/src/postgres/src/port/pgcheckdir.c
Line | Count | Source (jump to first uncovered line) |
1 | | /*------------------------------------------------------------------------- |
2 | | * |
3 | | * pgcheckdir.c |
4 | | * |
5 | | * A simple subroutine to check whether a directory exists and is empty or not. |
6 | | * Useful in both initdb and the backend. |
7 | | * |
8 | | * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group |
9 | | * Portions Copyright (c) 1994, Regents of the University of California |
10 | | * |
11 | | * IDENTIFICATION |
12 | | * src/port/pgcheckdir.c |
13 | | *------------------------------------------------------------------------- |
14 | | */ |
15 | | |
16 | | #include "c.h" |
17 | | |
18 | | #include <dirent.h> |
19 | | |
20 | | |
21 | | /* |
22 | | * Test to see if a directory exists and is empty or not. |
23 | | * |
24 | | * Returns: |
25 | | * 0 if nonexistent |
26 | | * 1 if exists and empty |
27 | | * 2 if exists and contains _only_ dot files |
28 | | * 3 if exists and contains a mount point |
29 | | * 4 if exists and not empty |
30 | | * -1 if trouble accessing directory (errno reflects the error) |
31 | | */ |
32 | | int |
33 | | pg_check_dir(const char *dir) |
34 | 0 | { |
35 | 0 | int result = 1; |
36 | 0 | DIR *chkdir; |
37 | 0 | struct dirent *file; |
38 | 0 | bool dot_found = false; |
39 | 0 | bool mount_found = false; |
40 | 0 | int readdir_errno; |
41 | |
|
42 | 0 | chkdir = opendir(dir); |
43 | 0 | if (chkdir == NULL) |
44 | 0 | return (errno == ENOENT) ? 0 : -1; |
45 | | |
46 | 0 | while (errno = 0, (file = readdir(chkdir)) != NULL) |
47 | 0 | { |
48 | 0 | if (strcmp(".", file->d_name) == 0 || |
49 | 0 | strcmp("..", file->d_name) == 0) |
50 | 0 | { |
51 | | /* skip this and parent directory */ |
52 | 0 | continue; |
53 | 0 | } |
54 | 0 | #ifndef WIN32 |
55 | | /* file starts with "." */ |
56 | 0 | else if (file->d_name[0] == '.') |
57 | 0 | { |
58 | 0 | dot_found = true; |
59 | 0 | } |
60 | | /* lost+found directory */ |
61 | 0 | else if (strcmp("lost+found", file->d_name) == 0) |
62 | 0 | { |
63 | 0 | mount_found = true; |
64 | 0 | } |
65 | 0 | #endif |
66 | 0 | else |
67 | 0 | { |
68 | 0 | result = 4; /* not empty */ |
69 | 0 | break; |
70 | 0 | } |
71 | 0 | } |
72 | |
|
73 | 0 | if (errno) |
74 | 0 | result = -1; /* some kind of I/O error? */ |
75 | | |
76 | | /* Close chkdir and avoid overwriting the readdir errno on success */ |
77 | 0 | readdir_errno = errno; |
78 | 0 | if (closedir(chkdir)) |
79 | 0 | result = -1; /* error executing closedir */ |
80 | 0 | else |
81 | 0 | errno = readdir_errno; |
82 | | |
83 | | /* We report on mount point if we find a lost+found directory */ |
84 | 0 | if (result == 1 && mount_found) |
85 | 0 | result = 3; |
86 | | |
87 | | /* We report on dot-files if we _only_ find dot files */ |
88 | 0 | if (result == 1 && dot_found) |
89 | 0 | result = 2; |
90 | |
|
91 | 0 | return result; |
92 | 0 | } |