With rare exceptions ...
- Always separate line continuation characters by one space from
preceding code.
- Always use two-space indentation. Never use tabs.
- Always use K&R-style conditional blocks.
- Always surround operators with spaces, except in raw assembly code.
- Always put a space after, but not before, a comma.
- Never put a space between type casts and variables/function calls.
- Never put a space between the function name and the argument list in
function declarations and prototypes.
- Always surround braces ('{' and '}') with spaces.
- Always surround statements (if, for, else, catch, while, do, switch)
with spaces.
- Always attach pointer symbols ('*' and '**') to the variable or
function name.
- Always precede pointer symbols ('*' and '**') by a space in type
casts.
- Use the MIN() macro from jpegint.h within the libjpeg and TurboJPEG
API libraries (using min() from tjutil.h is still necessary for
TJBench.)
- Where it makes sense (particularly in the TurboJPEG code), put a blank
line after variable declaration blocks.
- Always separate statements in one-liners by two spaces.
The purpose of this was to ease maintenance on my part and also to make
it easier for contributors to figure out how to format patch
submissions. This was admittedly confusing (even to me sometimes) when
we had 3 or 4 different style conventions in the same source tree. The
new convention is more consistent with the formatting of other OSS code
bases.
This commit corrects deviations from the chosen formatting style in the
libjpeg API code and reformats the TurboJPEG API code such that it
conforms to the same standard.
NOTES:
- Although it is no longer necessary for the function name in function
declarations to begin in Column 1 (this was historically necessary
because of the ansi2knr utility, which allowed libjpeg to be built
with non-ANSI compilers), we retain that formatting for the libjpeg
code because it improves readability when using libjpeg's function
attribute macros (GLOBAL(), etc.)
- This reformatting project was accomplished with the help of AStyle and
Uncrustify, although neither was completely up to the task, and thus
a great deal of manual tweaking was required. Note to developers of
code formatting utilities: the libjpeg-turbo code base is an
excellent test bed, because AFAICT, it breaks every single one of the
utilities that are currently available.
- The legacy (MMX, SSE, 3DNow!) assembly code for i386 has been
formatted to match the SSE2 code (refer to
ff5685d5344273df321eb63a005eaae19d2496e3.) I hadn't intended to
bother with this, but the Loongson MMI implementation demonstrated
that there is still academic value to the MMX implementation, as an
algorithmic model for other 64-bit vector implementations. Thus, it
is desirable to improve its readability in the same manner as that of
the SSE2 implementation.
Previously, -stoponwarning only had an effect on the underlying
TurboJPEG C functions, but TJBench still aborted if a non-fatal error
occurred. This commit modifies the C version of TJBench such that it
always recovers from a non-fatal error unless -stoponwarning is
specified. Furthermore, the benchmark stores the details of the last
non-fatal error and does not print any subsequent non-fatal error
messages unless they differ from the last one.
Due to limitations in the Java API (specifically, the fact that it
cannot communicate errors, fatal or otherwise, to the calling program
without throwing a TJException), it was only possible to make
decompression operations fully recoverable within TJBench. With other
operations, -stoponwarning still has an effect on the underlying C
library but has no effect at the Java level.
The Java API documentation has been amended to reflect that only certain
methods are truly recoverable, regardless of the state of
TJ.FLAG_STOPONWARNING.
Use a new checked exception type (TJException) when passing through
errors from the underlying C library. This gives the application a
choice of catching all exceptions or just those from TurboJPEG.
Throw IllegalArgumentException at the JNI level when arguments to the
JNI function are incorrect, and when one of the TurboJPEG "utility"
functions returns an error (because, per the C API specification, those
functions will only return an error if one of their arguments is out of
range.)
Remove "throws Exception" from the signature of any methods that no
longer pass through an error from the TurboJPEG C library.
Credit Viktor for the new code
Code formatting tweaks
Change the behavior of the bailif0() macro in the JNI wrapper so that it doesn't throw an exception for an unexpected NULL condition. In fact, in all cases, the underlying JNI API function (such as GetFieldID(), etc.) will throw an Error on its own whenever it returns NULL, so our custom exceptions were never being thrown in that case anyhow. All we need to do is just detect the error and bail out of the C code.
This also corrects a couple of formatting issues (semicolons aren't needed at the end of class definitions, and @Override should be specified for the methods we're overriding from super-classes, so the compiler can sanity-check that we're actually overriding a method and not declaring a new one.)
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1595 632fc199-4ca6-4c93-a231-07263d6284db
