Fail if blob start plus length overflows; or if blob length
is greater than 2GB. It takes a while for fonts to get to that
size. In the mean time, it protects against bugs like this:
http://www.icu-project.org/trac/ticket/11450
Also avoids some weird issues with 32bit vs 64bit systems
as we accept length as unsigned int. As such, a length of
-1 will cause overflow on 32bit machines, but happily
accepted on a 64bit machine. Avoid that.
After 763e5466c0, one doesn't
need to set flags for different pieces of text. The flags now
are something the client sets up once, depending on how it
actually uses the buffer. As such, don't clear it in
clear_contents().
Tests updated.
With this change, we now by default replace broken UTF-8/16/32 bits
with U+FFFD. This can be changed by calling new API on the buffer.
Previously the replacement value used to be (hb_codepoint_t)-1.
Note that hb_buffer_clear_contents() does NOT reset the replacement
character.
See discussion here:
6f13b6d62d
New API:
hb_buffer_set_replacement_codepoint()
hb_buffer_get_replacement_codepoint()
HB_VERSION_CHECK's comparison was originally written wrongly
by mistake. When API tests were written, they were also written
wrongly to pass given the wrong implementation... Sigh.
Given the purpose of this API, there's no point in fixing it
without renaming it. As such, rename.
API changes:
HB_VERSION_CHECK -> HB_VERSION_ATLEAST
hb_version_check -> hb_version_atleast
New API:
hb_buffer_flags_t
HB_BUFFER_FLAGS_DEFAULT
HB_BUFFER_FLAG_BOT
HB_BUFFER_FLAG_EOT
HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES
hb_buffer_set_flags()
hb_buffer_get_flags()
We use the BOT flag to decide whether to insert dottedcircle if the
first char in the buffer is a combining mark.
The PRESERVE_DEFAULT_IGNORABLES flag prevents removal of characters like
ZWNJ/ZWJ/...
Behdad Esfahbod
Luis de Bethencourt