Expose underlying error message for invalid input #1505

docs/changelog.md

@@ -17,6 +17,9 @@ Requires libvips v8.7.0.
 * Expose `pages` and `pageHeight` metadata for multi-page input images.
   [#1205](https://github.com/lovell/sharp/issues/1205)
 
+* Expose underlying error message for invalid input.
+  [#1505](https://github.com/lovell/sharp/issues/1505)
+
 * Prevent mutatation of options passed to `jpeg`.
   [#1516](https://github.com/lovell/sharp/issues/1516)
 

package.json

@@ -112,7 +112,7 @@
     "documentation": "^9.1.1",
     "exif-reader": "^1.0.2",
     "icc": "^1.0.0",
-    "license-checker": "^24.1.0",
+    "license-checker": "^25.0.1",
     "mocha": "^5.2.0",
     "mock-fs": "^4.7.0",
     "nyc": "^13.1.0",

src/common.cc

@@ -245,8 +245,8 @@ namespace sharp {
             if (imageType == ImageType::SVG || imageType == ImageType::PDF || imageType == ImageType::MAGICK) {
               SetDensity(image, descriptor->density);
             }
-          } catch (...) {
+          } catch (vips::VError const &err) {
-            throw vips::VError("Input buffer has corrupt header");
+            throw vips::VError(std::string("Input buffer has corrupt header: ") + err.what());
           }
         } else {
           throw vips::VError("Input buffer contains unsupported image format");
@@ -287,8 +287,8 @@ namespace sharp {
             if (imageType == ImageType::SVG || imageType == ImageType::PDF || imageType == ImageType::MAGICK) {
               SetDensity(image, descriptor->density);
             }
-          } catch (...) {
+          } catch (vips::VError const &err) {
-            throw vips::VError("Input file has corrupt header");
+            throw vips::VError(std::string("Input file has corrupt header: ") + err.what());
           }
         } else {
           throw vips::VError("Input file is missing or of an unsupported image format");

test/fixtures/index.js

@@ -70,6 +70,7 @@ module.exports = {
   inputJpgCenteredImage: getPath('centered_image.jpeg'),
   inputJpgRandom: getPath('random.jpg'), // convert -size 200x200 xc:   +noise Random   random.jpg
   inputJpgThRandom: getPath('thRandom.jpg'), // convert random.jpg  -channel G -threshold 5% -separate +channel -negate thRandom.jpg
+  inputJpgLossless: getPath('testimgl.jpg'), // Lossless JPEG from ftp://ftp.fu-berlin.de/unix/X11/graphics/ImageMagick/delegates/ljpeg-6b.tar.gz
 
   inputPng: getPath('50020484-00001.png'), // http://c.searspartsdirect.com/lis_png/PLDM/50020484-00001.png
   inputPngWithTransparency: getPath('blackbug.png'), // public domain

test/unit/metadata.js

@@ -457,6 +457,7 @@ describe('Image metadata', function () {
     sharp(fixtures.inputJpgWithCorruptHeader)
       .metadata(function (err) {
         assert.strictEqual(true, !!err);
+        assert.strictEqual(true, /Input file has corrupt header: VipsJpeg: Premature end of JPEG file/.test(err.message));
         done();
       });
   });
@@ -465,6 +466,16 @@ describe('Image metadata', function () {
     sharp(fs.readFileSync(fixtures.inputJpgWithCorruptHeader))
       .metadata(function (err) {
         assert.strictEqual(true, !!err);
+        assert.strictEqual(true, /Input buffer has corrupt header: VipsJpeg: Premature end of JPEG file/.test(err.message));
+        done();
+      });
+  });
+
+  it('Unsupported lossless JPEG passes underlying error message', function (done) {
+    sharp(fixtures.inputJpgLossless)
+      .metadata(function (err) {
+        assert.strictEqual(true, !!err);
+        assert.strictEqual(true, /Input file has corrupt header: VipsJpeg: Unsupported JPEG process: SOF type 0xc3/.test(err.message));
         done();
       });
   });