After opening a specific file or fd for ourselves, reset the
CAIRO_TRACE_FD to point to an invalid fd in order to prevent any child
processes (who inherit our environment) from attempting to trace cairo
calls. If we allow them to continue, then the two traces will intermix
and be unreplayable.
Embed the pixels for images less than 32*32 as this catches most icons
which are frequently uploaded, but is still an unlikely size for a
destination image surface.
Using a null surface is a convenient method to measure the overhead of the
performance testing framework, so export it although as a test-surface so
that it will only be available in development builds and not pollute
distributed libraries.
Need to allow user programs to dump their traces into the common output
directory, when using /etc/ld.so.preload to capture traces for the entire
desktop.
Carl spotted this last night, but I misinterpreted it as an old problem
caused by the application changing its working directory before its first
cairo call - thus causing cairo-trace to attempt to open a file in the new
directory. Instead the problem was attempting to trace an executable with
an absolute path, where we just tagged it with a .lzma extentsion and
attempted to pipe the output there. Obviously this fails for the user
profiling system binaries. So use basename to strip the leading path.
python lazily loads libcairo.so and so it is not available via RTLD_NEXT,
and we need to dlopen cairo ourselves. Similarly the linker is not able to
resolve any naked function references and so we need to ensure that all of
our own calls into the library are wrapped with DLCALL.
These can be reasonably large and persist for long times due to the
font holdover caches, so manually swap them out to save space on tiny
swapless machines.
As an aide to tiny swapless systems write the rarely used bytes that
define type42 fonts into a deleted file and mmap them back into our
address space.
csi_string_new() duplicated the bytes which was not what was desired, so
implement a csi_string_new_for_bytes() to take ownership and prevent the
leak that was occuring, for example, every time we create a new font face.
Seeing unexpected time inside pixman composite is quite disturbing when
trying to track down the apparent slowness in some benchmarks. Remove one
source of this artefact by simply memcpy'ing pixel data when trivial.
Objects like cairo_scaled_font_t may return a reference to a previously
defined scaled-font instead of creating a new token each time. This caused
cairo-trace to overflow its operand stack by pushing a new instance of the
old token every time. Modify the tracer such that a font token can only
appear once on the stack -- for font-faces we remove the old operand and
for scaled-fonts we simply pop, chosen to reflect expected usage.
Applications such as swfdec have a strictly correct use of mark-dirty and
so we need an option to re-enable mark-dirty tracing in conjunction with
--profile.
When using fonts circular references are established between the holdover
font caches and the interpreter which need manual intervention via
cairo_script_interpreter_finish() to break.
To save typing when creating macro-benchmarks --profile disables
mark-dirty and caller-info and compresses the trace using LZMA. Not for
computers short on memory!
The glyph advance cache was only enabled for glyph indices < 256,
causing a large number of misses for non-ASCII text. Improve this by
simply applying the modulus of the index to select the cache slot - which
may cause some glyph advances to be overwritten and re-queried, but
improves the hit rate.
Record the current working directory and pass that along to cairo-trace so
that the trace output is local to the user and not the application. This
is vital if the application is called via a script that changes directory.
Applications like firefox have a very conservative approach and mark
surfaces dirty before every render. As we record the image data every
time, firefox traces can grow very large with redundant data - so allow
the user to disable mark dirty tracing.
At Behdad's request, convert the array of allocators into a simple hash
table (large static number of buckets + chaining) in order to speed up
malloc profiling.
In order to have locale-independent output of decimal values, we need to
manually transform such numbers into strings. As this is a solved problem
for cairo, we adopt _cairo_output_stream_printf() and in particular the
_cairo_dtostr() routine for our own printf processing.
