dotnet-installer/src/corehost/src/utils.cpp

#include "utils.h"

bool ends_with(const pal::string_t& value, const pal::string_t& suffix)
{
    return (0 == value.compare(value.length() - suffix.length(), suffix.length(), suffix));
}

bool find_coreclr(const pal::string_t& appbase, pal::string_t& recv)
{
    pal::string_t candidate;
    // Check if it exists in the appbase
    candidate.assign(appbase);
    append_path(candidate, LIBCORECLR_NAME);
    if (pal::file_exists(candidate))
    {
        recv.assign(appbase);
        return true;
    }

    // TODO: Have a cleaner search strategy that supports multiple versions
    // Search the PATH
    pal::string_t path;
    if (!pal::getenv(_X("PATH"), path))
    {
        return false;
    }
    pal::stringstream_t path_stream(path);
    pal::string_t entry;
    while (std::getline(path_stream, entry, PATH_SEPARATOR))
    {
        candidate.assign(entry);
        append_path(candidate, LIBCORECLR_NAME);
        if (pal::file_exists(candidate))
        {
            recv.assign(entry);
            return true;
        }
    }
    return false;
}

void append_path(pal::string_t& path1, const pal::char_t* path2)
{
    if (pal::is_path_rooted(path2))
    {
        path1.assign(path2);
    }
    else
    {
        if (path1.back() != DIR_SEPARATOR)
        {
            path1.push_back(DIR_SEPARATOR);
        }
        path1.append(path2);
    }
}

pal::string_t get_executable(const pal::string_t& filename)
{
    pal::string_t result(filename);

    if (ends_with(result, _X(".exe")))
    {
        // We need to strip off the old extension
        result.erase(result.length() - 4);
    }

    return result;
}

pal::string_t get_filename(const pal::string_t& path)
{
    // Find the last dir separator
    auto path_sep = path.find_last_of(DIR_SEPARATOR);
    if (path_sep == pal::string_t::npos)
    {
        return pal::string_t(path);
    }

    return path.substr(path_sep + 1);
}

pal::string_t get_directory(const pal::string_t& path)
{
    // Find the last dir separator
    auto path_sep = path.find_last_of(DIR_SEPARATOR);
    if (path_sep == pal::string_t::npos)
    {
        return pal::string_t(path);
    }

    return path.substr(0, path_sep);
}