Archive/Zip/Reader.cpp

/*
 * Copyright(c) Sophist Solutions, Inc. 1990-2025.  All rights reserved
 */
#include "Stroika/Foundation/StroikaPreComp.h"
 
#if qStroika_HasComponent_zlib
#include <zlib.h>
#endif
 
#include "Stroika/Foundation/Characters/Format.h"
#include "Stroika/Foundation/DataExchange/Archive/Zip/Private_minizip_.h"
#include "Stroika/Foundation/Execution/Finally.h"
#include "Stroika/Foundation/Streams/MemoryStream.h"
 
#include "Reader.h"
 
using namespace Stroika::Foundation;
using namespace Stroika::Foundation::Characters;
using namespace Stroika::Foundation::Containers;
using namespace Stroika::Foundation::DataExchange;
using namespace Stroika::Foundation::DataExchange::Archive;
using namespace Stroika::Foundation::Execution;
using namespace Stroika::Foundation::Streams;
 
using std::byte;
 
#if qStroika_HasComponent_zlib
using namespace Stroika::Foundation::DataExchange::Archive::Zip::PrivateMinizip_;
 
namespace {
    void ThrowIfMinizipErr_ (int err, const String& doing)
    {
        if (err != UNZ_OK) [[unlikely]] {
            Throw (RuntimeErrorException{Format ("error {} with zipfile in {}"_f, err, doing)});
        }
    }
}
 
namespace {
    struct MyZipLibInStream_ final : zlib_filefunc64_def {
        InputStream::Ptr<byte> fInStream_;
#if qStroika_Foundation_Debug_AssertionsChecked
        bool fOpened_{false};
#endif
        MyZipLibInStream_ (const InputStream::Ptr<byte>& in)
            : fInStream_{in}
        {
            this->zopen64_file = [] (voidpf opaqueStream, const void* /*filename*/, int /*mode*/) -> voidpf {
                MyZipLibInStream_* myThis = reinterpret_cast<MyZipLibInStream_*> (opaqueStream);
#if qStroika_Foundation_Debug_AssertionsChecked
                Assert (not myThis->fOpened_);
                myThis->fOpened_ = true;
#endif
                return myThis;
            };
            this->zread_file = [] (voidpf opaqueStream, [[maybe_unused]] voidpf stream, void* buf, uLong size) -> uLong {
                Require (opaqueStream == stream); // our use is one stream per zlib_filefunc64_def object
                MyZipLibInStream_* myThis = reinterpret_cast<MyZipLibInStream_*> (opaqueStream);
#if qStroika_Foundation_Debug_AssertionsChecked
                Assert (myThis->fOpened_);
#endif
                size_t sz = myThis->fInStream_.ReadBlocking (span{reinterpret_cast<byte*> (buf), size}).size ();
                Assert (sz <= size);
                return static_cast<uLong> (sz);
            };
            this->zwrite_file = [] (voidpf /*opaque*/, voidpf /*stream*/, const void* /*buf*/, uLong /*size*/) -> uLong {
                RequireNotReached (); // read only zip
                return static_cast<uLong> (UNZ_PARAMERROR);
            };
            this->ztell64_file = [] (voidpf opaqueStream, [[maybe_unused]] voidpf stream) -> ZPOS64_T {
                Require (opaqueStream == stream); // our use is one stream per zlib_filefunc64_def object
                MyZipLibInStream_* myThis = reinterpret_cast<MyZipLibInStream_*> (opaqueStream);
#if qStroika_Foundation_Debug_AssertionsChecked
                Assert (myThis->fOpened_);
#endif
                return myThis->fInStream_.GetOffset ();
            };
            this->zseek64_file = [] (voidpf opaqueStream, [[maybe_unused]] voidpf stream, ZPOS64_T offset, int origin) -> long {
                Require (opaqueStream == stream); // our use is one stream per zlib_filefunc64_def object
                MyZipLibInStream_* myThis = reinterpret_cast<MyZipLibInStream_*> (opaqueStream);
#if qStroika_Foundation_Debug_AssertionsChecked
                Assert (myThis->fOpened_);
#endif
                switch (origin) {
                    case ZLIB_FILEFUNC_SEEK_SET:
                        myThis->fInStream_.Seek (offset);
                        break;
                    case ZLIB_FILEFUNC_SEEK_CUR:
                        myThis->fInStream_.Seek (eFromCurrent, offset);
                        break;
                    case ZLIB_FILEFUNC_SEEK_END:
                        myThis->fInStream_.Seek (eFromEnd, offset);
                        break;
                    default:
                        AssertNotReached ();
                        return UNZ_PARAMERROR;
                }
                return UNZ_OK;
            };
            this->zclose_file = [] ([[maybe_unused]] voidpf opaqueStream, [[maybe_unused]] voidpf stream) -> int {
#if qStroika_Foundation_Debug_AssertionsChecked
                Require (opaqueStream == stream); // our use is one stream per zlib_filefunc64_def object
                MyZipLibInStream_* myThis = reinterpret_cast<MyZipLibInStream_*> (opaqueStream);
                Assert (myThis->fOpened_);
                myThis->fOpened_ = false;
#endif
                return UNZ_OK;
            };
            this->zerror_file = [] (voidpf opaqueStream, [[maybe_unused]] voidpf stream) -> int {
                Require (opaqueStream == stream); // our use is one stream per zlib_filefunc64_def object
                [[maybe_unused]] MyZipLibInStream_* myThis = reinterpret_cast<MyZipLibInStream_*> (opaqueStream);
#if qStroika_Foundation_Debug_AssertionsChecked
                Assert (myThis->fOpened_);
#endif
                return UNZ_OK; // @todo - see what this means?
            };
            this->opaque = this;
        }
        ~MyZipLibInStream_ ()
        {
#if qStroika_Foundation_Debug_AssertionsChecked
            Assert (not fOpened_);
#endif
        }
    };
}
 
namespace {
 
    struct Rep_ final : public Reader::IRep {
        MyZipLibInStream_ fInSeekStream_;
        unzFile           fZipFile_;
 
        Rep_ (const InputStream::Ptr<byte>& in)
            : fInSeekStream_{in}
            , fZipFile_{unzOpen2_64 ("", &fInSeekStream_)}
        {
            if (fZipFile_ == nullptr) [[unlikely]] {
                static const RuntimeErrorException kException_{"failed to open zipfile"sv};
                Throw (kException_);
            }
        }
        ~Rep_ ()
        {
            AssertNotNull (fZipFile_);
            unzClose (fZipFile_);
        }
        virtual Set<String> GetContainedFiles () const override
        {
            Set<String>       result;
            unz_global_info64 gi;
            ThrowIfMinizipErr_ (unzGetGlobalInfo64 (fZipFile_, &gi), "unzGetGlobalInfo64"sv);
            for (size_t i = 0; i < gi.number_entry; i++) {
                char            filename_inzip[10 * 1024];
                unz_file_info64 file_info;
                //uLong           ratio = 0;
                //const char* string_method;
                //char charCrypt = ' ';
                ThrowIfMinizipErr_ (::unzGetCurrentFileInfo64 (fZipFile_, &file_info, filename_inzip, sizeof (filename_inzip), NULL, 0, NULL, 0),
                                    "unzGetGlobalInfo64"sv);
                if ((i + 1) < gi.number_entry) {
                    ThrowIfMinizipErr_ (::unzGoToNextFile_ (fZipFile_), "unzGoToNextFile_"sv);
                }
                //tmphack
                if (filename_inzip[::strlen (filename_inzip) - 1] == '/') {
                    continue; // only list files - not directories for now
                }
                // From https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT, must check bit 11 to see if really unicode, but not sure what code page if not unicode so just assume unicode!
                result.Add (String::FromUTF8 (filename_inzip));
            }
#if 0
        // Keep temporarily, because we will want a traversal variant that captures this extra info
        uLong i;
        unz_global_info64 gi;
        int err;
 
        err = unzGetGlobalInfo64(uf, &gi);
        if (err != UNZ_OK)
            printf("error %d with zipfile in unzGetGlobalInfo \n", err);
        printf("  Length  Method     Size Ratio   Date    Time   CRC-32     Name\n");
        printf("  ------  ------     ---- -----   ----    ----   ------     ----\n");
        for (i = 0; i < gi.number_entry; ++i) {
            char filename_inzip[256];
            unz_file_info64 file_info;
            uLong ratio = 0;
            const char* string_method;
            char charCrypt = ' ';
            err = unzGetCurrentFileInfo64(uf, &file_info, filename_inzip, sizeof(filename_inzip), NULL, 0, NULL, 0);
            if (err != UNZ_OK) {
                printf("error %d with zipfile in unzGetCurrentFileInfo\n", err);
                break;
            }
            if (file_info.uncompressed_size > 0)
                ratio = (uLong)((file_info.compressed_size * 100) / file_info.uncompressed_size);
 
            /* display a '*' if the file is crypted */
            if ((file_info.flag & 1) != 0)
                charCrypt = '*';
 
            if (file_info.compression_method == 0)
                string_method = "Stored";
            else if (file_info.compression_method == Z_DEFLATED) {
                uInt iLevel = (uInt)((file_info.flag & 0x6) / 2);
                if (iLevel == 0)
                    string_method = "Defl:N";
                else if (iLevel == 1)
                    string_method = "Defl:X";
                else if ((iLevel == 2) or (iLevel == 3))
                    string_method = "Defl:F"; /* 2:fast , 3 : extra fast*/
            }
            else if (file_info.compression_method == Z_BZIP2ED) {
                string_method = "BZip2 ";
            }
            else
                string_method = "Unkn. ";
 
            Display64BitsSize(file_info.uncompressed_size, 7);
            printf("  %6s%c", string_method, charCrypt);
            Display64BitsSize(file_info.compressed_size, 7);
            printf(" %3lu%%  %2.2lu-%2.2lu-%2.2lu  %2.2lu:%2.2lu  %8.8lx   %s\n",
                   ratio,
                   (uLong)file_info.tmu_date.tm_mon + 1,
                   (uLong)file_info.tmu_date.tm_mday,
                   (uLong)file_info.tmu_date.tm_year % 100,
                   (uLong)file_info.tmu_date.tm_hour, (uLong)file_info.tmu_date.tm_min,
                   (uLong)file_info.crc, filename_inzip);
            if ((i + 1) < gi.number_entry) {
                err = unzGoToNextFile_ (uf);
                if (err != UNZ_OK) {
                    printf("error %d with zipfile in unzGoToNextFile\n", err);
                    break;
                }
            }
        }
 
        for (unsigned int i = 0; i < fDB_.NumFiles; i++) {
            if (not SzArEx_IsDir (&fDB_, i)) {
                size_t nameLen = ::SzArEx_GetFileNameUtf16 (&fDB_, i, nullptr);
                if (nameLen < 1) {
                    break;
                }
                Memory::StackBuffer<char16_t> fileName {Memory::eUninitiialized, nameLen};
                size_t z = ::SzArEx_GetFileNameUtf16 (&fDB_, i, reinterpret_cast<UInt16*> (&fileName[0]));
                result.Add (String{&fileName[0]});
            }
        }
#endif
            return result;
        }
        virtual Memory::BLOB GetData (const String& fileName) const override
        {
            // See comments in GetContainedFiles about filename character encoding
            if (unzLocateFile_ (fZipFile_, fileName.AsUTF8<string> ().c_str (), 1) != UNZ_OK) [[unlikely]] {
                Throw (RuntimeErrorException{Format ("File '{}' not found"_f, fileName)});
            }
            const char*             password = nullptr;
            int                     err      = unzOpenCurrentFilePassword (fZipFile_, password);
            [[maybe_unused]] auto&& cleanup  = Finally ([this] () noexcept { unzCloseCurrentFile_ (fZipFile_); });
            MemoryStream::Ptr<byte> tmpBuf   = MemoryStream::New<byte> ();
            do {
                byte buf[10 * 1024];
                err = unzReadCurrentFile_ (fZipFile_, buf, static_cast<unsigned int> (std::size (buf)));
                if (err < 0) [[unlikely]] {
                    Throw (RuntimeErrorException{Format (L"File '{}' error {} extracting"_f, fileName, err)});
                }
                else if (err > 0) {
                    Assert (static_cast<size_t> (err) <= std::size (buf));
                    tmpBuf.Write (span{buf, static_cast<size_t> (err)});
                }
            } while (err > 0);
            return tmpBuf.As<Memory::BLOB> ();
        }
    };
}
 
/*
 ********************************************************************************
 ***************** DataExchange::Archive::Zip::Reader::New **********************
 ********************************************************************************
 */
Archive::Reader::Ptr Archive::Zip::Reader::New (const InputStream::Ptr<byte>& readFrom)
{
    return Archive::Reader::Ptr{make_shared<Rep_> (readFrom)};
}
#endif