Previous interfaces for these libcurl internal functions did not allow to tell
apart a legitimate zero size result from an error condition. These functions
now return a CURLcode indicating function success or otherwise specific error.
Output size is returned using a pointer argument.

All usage of these two functions, and others closely related, has been adapted
to the new interfaces. Relative error and OOM handling adapted or added where
missing. Unit test 1302 also adapted.

With "@unittest: [num]" in the header comment for each tested function.
Shows we have a log way to go still...

Fix compiler warning: expression has no effect

Fix OOM handling

By the use of a the new lib/checksrc.pl script that checks that our
basic source style rules are followed.

Massively reduce #ifdefs all over (23 #ifdef lines less so far)
Moved conversion-specific code to non-ascii.c

convert Curl_ultous() and Curl_ultouc() functions to curlx_ultous() and
curlx_ultouc(), exposing them through curlx.h to allow proper code reuse
later in our test harness.

add header inclusion

fix compiler warning

fix compiler warning

fix compiler warning

fix compiler warning

fix compiler warning

We do testing of code functions using the test suite instead!

consistency

and allow reuse by multiple protocols. Several unused error codes were
removed.  In all cases, macros were added to preserve source (and binary)
compatibility with the old names.  These macros are subject to removal at
a future date, but probably not before 2009.  An application can be
tested to see if it is using any obsolete code by compiling it with the
CURL_NO_OLDIES macro defined.

Documented some newer error codes in libcurl-error(3)

  non-ASCII platforms.

could very well cause a negate number get passed in and thus cause reading
outside of the array usually used for this purpose.

We avoid this by using the uppercase macro versions introduced just now that
does some extra crazy typecasts to avoid byte codes > 127 to cause negative
int values.

precaution to prevent mistakes to lead to buffer overflows.

memory.h is included everywhere for this.