From b7ca8aceb4fae1330ef3e06230d0df44e27e3939 Mon Sep 17 00:00:00 2001
From: krlosMata <krlosmata@gmail.com>
Date: Fri, 28 Feb 2020 08:28:36 +0100
Subject: [PATCH] section size 8 bytes

---
 doc/r1cs_bin_format.md | 24 ++++++++++++------------
 src/r1csfile.js        | 38 ++++++++++++++++++++++++++++----------
 2 files changed, 40 insertions(+), 22 deletions(-)

diff --git a/doc/r1cs_bin_format.md b/doc/r1cs_bin_format.md
index fbe3ab0..1fd1593 100644
--- a/doc/r1cs_bin_format.md
+++ b/doc/r1cs_bin_format.md
@@ -507,9 +507,9 @@ The format will be:
      ┣━━━━━━━━━━━━━━┫
      ┃ 03 00 00 00  ┃       nSections
      ┗━━━━━━━━━━━━━━┛
-     ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━┓
-     ┃ 01 00 00 00  ┃ 49 00 00 00 ┃      SectionType: Header
-     ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━┛
+     ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━━━━┓
+     ┃ 01 00 00 00  ┃ 49 00 00 00 00 00 00 00  ┃      SectionType: Header
+     ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━━━━┛
         ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━┓
         ┃ 25 00 00 00  ┃ 10 00 00 00 ┃  FieldDefSize FieldDef
         ┣━━━━━━━━━━━━━━┻━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
@@ -531,9 +531,9 @@ The format will be:
         ┣━━━━━━━━━━━━━━┫
         ┃ 03 00 00 00  ┃    # Constraints
         ┗━━━━━━━━━━━━━━┛
-     ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━┓
-     ┃ 02 00 00 00  ┃ 8b 00 00 00 ┃      SectionType: Constraints
-     ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━┛
+     ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━━━┓
+     ┃ 02 00 00 00  ┃ 8b 00 00 00 00 00 00 00 ┃      SectionType: Constraints
+     ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━━━┛
         ┏━━━━━━━━━━━━━━┓   Constraint 0: (3w_5 + 8w_6) * (2w_0 + 20w_2 + 12w_3) - (5w_0 + 7w_2) = 0
         ┃ 02 00 00 00  ┃
         ┣━━━━━━━━━━━━━━╋━━━━━━━━┓
@@ -598,9 +598,9 @@ The format will be:
         ┃ 06 00 00 00  ┃  02 58 02   ┃
         ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━┛
 
-     ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━┓
-     ┃ 03 00 00 00  ┃ 1c 00 00 00 ┃      Wire to Label Map
-     ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━┛
+     ┏━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━━━┓
+     ┃ 03 00 00 00  ┃ 1c 00 00 00 00 00 00 00 ┃      Wire to Label Map
+     ┗━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━━━┛
         ┏━━━━━━━━━━━━━━┓
         ┃ 00 00 00 00  ┃
         ┣━━━━━━━━━━━━━━┫
@@ -624,7 +624,7 @@ And the binary representation in Hex:
 72 31 63 77
 01 00 00 00
 03 00 00 00
-01 00 00 00  49 00 00 00
+01 00 00 00  49 00 00 00 00 00 00 00
 25 00 00 00  10 00 00 00
 20 010000f0 93f5e143 9170b979 48e83328 5d588181 b64550b8 29a031e1 724e6430
 00 00 00 00
@@ -635,7 +635,7 @@ And the binary representation in Hex:
 03 00 00 00
 e8 03 00 00
 03 00 00 00
-02 00 00 00  8b 00 00 00
+02 00 00 00  8b 00 00 00 00 00 00 00
 02 00 00 00
 05 00 00 00  01 03
 06 00 00 00  01 08
@@ -662,7 +662,7 @@ e8 03 00 00
 03 00 00 00  01 05
 01 00 00 00
 06 00 00 00  02 58 02
-03 00 00 00  1c 00 00 00
+03 00 00 00  1c 00 00 00 00 00 00 00
 00 00 00 00
 03 00 00 00
 0a 00 00 00
diff --git a/src/r1csfile.js b/src/r1csfile.js
index b81d620..aae65af 100644
--- a/src/r1csfile.js
+++ b/src/r1csfile.js
@@ -31,7 +31,7 @@ async function loadR1cs(fileName, loadConstraints, loadMap) {
     let mapSize;
     for (let i=0; i<nSections; i++) {
         let ht = await readU32();
-        let hl = await readU32();
+        let hl = await readDouble64();
         if (ht == 1) {
             if (typeof pHeader != "undefined") assert(false, "File has two headder sections");
             pHeader = p;
@@ -114,6 +114,15 @@ async function loadR1cs(fileName, loadConstraints, loadMap) {
         return b.readInt32LE(0);
     }
 
+    async function readDouble64() {
+        const b = Buffer.allocUnsafe(8);
+        await fd.read(b, 0, 8, p);
+
+        p+=8;
+
+        return b.readDoubleLE(0);
+    }
+
     async function readBigInt() {
         const bl = Buffer.allocUnsafe(1);
         await fd.read(bl, 0, 1, p);
@@ -171,7 +180,7 @@ async function buildR1cs(ctx, fileName) {
     ///////////
     await writeU32(1); // Header type
     const pHeaderSize = p;
-    await writeU32(0); // Temporally set to 0 length
+    await writeDouble64(0); // Temporally set to 0 length
 
 
     // Field Def
@@ -198,13 +207,13 @@ async function buildR1cs(ctx, fileName) {
     await writeU32(ctx.signals.length);
     await writeU32(ctx.constraints.length);
 
-    const headerSize = p - pHeaderSize - 4;
+    const headerSize = p - pHeaderSize - 8;
 
     // Write constraints
     ///////////
     await writeU32(2); // Constraints type
     const pConstraintsSize = p;
-    await writeU32(0); // Temporally set to 0 length
+    await writeDouble64(0); // Temporally set to 0 length
 
     for (let i=0; i<ctx.constraints.length; i++) {
         if ((ctx.verbose)&&(i%10000 == 0)) {
@@ -214,13 +223,13 @@ async function buildR1cs(ctx, fileName) {
         await writeConstraint(ctx.constraints[i]);
     }
 
-    const constraintsSize = p - pConstraintsSize - 4;
+    const constraintsSize = p - pConstraintsSize - 8;
 
     // Write map
     ///////////
     await writeU32(3); // wires2label type
     const pMapSize = p;
-    await writeU32(0); // Temporally set to 0 length
+    await writeDouble64(0); // Temporally set to 0 length
 
 
     const arr = new Array(NWires);
@@ -238,13 +247,13 @@ async function buildR1cs(ctx, fileName) {
         if ((ctx.verbose)&&(i%100000)) console.log("writing label2wire map: ", i);
     }
 
-    const mapSize = p - pMapSize -4;
+    const mapSize = p - pMapSize - 8;
 
     // Write sizes
-    await writeU32(headerSize, pHeaderSize);
+    await writeDouble64(headerSize, pHeaderSize);
     await writeU32(fieldDefSize, pFieldDefSize);
-    await writeU32(constraintsSize, pConstraintsSize);
-    await writeU32(mapSize, pMapSize);
+    await writeDouble64(constraintsSize, pConstraintsSize);
+    await writeDouble64(mapSize, pMapSize);
 
     await fd.sync();
     await fd.close();
@@ -258,6 +267,15 @@ async function buildR1cs(ctx, fileName) {
         if (typeof(pos) == "undefined") p += 4;
     }
 
+    async function writeDouble64(v, pos) {
+        const b = Buffer.allocUnsafe(8);
+        b.writeDoubleLE(v);
+
+        await fd.write(b, 0, 8, pos);
+
+        if (typeof(pos) == "undefined") p += 8;
+    }
+
     async function writeConstraint(c) {
         await writeLC(c.a);
         await writeLC(c.b);