1 #include <u.h>
2 #include <libc.h>
3 #include <bio.h>
4 #include <regexp.h>
5 #include <ctype.h>
6 
7 typedef struct Date	Date;
8 struct Date {
9 	Reprog *p;	/* an RE to match this date */
10 	Date *next;	/* pointer to next in list */
11 };
12 
13 enum{
14 	Secondsperday = 24*60*60
15 };
16 
17 Biobuf in;
18 int debug, matchyear;
19 
20 Date *dates(Date**, Tm*);
21 void upper2lower(char*, char*, int);
22 void *alloc(unsigned int);
23 
24 void
25 main(int argc, char *argv[])
26 {
27 	int i, fd, ahead;
28 	long now;
29 	char *line;
30 	Tm *tm;
31 	Date *first, *last, *d;
32 	char buf[1024];
33 
34 	ahead = 0;
35 	ARGBEGIN{
36 	case 'y':
37 		matchyear = 1;
38 		break;
39 	case 'd':
40 		debug = 1;
41 		break;
42 	case 'p':
43 		ahead = atoi(ARGF());
44 		break;
45 	default:
46 		fprint(2, "usage: calendar [-y] [-d] [files ...]\n");
47 		exits("usage");
48 	}ARGEND;
49 
50 	/* make a list of dates */
51 	now = time(0);
52 	tm = localtime(now);
53 	last = nil;
54 	first = dates(&last, tm);
55 	now += Secondsperday;
56 	tm = localtime(now);
57 	dates(&last, tm);
58 	if(tm->wday == 6){
59 		now += Secondsperday;
60 		tm = localtime(now);
61 		dates(&last, tm);
62 	}
63 	if(tm->wday == 0){
64 		now += Secondsperday;
65 		tm = localtime(now);
66 		dates(&last, tm);
67 	}
68 	if(ahead){
69 		now = time(0);
70 		now += ahead * Secondsperday;
71 		tm = localtime(now);
72 		dates(&last, tm);
73 	}
74 
75 	for(i=0; i<argc || (i==0 && argc==0); i++){
76 		if(i==0 && argc==0)
77 			snprint(buf, sizeof(buf),
78 				"%s/lib/calendar", getenv("HOME"));
79 		else
80 			strcpy(buf, argv[i]);
81 		fd = open(buf, OREAD);
82 		if(fd<0 || Binit(&in, fd, OREAD)<0){
83 			fprint(2, "calendar: can't open %s: %r\n", buf);
84 			exits("open");
85 		}
86 
87 		/* go through the file */
88 		while(line = Brdline(&in, '\n')){
89 			line[Blinelen(&in) - 1] = 0;
90 			upper2lower(buf, line, sizeof buf);
91 			for(d=first; d; d=d->next)
92 				if(regexec(d->p, buf, 0, 0)){
93 					print("%s\n", line);
94 					break;
95 				}
96 		}
97 		close(fd);
98 	}
99 	exits("");
100 }
101 
102 char *months[] =
103 {
104 	"january",
105 	"february",
106 	"march",
107 	"april",
108 	"may",
109 	"june",
110 	"july",
111 	"august",
112 	"september",
113 	"october",
114 	"november",
115 	"december"
116 };
117 
118 /*
119  * Generate two Date structures.  First has month followed by day;
120  * second has day followed by month.  Link them into list after
121  * last, and return the first.
122  */
123 Date*
124 dates(Date **last, Tm *tm)
125 {
126 	Date *first;
127 	Date *nd;
128 	char mo[128], buf[128];
129 
130 	if(utflen(months[tm->mon]) > 3)
131 		snprint(mo, sizeof mo, "%3.3s(%s)?",
132 			months[tm->mon], months[tm->mon]+3);
133 	else
134 		snprint(mo, sizeof mo, "%3.3s", months[tm->mon]);
135 	if (matchyear)
136 		snprint(buf, sizeof buf,
137 			"(^| |\t)((%s( |\t)+)|(%d/))%d( |\t|$)(((%d|%d)( |\t|$))|[^0-9]|([0-9]+[^0-9 \t]))",
138 			mo, tm->mon+1, tm->mday, tm->year+1900, tm->year%100);
139 	else
140 		snprint(buf, sizeof buf,
141 			"(^| |\t)((%s( |\t)+)|(%d/))%d( |\t|$)",
142 			mo, tm->mon+1, tm->mday);
143 	if(debug)
144 		print("%s\n", buf);
145 
146 	first = alloc(sizeof(Date));
147 	if(*last)
148 		(*last)->next = first;
149 	first->p = regcomp(buf);
150 
151 	if (matchyear)
152 		snprint(buf, sizeof buf,
153 			"(^| |\t)%d( |\t)+(%s)( |\t|$)(((%d|%d)( |\t|$))|[^0-9]|([0-9]+[^0-9 \t]))",
154 			tm->mday, mo, tm->year+1900, tm->year%100);
155 	else
156 		snprint(buf, sizeof buf,
157 			"(^| |\t)%d( |\t)+(%s)( |\t|$)",
158 			tm->mday, mo);
159 	if(debug)
160 		print("%s\n", buf);
161 	nd = alloc(sizeof(Date));
162 	nd->p = regcomp(buf);
163 	nd->next = 0;
164 	first->next = nd;
165 	*last = nd;
166 
167 	return first;
168 }
169 
170 /*
171  * Copy 'from' to 'to', converting to lower case
172  */
173 void
174 upper2lower(char *to, char *from, int len)
175 {
176 	while(--len>0 && *from!='\0')
177 		*to++ = tolower((uchar)*from++);
178 	*to = 0;
179 }
180 
181 /*
182  * Call malloc and check for errors
183  */
184 void*
185 alloc(unsigned int n)
186 {
187 	void *p;
188 
189 	p = malloc(n);
190 	if(p == 0){
191 		fprint(2, "calendar: malloc failed: %r\n");
192 		exits("malloc");
193 	}
194 	return p;
195 }