init

Backend/src/main/java/com/gregor_lohaus/gtransfer/config/ConfigRuntimeHints.java

@@ -50,11 +50,6 @@ public class ConfigRuntimeHints implements RuntimeHintsRegistrar {
         MemberCategory.INVOKE_PUBLIC_CONSTRUCTORS,
         MemberCategory.ACCESS_DECLARED_FIELDS,
         MemberCategory.ACCESS_PUBLIC_FIELDS);
-    hints.reflection().registerType(UploadConfig.class,
-        MemberCategory.INVOKE_DECLARED_CONSTRUCTORS,
-        MemberCategory.INVOKE_PUBLIC_CONSTRUCTORS,
-        MemberCategory.ACCESS_DECLARED_FIELDS,
-        MemberCategory.ACCESS_PUBLIC_FIELDS);
     hints.reflection().registerType(TypeAdapter.class,
         MemberCategory.ACCESS_DECLARED_FIELDS,
         MemberCategory.ACCESS_PUBLIC_FIELDS);

Backend/src/main/java/com/gregor_lohaus/gtransfer/config/DefaultConfig.java

@@ -10,7 +10,6 @@ import com.gregor_lohaus.gtransfer.config.types.ServletConfig;
 import com.gregor_lohaus.gtransfer.config.types.SpringConfig;
 import com.gregor_lohaus.gtransfer.config.types.StorageService;
 import com.gregor_lohaus.gtransfer.config.types.StorageServiceType;
-import com.gregor_lohaus.gtransfer.config.types.UploadConfig;
 
 public class DefaultConfig {
   public static final Config config;
@@ -43,12 +42,6 @@ public class DefaultConfig {
     sc.servletConfig = svc;
 
     c.springConfig = sc;
-
-    UploadConfig uc = new UploadConfig();
-    uc.maxDownloadLimit = 100;
-    uc.maxExpiryDays = 30;
-    c.uploadConfig = uc;
-
     config = c;
   }
 }

Backend/src/main/java/com/gregor_lohaus/gtransfer/config/types/Config.java

@@ -11,6 +11,4 @@ public class Config implements TomlSerializable {
   public SpringConfig springConfig;
   @Nested(name = "storageService")
   public StorageService storageService;
-  @Nested(name = "upload")
-  public UploadConfig uploadConfig;
 }

Backend/src/main/java/com/gregor_lohaus/gtransfer/config/types/UploadConfig.java

@@ -1,12 +0,0 @@
-package com.gregor_lohaus.gtransfer.config.types;
-
-import com.gregor_lohaus.gtransfer.config.annotations.Property;
-
-import io.github.wasabithumb.jtoml.serial.TomlSerializable;
-
-public class UploadConfig implements TomlSerializable {
-  @Property(name = "maxDownloadLimit")
-  public Integer maxDownloadLimit;
-  @Property(name = "maxExpiryDays")
-  public Integer maxExpiryDays;
-}

Backend/src/main/java/com/gregor_lohaus/gtransfer/controller/UploadController.java

@@ -1,63 +1,37 @@
 package com.gregor_lohaus.gtransfer.controller;
 
 import java.io.IOException;
-import java.time.LocalDateTime;
+import java.util.Map;
 
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.stereotype.Controller;
-import org.springframework.ui.Model;
-import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
 import com.gregor_lohaus.gtransfer.model.File;
 import com.gregor_lohaus.gtransfer.model.FileRepository;
 import com.gregor_lohaus.gtransfer.services.filewriter.AbstractStorageService;
 
-@Controller
+@RestController
 public class UploadController {
 
-    @Value("${gtransfer-config.upload.maxDownloadLimit:100}")
-    private Integer maxDownloadLimit;
-
-    @Value("${gtransfer-config.upload.maxExpiryDays:30}")
-    private Integer maxExpiryDays;
-
     @Autowired
     private AbstractStorageService storageService;
 
     @Autowired
     private FileRepository fileRepository;
 
-    @GetMapping("/upload/options")
-    public String options(@RequestParam String name, Model model) {
-        model.addAttribute("name", name);
-        model.addAttribute("maxExpiryDays", maxExpiryDays);
-        model.addAttribute("maxDownloadLimit", maxDownloadLimit);
-        return "upload/options :: form";
-    }
-
     @PostMapping("/upload")
-    public String upload(
+    public ResponseEntity<Map<String, String>> upload(
             @RequestParam("file") MultipartFile file,
             @RequestParam("hash") String hash,
-            @RequestParam("name") String name,
-            @RequestParam(required = false) Integer expiryDays,
-            @RequestParam(required = false) Integer downloadLimit,
-            Model model) throws IOException {
+            @RequestParam("name") String name) throws IOException {
 
         storageService.put(hash, file.getBytes());
+        fileRepository.save(new File(hash, hash, name, null));
 
-        int days = expiryDays != null ? Math.min(expiryDays, maxExpiryDays) : maxExpiryDays;
-        Integer limit = downloadLimit != null ? Math.min(downloadLimit, maxDownloadLimit) : null;
-
-        File f = new File(hash, hash, name, LocalDateTime.now().plusDays(days));
-        f.setDownloadLimit(limit);
-        fileRepository.save(f);
-
-        model.addAttribute("id", hash);
-        return "upload/result :: view";
+        return ResponseEntity.ok(Map.of("id", hash));
     }
 }

Backend/src/main/resources/static/crypto.js

@@ -1,28 +0,0 @@
-async function encryptFile(arrayBuffer) {
-    const key = await crypto.subtle.generateKey(
-        { name: 'AES-GCM', length: 256 },
-        true,
-        ['encrypt', 'decrypt']
-    );
-
-    const iv = crypto.getRandomValues(new Uint8Array(12));
-
-    const ciphertext = await crypto.subtle.encrypt({ name: 'AES-GCM', iv }, key, arrayBuffer);
-
-    // Payload: 12-byte IV prepended to ciphertext
-    const payload = new Uint8Array(12 + ciphertext.byteLength);
-    payload.set(iv, 0);
-    payload.set(new Uint8Array(ciphertext), 12);
-
-    // SHA-256(rawKey) → file identifier sent to server; server never sees the key itself
-    const rawKey = await crypto.subtle.exportKey('raw', key);
-    const hash = Array.from(new Uint8Array(await crypto.subtle.digest('SHA-256', rawKey)))
-        .map(b => b.toString(16).padStart(2, '0'))
-        .join('');
-
-    // Base64url-encode key for URL fragment
-    const base64urlKey = btoa(String.fromCharCode(...new Uint8Array(rawKey)))
-        .replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
-
-    return { payload, hash, base64urlKey };
-}

Backend/src/main/resources/static/upload.js

@@ -1,17 +1,28 @@
 const dropZone = document.getElementById('drop-zone');
 const fileInput = document.getElementById('file-input');
-const promptHtml = dropZone.innerHTML;
+
+const views = {
+    prompt:    document.getElementById('view-prompt'),
+    selected:  document.getElementById('view-selected'),
+    uploading: document.getElementById('view-uploading'),
+    result:    document.getElementById('view-result'),
+};
 
 let selectedFile = null;
 
+function showView(name) {
+    Object.entries(views).forEach(([key, el]) => el.classList.toggle('d-none', key !== name));
+}
+
 // ── File selection ────────────────────────────────────────────────────────────
 
 dropZone.addEventListener('click', () => {
-    if (selectedFile === null) fileInput.click();
+    if (views.prompt.classList.contains('d-none')) return;
+    fileInput.click();
 });
 
 fileInput.addEventListener('change', e => {
-    if (e.target.files[0]) onFileSelected(e.target.files[0]);
+    if (e.target.files[0]) selectFile(e.target.files[0]);
 });
 
 dropZone.addEventListener('dragover', e => {
@@ -24,78 +35,101 @@ dropZone.addEventListener('dragleave', () => dropZone.classList.remove('dragover
 dropZone.addEventListener('drop', e => {
     e.preventDefault();
     dropZone.classList.remove('dragover');
-    if (e.dataTransfer.files[0] && selectedFile === null) onFileSelected(e.dataTransfer.files[0]);
+    if (e.dataTransfer.files[0]) selectFile(e.dataTransfer.files[0]);
 });
 
-function onFileSelected(file) {
+function selectFile(file) {
     selectedFile = file;
-    // Use htmx to fetch the options form — server renders max values from config
-    htmx.ajax('GET', '/upload/options?name=' + encodeURIComponent(file.name), {
-        target: '#drop-zone',
-        swap: 'innerHTML'
-    });
+    document.getElementById('selected-name').textContent = file.name;
+    showView('selected');
 }
 
-// ── Upload (called from onclick in server-rendered options form) ──────────────
+document.getElementById('reset-btn').addEventListener('click', e => {
+    e.stopPropagation();
+    selectedFile = null;
+    fileInput.value = '';
+    showView('prompt');
+});
 
-async function startUpload() {
-    const expiryDays = document.getElementById('expiry-days')?.value;
-    const downloadLimit = document.getElementById('download-limit')?.value;
+document.getElementById('new-upload-btn').addEventListener('click', e => {
+    e.stopPropagation();
+    selectedFile = null;
+    fileInput.value = '';
+    showView('prompt');
+});
 
-    dropZone.innerHTML = `
-        <div class="mb-3">
-            <div class="spinner-border text-success" role="status">
-                <span class="visually-hidden">Loading\u2026</span>
-            </div>
-        </div>
-        <div class="drop-zone-text" id="upload-status">Encrypting\u2026</div>`;
+// ── Upload ────────────────────────────────────────────────────────────────────
+
+document.getElementById('upload-btn').addEventListener('click', async e => {
+    e.stopPropagation();
+    await upload();
+});
+
+function setStatus(msg) {
+    document.getElementById('upload-status').textContent = msg;
+}
+
+async function upload() {
+    const file = selectedFile;
+    showView('uploading');
 
     try {
-        const { payload, hash, base64urlKey } = await encryptFile(await selectedFile.arrayBuffer());
+        setStatus('Generating encryption key\u2026');
+        const key = await crypto.subtle.generateKey(
+            { name: 'AES-GCM', length: 256 },
+            true,
+            ['encrypt', 'decrypt']
+        );
+
+        const iv = crypto.getRandomValues(new Uint8Array(12));
+
+        setStatus('Encrypting\u2026');
+        const ciphertext = await crypto.subtle.encrypt(
+            { name: 'AES-GCM', iv },
+            key,
+            await file.arrayBuffer()
+        );
+
+        // Payload: 12-byte IV prepended to ciphertext
+        const payload = new Uint8Array(12 + ciphertext.byteLength);
+        payload.set(iv, 0);
+        payload.set(new Uint8Array(ciphertext), 12);
+
+        // SHA-256(rawKey) → file identifier sent to server (server never sees the key)
+        const rawKey = await crypto.subtle.exportKey('raw', key);
+        const hash = Array.from(new Uint8Array(await crypto.subtle.digest('SHA-256', rawKey)))
+            .map(b => b.toString(16).padStart(2, '0'))
+            .join('');
+
+        // Base64url-encode key for URL fragment
+        const base64urlKey = btoa(String.fromCharCode(...new Uint8Array(rawKey)))
+            .replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
 
         setStatus('Uploading\u2026');
-
         const formData = new FormData();
-        formData.append('file', new Blob([payload]), selectedFile.name);
+        formData.append('file', new Blob([payload]), file.name);
         formData.append('hash', hash);
-        formData.append('name', selectedFile.name);
-        if (expiryDays)    formData.append('expiryDays', expiryDays);
-        if (downloadLimit) formData.append('downloadLimit', downloadLimit);
+        formData.append('name', file.name);
 
         const response = await fetch('/upload', { method: 'POST', body: formData });
-        if (!response.ok) throw new Error(`Server error ${response.status}`);
+        if (!response.ok) throw new Error(`Server responded with ${response.status}`);
 
-        // Server returns HTML fragment; append key fragment client-side
-        dropZone.innerHTML = await response.text();
-        htmx.process(dropZone);
-        document.getElementById('share-link').value += '#' + base64urlKey;
+        const { id } = await response.json();
+        document.getElementById('share-link').value =
+            `${window.location.origin}/download/${id}#${base64urlKey}`;
+        showView('result');
 
     } catch (err) {
-        dropZone.innerHTML = `
-            <div class="drop-zone-icon mb-3">&#x26A0;</div>
-            <div class="drop-zone-text mb-3">${err.message}</div>
-            <button class="btn btn-link drop-zone-text text-decoration-none" onclick="resetUpload()">Try again</button>`;
+        setStatus(`Error: ${err.message}`);
     }
 }
 
-function setStatus(msg) {
-    const el = document.getElementById('upload-status');
-    if (el) el.textContent = msg;
-}
+// ── Copy link ─────────────────────────────────────────────────────────────────
 
-// ── Reset (called from onclick in server-rendered fragments) ──────────────────
-
-function resetUpload() {
-    selectedFile = null;
-    fileInput.value = '';
-    dropZone.innerHTML = promptHtml;
-}
-
-// ── Copy link (called from onclick in result fragment) ────────────────────────
-
-async function copyLink() {
+document.getElementById('copy-btn').addEventListener('click', async e => {
+    e.stopPropagation();
     await navigator.clipboard.writeText(document.getElementById('share-link').value);
     const btn = document.getElementById('copy-btn');
     btn.textContent = 'Copied!';
     setTimeout(() => { btn.textContent = 'Copy'; }, 2000);
-}
+});

Backend/src/main/resources/templates/index.html

@@ -8,7 +8,6 @@
     <link rel="stylesheet" th:href="@{/style.css}">
     <script th:src="@{/webjars/bootstrap/dist/js/bootstrap.bundle.min.js}" defer></script>
     <script th:src="@{/webjars/htmx.org/dist/htmx.min.js}" defer></script>
-    <script th:src="@{/crypto.js}" defer></script>
     <script th:src="@{/upload.js}" defer></script>
 </head>
 <body class="d-flex flex-column min-vh-100">
@@ -28,14 +27,52 @@
                 </p>
             </div>
             <div class="col-lg-7 d-flex justify-content-center justify-content-lg-end">
-                <input type="file" id="file-input" hidden>
                 <div id="drop-zone" class="drop-zone text-center py-5 px-4 w-100">
-                    <div class="drop-zone-icon mb-3">&#x1F4C2;</div>
-                    <div class="mb-2">
-                        <strong>Choose a file</strong>
-                        <span class="drop-zone-text"> or drag and drop here</span>
+
+                    <!-- State: prompt (default) -->
+                    <div id="view-prompt">
+                        <div class="drop-zone-icon mb-3">&#x1F4C2;</div>
+                        <div class="mb-2">
+                            <strong>Choose a file</strong>
+                            <span class="drop-zone-text"> or drag and drop here</span>
+                        </div>
+                        <div class="drop-zone-text small">Any file type &middot; Up to <span th:text="${maxFileSize}">10GB</span></div>
                     </div>
-                    <div class="drop-zone-text small">Any file type &middot; Up to <span th:text="${maxFileSize}">10GB</span></div>
+
+                    <!-- State: file selected -->
+                    <div id="view-selected" class="d-none">
+                        <div class="drop-zone-icon mb-3">&#x1F4C4;</div>
+                        <div class="fw-medium mb-3" id="selected-name"></div>
+                        <div class="d-flex gap-2 justify-content-center">
+                            <button id="upload-btn" class="btn btn-success px-4">Send</button>
+                            <button id="reset-btn" class="btn btn-link drop-zone-text text-decoration-none">Change file</button>
+                        </div>
+                    </div>
+
+                    <!-- State: uploading -->
+                    <div id="view-uploading" class="d-none">
+                        <div class="mb-3">
+                            <div class="spinner-border text-success" role="status">
+                                <span class="visually-hidden">Loading...</span>
+                            </div>
+                        </div>
+                        <div class="drop-zone-text" id="upload-status">Preparing&hellip;</div>
+                    </div>
+
+                    <!-- State: result -->
+                    <div id="view-result" class="d-none">
+                        <div class="drop-zone-icon mb-3">&#x2705;</div>
+                        <div class="drop-zone-text mb-3">Your file is ready to share</div>
+                        <div class="input-group mb-2">
+                            <input type="text" id="share-link" class="form-control form-control-sm" readonly>
+                            <button id="copy-btn" class="btn btn-outline-success btn-sm">Copy</button>
+                        </div>
+                        <button id="new-upload-btn" class="btn btn-link drop-zone-text text-decoration-none small">
+                            Send another file
+                        </button>
+                    </div>
+
+                    <input type="file" id="file-input" hidden>
                 </div>
             </div>
         </div>

Backend/src/main/resources/templates/upload/options.html

@@ -1,27 +0,0 @@
-<!DOCTYPE html>
-<html xmlns:th="http://www.thymeleaf.org">
-<body>
-<div th:fragment="form">
-    <div class="drop-zone-icon mb-3">&#x1F4C4;</div>
-    <div class="fw-medium mb-3 text-truncate" th:text="${name}">filename</div>
-
-    <div class="row g-2 mb-3 text-start">
-        <div class="col-6">
-            <label for="expiry-days" class="form-label drop-zone-text small">Expires after (days)</label>
-            <input type="number" id="expiry-days" class="form-control form-control-sm"
-                   min="1" th:max="${maxExpiryDays}" th:value="${maxExpiryDays}">
-        </div>
-        <div class="col-6">
-            <label for="download-limit" class="form-label drop-zone-text small">Download limit</label>
-            <input type="number" id="download-limit" class="form-control form-control-sm"
-                   min="1" th:max="${maxDownloadLimit}" placeholder="Unlimited">
-        </div>
-    </div>
-
-    <div class="d-flex gap-2 justify-content-center">
-        <button class="btn btn-success px-4" onclick="startUpload()">Send</button>
-        <button class="btn btn-link drop-zone-text text-decoration-none" onclick="resetUpload()">Change file</button>
-    </div>
-</div>
-</body>
-</html>

Backend/src/main/resources/templates/upload/result.html

@@ -1,17 +0,0 @@
-<!DOCTYPE html>
-<html xmlns:th="http://www.thymeleaf.org">
-<body>
-<div th:fragment="view">
-    <div class="drop-zone-icon mb-3">&#x2705;</div>
-    <div class="drop-zone-text mb-3">Your file is ready to share</div>
-    <div class="input-group mb-2">
-        <input type="text" id="share-link" class="form-control form-control-sm"
-               th:value="@{/download/{id}(id=${id})}" readonly>
-        <button id="copy-btn" class="btn btn-outline-success btn-sm" onclick="copyLink()">Copy</button>
-    </div>
-    <button class="btn btn-link drop-zone-text text-decoration-none small" onclick="resetUpload()">
-        Send another file
-    </button>
-</div>
-</body>
-</html>

LICENSE

@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.