simple_archive - Eiffel Library Documentation

Overview

simple_archive provides Eiffel applications with file archiving capabilities. SIMPLE_TAR wraps ISE's compression library for TAR archives. SIMPLE_ZIP uses minizip-ng 4.0.10 (May 2025) for modern ZIP support with in-memory operations ideal for XLSX file handling.

Part of the simple_* ecosystem of focused, single-purpose Eiffel libraries with full Design by Contract support.

Quick Start

Installation

Set environment variable and add to your ECF:

-- Set SIMPLE_EIFFEL=D:\prod
<library name="simple_archive" location="$SIMPLE_EIFFEL/simple_archive/simple_archive.ecf"/>

Creating a ZIP Archive

local
    zip: SIMPLE_ZIP
do
    create zip.make

    -- Create archive with in-memory content
    zip.begin_create ("output.zip")
    zip.add_entry_from_string ("path/in/zip.xml", xml_content)
    zip.add_entry_from_string ("another/file.txt", text_content)
    zip.end_create
end

Extracting from ZIP

local
    zip: SIMPLE_ZIP
    content: detachable STRING
do
    create zip.make

    -- Check if valid archive
    if zip.is_valid_archive ("input.zip") then
        -- Extract specific entry
        content := zip.extract_entry ("input.zip", "path/in/zip.xml")

        -- List all entries
        across zip.list_archive ("input.zip") as entry loop
            print (entry)
        end
    end
end

Features

TAR Archives

Create and extract TAR archives via ISE compression library.

ZIP Archives

Create and extract ZIP archives via minizip-ng 4.0.10.

In-Memory Operations

Build archives from string content without temporary files.

Archive Listing

List contents without extraction for inspection.

Design by Contract

Full preconditions, postconditions, and class invariants.

Void Safety

Fully void-safe implementation with proper attached/detachable handling.

API Reference

SIMPLE_ZIP

Feature	Description
`make`	Create ZIP helper
`begin_create (path)`	Start creating new ZIP archive
`add_entry_from_string (name, content)`	Add entry with string content
`end_create`	Finalize and write ZIP file
`list_archive (path)`	List all entries in archive
`extract_entry (path, name)`	Extract entry content as string
`archive_contains (path, name)`	Check if archive contains entry
`is_valid_archive (path)`	Check if file is valid ZIP
`has_error`	Check if last operation failed
`last_error`	Error message from last operation

SIMPLE_TAR

Feature	Description
`create_archive (path, files)`	Create TAR from files
`extract_archive (path, dest)`	Extract TAR to directory
`list_archive (path)`	List TAR contents

Dependencies

simple_compression - ISE library for TAR support
minizip-ng 4.0.10 - Bundled for ZIP support
zlib - ISE library for compression backend