xref: /dragonfly/lib/libhammer/info.c (revision 246dc83d)
1 /*
2  * Copyright (c) 2011 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Antonio Huete <tuxillo@quantumachine.net>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <dirent.h>
36 #include <err.h>
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <sys/param.h>
43 #include <sys/stat.h>
44 #include <unistd.h>
45 
46 #include "libhammer.h"
47 
48 static u_int32_t count_snapshots(u_int32_t, char *, char *, int *);
49 
50 libhammer_volinfo_t
51 libhammer_get_volinfo(const char *path)
52 {
53 	struct hammer_pseudofs_data *pfs_od;
54 	struct hammer_ioc_pfs_iterate pi;
55 	struct hammer_ioc_info info;
56 	libhammer_pfsinfo_t pfstmp;
57 	libhammer_volinfo_t hvi;
58 	int error = 0;
59 	int fd;
60 
61 	if ((fd = open(path, O_RDONLY)) < 0)
62 		return NULL;
63 
64 	hvi = _libhammer_malloc(sizeof(*hvi));
65 	TAILQ_INIT(&hvi->list_pseudo);
66 	if ((ioctl(fd, HAMMERIOC_GET_INFO, &info)) < 0) {
67 		libhammer_free_volinfo(hvi);
68 		close(fd);
69 		return NULL;
70 	}
71 
72 	/* Fill volume information */
73 	snprintf(hvi->vol_name, TXTLEN, "%s", info.vol_name);
74 	hvi->vol_fsid = info.vol_fsid;
75 	hvi->version = info.version;
76 	hvi->nvolumes = info.nvolumes;
77 	hvi->inodes = info.inodes;
78 	hvi->bigblocks = info.bigblocks;
79 	hvi->freebigblocks = info.freebigblocks;
80 	hvi->rsvbigblocks = info.rsvbigblocks;
81 
82 	bzero(&pi, sizeof(pi));
83 	pi.ondisk = _libhammer_malloc(sizeof(*pfs_od));
84 	while(error == 0) {
85 		error = ioctl(fd, HAMMERIOC_PFS_ITERATE, &pi);
86 		if (error == 0 &&
87 		    ((pi.head.flags & HAMMER_PFSD_DELETED) == 0)) {
88 			/*
89 			 * XXX - In the case the path passed is on PFS#0 but it
90 			 * is not the mountpoint itself, it could produce a
91 			 * wrong type of PFS.
92 			 */
93 			pfstmp = _libhammer_malloc(sizeof(*pfstmp));
94 			pfs_od = pi.ondisk;
95 			pfstmp->ismaster =
96 			    (pfs_od->mirror_flags & HAMMER_PFSD_SLAVE) ? 0 : 1;
97 
98 			if (pi.pos == 0)
99 				pfstmp->mountedon = strdup(path);
100 			else
101 				pfstmp->mountedon =
102 				    libhammer_find_pfs_mount(pi.pos,
103 					hvi->vol_fsid, pfstmp->ismaster);
104 			/*
105 			 * Fill in structs used in the library. We don't rely on
106 			 * HAMMER own struct but we do fill our own.
107 			 */
108 			pfstmp->version = hvi->version;
109 			pfstmp->pfs_id = pi.pos;
110 			pfstmp->mirror_flags = pfs_od->mirror_flags;
111 			pfstmp->beg_tid = pfs_od->sync_beg_tid;
112 			pfstmp->end_tid = pfs_od->sync_end_tid;
113 			pfstmp->snapcount = count_snapshots(hvi->version,
114 			    pfstmp->snapshots, pfstmp->mountedon,
115 			    &pfstmp->head.error);
116 
117 			TAILQ_INSERT_TAIL(&hvi->list_pseudo, pfstmp, entries);
118 		}
119 		pi.pos++;
120 	}
121 	free(pi.ondisk);
122 
123 	close (fd);
124 
125 	return (hvi);
126 }
127 
128 void
129 libhammer_free_volinfo(libhammer_volinfo_t volinfo)
130 {
131 	struct libhammer_pfsinfo *pfstmp;
132 
133 	while(!TAILQ_EMPTY(&volinfo->list_pseudo)) {
134 		pfstmp = TAILQ_FIRST(&volinfo->list_pseudo);
135 		free(pfstmp->mountedon);
136 		TAILQ_REMOVE(&volinfo->list_pseudo, pfstmp, entries);
137 		free(pfstmp);
138 	}
139 	free(volinfo);
140 }
141 
142 static u_int32_t
143 count_snapshots(u_int32_t version, char *pfs_snapshots, char *mountedon,
144     int *errorp)
145 {
146 	struct hammer_ioc_snapshot snapinfo;
147 	char *snapshots_path, *fpath;
148 	struct dirent *den;
149 	struct stat st;
150 	DIR *dir;
151 	u_int32_t snapshot_count;
152 	int fd;
153 
154 	snapshot_count = 0;
155 
156 	bzero(&snapinfo, sizeof(struct hammer_ioc_snapshot));
157 
158 	fd = open(mountedon, O_RDONLY);
159 	if (fd < 0) {
160 		*errorp = errno;
161 		return 0;
162 	}
163 
164 	if (version < 3) {
165 		/*
166 		 * old style: count the number of softlinks in the snapshots dir
167 		 */
168 		if (pfs_snapshots[0])
169 			snapshots_path = pfs_snapshots;
170 		else
171 			asprintf(&snapshots_path, "%s/snapshots", mountedon);
172 		if ((dir = opendir(snapshots_path)) != NULL) {
173 			while ((den = readdir(dir)) != NULL) {
174 				if (den->d_name[0] == '.')
175 					continue;
176 				asprintf(&fpath, "%s/%s", snapshots_path,
177 				    den->d_name);
178 				if (lstat(fpath, &st) == 0 &&
179 				    S_ISLNK(st.st_mode))
180 					snapshot_count++;
181 				free(fpath);
182 			}
183 			closedir(dir);
184 		}
185 	} else {
186 		/*
187 		 * new style: file system meta-data
188 		 */
189 		do {
190 			if (ioctl(fd, HAMMERIOC_GET_SNAPSHOT, &snapinfo) < 0) {
191 				*errorp = errno;
192 				goto out;
193 			}
194 
195 			snapshot_count += snapinfo.count;
196 		} while (snapinfo.head.error == 0 && snapinfo.count);
197 	}
198 
199 out:
200 	if (!pfs_snapshots[0])
201 		free(snapshots_path);
202 	if (fd != -1)
203 		close(fd);
204 	return snapshot_count;
205 }
206