summaryrefslogtreecommitdiff
path: root/hlink.c
blob: 487978e2c7e813521c4d8d6cae0e7a439b88efcf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
/*
   Copyright (C) Andrew Tridgell 1996
   Copyright (C) Paul Mackerras 1996
   Copyright (C) 2002 by Martin Pool <mbp@samba.org>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "rsync.h"

extern int dry_run;
extern int verbose;
extern int make_backups;
extern struct file_list *the_file_list;

#ifdef SUPPORT_HARD_LINKS

#define FPTR(i) (the_file_list->files[i])
#define LINKED(p1,p2) (FPTR(p1)->F_DEV == FPTR(p2)->F_DEV \
		    && FPTR(p1)->F_INODE == FPTR(p2)->F_INODE)

static int hlink_compare(int *int1, int *int2)
{
	struct file_struct *f1 = FPTR(*int1);
	struct file_struct *f2 = FPTR(*int2);

	if (f1->F_DEV != f2->F_DEV)
		return (int) (f1->F_DEV > f2->F_DEV ? 1 : -1);

	if (f1->F_INODE != f2->F_INODE)
		return (int) (f1->F_INODE > f2->F_INODE ? 1 : -1);

	return f_name_cmp(f1, f2);
}

static int *hlink_list;
static int hlink_count;

/* Analyze the data in the hlink_list[], remove items that aren't multiply
 * linked, and replace the dev+inode data with the hlindex+next linked list. */
static void link_idev_data(void)
{
	int head, from, to, start;

	alloc_pool_t hlink_pool;
	alloc_pool_t idev_pool = the_file_list->hlink_pool;

	hlink_pool = pool_create(128 * 1024, sizeof (struct hlink),
	    out_of_memory, POOL_INTERN);

	for (from = to = 0; from < hlink_count; from++) {
		start = from;
		head = hlink_list[start];
		while (from < hlink_count-1
		    && LINKED(hlink_list[from], hlink_list[from+1])) {
			pool_free(idev_pool, 0, FPTR(hlink_list[from])->link_u.idev);
			FPTR(hlink_list[from])->link_u.links = pool_talloc(hlink_pool,
			    struct hlink, 1, "hlink_list");

			FPTR(hlink_list[from])->F_HLINDEX = to;
			FPTR(hlink_list[from])->F_NEXT = hlink_list[from+1];
			from++;
		}
		if (from > start) {
			pool_free(idev_pool, 0, FPTR(hlink_list[from])->link_u.idev);
			FPTR(hlink_list[from])->link_u.links = pool_talloc(hlink_pool,
			    struct hlink, 1, "hlink_list");

			FPTR(head)->flags |= FLAG_HLINK_TOL;
			FPTR(hlink_list[from])->F_HLINDEX = to;
			FPTR(hlink_list[from])->F_NEXT = head;
			FPTR(hlink_list[from])->flags |= FLAG_HLINK_EOL;
			hlink_list[to++] = head;
		} else {
			pool_free(idev_pool, 0, FPTR(head)->link_u.idev);
			FPTR(head)->link_u.idev = NULL;
		}
	}

	if (!to) {
		free(hlink_list);
		hlink_list = NULL;
		pool_destroy(hlink_pool);
		hlink_pool = NULL;
	} else {
		hlink_count = to;
		hlink_list = realloc_array(hlink_list, int, hlink_count);
		if (!hlink_list)
			out_of_memory("init_hard_links");
	}
	the_file_list->hlink_pool = hlink_pool;
	pool_destroy(idev_pool);
}
#endif

void init_hard_links(void)
{
#ifdef SUPPORT_HARD_LINKS
	int i;

	if (the_file_list->count < 2)
		return;

	if (hlink_list)
		free(hlink_list);

	if (!(hlink_list = new_array(int, the_file_list->count)))
		out_of_memory("init_hard_links");

	hlink_count = 0;
	for (i = 0; i < the_file_list->count; i++) {
		if (FPTR(i)->link_u.idev)
			hlink_list[hlink_count++] = i;
	}

	qsort(hlink_list, hlink_count,
	    sizeof hlink_list[0], (int (*)()) hlink_compare);

	if (!hlink_count) {
		free(hlink_list);
		hlink_list = NULL;
	} else
		link_idev_data();
#endif
}

int hard_link_check(struct file_struct *file, int ndx, int skip)
{
#ifdef SUPPORT_HARD_LINKS
	if (!hlink_list || !file->link_u.links)
		return 0;
	if (skip && !(file->flags & FLAG_HLINK_EOL))
		hlink_list[file->F_HLINDEX] = file->F_NEXT;
	if (hlink_list[file->F_HLINDEX] != ndx) {
		if (verbose > 2) {
			rprintf(FINFO, "\"%s\" is a hard link\n",
				safe_fname(f_name(file)));
		}
		return 1;
	}
#endif
	return 0;
}

#ifdef SUPPORT_HARD_LINKS
int hard_link_one(struct file_struct *file, int ndx, char *fname,
		  int statret, STRUCT_STAT *st, char *toname, int terse,
		  int itemizing, enum logcode code)
{
	if (do_link(toname, fname)) {
		if (verbose) {
			rsyserr(FERROR, errno, "link %s => %s failed",
				full_fname(fname), safe_fname(toname));
		}
		return -1;
	}

	if (itemizing) {
		itemize(file, ndx, statret, st, ITEM_HARD_LINKED,
			terse ? "" : toname);
	}
	if (code && verbose && !terse) {
		rprintf(code, "%s => %s\n",
			safe_fname(fname), safe_fname(toname));
	}
	return 0;
}
#endif


void hard_link_cluster(struct file_struct *file, int master, int itemizing,
		       enum logcode code)
{
#ifdef SUPPORT_HARD_LINKS
	char hlink1[MAXPATHLEN];
	char *hlink2;
	STRUCT_STAT st1, st2;
	int statret, ndx = master;

	if (link_stat(f_name_to(file, hlink1), &st1, 0) < 0)
		return;
	if (!(file->flags & FLAG_HLINK_TOL)) {
		while (!(file->flags & FLAG_HLINK_EOL)) {
			ndx = file->F_NEXT;
			file = FPTR(ndx);
		}
	}
	do {
		ndx = file->F_NEXT;
		file = FPTR(ndx);
		if (ndx == master)
			continue;
		hlink2 = f_name(file);
		if ((statret = link_stat(hlink2, &st2, 0)) == 0) {
			if (st2.st_dev == st1.st_dev
			    && st2.st_ino == st1.st_ino) {
				if (itemizing) {
					itemize(file, ndx, statret,
						&st2, ITEM_HARD_LINKED, "");
				}
				continue;
			}
			if (make_backups) {
				if (!make_backup(hlink2))
					continue;
			} else if (robust_unlink(hlink2)) {
				if (verbose > 0) {
					rsyserr(FINFO, errno,
						"unlink %s failed",
						full_fname(hlink2));
				}
				continue;
			}
		}
		hard_link_one(file, ndx, hlink2, statret,
			      &st2, hlink1, 0, itemizing, code);
	} while (!(file->flags & FLAG_HLINK_EOL));
#endif
}