1 #!/usr/local/plan9/bin/rc
2 
3 path=($path $PLAN9/bin)
4 
5 fn usage {
6 	echo 'usage: yesterday [-cd] [-[[yy]yy]mm]dd] [-n daysago] file ...' >[1=2]
7 	exit 1
8 }
9 
10 fn Xcp {
11 	echo cp $1 $2
12 	cp $1 $2
13 }
14 
15 fn Xcarefulcp {
16 	if(! cmp -s $1 $2) Xcp $1 $2
17 }
18 
19 fn Xdiff {
20 	echo diff -c $1 $2
21 	diff -c $1 $2
22 }
23 
24 fn Xecho {
25 	echo $1
26 }
27 
28 year=`{date|sed 's/.* //'}
29 copy=Xecho
30 last=()
31 while(! ~ $#* 0 && ~ $1 -* && ! ~ $1 --){
32 	switch($1){
33 	case -c
34 		copy=Xcp
35 		shift
36 	case -d
37 		copy=Xdiff
38 		shift
39 	case -C
40 		copy=Xcarefulcp
41 		shift
42 	case -n*
43 		if(~ $1 -n){
44 			if(~ $#* 1)
45 				usage
46 			shift
47 			days=$1
48 		}
49 		if not
50 			days=`{echo $1 | sed 's/^-.//'}
51 		last=`{date -r `{perl -e 'print time() - '$days'*60*60*24'} | 
52 				9 sed -e 's%... (...) (..) ..:..:.. ... (....)%\3/\1\2%' -e 'y/ /0/' -e $smon}
53 		shift
54 	case -[0-9]
55 		mon=`{date|9 sed 's/^....(...).*/\1/' -e $smon}
56 		last=$year/$mon ^`{echo $1|sed 's/^-/0/'}
57 		shift
58 	case -[0-9][0-9]
59 		mon=`{date|9 sed 's/^....(...).*/\1/' -e $smon}
60 		last=$year/$mon ^`{echo $1|9 sed 's/^-//'}
61 		shift
62 	case -[0-9][0-9][0-9][0-9]
63 		last=$year/ ^ `{echo $1|9 sed 's/^-//'}
64 		shift
65 	case -[0-9][0-9][0-9][0-9][0-9][0-9]
66 		last=`{echo $year|9 sed 's/..$//'} ^ `{echo $1|9 sed 's/^-(..)/\1\//'}
67 		shift
68 	case -[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]
69 		last=`{echo $1|9 sed 's/^-(....)/\1\//'}
70 		shift
71 	case *
72 		usage
73 	}
74 }
75 if(! ~ $#* 0 && ~ $1 --)
76 	shift
77 
78 if(~ $#* 0)
79 	usage
80 
81 dir=`{pwd}
82 if(! ~ $status ''){
83 	echo 'yesterday: can''t find directory' >[1=2]
84 	exit 'pwd failed'
85 }
86 
87 h=`{hostname}
88 switch($h){
89 case amsterdam
90 	xdump=/dump/am
91 case *
92 	if(! test -d /dump/$h){
93 		echo 'no dumps on '^`{hostname} >[1=2]
94 		exit 1
95 	}
96 	xdump=/dump/$h
97 }
98 
99 for(i){
100 	xpath=$i
101 	if(! ~ $xpath /*)
102 		xpath=`{9 cleanname -d `{pwd} $i}
103 	dumppath=$xpath
104 	if(~ $#last 0)
105 		xlast=`{9 ls -t $xdump/$year|sed 1q}
106 	if not
107 		xlast=$xdump/$last
108 	$copy $xlast^$dumppath $xpath
109 }