They could make the returned structure a nesting structure in their structure. Better to make things more convenient for the typical case, not the unusual case.
On Tue, Jan 3, 2023 at 12:28 PM Masakazu Kitajo <mas...@apache.org> wrote: > What's the benefit of forcing users to use the structure? A user might want > to store the returned pointer into a user-defined structure. > > > > On Tue, Sep 6, 2022 at 10:24 AM Walt Karas <wka...@yahooinc.com.invalid> > wrote: > > > Presumably we don't need to allow for use of antiquated C compilers that > > don't allow structures as return values. So this: > > > > typedef struct > > { > > char *data; > > int length; > > } > > TSVarLenData; > > > > TSVarLenData TSSomething(x, y, z); > > > > Is another alternative. > > > > On Thu, Sep 1, 2022 at 5:32 PM Masakazu Kitajo <mas...@apache.org> > wrote: > > > > > Using encapsulation/data abstraction is fine, but it doesn't seem like > > > TSHeapBuf makes sense. No TS API receives it. If plugin code is the > only > > > user and it has to deal with a non-const raw pointer and a data length > > > after all, why do we want to wrap them in the first place? > > > > > > As for smaller steps, like I suggested on the PR, you could introduce > > > TSHeapBuf separately from the fix, I think. And if there are similar TS > > > APIs that could return TSHeapBuf, supporting TSHeapBuf on only one of > > them > > > makes inconsistency in TS API. IMO, the two changes, the fix and the > new > > > API, should be made like 1 + 1, but not 1.5 + 0.5 nor 1 + 0.5 + 0.5. > > > > > > Masakazu > > > > > > On Thu, Sep 1, 2022 at 10:08 AM Walt Karas <wka...@yahooinc.com.invalid > > > > > wrote: > > > > > > > As a rule of thumb, I prefer using encapsulation/data abstraction. I > > > think > > > > perhaps that is one reason I've been a poor match to this project. > > There > > > > doesn't seem to be a consensus that we should follow this rule of > > thumb. > > > > > > > > KIt, that would be my preference. But I am part of the consensus I > > think > > > > we have, that we should favor a series of smaller steps, rather than > > > doing > > > > all of them in one big step. > > > > > > > > On Wed, Aug 31, 2022 at 12:13 PM Shu Kit Chan <chanshu...@gmail.com> > > > > wrote: > > > > > > > > > Also are we planning to eventually rewrite our existing APIs (where > > > > > applicable) to use this? > > > > > > > > > > On Wed, Aug 31, 2022 at 8:36 AM Masakazu Kitajo <mas...@apache.org > > > > > > wrote: > > > > > > > > > > > > What's the advantage of using TSHeapBuf? What issue does it > solve? > > > > > > > > > > > > > > > > > > On Wed, Aug 31, 2022 at 7:48 AM Walt Karas > > > <wka...@yahooinc.com.invalid > > > > > > > > > > > wrote: > > > > > > > > > > > > > Described here: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://urldefense.com/v3/__https://github.com/apache/trafficserver/blob/os_pkey_cnf_reload/doc/developer-guide/api/functions/TSHeapBuf.en.rst*tsheapbufdata__;Iw!!Op6eflyXZCqGR5I!Du0fBfMhb4pdM2ECFijJ7aJ-jT70jEPeZwjhsvWt2Dr2cSZ5G7HWY20wZOmFHIR3MxnvPZpoRDMlII5dgow$ > > > > > > > > > > > > , > > > > > > > > > > > > > > In PR > > > > > > > > > > > > > > > https://urldefense.com/v3/__https://github.com/apache/trafficserver/pull/8790__;!!Op6eflyXZCqGR5I!Du0fBfMhb4pdM2ECFijJ7aJ-jT70jEPeZwjhsvWt2Dr2cSZ5G7HWY20wZOmFHIR3MxnvPZpoRDMlYh9lIuc$ > > > > > . > > > > > > > > > > > > > > This allows a dynamically allocated buffer, of any reasonable > > > length, > > > > > to be > > > > > > > returned by a TS API function, like this: > > > > > > > > > > > > > > TSHeapBuf hb = TSSomething(x, y, z); > > > > > > > > > > > > > > One alternative is an interface like this: > > > > > > > > > > > > > > int length; > > > > > > > char *data = TSSomething(x, y, z, &length); > > > > > > > > > > > > > > The data is dynamically allocated, and would be freed with > > > TSfree(). > > > > > > > > > > > > > > Another alternative is: > > > > > > > > > > > > > > char *buf = TSalloc(BUF_SIZE); > > > > > > > int actual_size = TSSomething(x, y, z, buf, BUF_SIZE); > > > > > > > if (actual_size > BUF_SIZE) { > > > > > > > // buf was too small, unchanged. > > > > > > > TSfree(buf); > > > > > > > buf = TSalloc(actual_size); > > > > > > > TSSomething(x, y, z, buf, actual_size); > > > > > > > } > > > > > > > > > > > > > > > > > > > > > >