These have been found using `gulp lint` in combination with the `unused:
true` parameter for JSHint. Unfortunately there are too many false
positives to enable this feature, but now that most globals have been
removed because of the conversion to UMD the results are much more
useful than before.
In the font in question, there are a couple of `topDict` entries that have invalid values (`0xF 0xF`, i.e. just eof markers without any actual numbers).
This causes the `parseFloatOperand` function, inside `CFFParser_parseDict`, to return `NaN`. Currently we pass this broken font onto the browser, which OTS unsurprisingly rejects.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1068432.
As evident from e.g. PRs 6485 and 7118, some bad PDF generators unfortunately create Arrays where *some* elements are indirect objects (i.e. `Ref`s). This seems to mostly affect Arrays that contain numbers, such as e.g. `Matrix/FontMatrix/BBox/FontBBox/Rect/Color/...`, and has manifested itself in PDF files that fail to render correctly (some elements are missing).
The problem in both the cases above, besides broken rendering, was that there were *no* errors/warnings that indicated what the problem was, making it difficult to pinpoint the issue.
Hence this patch, where I've audited all usages of `Dict_get` in `src/core/` files, and replaced it with `Dict_getArray` where appropriate to try and prevent unnecessary future bugs.
- Add support for the 'NewWindow' property.
- Ensure that destinations are applied to the *remote* document, instead of the current one.
- Handle the `F` entry being a standard string, instead of a dictionary.
Using `new {Name,Cmd}` should be avoided, since it creates a new object on *every* call, whereas `{Name,Cmd}.get` uses caches to only create *one* object regardless of how many times they are called.
Most of these are found in the unit-tests, where increased memory usage probably doesn't matter very much. But it still seems good to get rid of those cases, since no part of the codebase ought to advertise that usage.
Given the small size of the patch, I'm also tweaking a few comments and class names.
Note that in the PDF files provided by the reporter, this issue was limited to `Rect` arrays in AcroForm entries (which we currently don't support).
However, since a bad PDF generator could create this problem in *any* kind of annotation, the reduced test-case included here uses a simple LinkAnnotation instead.
Fixes 7115.
According to "The table directory" under https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6.html#Directory, TrueType font tables should have `uint32` checksums.
This is something that I noticed, and was initially confused about, while debugging a TrueType issue.
As far as I can tell, the current (`int32`) checksums we use doesn't cause any issues in practice. However, I do think that this should be addressed to agree with the specification, and to reduce possible confusion when reading the font code.
Currently there's a lot of duplicate code for non-embedded `toFontChar`, which this patch simplifies by extracting the code into a helper function instead.
This patch adds a `getUnicodeForGlyph` helper function, which is used to recover Unicode values for non-standard glyph names.
Some PDF generators, e.g. Scribus PDF, use improper `uniXXXX` glyph names which breaks the glyph mapping. We can avoid this by converting them to "standard" glyph names instead.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1132849.
Fixes 6893.
Fixes 6894.
In the PDF file in question, some of the 'name' table entries have `record.length === 0`. This becomes problematic in the non-unicode case, since `font.getBytes(0)` will fetch the *entire* stream.
Given that OTS rejects 'name' entries larger than `2^16`, this thus explain the sanitizer errors.
Fixes 7020.
*A more robust solution for issue 6066.*
As a temporary work-around for (the upstream) [bug 1164199](https://bugzilla.mozilla.org/show_bug.cgi?id=1164199), we parsed *all* images in the Firefox addon during a short time.
Doing so uncovered an issue with our image handling (see 6066), for JPEG images with a `DeviceGray` ColorSpace *and* `bpc !== 1` (bits per component).
As long as we let the browser handle image decoding in this case, this isn't going to be an issue, but I do think that we should proactively fix this to avoid future issues if we change where the images are decoded (in `jpg.js` vs in browser).
Also, we currently don't seem to have a test-case for that kind of image data.
Currently the `C` entry in an outline item is returned as is, which is neither particularly useful nor what the API documentation claims.
This patch also adds unit-tests for both the color handling, and the `F` entry (bold/italic flags).
`Dict_getAll` is problematic for a number of reasons. First of all, as issue 6961 shows, it can be really bad for performance, since it dereferences all indirect objects.
Second of all, all the derefencing can lead to data being unncessarily requested when ranged/chunked loading is used, thus unnecessarily delaying rendering.
Note: For cases where `Dict_getAll` was previously used, `Dict_getKeys` in combination with `Dict_get` can be used instead. This has the advantage that data isn't requested until it's actually needed.
For the operators that we currently support, the arguments are not `Dict`s, which means that it's not really necessary to use `Dict_getAll` in `EvaluatorPreprocessor_read`.
Also, I do think that if/when we support operators that use `Dict`s as arguments, that should be dealt with in the corresponding `case` in `PartialEvaluator_getOperatorList` which handles the operator.
The only reason that I can find for using `Dict_getAll` like that, is that prior to PR 6550 we would just append certain (currently unsupported) operators without doing any further processing/checking. But as issue 6549 showed, that can lead to issues in practice, which is why it was changed.
In an effort to prevent possible issue with unsupported operators, this patch simply ignores operators with `Dict` arguments in `PartialEvaluator_getOperatorList`.
For the `CalGray`/`CalRGB`/`Lab` colour spaces, we're currently using `getAll` to retrieve the parameters. However that's not really necessary, since we may just as well explicitly `get` the needed parameters instead.
Some bad PDF generators, in particular "Scribus PDF", duplicates resources *a lot* at various levels of the PDF files. This can lead to `PartialEvaluator_hasBlendModes` taking an unreasonable amount of time to complete.
The reason is that the current code is using `Dict_getAll`, which recursively dereferences *all* indirect objects, which can be really slow. This patch instead uses `Dict_getKeys`, and then manually looks up only the necessary indirect objects.
I've added the PDF file as a `load` test. The most important thing here is probably to ensure that the file remains available in the repo, and the comment should help reduced the chance of regressions. (Note that locally, the `load` test times out without this patch, but we cannot really assume that that always happens.)
Fixes 6961.
*This patch is based on something I noticed while debugging some of the PDF files in issue 6931.*
In a number of the cases in `setGState`, we're implicitly assuming that we're not dealing with indirect objects (i.e. `Ref`s). See e.g. the 'Font' case, or the various cases where we simply do `gStateObj.push([key, value]);` (since the code in `canvas.js` won't be able to deal with a `Ref` for those cases).
The reason that I didn't use `Dict_forEach` instead, is that it would re-introduce the unncessary closures that PR 5205 removed.
The intention of PR 5192 was to avoid adding empty `setGState` ops to the operatorList. But the patch accidentally used `>=`, which means that it's not actually working as intended, since empty arrays always have `length === 0`.
Even though the currently known test-cases render correctly without this patch, that seems more like a lucky coincidence, given that there's no guarantee that `transferMap[255] === 0` for every possible transfer function.
This patch fixes an issue that I inadvertently introduced in PR 5815, where we accidentally modify the `Differences` array in the encoding dictionary for indirect objects.
Instead of this change, we could also have used the now existing `Dict_getArray`. However in this case I don't think that would have been a good idea, since it would mean iterating through the array *twice*.
Re: issue 5089.
(Note that since there are other outline features that we currently don't support, e.g. bold/italic text and custom colours, I thus think we can keep the referenced issue open.)
It seems to be fairly common for OCR software to include incomplete TrueType fonts, notable missing the "glyf" table, in PDF files. Since we currently reject such fonts, the result is that text-selection/copying is broken.
This patch contains a suggested approach to try and use these kind of broken fonts, by using existing code in `sanitizeGlyphLocations` to replace a missing "glyf" table with dummy data.
Fixes 4684.
Fixes 6007.
Fixes 6829.
*This patch follows a similar idea as PR 5756.*
The patch is based on the nice debugging done by Brendan in the referenced issue 6782.
A better way to handle this, and similar issues, would probably be to completely ignore what the PDF file claims about font type/subtype, and just check the actual data. But until that kind of rewrite happens, this patch should help.
Fixes 6782.
Most code for Popup annotations is already present for Text annotations.
This patch extracts the popup creation logic from the Text annotation
code so it can be reused for Popup annotations.
Not only does this add support for Popup annotations, the Text
annotation code is also considerably easier. If a `Popup` entry is
available for a Text annotation, it will not be more than an image. The
popup will be handled by the Popup annotation. However, it is also
possible for Text annotations to not have a separate Popup annotation,
in which case the Text annotation handles the popup creation itself.
Now we have a full list of all possible annotation types and the
numbering corresponds to the order in the specification. Not only is
this more consistent and complete, it also prevents having to add these
constants when a new annotation type is implemented.
Additionally fix an issue where a regular Widget annotation would not
have `data.annotationType` set. It was only set for a
TextWidgetAnnotation, but instead move it to the base Widget annotation
class to add it for all Widget annotations (since TextWidgetAnnotation
inherits from WidgetAnnotation it will have it too).
In `Font_checkAndRepair` we can decide that a font isn't TrueType, and instead parse it as CFF. In that case it's quite possible that the `fontMatrix` will be changed, and without calling `adjustWidths` we're failing to update the glyph widths correctly.
Fixes 5027.
Fixes 5084.
Fixes 6556.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1204903.
After PR 6590, `font.spaceWidth` is now called in more cases than before (in `PartialEvaluator_getTextContent`), which exposed an underlying issue with `IdentityToUnicodeMap_charCodeOf` throwing an error.
This breaks text-selection in some PDF files found in the wild, hence this patch replaces the `error` with an actual function instead (modelled after `IdentityCMap_charCodeOf`).
This patch improves the code structure of the annotation code.
- Create the annotation border style object in the `setBorderStyle` method instead of in the constructor. The behavior is the same as the `setBorderStyle` method is always called, thus a border style object is still always available.
- Put all data object manipulation lines in one block in the constructor. This improves readability and maintainability as it is more visible which properties are exposed.
- Simplify `appendToOperatorList` by removing the promise capability and removing an unused parameter.
- Remove some unnecessary newlines/spaces.
*This is a regression from PR 3424.*
The PDF file in the referenced issue is using `Type3` fonts. In one of those, the `/CharProcs` dictionary contains an entry with the name `/#`. Before the changes to `Lexer_getName` in PR 3424, we were allowing certain invalid `Name` patterns containing the NUMBER SIGN (#).
It's unfortunate that this has been broken for close to two and a half years before the bug surfaced, but it should at least indicate that this is not a widespread issue.
Fixes 6692.
This patch goes a bit further than issue 6612 requires, and replaces all kinds of whitespace with standard spaces.
When testing this locally, it actually seemed to slightly improve two existing test-cases (`tracemonkey-text` and `taro-text`).
Fixes 6612.
Currently `getAnnotations` will *only* fetch annotations that are either `viewable` or `printable`. This is "hidden" inside the `core.js` file, meaning that API consumers might be confused as to why they are not recieving *all* the annotations present for a page.
I thus think that the API should, by default, return *all* available annotations unless specifically told otherwise. In e.g. the default viewer, we obviously only want to display annotations that are `viewable`, hence this patch adds an `intent` parameter to `getAnnotations` that makes it possible to decide if only `viewable` or `printable` annotations should be fetched.
This patch makes it possible to set and get all possible flags that the PDF specification defines. Even though we do not support all possible annotation types and not all possible annotation flags yet, this general framework makes it easy to access all flags for each annotation such that annotation type implementations can use this information.
We add constants for all possible annotation flags such that we do not need to hardcode the flags in the code anymore. The `isViewable()` and `isPrintable()` methods are now easier to read. Additionally, unit tests have been added to ensure correct behavior.
This is another part of #5218.
I received multiple reports about the following cryptic error in the
Chrome extension when the user tried to open a local file:
> PDF.js v1.1.527 (build: 2096a2a)
> Message: Cannot read property 'Symbol(Symbol.iterator)' of null
This error most likely originated from core/stream.js:
function Stream(arrayBuffer, start, length, dict) {
this.bytes = (arrayBuffer instanceof Uint8Array ?
arrayBuffer : new Uint8Array(arrayBuffer));
^^^^^^^^^^^
`arrayBuffer` is `null`, and that in turn is caused by the fact that
for non-existing files, there is no data. I've applied two fixes:
1. Never call onDone with a void buffer, but call the error handler
instead.
2. Show a sensible error message for local files with status = 0.
In the `RenderPageRequest` handler in `worker.js`, we attempt to print an `info` message containing the rendering time and the length of the operator list. The latter is currently broken (and has been for quite some time), since the `length` of an `OperatorList` is reset when flushing occurs.
This patch attempts to rectify this, by adding a getter which keeps track of the total length.
`operatorList.addOp` adds the arguments to the list which is then
passed as-is by postMessage to the main thread. But since we don't
parse these operations, they are raw PDF objects and may therefore
cause a serialization error.
This is a conservative patch, and only affects operators which are
known to be unsupported. We should ignore all unknown operators,
but I haven't really looked into the consequences of doing that.
Fixes#6549
In PR 6485 I somehow missed to account for the case where `xref` is undefined. Since a dictonary can be initialized without providing a reference to an `xref` instance, `Dict_getArray` can thus fail without this added check.
According to the PDF spec 5.3.2, a positive value means in horizontal,
that the next glyph is further to the left (so narrower), and in
vertical that it is further down (so wider).
This change fixes the way PDF.js has interpreted the value.
This patch adjusts `get fingerprint` to also check that the `/ID` entry contains (non-empty) strings, to prevent more possible failures when loading corrupt PDF files (follow-up to PR 5602).
Note that I've not actually encountered such a PDF file in the wild. However given that `stringToBytes` will assert that the input is a string, and that we'll thus fail to load a document unless `get fingerprint` succeeds, making this more robust seems like a good idea to me.
For (1, 0) cmaps, we have two different codepaths depending on whether the font has/hasn't got an encoding. But with (3, 1) cmaps we don't have a good fallback when the encoding is missing, hence this patch changes `readCmapTable` to only choose a (3, 1) cmap table if the font is non-symbolic *and* an encoding exists. Without this, we'll not be able to successfully create a working glyph map for some TrueType fonts with (3, 1) cmap tables.
Fixes 6410.
This code was added in PR 1214, but was made obsolete by PRs 1488/1493. Prior to the latter ones, `Dict_get` retured the raw objects. However, afterwards (and currently) `Dict_get` now resolves indirect objects, which makes `Parser_fetchIfRef` redundant.
*Potential risks with this patch:*
This patch passes all tests locally, but there's a *small* possibility that it could break some weird PDF files.
In the current code, wrapping `Dict_get` inside `Parser_fetchIfRef` will potentially mean two back-to-back call of `XRef_fetch`, if a reference points directly to another reference. I'm not sure if this can actually happen in practice, and I'd think that if that were the case we'd already have run into it elsewhere in the code-base, given that `Parser` is the only place where we try to "double" resolve references.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1200096.
The problematic font has a `format 2` cmap, which we've never supported properly. Prior to PR 2606, we were able to fallback to a working state, despite not having proper support for that cmap format.
Obviously the best/correct solution would be to implement actual support for more cmap formats[1]. However, I'm hoping that a simple patch will be OK for now, given that:
- `format 2` cmaps seem to be quite rare in practice, since this has been broken for 2.5 years before anyone noticed.
- Having a simple patch will make potential uplifts a lot easier.
[1] See the specification at https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6cmap.html
Having a warning here would have meant that issue 6360 could have been solved in approximately five minutes, instead of an hour. To avoid that happening again, this patch adds a warning whenever we treat a stream as empty.
This patch improves the detection of `xref` in files where it is followed by an arbitrary whitespace character (not just a line-breaking char).
It also adds a check for missing whitespace, e.g. `1 0 obj<<`, to speed up `readToken` for the PDF file in the referenced issue.
Finally, the patch also replaces a bunch of magic numbers with suitably named constants.
Fixes 5752.
Also improves 6243, but there are still issues.
The problem with the PDF files in the issue, besides the obviously broken XRef tables which we're able to recover from, is that many/most of the streams have Dictionaries where the `Length` entry is set to `0`. This causes us to return `NullStream`, instead of the appropriate one in `Parser_makeFilter`.
Fixes 6360.
In some cases, such as in use with a CSP header, constructing a function with a
string of javascript is not allowed. However, compiling the various commands
that need to be done on the canvas element is faster than interpreting them.
This patch changes the font renderer to instead emit commands that are compiled
by the font loader. If, during compilation, we receive an EvalError, we instead
interpret them.
CMaps may be sparse. Array.prototype.forEach is terribly slow in Chrome
(and also in Firefox) when the sparse array contains a key with a high
value. E.g.
console.time('forEach sparse')
var a = [];
a[0xFFFFFF] = 1;
a.forEach(function(){});
console.timeEnd('forEach sparse');
// Chrome: 2890ms
// Firefox: 1345ms
Switching to CMap.prototype.forEach, which is optimized for such
scenarios fixes the problem.
pi is an index in the stream and is explained on page 201 of the 32000-spec (however 1-based there), and ps is an index to something in PDF.js. I used the code from flag 0 (which works) to understand which is which. It is also important to understand that for flags 1,2 and 3, the stream is always assigned to the same coordinates and colors. What changes is which "old" coordinates and colors are assigned to what is "missing" in the stream. This is why for these flags, the code is identical except for the assignments in the first "row". (Same principle as in #6304). Note that this change will not improve the lamp_cairo.pdf file, only the two files mentioned in #6305.
Short story: somebody got lost in two different indices. pi is an index in the stream and is explained on page 198 of the 32000-spec (however 1-based there), and ps is an index to something in PDF.js. I used the code from flag 0 (which works) to understand which is which. It is also important to understand that for flags 1,2 and 3, the stream is always assigned to the same coordinates and colors. What changes is which "old" coordinates and colors are assigned to what is "missing" in the stream. This is why for these flags, the code is identical except for the assignments in the first "row".
Currently, `src/core/core.js` uses the `fromRef` method on an `Annotation` object to obtain the right annotation type object (such as `LinkAnnotation` or `TextAnnotation`). That method in turn uses a method `getConstructor` to find out which annotation type object must be returned.
Aside from the fact that there is currently a lot of code to achieve this, these methods should not be part of the base `Annotation` class at all. Creation of annotation object should be done by a factory (as also recommended by @yurydelendik at https://github.com/mozilla/pdf.js/pull/5218#issuecomment-52779659) that handles finding out the correct annotation type object and returning it. This patch implements this separation of concerns.
Doing this allows us to also simplify the code quite a bit and to make it more readable. Additionally, we are now able to get rid of the hardcoded array of supported annotation types. The factory takes care of checking the annotation types and falls back to returning the base annotation type (and issuing a warning, which the current code also does not do well) when an annotation type is unsupported.
I have manually tested this commit with 20 test PDFs with different annotation types, such as /Link, /Text, /Widget, /FileAttachment and /FreeText. All render identically before and after the patch, and unsupported annotation types are now properly indicated with a warning in the console.