vector<std::shared_ptr<level_t>>;
    using node_list_t = std::list<std::shared_ptr<level_t>>;

    using nodes_t = node_vect_t;
    using opts_t  = std::map<std::string, std::string>;
    struct level_t
    {
        std::string                    tag;
        nodes_t                        nodes;
        opts_t                         opts;
        std::shared_ptr<const level_t> copy;
    };
    using nodes_vec_t = std::vector<std::shared_ptr<level_t>>;
    using map_t       = std::map<std::string, nodes_vec_t>;

    enum
    {
        DECL_STATE,
        BODY_STATE
    };

    static std::shared_ptr<Xml> Create(const std::string& file_name, const Xml* obj = nullptr)
    {
        auto xml = std::make_shared<Xml>(file_name, obj);
        if(xml != nullptr)
        {
            if(xml->Init() != false)
            {
                const std::size_t pos = file_name.rfind('/');
                const std::string path =
                    (pos != std::string::npos) ? file_name.substr(0, pos + 1) : "";

                xml->PreProcess();
                nodes_t incl_nodes;
                for(const auto& node : xml->GetNodes("top.include"))
                {
                    if(node->opts.find("touch") == node->opts.end())
                    {
                        node->opts["touch"] = "";
                        incl_nodes.push_back(node);
                    }
                }
                for(const auto& incl : incl_nodes)
                {
                    const std::string& incl_name = path + incl->opts["file"];
                    auto               ixml      = Create(incl_name, xml.get());
                    if(!ixml)
                    {
                        xml.reset();
                        break;
                    }
                }
                if(xml)
                {
                    xml->Process();
                }
            }
        }

        return xml;
    }

    std::string GetName() { return file_name_; }

    // clang-tidy incorrectly marks these functions as being staticable. They are not.
    // NOLINTBEGIN
    void AddExpr(const std::string& full_tag, const std::string& name, const std::string& expr)
    {
        const std::size_t pos       = full_tag.rfind('.');
        const std::size_t pos1      = (pos == std::string::npos) ? 0 : pos + 1;
        const std::string level_tag = full_tag.substr(pos1);
        auto              level     = std::make_shared<level_t>();
        (*map_)[full_tag].push_back(level);
        level->tag          = level_tag;
        level->opts["name"] = name;
        level->opts["expr"] = expr;
    }

    void AddConst(const std::string& full_tag, const std::string& name, const uint64_t& val)
    {
        std::ostringstream oss;
        oss << val;
        AddExpr(full_tag, name, oss.str());
    }
    // NOLINTEND

    nodes_t      GetNodes(const std::string& global_tag) { return (*map_)[global_tag]; }
    const map_t& GetAllNodes() { return (*map_); }

    template <class F>
    F ForEach(const F& f_i)
    {
        F f = f_i;
        if(map_)
        {
            for(auto& entry : *map_)
            {
                for(auto node : entry.second)
                {
                    if(f.fun(entry.first, node) == false) break;
                }
            }
        }
        return f;
    }

    template <class F>
    F ForEach(const F& f_i) const
    {
        F f = f_i;
        if(map_)
        {
            for(auto& entry : *map_)
            {
                for(const auto& node : entry.second)
                {
                    if(f.fun(entry.first, node) == false) break;
                }
            }
        }
        return f;
    }

    struct print_func
    {
        static bool fun(const std::string& global_tag, const std::shared_ptr<level_t>& node)
        {
            std::cout << global_tag << ":" << std::endl;
            for(auto& opt : node->opts)
            {
                std::cout << global_tag << "." << opt.first << " = " << opt.second << std::endl;
            }
            return true;
        }
    };

    void Print() const
    {
        std::cout << "XML file '" << file_name_ << "':" << std::endl;
        ForEach(print_func());
    }

    Xml(std::string file_name, const Xml* obj)
    : file_name_(std::move(file_name))
    , state_(BODY_STATE)
    {
        if(obj != nullptr)
        {
            map_      = obj->map_;
            level_    = obj->level_;
            included_ = true;
        }
    }

    ~Xml()
    {
        for(auto& x : stack_)
        {
            x->nodes.clear();
            x->copy.reset();
        }
        if(!map_) return;
        for(auto& [_, nodes] : *map_)
        {
            for(auto& node : nodes)
            {
                node->nodes.clear();
                node->copy.reset();
            }
        }
    }

private:
    bool Init()
    {
        fd_ = open(file_name_.c_str(), O_RDONLY);
        if(fd_ == -1)
        {
            // perror((std::string("open XML file ") + file_name_).c_str());
            return false;
        }

        if(map_ == nullptr)
        {
            map_ = std::make_unique<map_t>();
            AddLevel("top");
        }

        return true;
    }

    void PreProcess()
    {
        uint32_t ind = 0;
        char     buf[kBufSize];
        bool     error = false;

        while(true)
        {
            const uint32_t pos  = lseek(fd_, 0, SEEK_CUR);
            uint32_t       size = read(fd_, buf, kBufSize);
            if(size <= 0) break;
            buf[size - 1] = '\0';

            if(strncmp(buf, "#include \"", 10) == 0)
            {
                for(ind = 0; (ind < size) && (buf[ind] != '\n'); ++ind)
                {}
                if(ind < size)
                {
                    buf[ind] = '\0';
                    size     = ind;
                    lseek(fd_, pos + ind + 1, SEEK_SET);
                }

                for(ind = 10; (ind < size) && (buf[ind] != '"'); ++ind)
                {}
                if(ind == size)
                {
                    error = true;
                    break;
                }
                buf[ind] = '\0';

                AddLevel("include");
                AddOption("file", &buf[10]);
                UpLevel();
            }
        }

        if(error)
        {
            fprintf(stderr, "XML PreProcess failed, line '%s'\n", buf);
            abort();
        }

        lseek(fd_, 0, SEEK_SET);
    }

    void Process()
    {
        token_t remainder;

        while(true)
        {
            token_t token = (!remainder.empty()) ? remainder : NextToken();
            remainder.clear();

            // token_t token1 = token;
            // token1.push_back('\0');
            // std::cout << ">>> " << &token1[0] << std::endl;

            // End of file
            if(token.empty()) break;

            switch(state_)
            {
                case BODY_STATE:
                    if(token[0] == '<')
                    {
                        bool     node_begin = true;
                        unsigned ind        = 1;
                        if(token[1] == '/')
                        {
                            node_begin = false;
                            ++ind;
                        }

                        unsigned i = ind;
                        while(i < token.size())
                        {
                            if(token[i] == '>') break;
                            ++i;
                        }
                        for(unsigned j = i + 1; j < token.size(); ++j)
                            remainder.push_back(token[j]);

                        if(i == token.size())
                        {
                            if(node_begin)
                                state_ = DECL_STATE;
                            else
                                BadFormat(token);
                            token.push_back('\0');
                        }
                        else
                        {
                            token[i] = '\0';
                        }

                        const char* tag = &token[ind];
                        if(node_begin)
                        {
                            AddLevel(tag);
                        }
                        else
                        {
                            Inherit(GetOption("base"));

                            if(strncmp(CurrentLevel().c_str(), tag, strlen(tag)) != 0)
                            {
                                token.back() = '>';
                                BadFormat(token);
                            }
                            UpLevel();
                        }
                    }
                    else
                    {
                        BadFormat(token);
                    }
                    break;
                case DECL_STATE:
                    if(token[0] == '>')
                    {
                        state_ = BODY_STATE;
                        for(unsigned j = 1; j < token.size(); ++j)
                            remainder.push_back(token[j]);
                        continue;
                    }
                    else
                    {
                        token.push_back('\0');
                        unsigned j = 0;
                        for(j = 0; j < token.size(); ++j)
                            if(token[j] == '=') break;
                        if(j == token.size()) BadFormat(token);
                        token[j]                = '\0';
                        const std::string key   = token.data();
                        const std::string value = &token[j + 1];
                        AddOption(key, value);
                    }
                    break;
                default:
                    std::cout << "XML parser error: wrong state: " << state_ << std::endl;
                    abort();
            }
        }
    }

    bool SpaceCheck() const
    {
        bool cond = ((buffer_[index_] == ' ') || (buffer_[index_] == '\t'));
        return cond;
    }

    bool LineEndCheck()
    {
        bool found = false;
        if(buffer_[index_] == '\n')
        {
            buffer_[index_] = ' ';
            ++file_line_;
            found    = true;
            comment_ = false;
        }
        else if(comment_ || (buffer_[index_] == '#'))
        {
            found    = true;
            comment_ = true;
        }
        return found;
    }

    token_t NextToken()
    {
        token_t token;
        bool    in_string    = false;
        bool    special_symb = false;

        while(true)
        {
            if(data_size_ == 0)
            {
                data_size_ = read(fd_, buffer_, kBufSize);
                if(data_size_ <= 0) break;
            }

            if(token.empty())
            {
                while((index_ < data_size_) && (SpaceCheck() || LineEndCheck()))
                {
                    ++index_;
                }
            }
            while((index_ < data_size_) && (in_string || !(SpaceCheck() || LineEndCheck())))
            {
                const char symb      = buffer_[index_];
                bool       skip_symb = false;

                switch(symb)
                {
                    case '\\':
                        if(special_symb)
                        {
                            special_symb = false;
                        }
                        else
                        {
                            special_symb = true;
                            skip_symb    = true;
                        }
                        break;
                    case '"':
                        if(special_symb)
                        {
                            special_symb = false;
                        }
                        else
                        {
                            in_string = !in_string;
                            if(!in_string)
                            {
                                buffer_[index_] = ' ';
                                --index_;
                            }
                            skip_symb = true;
                        }
                        break;
                }

                if(!skip_symb) token.push_back(symb);
                ++index_;
            }

            if(index_ == data_size_)
            {
                index_     = 0;
                data_size_ = 0;
            }
            else
            {
                if(special_symb || in_string) BadFormat(token);
                break;
            }
        }

        return token;
    }

    void BadFormat(token_t token)
    {
        token.push_back('\0');
        std::cout << "Error: " << file_name_ << ", line " << file_line_ << ", bad XML token '"
                  << token.data() << "'" << std::endl;
        abort();
    }

    void AddLevel(const std::string& tag)
    {
        auto level = std::make_shared<level_t>();
        level->tag = tag;
        if(level_)
        {
            level_->nodes.push_back(level);
            stack_.push_back(level_);
        }
        level_ = level;

        std::string global_tag = GlobalTag(tag);
        (*map_)[global_tag].push_back(level_);
    }

    void UpLevel()
    {
        level_ = stack_.back();
        stack_.pop_back();
    }

    void Copy(const std::shared_ptr<level_t>& from, const std::shared_ptr<level_t>& to)
    {
        auto level = to;
        if(level == nullptr)
        {
            AddLevel(from->tag);
            level = level_;
        }
        level->copy = from;
        level->opts = from->opts;

        for(const auto& node : from->nodes)
        {
            bool              found      = false;
            const std::string name       = GetOption("name", node);
            const std::string global_tag = GlobalTag(level->tag) + "." + node->tag;
            for(const auto& item : (*map_)[global_tag])
            {
                if((name == GetOption("name", item)) || (node == item->copy))
                {
                    found = true;
                    break;
                }
            }
            if(found == false) Copy(node, nullptr);
        }

        if(to == nullptr) UpLevel();
    }

    void Inherit(const std::string& tag)
    {
        if(!tag.empty())
        {
            const std::string global_tag = GlobalTag(tag);
            auto              it         = map_->find(global_tag);
            if(it == map_->end())
            {
                fprintf(stderr,
                        "Node \"%s\": Base not found \"%s\"\n",
                        level_->tag.c_str(),
                        tag.c_str());
                abort();
            }
            for(const auto& node : it->second)
            {
                Copy(node, level_);
            }
        }
    }

    std::string CurrentLevel() const { return level_->tag; }

    std::string GlobalTag(const std::string& tag) const
    {
        std::string global_tag;
        for(const auto& level : stack_)
        {
            global_tag += level->tag + ".";
        }
        global_tag += tag;
        return global_tag;
    }

    void AddOption(const std::string& key, const std::string& value) { level_->opts[key] = value; }
    std::string GetOption(const std::string& key, std::shared_ptr<const level_t> level = nullptr)
    {
        level   = (level != nullptr) ? level : level_;
        auto it = level->opts.find(key);
        return (it != level->opts.end()) ? it->second : "";
    }

    const std::string file_name_;
    unsigned          file_line_{0};
    int               fd_;

    static const size_t kBufSize = 256;
    char                buffer_[kBufSize];

    unsigned                              data_size_{0};
    unsigned                              index_{0};
    unsigned                              state_{0};
    bool                                  comment_{false};
    std::vector<std::shared_ptr<level_t>> stack_;
    bool                                  included_{false};
    std::shared_ptr<level_t>              level_;
    std::shared_ptr<map_t>                map_;
};

}  // namespace xml