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.
Setting encryption permissions for R >= 3 set permission bits in
groups corresponding to menu options in Acrobat 5. The new API allows
the bits to be set individually.
For non-encrypted files, determinstic ID generation uses file contents
instead of timestamp and file name. At a small runtime cost, this
enables generation of the same /ID if the same inputs are converted in
the same way multiple times.
Put a specific comment marker next to every piece of code that MSVC
gives warning 4996 for. This warning is generated for calls to
functions that Microsoft considers insecure or deprecated. This
change is in preparation for fixing all these cases even though none
of them are actually incorrect or insecure as used in qpdf. The
comment marker makes them easier to find so they can be fixed in
subsequent commits.
- Add a way to set the minimum PDF version
- Add a way to force the PDF version
- Have isEncrypted return true if an /Encrypt dictionary exists even
when we can't read the file
- Allow qpdf_init_write to be called multiple times
- Update some comments in headers
git-svn-id: svn+q:///qpdf/trunk@748 71b93d88-0707-0410-a8cf-f5a4172ac649
