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Commit | Line | Data |
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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
8530dc44 | 2 | |
a8fbdf54 TA |
3 | #include <errno.h> |
4 | #include <stdlib.h> | |
5 | #include <string.h> | |
6 | ||
62d74c78 | 7 | #include "alloc-util.h" |
a8fbdf54 | 8 | #include "macro.h" |
8530dc44 | 9 | #include "uid-range.h" |
b1d4f8e1 | 10 | #include "user-util.h" |
8530dc44 LP |
11 | |
12 | static bool uid_range_intersect(UidRange *range, uid_t start, uid_t nr) { | |
13 | assert(range); | |
14 | ||
15 | return range->start <= start + nr && | |
16 | range->start + range->nr >= start; | |
17 | } | |
18 | ||
19 | static void uid_range_coalesce(UidRange **p, unsigned *n) { | |
20 | unsigned i, j; | |
21 | ||
22 | assert(p); | |
23 | assert(n); | |
24 | ||
25 | for (i = 0; i < *n; i++) { | |
26 | for (j = i + 1; j < *n; j++) { | |
27 | UidRange *x = (*p)+i, *y = (*p)+j; | |
28 | ||
29 | if (uid_range_intersect(x, y->start, y->nr)) { | |
30 | uid_t begin, end; | |
31 | ||
32 | begin = MIN(x->start, y->start); | |
33 | end = MAX(x->start + x->nr, y->start + y->nr); | |
34 | ||
35 | x->start = begin; | |
36 | x->nr = end - begin; | |
37 | ||
38 | if (*n > j+1) | |
39 | memmove(y, y+1, sizeof(UidRange) * (*n - j -1)); | |
40 | ||
313cefa1 | 41 | (*n)--; |
8530dc44 LP |
42 | j--; |
43 | } | |
44 | } | |
45 | } | |
8530dc44 LP |
46 | } |
47 | ||
48 | static int uid_range_compare(const void *a, const void *b) { | |
49 | const UidRange *x = a, *y = b; | |
50 | ||
51 | if (x->start < y->start) | |
52 | return -1; | |
53 | if (x->start > y->start) | |
54 | return 1; | |
55 | ||
56 | if (x->nr < y->nr) | |
57 | return -1; | |
58 | if (x->nr > y->nr) | |
59 | return 1; | |
60 | ||
61 | return 0; | |
62 | } | |
63 | ||
64 | int uid_range_add(UidRange **p, unsigned *n, uid_t start, uid_t nr) { | |
65 | bool found = false; | |
66 | UidRange *x; | |
67 | unsigned i; | |
68 | ||
69 | assert(p); | |
70 | assert(n); | |
71 | ||
72 | if (nr <= 0) | |
73 | return 0; | |
74 | ||
75 | for (i = 0; i < *n; i++) { | |
76 | x = (*p) + i; | |
77 | if (uid_range_intersect(x, start, nr)) { | |
78 | found = true; | |
79 | break; | |
80 | } | |
81 | } | |
82 | ||
83 | if (found) { | |
84 | uid_t begin, end; | |
85 | ||
86 | begin = MIN(x->start, start); | |
87 | end = MAX(x->start + x->nr, start + nr); | |
88 | ||
89 | x->start = begin; | |
90 | x->nr = end - begin; | |
91 | } else { | |
92 | UidRange *t; | |
93 | ||
62d74c78 | 94 | t = reallocarray(*p, *n + 1, sizeof(UidRange)); |
8530dc44 LP |
95 | if (!t) |
96 | return -ENOMEM; | |
97 | ||
98 | *p = t; | |
99 | x = t + ((*n) ++); | |
100 | ||
101 | x->start = start; | |
102 | x->nr = nr; | |
103 | } | |
104 | ||
105 | qsort(*p, *n, sizeof(UidRange), uid_range_compare); | |
106 | uid_range_coalesce(p, n); | |
107 | ||
108 | return *n; | |
109 | } | |
110 | ||
111 | int uid_range_add_str(UidRange **p, unsigned *n, const char *s) { | |
112 | uid_t start, nr; | |
113 | const char *t; | |
114 | int r; | |
115 | ||
116 | assert(p); | |
117 | assert(n); | |
118 | assert(s); | |
119 | ||
120 | t = strchr(s, '-'); | |
121 | if (t) { | |
122 | char *b; | |
123 | uid_t end; | |
124 | ||
125 | b = strndupa(s, t - s); | |
126 | r = parse_uid(b, &start); | |
127 | if (r < 0) | |
128 | return r; | |
129 | ||
130 | r = parse_uid(t+1, &end); | |
131 | if (r < 0) | |
132 | return r; | |
133 | ||
134 | if (end < start) | |
135 | return -EINVAL; | |
136 | ||
137 | nr = end - start + 1; | |
138 | } else { | |
139 | r = parse_uid(s, &start); | |
140 | if (r < 0) | |
141 | return r; | |
142 | ||
143 | nr = 1; | |
144 | } | |
145 | ||
146 | return uid_range_add(p, n, start, nr); | |
147 | } | |
148 | ||
149 | int uid_range_next_lower(const UidRange *p, unsigned n, uid_t *uid) { | |
fed1e721 | 150 | uid_t closest = UID_INVALID, candidate; |
8530dc44 LP |
151 | unsigned i; |
152 | ||
153 | assert(p); | |
154 | assert(uid); | |
155 | ||
156 | candidate = *uid - 1; | |
157 | ||
158 | for (i = 0; i < n; i++) { | |
159 | uid_t begin, end; | |
160 | ||
161 | begin = p[i].start; | |
162 | end = p[i].start + p[i].nr - 1; | |
163 | ||
164 | if (candidate >= begin && candidate <= end) { | |
165 | *uid = candidate; | |
166 | return 1; | |
167 | } | |
168 | ||
169 | if (end < candidate) | |
170 | closest = end; | |
171 | } | |
172 | ||
fed1e721 | 173 | if (closest == UID_INVALID) |
8530dc44 LP |
174 | return -EBUSY; |
175 | ||
176 | *uid = closest; | |
177 | return 1; | |
178 | } | |
179 | ||
180 | bool uid_range_contains(const UidRange *p, unsigned n, uid_t uid) { | |
181 | unsigned i; | |
182 | ||
183 | assert(p); | |
184 | assert(uid); | |
185 | ||
186 | for (i = 0; i < n; i++) | |
187 | if (uid >= p[i].start && uid < p[i].start + p[i].nr) | |
188 | return true; | |
189 | ||
190 | return false; | |
191 | } |