File: bpc_dirOps.c

package info (click to toggle)
libbackuppc-xs-perl 0.62-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 1,348 kB
  • sloc: ansic: 9,652; sh: 3,084; perl: 73; makefile: 3
file content (300 lines) | stat: -rw-r--r-- 10,591 bytes parent folder | download | duplicates (3)
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
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
/*
 * Directory and file system operations
 *
 * Copyright (C) 2013 Craig Barratt.
 *
 * 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 3 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, visit the http://fsf.org website.
 */

#include "backuppc.h"

/*
 * Create all the directories in the given path.  Path must be non-const.  Trailing '/' characters are removed.
 */
int bpc_path_create(char *path)
{
    char *p = path;
    STRUCT_STAT st;
    int levels = 0;

    if ( BPC_LogLevel >= 6 ) bpc_logMsgf("bpc_path_create(%s)\n", path);
    /*
     * check if it exists already
     */
    if ( !stat(path, &st) && S_ISDIR(st.st_mode) ) return 0;

    /*
     * We walk up until we find the deepest level directory that exists.
     * First remove trailing slashes.
     */
    p = path + strlen(path);
    while ( p > path && p[-1] == '/' ) p--;
    if ( *p == '/' ) *p = '\0';
    while ( p > path ) {
        while ( p > path && p[-1] != '/' ) p--;
        while ( p > path && p[-1] == '/' ) p--;
        if ( *p == '/' ) {
            *p = '\0';
            levels++;
            if ( !stat(path, &st) && S_ISDIR(st.st_mode) ) break;
        }
    }
    if ( BPC_LogLevel >= 9 ) bpc_logMsgf("bpc_path_create: found that %s exists (%d levels up)\n", path, levels);

    /*
     * We have removed levels '/' characters from path.  Replace each one and create the directory.
     */
    while ( levels-- > 0 ) {
        p = path + strlen(path);
        *p = '/';
        if ( mkdir(path, ACCESSPERMS) < 0 && errno != EEXIST) {
            bpc_logErrf("bpc_path_create: can't create %s (errno %d)\n", path, errno);
            return -1;
        }
        if ( BPC_LogLevel >= 9 ) bpc_logMsgf("bpc_path_create: created %s\n", path);
    }
    return 0;
}

/*
 * Remove all the files below path (if a directory) and path itself.  Deduct reference counts
 * for every attrib file removed.
 *
 * Note that inodes are *not* updated, even in cases where nlinks > 0.
 */
int bpc_path_remove(bpc_deltaCount_info *deltaInfo, char *path, int compress)
{
    char filePath[BPC_MAXPATHLEN];
    STRUCT_STAT st;
    DIR *dir;
    struct dirent *dp;
    int errorCnt = 0;
    size_t dirListSize = 0, dirListLen = 0;
    char *dirList = NULL, *dirListP;

    if ( BPC_LogLevel >= 6 ) bpc_logMsgf("bpc_path_remove(%s)\n", path);
    if ( !(dir = opendir(path)) ) {
        unlink(path);
        return errorCnt;
    }
    while ( (dp = readdir(dir)) ) {
        if ( !strcmp(dp->d_name, ".") || !strcmp(dp->d_name, "..") ) continue;
        snprintf(filePath, sizeof(filePath), "%s/%s", path, dp->d_name);
        if ( BPC_LogLevel >= 8 ) bpc_logMsgf("bpc_path_remove: removing %s\n", filePath);
        if ( stat(filePath, &st) ) {
            /*
             * hmmm.  stat failed - just try to remove it
             */
            unlink(filePath);
            continue;
        }
        if ( S_ISDIR(st.st_mode) ) {
            /*
             * To avoid recursing with dir still open (consuming an open fd), remember all the dirs
             * and recurse after we close dir.
             */
            if ( !dirList ) {
                dirListSize = 4096;
                if ( !(dirList = malloc(dirListSize)) ) {
                    bpc_logErrf("bpc_path_remove: can't allocate %u bytes\n", (unsigned)dirListSize);
                    return ++errorCnt;
                }
            }
            if ( dirListLen + strlen(dp->d_name) + 1 >= dirListSize ) {
                dirListSize = dirListSize * 2 + strlen(dp->d_name);
                if ( !(dirList = realloc(dirList, dirListSize)) ) {
                    bpc_logErrf("bpc_path_remove: can't reallocate %u bytes\n", (unsigned)dirListSize);
                    return ++errorCnt;
                }
            }
            strcpy(dirList + dirListLen, dp->d_name);
            dirListLen += strlen(dp->d_name) + 1;
        } else {
            /*
             * if this is an attrib file, we need to read it and deduct the reference counts.
             */
            if ( !strncmp(dp->d_name, "attrib", 6) ) {
                bpc_attrib_dir dir;

                bpc_attrib_dirInit(&dir, compress);
                if ( bpc_attrib_dirRead(&dir, NULL, filePath, 0) ) {
                    bpc_logErrf("bpc_path_remove: can't read attrib file %s\n", filePath);
                    errorCnt++;
                }
                if ( BPC_LogLevel >= 9 ) bpc_logMsgf("bpc_path_remove: adjusting ref counts from attrib file %s\n", filePath);
                if ( !unlink(filePath) ) {
                    /*
                     * Only reduce the ref counts if we succeeded in removing the attrib file
                     */
                    bpc_attrib_dirRefCount(deltaInfo, &dir, -1);
                }
                bpc_attrib_dirDestroy(&dir);
            } else {
                if ( unlink(filePath) ) errorCnt++;
            }
        }
    }
    closedir(dir);
    /*
     * Now visit the subdirs we have saved above.
     */
    if ( dirList ) {
        for ( dirListP = dirList ; dirListP < dirList + dirListLen ; dirListP += strlen(dirListP) + 1 ) {
            snprintf(filePath, sizeof(filePath), "%s/%s", path, dirListP);
            errorCnt += bpc_path_remove(deltaInfo, filePath, compress);
        }
        free(dirList);
    }
    if ( rmdir(path) ) errorCnt++;
    return errorCnt;
}

/*
 * Reference count all the files below the directory path, based on the attrib
 * files in and below path.
 */
int bpc_path_refCountAllInodeMax(bpc_deltaCount_info *deltaInfo, char *path, int compress, int incr, unsigned int *inodeMax)
{
    char filePath[BPC_MAXPATHLEN];
    STRUCT_STAT st;
    DIR *dir;
    struct dirent *dp;
    int errorCnt = 0;
    size_t dirListSize = 0, dirListLen = 0;
    char *dirList = NULL, *dirListP;

    if ( BPC_LogLevel >= 6 ) bpc_logMsgf("bpc_path_refCountAll(%s)\n", path);
    if ( !(dir = opendir(path)) ) {
        return errorCnt;
    }
    while ( (dp = readdir(dir)) ) {
        if ( !strcmp(dp->d_name, ".") || !strcmp(dp->d_name, "..") ) continue;
        snprintf(filePath, sizeof(filePath), "%s/%s", path, dp->d_name);
        if ( BPC_LogLevel >= 8 ) bpc_logMsgf("bpc_path_refCountAll: got %s\n", filePath);
        if ( stat(filePath, &st) ) continue;
        if ( S_ISDIR(st.st_mode) ) {
            /*
             * To avoid recursing with dir still open (consuming an open fd), remember all the dirs
             * and recurse after we close dir.
             */
            if ( !dirList ) {
                dirListSize = 4096;
                if ( !(dirList = malloc(dirListSize)) ) {
                    bpc_logErrf("bpc_path_refCountAll: can't allocate %u bytes\n", (unsigned)dirListSize);
                    return ++errorCnt;
                }
            }
            if ( dirListLen + strlen(dp->d_name) + 1 >= dirListSize ) {
                dirListSize = dirListSize * 2 + strlen(dp->d_name);
                if ( !(dirList = realloc(dirList, dirListSize)) ) {
                    bpc_logErrf("bpc_path_refCountAll: can't reallocate %u bytes\n", (unsigned)dirListSize);
                    return ++errorCnt;
                }
            }
            strcpy(dirList + dirListLen, dp->d_name);
            dirListLen += strlen(dp->d_name) + 1;
        } else {
            /*
             * if this is an attrib file, we need to read it and deduct the reference counts.
             */
            if ( !strncmp(dp->d_name, "attrib", 6) ) {
                bpc_attrib_dir dir;

                bpc_attrib_dirInit(&dir, compress);
                if ( bpc_attrib_dirRead(&dir, path, dp->d_name, 0) ) {
                    bpc_logErrf("bpc_path_refCountAll: can't read attrib file %s\n", filePath);
                    errorCnt++;
                } else {
                    if ( BPC_LogLevel >= 9 ) bpc_logMsgf("bpc_path_refCountAll: adjusting ref counts from attrib file %s\n", filePath);
                    bpc_attrib_dirRefCountInodeMax(deltaInfo, &dir, incr, inodeMax);
                }
                bpc_attrib_dirDestroy(&dir);
            }
        }
    }
    closedir(dir);
    /*
     * Now visit the subdirs we have saved above.
     */
    if ( dirList ) {
        for ( dirListP = dirList ; dirListP < dirList + dirListLen ; dirListP += strlen(dirListP) + 1 ) {
            snprintf(filePath, sizeof(filePath), "%s/%s", path, dirListP);
            errorCnt += bpc_path_refCountAllInodeMax(deltaInfo, filePath, compress, incr, inodeMax);
        }
        free(dirList);
    }
    return errorCnt;
}

/*
 * Reference count all the files below the directory path, based on the attrib
 * files in and below path.
 */
int bpc_path_refCountAll(bpc_deltaCount_info *deltaInfo, char *path, int compress, int incr)
{
    return bpc_path_refCountAllInodeMax(deltaInfo, path, compress, incr, NULL);
}

/*
 * Add an exclusive lock to the byte range in the given file.
 * Blocks until the lock becomes available.
 */
int bpc_lockRangeFd(int fd, OFF_T offset, OFF_T len, int block)
{
    struct flock lock;

    lock.l_type   = F_WRLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start  = offset;
    lock.l_len    = len;
    lock.l_pid    = 0;

    return fcntl(fd, block ? F_SETLKW : F_SETLK, &lock);
}

int bpc_unlockRangeFd(int fd, OFF_T offset, OFF_T len)
{
    struct flock lock;

    lock.l_type   = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start  = offset;
    lock.l_len    = len;
    lock.l_pid    = 0;

    return fcntl(fd, F_SETLK, &lock);
}

int bpc_lockRangeFile(char *lockFile, OFF_T offset, OFF_T len, int block)
{
    int fd;

    if ( (fd = open(lockFile, O_CREAT | O_RDWR, 0660)) < 0 ) {
        bpc_logErrf("bpc_lockRangeFile: can't open/create lock file %s\n", lockFile);
        return fd;
    }
    if ( bpc_lockRangeFd(fd, offset, len, block) ) {
        close(fd);
        if ( block ) {
            bpc_logErrf("bpc_lockRangeFile: lock(%s) failed (errno = %d)\n", lockFile, errno);
        }
        return -1;
    }
    return fd;
}

void bpc_unlockRangeFile(int lockFd)
{
    if ( lockFd >= 0 ) close(lockFd);
}