With older library logic having been modified to avoid
using those potentially deadly alloc.h routines, while
improving 'errno' handling, we're ready to standardize
and enhance newlib's approach to any potential errors.
In so doing, we'll establish the following objectives:
. . . . . . . . . . . . . functions returning an 'int'
. an error will be indicated by a negative number that
is always the inverse of some well known errno.h value
. . . . . . . . . . . functions returning an 'address'
. any error will be indicated by a NULL return pointer
with the actual reason found in the formal errno value
And, when errno is manipulated directly we will strive
to do so whenever possible within those routines which
have been declared with PROCPS_EXPORT. In other words,
in the user callable functions defined in source last.
[ But, that won't always be possible. In particular, ]
[ all the 'read_failed' functions will sometimes set ]
[ 'errno' so that they can serve callers returning a ]
[ NULL or an int without duplicating a lot of logic. ]
[ Also, that includes one subordinate function which ]
[ was called by 'read_failed' in the <slabinfo> API. ]
------------------------------------------------------
Along the way, several additional miscellaneous issues
were addressed. They're listed here now for posterity.
. the '-1' return value passed outside the library was
eliminated since it would erroneously equate to -EPERM
. the stacks_fetch functions in <diskstats> and <stat>
weren't checked for their possible minus return values
. hash create was not checked in <meminfo> or <vmstat>
. fixed 'new' function faulty parm check in <slabinfo>
Signed-off-by: Jim Warner <james.warner@comcast.net>
06be33b43e