This makes all integer type conversions that have potential data loss
explicit with calls that do range checks and raise an exception. After
this commit, qpdf builds with no warnings when -Wsign-conversion
-Wconversion is used with gcc or clang or when -W3 -Wd4800 is used
with MSVC. This significantly reduces the likelihood of potential
crashes from bogus integer values.
There are some parts of the code that take int when they should take
size_t or an offset. Such places would make qpdf not support files
with more than 2^31 of something that usually wouldn't be so large. In
the event that such a file shows up and is valid, at least qpdf would
raise an error in the right spot so the issue could be legitimately
addressed rather than failing in some weird way because of a silent
overflow condition.
Bounding box X coordinates could be truncated, causing them to be off
by a fraction of a point. This was most likely not visible, but it was
still wrong.
This is the set of files from the latest corpus of running the older
fuzzer (qpdf_read_memory_fuzzer) at the time of adding the new fuzzer
(qpdf_fuzzer) after running a merge operation to minimize the corpus.
On read, ignore /DecodeParms when empty list; on write, delete it.
Some files have been found that include an empty list for
/DecodeParms, but this is not technically compliant with the spec, and
the only sensible interpretation is to treat it as if there are no
decode parameters.
The preservation of outlines didn't provide very useful behavior
anyway as it copied all outlines but most didn't work. This
implementation also caused a very significant performance hit and so
is being reverted until a proper solution can be coded. The eventual
solution will not be compatible with the reverted solution anyway, so
it's best not to leave this in.
* [bcc32 Error] QPDF.cc(375): E2268 Call to undefined function 'atof'
Full parser context
QPDF.cc(358): parsing: void QPDF::parse(const char *)
* [bcc32 Error] QPDFTokenizer.cc(183): E2268 Call to undefined function 'strtol'
Full parser context
QPDFTokenizer.cc(163): parsing: void QPDFTokenizer::resolveLiteral()
* [bcc32 Error] pdf-split-pages.cc(52): E2268 Call to undefined function 'exit'
Full parser context
pdf-split-pages.cc(50): parsing: void usage()
* PR #295: Including "cstdlib" should be replaced with "stdlib.h" to be more consistent. At the same time I changed the order of the surrounding includes to reflect alphabetical order, because at some files this already have been the case.
Fix C++ exception handling when -fvisibility=hidden
Ensure that QPDFExc and QPDFSystemError are marked visible, so that their typeinfo will not be
suppressed when -fvisibility=hidden.
Details:
https://gcc.gnu.org/wiki/Visibility
Embarcadero C++Builder doesn't support more than 50 files open at the same time for legacy 32 Bit apps, which makes a test fail trying to open more than that many files. This changes the number of open files for that test to far less to make the test succeed. Alternatively one could reduce the hard coded number of 200 in QPDF itself, which I didn't do currently because it needs adoption of manuals etc. and is something which needs to be discussed with the author of QPDF. I guess chances are better to get the test changed upstream.
This fixes #288: https://github.com/qpdf/qpdf/issues/288