Subversion Repositories planix.SVN

Rev

Rev 2 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2 - 1 
#include <u.h>
2 
#include <libc.h>
3 
#include <bio.h>
4 
#include <ctype.h>
5 
#include <ndb.h>
6 
#include "ndbhf.h"
7 
 
8 
static Ndb*	doopen(char*);
9 
static void	hffree(Ndb*);
10 
 
11 
static char *deffile = "/lib/ndb/local";
12 
 
13 
/*
14 
 *  the database entry in 'file' indicates the list of files
15 
 *  that makeup the database.  Open each one and search in
16 
 *  the same order.
17 
 */
18 
Ndb*
19 
ndbopen(char *file)
20 
{
21 
	Ndb *db, *first, *last;
22 
	Ndbs s;
23 
	Ndbtuple *t, *nt;
24 
 
25 
	if(file == nil && (file = getenv("NDBFILE")) == nil)
26 
		file = deffile;
27 
	db = doopen(file);
28 
	if(db == 0)
29 
		return 0;
30 
	first = last = db;
31 
	t = ndbsearch(db, &s, "database", "");
32 
	Bseek(&db->b, 0, 0);
33 
	if(t == 0)
34 
		return db;
35 
	for(nt = t; nt; nt = nt->entry){
36 
		if(strcmp(nt->attr, "file") != 0)
37 
			continue;
38 
		if(strcmp(nt->val, file) == 0){
39 
			/* default file can be reordered in the list */
40 
			if(first->next == 0)
41 
				continue;
42 
			if(strcmp(first->file, file) == 0){
43 
				db = first;
44 
				first = first->next;
45 
				last->next = db;
46 
				db->next = 0;
47 
				last = db;
48 
			}
49 
			continue;
50 
		}
51 
		db = doopen(nt->val);
52 
		if(db == 0)
53 
			continue;
54 
		last->next = db;
55 
		last = db;
56 
	}
57 
	ndbfree(t);
58 
	return first;
59 
}
60 
 
61 
/*
62 
 *  open a single file
63 
 */
64 
static Ndb*
65 
doopen(char *file)
66 
{
67 
	Ndb *db;
68 
 
69 
	db = (Ndb*)malloc(sizeof(Ndb));
70 
	if(db == 0)
71 
		return 0;
72 
	memset(db, 0, sizeof(Ndb));
73 
	strncpy(db->file, file, sizeof(db->file)-1);
74 
 
75 
	if(ndbreopen(db) < 0){
76 
		free(db);
77 
		return 0;
78 
	}
79 
 
80 
	return db;
81 
}
82 
 
83 
/*
84 
 *  dump any cached information, forget the hash tables, and reopen a single file
85 
 */
86 
int
87 
ndbreopen(Ndb *db)
88 
{
89 
	int fd;
90 
	Dir *d;
91 
 
92 
	/* forget what we know about the open files */
93 
	if(db->mtime){
94 
		_ndbcacheflush(db);
95 
		hffree(db);
96 
		close(Bfildes(&db->b));
97 
		Bterm(&db->b);
98 
		db->mtime = 0;
99 
	}
100 
 
101 
	/* try the open again */
102 
	fd = open(db->file, OREAD);
103 
	if(fd < 0)
104 
		return -1;
105 
	d = dirfstat(fd);
106 
	if(d == nil){
107 
		close(fd);
108 
		return -1;
109 
	}
110 
 
111 
	db->qid = d->qid;
112 
	db->mtime = d->mtime;
113 
	db->length = d->length;
114 
	Binits(&db->b, fd, OREAD, db->buf, sizeof(db->buf));
115 
	free(d);
116 
	return 0;
117 
}
118 
 
119 
/*
120 
 *  close the database files
121 
 */
122 
void
123 
ndbclose(Ndb *db)
124 
{
125 
	Ndb *nextdb;
126 
 
127 
	for(; db; db = nextdb){
128 
		nextdb = db->next;
129 
		_ndbcacheflush(db);
130 
		hffree(db);
131 
		close(Bfildes(&db->b));
132 
		Bterm(&db->b);
133 
		free(db);
134 
	}
135 
}
136 
 
137 
/*
138 
 *  free the hash files belonging to a db
139 
 */
140 
static void
141 
hffree(Ndb *db)
142 
{
143 
	Ndbhf *hf, *next;
144 
 
145 
	for(hf = db->hf; hf; hf = next){
146 
		next = hf->next;
147 
		close(hf->fd);
148 
		free(hf);
149 
	}
150 
	db->hf = 0;
151 
}
152 
 
153 
/*
154 
 *  return true if any part of the database has changed
155 
 */
156 
int
157 
ndbchanged(Ndb *db)
158 
{
159 
	Ndb *ndb;
160 
	Dir *d;
161 
 
162 
	for(ndb = db; ndb != nil; ndb = ndb->next){
163 
		d = dirfstat(Bfildes(&ndb->b));
164 
		if(d == nil)
165 
			continue;
166 
		if(ndb->qid.path != d->qid.path
167 
		|| ndb->qid.vers != d->qid.vers){
168 
			free(d);
169 
			return 1;
170 
		}
171 
		free(d);
172 
	}
173 
	return 0;
174 
}