1 /*
2  *	news foo	prints /lib/news/foo
3  *	news -a		prints all news items, latest first
4  *	news -n		lists names of new items
5  *	news		prints items changed since last news
6  */
7 
8 #include <u.h>
9 #include <libc.h>
10 #include <bio.h>
11 
12 #define	NINC	50	/* Multiples of directory allocation */
13 char	*NEWS = "#9/news";
14 char	TFILE[] = "%s/lib/newstime";
15 
16 /*
17  *	The following items should not be printed.
18  */
19 char*	ignore[] =
20 {
21 	"core",
22 	"dead.letter",
23 	0
24 };
25 
26 typedef
27 struct
28 {
29 	long	time;
30 	char	*name;
31 	vlong	length;
32 } File;
33 File*	n_list;
34 int	n_count;
35 int	n_items;
36 Biobuf	bout;
37 
38 int	fcmp(const void *a, const void *b);
39 void	read_dir(int update);
40 void	print_item(char *f);
41 void	eachitem(void (*emit)(char*), int all, int update);
42 void	note(char *s);
43 
44 void
45 main(int argc, char *argv[])
46 {
47 	int i;
48 
49 	NEWS = unsharp(NEWS);
50 
51 	Binit(&bout, 1, OWRITE);
52 	if(argc == 1) {
53 		eachitem(print_item, 0, 1);
54 		exits(0);
55 	}
56 	ARGBEGIN{
57 	case 'a':	/* print all */
58 		eachitem(print_item, 1, 0);
59 		break;
60 
61 	case 'n':	/* names only */
62 		eachitem(note, 0, 0);
63 		if(n_items)
64 			Bputc(&bout, '\n');
65 		break;
66 
67 	default:
68 		fprint(2, "news: bad option %c\n", ARGC());
69 		exits("usage");
70 	}ARGEND
71 	for(i=0; i<argc; i++)
72 		print_item(argv[i]);
73 	exits(0);
74 }
75 
76 int
77 fcmp(const void *a, const void *b)
78 {
79 	long x;
80 
81 	x = ((File*)b)->time - ((File*)a)->time;
82 	if(x < 0)
83 		return -1;
84 	if(x > 0)
85 		return 1;
86 	return 0;
87 }
88 
89 /*
90  *	read_dir: get the file names and modification dates for the
91  *	files in /usr/news into n_list; sort them in reverse by
92  *	modification date.
93  */
94 void
95 read_dir(int update)
96 {
97 	Dir *d;
98 	char newstime[100], *home;
99 	int i, j, n, na, fd;
100 
101 	n_count = 0;
102 	n_list = malloc(NINC*sizeof(File));
103 	na = NINC;
104 	home = getenv("HOME");
105 	if(home) {
106 		sprint(newstime, TFILE, home);
107 		d = dirstat(newstime);
108 		if(d != nil) {
109 			n_list[n_count].name = strdup("");
110 			n_list[n_count].time =d->mtime-1;
111 			n_list[n_count].length = 0;
112 			n_count++;
113 			free(d);
114 		}
115 		if(update) {
116 			fd = create(newstime, OWRITE, 0644);
117 			if(fd >= 0)
118 				close(fd);
119 		}
120 	}
121 	fd = open(NEWS, OREAD);
122 	if(fd < 0) {
123 		fprint(2, "news: ");
124 		perror(NEWS);
125 		exits(NEWS);
126 	}
127 
128 	n = dirreadall(fd, &d);
129 	for(i=0; i<n; i++) {
130 		for(j=0; ignore[j]; j++)
131 			if(strcmp(ignore[j], d[i].name) == 0)
132 				goto ign;
133 		if(na <= n_count) {
134 			na += NINC;
135 			n_list = realloc(n_list, na*sizeof(File));
136 		}
137 		n_list[n_count].name = strdup(d[i].name);
138 		n_list[n_count].time = d[i].mtime;
139 		n_list[n_count].length = d[i].length;
140 		n_count++;
141 	ign:;
142 	}
143 	free(d);
144 
145 	close(fd);
146 	qsort(n_list, n_count, sizeof(File), fcmp);
147 }
148 
149 void
150 print_item(char *file)
151 {
152 	char name[4096], *p, *ep;
153 	Dir *dbuf;
154 	int f, c;
155 	int bol, bop;
156 
157 	sprint(name, "%s/%s", NEWS, file);
158 	f = open(name, OREAD);
159 	if(f < 0) {
160 		fprint(2, "news: ");
161 		perror(name);
162 		return;
163 	}
164 	strcpy(name, "...");
165 	dbuf = dirfstat(f);
166 	if(dbuf == nil)
167 		return;
168 	Bprint(&bout, "\n%s (%s) %s\n", file,
169 		dbuf->muid[0]? dbuf->muid : dbuf->uid,
170 		asctime(localtime(dbuf->mtime)));
171 	free(dbuf);
172 
173 	bol = 1;	/* beginning of line ...\n */
174 	bop = 1;	/* beginning of page ...\n\n */
175 	for(;;) {
176 		c = read(f, name, sizeof(name));
177 		if(c <= 0)
178 			break;
179 		p = name;
180 		ep = p+c;
181 		while(p < ep) {
182 			c = *p++;
183 			if(c == '\n') {
184 				if(!bop) {
185 					Bputc(&bout, c);
186 					if(bol)
187 						bop = 1;
188 					bol = 1;
189 				}
190 				continue;
191 			}
192 			if(bol) {
193 				Bputc(&bout, '\t');
194 				bol = 0;
195 				bop = 0;
196 			}
197 			Bputc(&bout, c);
198 		}
199 	}
200 	if(!bol)
201 		Bputc(&bout, '\n');
202 	close(f);
203 }
204 
205 void
206 eachitem(void (*emit)(char*), int all, int update)
207 {
208 	int i;
209 
210 	read_dir(update);
211 	for(i=0; i<n_count; i++) {
212 		if(n_list[i].name[0] == 0) {	/* newstime */
213 			if(all)
214 				continue;
215 			break;
216 		}
217 		if(n_list[i].length == 0)		/* in progress */
218 			continue;
219 		(*emit)(n_list[i].name);
220 	}
221 }
222 
223 void
224 note(char *file)
225 {
226 
227 	if(!n_items)
228 		Bprint(&bout, "news:");
229 	Bprint(&bout, " %s", file);
230 	n_items++;
231 }