osmo_loadXXbe_ext -- was: [PATCH 1/8] libcommon: soak up three static functions.
+uint64_t decode_big_endian(const uint8_t *data, size_t data_len) +uint8_t *encode_big_endian(uint64_t value, size_t data_len) have you looked at osmo_load64le_ext of libosmocore? I think you don't need these routines. and it applies to GSUP too.
Ah, nice. Hadn't seen those yet. Oh well, I notice that the decode_big_endian() is more elegant to use than osmo_load64be_ext(), since passing a length of less than 8 bytes to decode_big_endian() writes the N least significant bytes, and allows this: uint16_t val; val = decode_big_endian(buf, sizeof(val)); It has the desired result. However this: uint16_t val; val = osmo_load64be_ext(buf, sizeof(val)); will write the bytes bound to the "wrong", most significant end of the uint64_t, and only zero is written to val. So I would need to explicitly use osmo_load16be(). Which is less elegant, isn't it? Is it about performance? Would changing that behavior break anything besides bitrev_test.c? (It checks for exactly this ordering) I'd like to change only the osmo_loadXXbe_ext() function, so that it writes the least significant bytes, like decode_big_endian() does. But first, does it write the most significant end for a reason? If it doesn't, we don't actually need to generate functions for each integer size. Instead we can glorify the decode_big_endian() and encode_big_endian(), made threadsafe, to become osmo_load/store*(). Right?? Except for bitrev_test.c, all callers I found (in my currently cloned few source trees) use only the non-"_ext" functions, and would not be affected by the change at all. ~Neels P.S.: Holger, after I said to you that osmo_loadXXbe_ext is not less elegant after all, I re-re-realized that it is indeed still less elegant...
bump ... any opinions on changing osmo_load*_ext() so that it always writes the least significant end instead of (currently) the most significant one? Details below... It would technically require a major version bump, but are there likely any callers relying on current behavior? It would not make much sense anyway (maybe a partial read, but I see no way to resume such read). Thanks, ~Neels On Fri, Oct 09, 2015 at 01:44:54AM +0200, Neels Hofmeyr wrote:
+uint64_t decode_big_endian(const uint8_t *data, size_t data_len) +uint8_t *encode_big_endian(uint64_t value, size_t data_len) have you looked at osmo_load64le_ext of libosmocore? I think you don't need these routines. and it applies to GSUP too.
Ah, nice. Hadn't seen those yet.
Oh well, I notice that the decode_big_endian() is more elegant to use than osmo_load64be_ext(), since passing a length of less than 8 bytes to decode_big_endian() writes the N least significant bytes, and allows this:
uint16_t val; val = decode_big_endian(buf, sizeof(val));
It has the desired result. However this:
uint16_t val; val = osmo_load64be_ext(buf, sizeof(val));
will write the bytes bound to the "wrong", most significant end of the uint64_t, and only zero is written to val. So I would need to explicitly use osmo_load16be().
Which is less elegant, isn't it? Is it about performance? Would changing that behavior break anything besides bitrev_test.c? (It checks for exactly this ordering)
I'd like to change only the osmo_loadXXbe_ext() function, so that it writes the least significant bytes, like decode_big_endian() does. But first, does it write the most significant end for a reason?
If it doesn't, we don't actually need to generate functions for each integer size. Instead we can glorify the decode_big_endian() and encode_big_endian(), made threadsafe, to become osmo_load/store*().
Right??
Except for bitrev_test.c, all callers I found (in my currently cloned few source trees) use only the non-"_ext" functions, and would not be affected by the change at all.
~Neels
P.S.: Holger, after I said to you that osmo_loadXXbe_ext is not less elegant after all, I re-re-realized that it is indeed still less elegant...
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Neels Hofmeyr