API Plans
=========

Encryption
----------
* struct zip *zip_open_encrypted(const char *path, int flags, const char *password, int *errorp);
* int zip_set_encryption(struct zip *archive, zip_uint64_t idx, zip_uint16_t method, const char *password);
* void zip_set_archive_encryption(struct zip *archive, zip_uint16_t method, const char *password);

Prefixes
--------
For example for adding extractors for self-extracting zip archives.
* zip_set_archive_prefix(struct zip *za, const zip_uint8_t *data, zip_uint64_t length);
* const zip_uint8_t *zip_get_archive_prefix(struct zip *za, zip_uint64_t *lengthp);

API Issues
==========
! D zip_get_archive_comment has int *lenp argument.  Cleaner would be zip_uint32_t *.
	rename and fix.  which other functions for naming consistency?
! D rename remaining zip_XXX_{file,archive}_* to zip_{file,archive}_XXX_*?
* compression/crypt implementations: how to set error code on failure
* compression/crypt error messages a la ZIP_ER_ZLIB (no detailed info passing)
* check arguments for every entry point into libzip


Features
========
* progress callback for zip_close (called after each file written completely)
* function to copy file from one archive to another
* do not compress if storing is smaller
* set O_CLOEXEC flag after fopen and mkstemp

* I/O methods
* support streaming output (creating new archive to e.g. stdout)
* add functions to:
  . read/set ASCII file flag? (wiz: more general options?)
* zip_commit (to finish changes without closing archive)
* add custom compression function support
* zip_source_zip: allow rewinding
* zip_source_seek, zip_fseek
* zipcmp: add option for file content comparison
* zipcmp: compare bit flags if paranoid
* zipcmp: compare external attributes/opsys if paranoid
* zipcmp: compare last_mod if paranoid (or with separate flag?)
* consistency
  . for stored files, test compressed = uncompressed
  . data descriptor
  . local headers come before central dir

- support for old compression methods?????
- append to files (for self-extracting files)


Bugs
====
* embed stripped down old zlib for torrentzip
! ensure that nentries is small enough not to cause overflow (size_t for entry, uint64 for CD on disk)
* Xcode 32bit build uses 64bit config.h
* fix OpenSUSE i686 regression failures
* fix open_filename_duplicate_consistency.test to fail
* split zip archive torrentzip state from user requested torrentzip state
* check for limits imposed by format (central dir size, file size, extra fields, ...)
* _zip_u2d_time: handle localtime(3) failure
* POSIX: zip_open: check whether file can be created and fail if not
* POSIX: fix permissions of new file to match old one
* fix inconsistent usage of valid flags (not checked in many places)
* cdr == NULL -> ER_NOENT vs. idx > cdir->nentry -> ER_INVAL inconsistent (still there?)
* torrentzip broken on NetBSD/amd64 6.99
* torrentzip: check behaviour of files with empty name (size 0; file size > 0)


Cleanup
=======
* move compat refs from zipint.h to own file, and include that in zipint.h and src
* get rid of zip_get_{compression,encryption}_implementation
* use zip_*int*_t internally
* clean up lint(1) warnings?


Test Case Issues
================
* replace Text::Diff with own implementation
* use zipcmp -p?
* zip_open file less than EOCDLEN bytes long
* test calls against old API
* run regression tests also from CMake framework
* rename file to dir/ and vice versa (fails)
* fix comment test to be newline insensitive
* zip64 test case ideas (but how to provide comparison and input files?)
  Create files with:
  * compressed < 4GB, uncompressed > 4GB
  * compressed > 4GB
  * offset of file or central directory > 4GB
* check if http://bugs.python.org/issue20078 provides ideas for new tests

* (add, replace)
	add to empty zip
	add to existing zip
	add w/ existing file name [E]
	replace ok
	replace w/ illegal index [E]
	replace w/ deleted name [E]
	unchange added/replaced file
* (close)
	copy zip file
	open copy
	rename, delete, replace, add w/ new name, add w/ deleted name
	close
	zipcmp copy expected
	remove copy
* (error_get)
* (error_get_sys_type)
* (error_to_str)
* (extra_fields)
* (file_error_get)
* (file_strerror)
* (replace)
* (source_buffer)
* (source_file)
* (source_filep)
* (source_free)
* (source_function)
* (source_zip)
* (strerror)
* (unchange)
* (unchange_all)


I/O Methods
===========
One major headache for libzip portability (especially to Windows) is
I/O, i.e. reading and writing from the file system.  Also, there
have been requests to open zip archives from a memory buffer.  To
address these issues, we'll introduce an I/O abstraction layer.

  We'll reuse zip_source, since it already provides support for
the reading part, adding high level abstraction of the additional
operations needed. This way, newly written zip_sources can be used
both for adding files into an archive as well as for accessing archives
themselves.

Specifically, we'll add these commands:

ZIP_SOURCE_BEGIN_WRITE
        Prepare for writing.  The written data will replace all
        original data.  The file position is reset to 0.  (On POSIX
        systems, this will create a temporary file and open it for
        writing.)

ZIP_SOURCE_WRITE
        Write bytes of data, a la fwrite(3) (does not need to know
        anything about the zip archive structure).

ZIP_SOURCE_COMMIT_WRITE
        Used after all data has been written successfully. (On
        POSIX systems, this will replace the original file with
        the temporary file, adapting permissions etc.)
ZIP_SOURCE_ROLLBACK_WRITE
        because writing failed) to restore original data if possible;
        return an errohis will
        delete the temporary file.)

ZIP_SOURCE_SEEK
        Set position for next read or write, a la fseek(3).

ZIP_SOURCE_SUPPORTS
        Query which commands are supported for this stream.  If a
        file cannot be written to, this will report ZIP_SOURCE_BEGIN_WRITE
        as not supported, even if the source type would support
        write.  (This is used in zip_open to set global flags like
        ZIP_AFL_RDONLY.)

  We'll provide a zip_open variant that takes a zip_source argument
used for reading/writing archives.  Using an enhanced version of
zip_source_buffer, this can be used to read zip archives from memory.

  zip_open itself will create a source from the file using a
port-specific default implementation (POSIX vs. Windows vs. ...).

  Once the details are finalized, we'll ask for volunteers for writing
a Windows specific implementation.