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| author | Denis Vlasenko <vda.linux@googlemail.com> | 2008-06-29 02:25:53 +0000 |
|---|---|---|
| committer | Denis Vlasenko <vda.linux@googlemail.com> | 2008-06-29 02:25:53 +0000 |
| commit | ce13b7600277478055de0b7c38b483a76145efd2 (patch) | |
| tree | b952e4328f8e182099fb3d72afc5c8978a56ebff /shell | |
| parent | 540ab7097c2932e8ef9e3bbb6abf5604c05acdde (diff) | |
| download | busybox-ce13b7600277478055de0b7c38b483a76145efd2.tar.gz | |
libbb: shrink monotonic_XXX functions, introduce monotonic_ns
(unused for now)
function old new delta
get_mono - 31 +31
sv_main 1228 1234 +6
expand 1693 1697 +4
get_address 178 181 +3
utoa_to_buf 108 110 +2
builtin_exit 46 48 +2
qrealloc 36 33 -3
qgravechar 109 106 -3
ash_main 1383 1380 -3
grep_file 850 846 -4
popstring 140 134 -6
monotonic_us 85 60 -25
monotonic_sec 41 16 -25
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 5/7 up/down: 48/-69) Total: -21 bytes
Diffstat (limited to 'shell')
| -rw-r--r-- | shell/ash.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/shell/ash.c b/shell/ash.c index 9c3216243..85064d5af 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -9615,7 +9615,6 @@ setcmd(int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED) } #if ENABLE_ASH_RANDOM_SUPPORT -/* Roughly copied from bash.. */ static void change_random(const char *value) { @@ -9636,10 +9635,11 @@ change_random(const char *value) if (random_galois_LFSR < 0) /* if we just shifted 1 out of msb... */ t ^= MASK; random_galois_LFSR = t; - /* Both are weak, xoring them gives better randomness + /* Both are weak, combining them gives better randomness * and ~2^64 period. & 0x7fff is probably bash compat - * for $RANDOM range. */ - t = (t ^ random_LCG) & 0x7fff; + * for $RANDOM range. Combining with subtraction is + * just for fun. + and ^ would work equally well. */ + t = (t - random_LCG) & 0x7fff; /* set without recursion */ setvar(vrandom.text, utoa(t), VNOFUNC); vrandom.flags &= ~VNOFUNC; @@ -13432,7 +13432,9 @@ int ash_main(int argc ATTRIBUTE_UNUSED, char **argv) rootpid = getpid(); #if ENABLE_ASH_RANDOM_SUPPORT - random_galois_LFSR = random_LCG = rootpid + time(NULL); + /* Can use monotonic_ns() for better randomness but for now it is + * not used anywhere else in busybox... so avoid bloat */ + random_galois_LFSR = random_LCG = rootpid + monotonic_us(); #endif init(); setstackmark(&smark); |