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| author | Frank Ch. Eigler <fche@elastic.org> | 2009-09-23 16:41:40 -0400 |
|---|---|---|
| committer | Frank Ch. Eigler <fche@elastic.org> | 2009-09-23 16:41:40 -0400 |
| commit | d098276239dd9f2e1ad031b48519a5a21779c369 (patch) | |
| tree | 9b288ad5fcf9ac9b7a13f3bdc986621230d60dc2 /tapset | |
| parent | 09846ceb72c27dfe87f0b5c8d0a6296fc09bbc36 (diff) | |
| download | systemtap-steved-d098276239dd9f2e1ad031b48519a5a21779c369.tar.gz systemtap-steved-d098276239dd9f2e1ad031b48519a5a21779c369.tar.xz systemtap-steved-d098276239dd9f2e1ad031b48519a5a21779c369.zip | |
PR10632: simplify randint() implementation
* tapset/random.stp (randint): Make it 1-arity (imply min=0).
Document with kerneldoc.
* doc/Systemtap_Tapset_Reference/tapsets.tmpl: Extract the docs.
* runtime/arith.c (_stp_random_pm_u): Rename without _pm.
(_stp_random_pm): Rewrite in terms of ..._u.
* testsuite/random.stp: Adapt & simplify.
Diffstat (limited to 'tapset')
| -rw-r--r-- | tapset/random.stp | 28 |
1 files changed, 12 insertions, 16 deletions
diff --git a/tapset/random.stp b/tapset/random.stp index e0a89d19..ada94216 100644 --- a/tapset/random.stp +++ b/tapset/random.stp @@ -1,18 +1,14 @@ -/** @addtogroup library -* The library tapset is a collection of standard functions. -* @{ -*/ - -function randint:long(min:long, max:long) +/** + * sfunction randint - Return a random number between [0,n) + * @n: Number past upper limit of range, not larger than 2**20. + */ +function randint:long(n:long) %{ - - unsigned long difference = (unsigned long)(THIS->max - THIS->min); - - if ( THIS->min >= THIS->max || (THIS->max -THIS->min) > (1024*1024) ){ - CONTEXT->last_error = "either first argument was not strictly less than the second argument, or their difference was greater than (1024*1024)"; - } - THIS->__retvalue = THIS->min + ( _stp_random_pm_u(2147483646) % (difference + 1) ); - +#define RANDMAX (1024*1024) + if (THIS->n > RANDMAX) + CONTEXT->last_error = "range too wide"; + else { + THIS->__retvalue = (uint64_t) _stp_random_u((unsigned long) THIS->n); + } +#undef RANDMAX %} - -/** @} */ |