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use std
use sys
/* plan 9 can't have directory loops, by construction, so this is nops */
pkg fileutil =
type loopcheck = std.htab((int64, int64), void)#
const mkloopcheck : (cwd : byte[:] -> loopcheck)
const freeloopcheck : (l : loopcheck -> void)
const looped : (l : loopcheck, p : byte[:] -> bool)
;;
const mkloopcheck = {cwd
var ht : std.htab((int64, int64), void)#
var l
ht = std.mkht(fidhash, fideq)
l = (ht : loopcheck)
looped(l, cwd)
-> l
}
const freeloopcheck = {l
std.htfree((l : std.htab((int64, int64), void)#))
}
const looped = {l, p
var ht, has
ht = (l : std.htab((int64, int64), void)#)
match fid(p)
| `std.Err e:
-> false
| `std.Ok id:
has = std.hthas(ht, id)
std.htput(ht, id, void)
-> has
;;
}
const fid = {p
var sb
if sys.stat(p, &sb) != 0
-> `std.Err void
else
-> `std.Ok ((sb.dev : int64), (sb.ino : int64))
;;
}
const fidhash = {fid
var dev, ino
(dev, ino) = fid
-> std.inthash(dev) ^ std.inthash(ino)
}
const fideq = {a, b
var adev, aino
var bdev, bino
(adev, aino) = a
(bdev, bino) = b
-> adev == bdev && aino == bino
}
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