XFA - Add support for overflow element

- and fix few bugs:
    - avoid infinite loop when layout the document;
    - avoid confusion between break and layout failure;
    - don't add margin width in tb layout when getting available space.

src/core/xfa/layout.js

@@ -146,12 +146,9 @@ function addHTML(node, html, bbox) {
 
 function getAvailableSpace(node) {
   const availableSpace = node[$extra].availableSpace;
-  const [marginW, marginH] = node.margin
+  const marginH = node.margin
-    ? [
+    ? node.margin.topInset + node.margin.bottomInset
-        node.margin.leftInset + node.margin.rightInset,
+    : 0;
-        node.margin.topInset + node.margin.leftInset,
-      ]
-    : [0, 0];
 
   switch (node.layout) {
     case "lr-tb":
@@ -159,36 +156,49 @@ function getAvailableSpace(node) {
       switch (node[$extra].attempt) {
         case 0:
           return {
-            width: availableSpace.width - marginW - node[$extra].currentWidth,
+            width: availableSpace.width - node[$extra].currentWidth,
             height: availableSpace.height - marginH - node[$extra].prevHeight,
           };
         case 1:
           return {
-            width: availableSpace.width - marginW,
+            width: availableSpace.width,
             height: availableSpace.height - marginH - node[$extra].height,
           };
         default:
+          // Overflow must stay in the container.
           return {
             width: Infinity,
-            height: availableSpace.height - marginH - node[$extra].prevHeight,
+            height: Infinity,
           };
       }
     case "rl-row":
     case "row":
+      if (node[$extra].attempt === 0) {
         const width = node[$extra].columnWidths
           .slice(node[$extra].currentColumn)
           .reduce((a, x) => a + x);
         return { width, height: availableSpace.height - marginH };
+      }
+      // Overflow must stay in the container.
+      return { width: Infinity, height: Infinity };
     case "table":
     case "tb":
+      if (node[$extra].attempt === 0) {
         return {
-        width: availableSpace.width - marginW,
+          width: availableSpace.width,
           height: availableSpace.height - marginH - node[$extra].height,
         };
+      }
+      // Overflow must stay in the container.
+      return { width: Infinity, height: Infinity };
     case "position":
     default:
+      if (node[$extra].attempt === 0) {
         return availableSpace;
       }
+      // Overflow must stay in the container.
+      return { width: Infinity, height: Infinity };
+  }
 }
 
 export { addHTML, flushHTML, getAvailableSpace };

src/core/xfa/template.js

@@ -17,7 +17,6 @@ import {
   $acceptWhitespace,
   $addHTML,
   $appendChild,
-  $break,
   $childrenToHTML,
   $content,
   $extra,
@@ -91,6 +90,12 @@ const SVG_NS = "http://www.w3.org/2000/svg";
 // to handle the situation.
 const MAX_ATTEMPTS_FOR_LRTB_LAYOUT = 2;
 
+// It's possible to have a bug in the layout and so as
+// a consequence we could loop for ever in Template::toHTML()
+// so in order to avoid that (and avoid a OOM crash) we break
+// the loop after having MAX_EMPTY_PAGES empty pages.
+const MAX_EMPTY_PAGES = 3;
+
 function _setValue(templateNode, value) {
   if (!templateNode.value) {
     const nodeValue = new Value({});
@@ -194,26 +199,19 @@ const NOTHING = 0;
 const NOSPACE = 1;
 const VALID = 2;
 function checkDimensions(node, space) {
+  if (node[$getParent]().layout === "position") {
+    return VALID;
+  }
   const [x, y, w, h] = getTransformedBBox(node);
   if (node.w === 0 || node.h === 0) {
     return VALID;
   }
 
   if (node.w !== "" && Math.round(x + w - space.width) > 1) {
-    const area = getRoot(node)[$extra].currentContentArea;
-    if (x + w > area.w) {
-      return NOTHING;
-    }
-
     return NOSPACE;
   }
 
   if (node.h !== "" && Math.round(y + h - space.height) > 1) {
-    const area = getRoot(node)[$extra].currentContentArea;
-    if (y + h > area.h) {
-      return NOTHING;
-    }
-
     return NOSPACE;
   }
 
@@ -393,8 +391,7 @@ class Area extends XFAObject {
       availableSpace,
     };
 
-    if (
+    const result = this[$childrenToHTML]({
-      !this[$childrenToHTML]({
       filter: new Set([
         "area",
         "draw",
@@ -404,13 +401,16 @@ class Area extends XFAObject {
         "subformSet",
       ]),
       include: true,
-      })
+    });
-    ) {
+
+    if (!result.success) {
+      if (result.isBreak()) {
+        return result;
+      }
       // Nothing to propose for the element which doesn't fit the
       // available space.
       delete this[$extra];
-      // TODO: return failure or not ?
+      return HTMLResult.FAILURE;
-      return HTMLResult.empty;
     }
 
     style.width = measureToString(this[$extra].width);
@@ -2121,22 +2121,28 @@ class ExclGroup extends XFAObject {
         this[$extra].attempt < MAX_ATTEMPTS_FOR_LRTB_LAYOUT;
         this[$extra].attempt++
       ) {
-        if (
+        const result = this[$childrenToHTML]({
-          this[$childrenToHTML]({
           filter,
           include: true,
-          })
+        });
-        ) {
+        if (result.success) {
           break;
         }
+        if (result.isBreak()) {
+          return result;
+        }
       }
 
       failure = this[$extra].attempt === 2;
     } else {
-      failure = !this[$childrenToHTML]({
+      const result = this[$childrenToHTML]({
         filter,
         include: true,
       });
+      failure = !result.success;
+      if (failure && result.isBreak()) {
+        return result;
+      }
     }
 
     if (failure) {
@@ -4131,12 +4137,6 @@ class Subform extends XFAObject {
   }
 
   [$toHTML](availableSpace) {
-    if (this[$extra] && this[$extra].afterBreakAfter) {
-      const ret = this[$extra].afterBreakAfter;
-      delete this[$extra];
-      return ret;
-    }
-
     if (this.presence === "hidden" || this.presence === "inactive") {
       return HTMLResult.EMPTY;
     }
@@ -4152,6 +4152,21 @@ class Subform extends XFAObject {
       );
     }
 
+    if (this.breakBefore.children.length >= 1) {
+      const breakBefore = this.breakBefore.children[0];
+      if (!breakBefore[$extra]) {
+        // Set $extra to true to consume it.
+        breakBefore[$extra] = true;
+        return HTMLResult.breakNode(breakBefore);
+      }
+    }
+
+    if (this[$extra] && this[$extra].afterBreakAfter) {
+      const result = this[$extra].afterBreakAfter;
+      delete this[$extra];
+      return result;
+    }
+
     // TODO: incomplete.
     fixDimensions(this);
     const children = [];
@@ -4174,15 +4189,6 @@ class Subform extends XFAObject {
       currentWidth: 0,
     });
 
-    if (this.breakBefore.children.length >= 1) {
-      const breakBefore = this.breakBefore.children[0];
-      if (!breakBefore[$extra]) {
-        breakBefore[$extra] = true;
-        getRoot(this)[$break](breakBefore);
-        return HTMLResult.FAILURE;
-      }
-    }
-
     switch (checkDimensions(this, availableSpace)) {
       case NOTHING:
         return HTMLResult.EMPTY;
@@ -4192,6 +4198,14 @@ class Subform extends XFAObject {
         break;
     }
 
+    let noBreakOnOverflow = false;
+    if (this.overflow && this.overflow.target) {
+      const root = getRoot(this);
+      const target = root[$searchNode](this.overflow.target, this);
+      noBreakOnOverflow =
+        target && target[0] === root[$extra].currentContentArea;
+    }
+
     const filter = new Set([
       "area",
       "draw",
@@ -4232,32 +4246,32 @@ class Subform extends XFAObject {
       attributes.xfaName = this.name;
     }
 
-    let failure;
+    // If the container overflows into itself we add an extra
-    if (this.layout === "lr-tb" || this.layout === "rl-tb") {
+    // layout step to accept finally the element which caused
-      for (
+    // the overflow.
-        ;
+    let maxRun =
-        this[$extra].attempt < MAX_ATTEMPTS_FOR_LRTB_LAYOUT;
+      this.layout === "lr-tb" || this.layout === "rl-tb"
-        this[$extra].attempt++
+        ? MAX_ATTEMPTS_FOR_LRTB_LAYOUT
-      ) {
+        : 1;
-        if (
+    maxRun += noBreakOnOverflow ? 1 : 0;
-          this[$childrenToHTML]({
+    for (; this[$extra].attempt < maxRun; this[$extra].attempt++) {
-            filter,
+      const result = this[$childrenToHTML]({
-            include: true,
-          })
-        ) {
-          break;
-        }
-      }
-
-      failure = this[$extra].attempt === 2;
-    } else {
-      failure = !this[$childrenToHTML]({
         filter,
         include: true,
       });
+      if (result.success) {
+        break;
+      }
+      if (result.isBreak()) {
+        return result;
+      }
+    }
+
+    if (this[$extra].attempt === maxRun) {
+      if (this.overflow) {
+        getRoot(this)[$extra].overflowNode = this.overflow;
       }
 
-    if (failure) {
       if (this.layout === "position") {
         delete this[$extra];
       }
@@ -4294,19 +4308,17 @@ class Subform extends XFAObject {
       bbox = [this.x, this.y, width, height];
     }
 
+    const result = HTMLResult.success(createWrapper(this, html), bbox);
+
     if (this.breakAfter.children.length >= 1) {
       const breakAfter = this.breakAfter.children[0];
-      getRoot(this)[$break](breakAfter);
+      this[$extra].afterBreakAfter = result;
-      this[$extra].afterBreakAfter = HTMLResult.success(
+      return HTMLResult.breakNode(breakAfter);
-        createWrapper(this, html),
-        bbox
-      );
-      return HTMLResult.FAILURE;
     }
 
     delete this[$extra];
 
-    return HTMLResult.success(createWrapper(this, html), bbox);
+    return result;
   }
 }
 
@@ -4456,10 +4468,6 @@ class Template extends XFAObject {
     }
   }
 
-  [$break](node) {
-    this[$extra].breakingNode = node;
-  }
-
   [$searchNode](expr, container) {
     if (expr.startsWith("#")) {
       // This is an id.
@@ -4477,7 +4485,7 @@ class Template extends XFAObject {
     }
 
     this[$extra] = {
-      breakingNode: null,
+      overflowNode: null,
       pageNumber: 1,
       pagePosition: "first",
       oddOrEven: "odd",
@@ -4540,8 +4548,20 @@ class Template extends XFAObject {
     let targetPageArea;
     let leader = null;
     let trailer = null;
+    let hasSomething = true;
+    let hasSomethingCounter = 0;
 
     while (true) {
+      if (!hasSomething) {
+        // Nothing has been added in the previous page
+        if (++hasSomethingCounter === MAX_EMPTY_PAGES) {
+          warn("XFA - Something goes wrong: please file a bug.");
+          return mainHtml;
+        }
+      } else {
+        hasSomethingCounter = 0;
+      }
+
       targetPageArea = null;
       const page = pageArea[$toHTML]().html;
       mainHtml.children.push(page);
@@ -4560,6 +4580,17 @@ class Template extends XFAObject {
       const htmlContentAreas = page.children.filter(node =>
         node.attributes.class.includes("xfaContentarea")
       );
+
+      hasSomething = false;
+
+      const flush = index => {
+        const html = root[$flushHTML]();
+        if (html) {
+          hasSomething = true;
+          htmlContentAreas[index].children.push(html);
+        }
+      };
+
       for (let i = 0, ii = contentAreas.length; i < ii; i++) {
         const contentArea = (this[$extra].currentContentArea = contentAreas[i]);
         const space = { width: contentArea.w, height: contentArea.h };
@@ -4574,7 +4605,7 @@ class Template extends XFAObject {
           trailer = null;
         }
 
-        let html = root[$toHTML](space);
+        const html = root[$toHTML](space);
         if (html.success) {
           if (html.html) {
             htmlContentAreas[i].children.push(html.html);
@@ -4582,17 +4613,11 @@ class Template extends XFAObject {
           return mainHtml;
         }
 
-        // Check for breakBefore / breakAfter
+        if (html.isBreak()) {
-        let mustBreak = false;
+          const node = html.breakNode;
-        if (this[$extra].breakingNode) {
-          const node = this[$extra].breakingNode;
-          this[$extra].breakingNode = null;
 
           if (node.targetType === "auto") {
-            html = root[$flushHTML]();
+            flush(i);
-            if (html) {
-              htmlContentAreas[i].children.push(html);
-            }
             continue;
           }
 
@@ -4616,34 +4641,68 @@ class Template extends XFAObject {
 
           if (node.targetType === "pageArea") {
             if (startNew) {
-              mustBreak = true;
+              flush(i);
+              i = Infinity;
             } else if (target === pageArea || !(target instanceof PageArea)) {
               // Just ignore the break and do layout again.
               i--;
-              continue;
             } else {
               // We must stop the contentAreas filling and go to the next page.
               targetPageArea = target;
-              mustBreak = true;
+              flush(i);
+              i = Infinity;
             }
-          } else if (
+          } else if (node.targetType === "contentArea") {
-            target === "contentArea" ||
+            const index = contentAreas.findIndex(e => e === target);
-            !(target instanceof ContentArea)
+            if (index !== -1) {
-          ) {
+              flush(i);
-            // Just ignore the break and do layout again.
+              i = index - 1;
+            } else {
               i--;
+            }
+          }
           continue;
         }
+
+        if (this[$extra].overflowNode) {
+          const node = this[$extra].overflowNode;
+          this[$extra].overflowNode = null;
+
+          flush(i);
+
+          if (node.leader) {
+            leader = this[$searchNode](node.leader, node[$getParent]());
+            leader = leader ? leader[0] : null;
           }
 
-        html = root[$flushHTML]();
+          if (node.trailer) {
-        if (html) {
+            trailer = this[$searchNode](node.trailer, node[$getParent]());
-          htmlContentAreas[i].children.push(html);
+            trailer = trailer ? trailer[0] : null;
           }
 
-        if (mustBreak) {
+          let target = null;
-          break;
+          if (node.target) {
+            target = this[$searchNode](node.target, node[$getParent]());
+            target = target ? target[0] : target;
           }
+
+          if (target instanceof PageArea) {
+            // We must stop the contentAreas filling and go to the next page.
+            targetPageArea = target;
+            i = Infinity;
+            continue;
+          } else if (target instanceof ContentArea) {
+            const index = contentAreas.findIndex(e => e === target);
+            if (index !== -1) {
+              i = index - 1;
+            } else {
+              i--;
+            }
+          }
+          continue;
+        }
+
+        flush(i);
       }
 
       this[$extra].pageNumber += 1;

src/core/xfa/utils.js

@@ -168,21 +168,30 @@ function getBBox(data) {
 
 class HTMLResult {
   static get FAILURE() {
-    return shadow(this, "FAILURE", new HTMLResult(false, null, null));
+    return shadow(this, "FAILURE", new HTMLResult(false, null, null, null));
   }
 
   static get EMPTY() {
-    return shadow(this, "EMPTY", new HTMLResult(true, null, null));
+    return shadow(this, "EMPTY", new HTMLResult(true, null, null, null));
   }
 
-  constructor(success, html, bbox) {
+  constructor(success, html, bbox, breakNode) {
     this.success = success;
     this.html = html;
     this.bbox = bbox;
+    this.breakNode = breakNode;
+  }
+
+  isBreak() {
+    return !!this.breakNode;
+  }
+
+  static breakNode(node) {
+    return new HTMLResult(false, null, null, node);
   }
 
   static success(html, bbox = null) {
-    return new HTMLResult(true, html, bbox);
+    return new HTMLResult(true, html, bbox, null);
   }
 }
 

src/core/xfa/xfa_object.js

@@ -23,7 +23,6 @@ import { searchNode } from "./som.js";
 const $acceptWhitespace = Symbol();
 const $addHTML = Symbol();
 const $appendChild = Symbol();
-const $break = Symbol();
 const $childrenToHTML = Symbol();
 const $clean = Symbol();
 const $cleanup = Symbol();
@@ -342,7 +341,7 @@ class XFAObject {
       const availableSpace = this[$getAvailableSpace]();
       const res = this[$extra].failingNode[$toHTML](availableSpace);
       if (!res.success) {
-        return false;
+        return res;
       }
       if (res.html) {
         this[$addHTML](res.html, res.bbox);
@@ -357,7 +356,7 @@ class XFAObject {
       }
       const res = gen.value;
       if (!res.success) {
-        return false;
+        return res;
       }
       if (res.html) {
         this[$addHTML](res.html, res.bbox);
@@ -366,7 +365,7 @@ class XFAObject {
 
     this[$extra].generator = null;
 
-    return true;
+    return HTMLResult.EMPTY;
   }
 
   [$setSetAttributes](attributes) {
@@ -960,7 +959,6 @@ export {
   $acceptWhitespace,
   $addHTML,
   $appendChild,
-  $break,
   $childrenToHTML,
   $clean,
   $cleanup,

test/pdfs/xfa_annual_expense_report.pdf.link

@@ -0,0 +1 @@
+https://web.archive.org/web/20210509141350/https://www.sos.state.oh.us/globalassets/elections/directives/2020/dir2020-25_annualexpensereport.pdf

test/pdfs/xfa_annual_voting_survey.pdf.link

@@ -0,0 +1 @@
+https://web.archive.org/web/20210509141345/https://www.sos.state.oh.us/globalassets/elections/directives/2020/dir2020-25_eavsform.pdf

test/pdfs/xfa_bug1716047.pdf.link

@@ -0,0 +1 @@
+https://bugzilla.mozilla.org/attachment.cgi?id=9226577

test/test_manifest.json

@@ -930,6 +930,30 @@
        "link": true,
        "type": "load"
     },
+    {  "id": "xfa_bug1716047",
+       "file": "pdfs/xfa_bug1716047.pdf",
+       "md5": "2f524163bd8397f43d195090978c3b56",
+       "link": true,
+       "rounds": 1,
+       "enableXfa": true,
+       "type": "eq"
+    },
+    {  "id": "xfa_annual_expense_report",
+       "file": "pdfs/xfa_annual_expense_report.pdf",
+       "md5": "06866e7a6bbc0346789208ef5f6e885c",
+       "link": true,
+       "rounds": 1,
+       "enableXfa": true,
+       "type": "eq"
+    },
+    {  "id": "xfa_annual_voting_survey",
+       "file": "pdfs/xfa_annual_voting_survey.pdf",
+       "md5": "92239648ea1bf189435c927e498c4ec9",
+       "link": true,
+       "rounds": 1,
+       "enableXfa": true,
+       "type": "eq"
+    },
     {  "id": "xfa_fish_licence",
        "file": "pdfs/xfa_fish_licence.pdf",
        "md5": "9b993128bbd7f4217098fd44116ebec2",