This change applies some recommendations from jralls. It better utilizes for loops,
and usage of swap. We also try to make sure the null guid is not freed since it's
reused, and catch a c++ exception to make sure it doens't escape into C code when
parsing a GUID.
Previously, guid_to_string had been marked deprecated with a note about
it not being thread-safe. It was much worse than "not thread safe", it
was only safe in a particular situation, and its safety was being violated
throughout the code. It was clear that users of guid_to_string did not
understand what it was purporting to do because of its varied uses. Most
uses simply treated it like a Garbage-Collected Java String (use and forget).
I actually found at least one instance where the string was being freed. (!!!)
I made the method have a particular easy-to-understand semantic: it returns
a pointer to a string which must be freed by the caller. I then tried to
track down all uses of this function and correct them. Mostly, I just changed
the usage to guid_to_string_buff with a stack-allocated string to avoid the
the malloc/free cycle.
To allocate a GUID, use guid_malloc. To allocate and construct a guid
(which is actually unique), use guid_new (and be sure to free it using
guid_free).
`new` implies some allocation. Since guid_new was actually constructing
a guid in place rather than allocating it, it makes much more sense to
call it guid_replace (or guid_construct). We went with guid_replace.
Since we're maintaining a C api, the implementation is sometimes less than
intuitive from either a C or C++ perspective. I am trying to use as much
boost as possible while making all the guarantees that the C code makes.
One function was declared deprecated because it "wasn't thread safe". This
was straightforward to repair, and is no longer marked deprecated, and there
are now two ways to convert GUID to String: passing your own character
buffer, and having one returned to you that you need to free.
MinGW declares any standard functions not part of the ISO C standard
in #ifndef __STRICT_ANSI__ blocks; Gcc defines __STRICT_ANSI__ with
-std=c++11; Pass 'ext' to the C++11 macro to get -std=gnu++ll, which allows
all those extensions we use.
The plan is to change gnc guid to use boost's guid implementation. There were
no tests for guid before, but we need them to ensure that we don't have regressions
when that work begins.
gnc_sxed_check_consistent() was failing to balance mortgage payments with
large payments or small interest amounts because of rounding errors with
only 6 significant digits. Using 18 causes values < 1 to overflow, so I
compromised on 12.
Also log an error and return NULL if there's an overflow, since the value
won't be useful.
