0b929688a2496d5a5f57c8a9e5590b17dd5d697a
[adu.git] / string.c
1 /*
2 * Copyright (C) 2004-2008 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file string.c Memory allocation and string handling functions. */
8
9 #include "adu.h"
10 #include "string.h"
11 #include <string.h>
12 #include "error.h"
13
14 /**
15 * Paraslash's version of realloc().
16 *
17 * \param p Pointer to the memory block, may be \p NULL.
18 * \param size The desired new size.
19 *
20 * A wrapper for realloc(3). It calls \p exit(\p EXIT_FAILURE) on errors,
21 * i.e. there is no need to check the return value in the caller.
22 *
23 * \return A pointer to the newly allocated memory, which is suitably aligned
24 * for any kind of variable and may be different from \a p.
25 *
26 * \sa realloc(3).
27 */
28 __must_check __malloc void *adu_realloc(void *p, size_t size)
29 {
30 /*
31 * No need to check for NULL pointers: If p is NULL, the call
32 * to realloc is equivalent to malloc(size)
33 */
34 assert(size);
35 if (!(p = realloc(p, size))) {
36 EMERG_LOG("realloc failed (size = %zu), aborting\n",
37 size);
38 exit(EXIT_FAILURE);
39 }
40 return p;
41 }
42
43 /**
44 * Paraslash's version of malloc().
45 *
46 * \param size The desired new size.
47 *
48 * A wrapper for malloc(3) which exits on errors.
49 *
50 * \return A pointer to the allocated memory, which is suitably aligned for any
51 * kind of variable.
52 *
53 * \sa malloc(3).
54 */
55 __must_check __malloc void *adu_malloc(size_t size)
56 {
57 assert(size);
58 void *p = malloc(size);
59
60 if (!p) {
61 EMERG_LOG("malloc failed (size = %zu), aborting\n",
62 size);
63 exit(EXIT_FAILURE);
64 }
65 return p;
66 }
67
68 /**
69 * Paraslash's version of calloc().
70 *
71 * \param size The desired new size.
72 *
73 * A wrapper for calloc(3) which exits on errors.
74 *
75 * \return A pointer to the allocated and zeroed-out memory, which is suitably
76 * aligned for any kind of variable.
77 *
78 * \sa calloc(3)
79 */
80 __must_check __malloc void *adu_calloc(size_t size)
81 {
82 void *ret = adu_malloc(size);
83
84 memset(ret, 0, size);
85 return ret;
86 }
87
88 /**
89 * Paraslash's version of strdup().
90 *
91 * \param s The string to be duplicated.
92 *
93 * A wrapper for strdup(3). It calls \p exit(EXIT_FAILURE) on errors, i.e.
94 * there is no need to check the return value in the caller.
95 *
96 * \return A pointer to the duplicated string. If \p s was the NULL pointer,
97 * an pointer to an empty string is returned.
98 *
99 * \sa strdup(3)
100 */
101 __must_check __malloc char *adu_strdup(const char *s)
102 {
103 char *ret;
104
105 if ((ret = strdup(s? s: "")))
106 return ret;
107 EMERG_LOG("strdup failed, aborting\n");
108 exit(EXIT_FAILURE);
109 }
110
111 /**
112 * Allocate a sufficiently large string and print into it.
113 *
114 * \param fmt A usual format string.
115 *
116 * Produce output according to \p fmt. No artificial bound on the length of the
117 * resulting string is imposed.
118 *
119 * \return This function either returns a pointer to a string that must be
120 * freed by the caller or aborts without returning.
121 *
122 * \sa printf(3).
123 */
124 __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
125 {
126 char *msg;
127
128 VSPRINTF(fmt, msg);
129 return msg;
130 }
131
132 /**
133 * adu's version of strcat().
134 *
135 * \param a String to be appended to.
136 * \param b String to append.
137 *
138 * Append \p b to \p a.
139 *
140 * \return If \a a is \p NULL, return a pointer to a copy of \a b, i.e.
141 * para_strcat(NULL, b) is equivalent to para_strdup(b). If \a b is \p NULL,
142 * return \a a without making a copy of \a a. Otherwise, construct the
143 * concatenation \a c, free \a a (but not \a b) and return \a c.
144 *
145 * \sa strcat(3).
146 */
147 __must_check __malloc char *adu_strcat(char *a, const char *b)
148 {
149 char *tmp;
150
151 if (!a)
152 return adu_strdup(b);
153 if (!b)
154 return a;
155 tmp = make_message("%s%s", a, b);
156 free(a);
157 return tmp;
158 }
159
160 /** \cond LLONG_MAX and LLONG_LIN might not be defined. */
161 #ifndef LLONG_MAX
162 #define LLONG_MAX (1 << (sizeof(long) - 1))
163 #endif
164 #ifndef LLONG_MIN
165 #define LLONG_MIN (-LLONG_MAX - 1LL)
166 #endif
167 /** \endcond */
168
169 /**
170 * Convert a string to a 64-bit signed integer value.
171 *
172 * \param str The string to be converted.
173 * \param value Result pointer.
174 *
175 * \return Standard.
176 *
177 * \sa strtol(3), atoi(3).
178 */
179 __must_check int atoi64(const char *str, int64_t *result)
180 {
181 char *endptr;
182 long long tmp;
183
184 errno = 0; /* To distinguish success/failure after call */
185 tmp = strtoll(str, &endptr, 10);
186 if (errno == ERANGE && (tmp == LLONG_MAX || tmp == LLONG_MIN))
187 return -E_ATOI_OVERFLOW;
188 if (errno != 0 && tmp == 0) /* other error */
189 return -E_STRTOLL;
190 if (endptr == str)
191 return -E_ATOI_NO_DIGITS;
192 if (*endptr != '\0') /* Further characters after number */
193 return -E_ATOI_JUNK_AT_END;
194 *result = tmp;
195 return 1;
196 }
197
198 /**
199 * Split string and return pointers to its parts.
200 *
201 * \param args The string to be split.
202 * \param argv_ptr Pointer to the list of substrings.
203 * \param delim Delimiter.
204 *
205 * This function modifies \a args by replacing each occurance of \a delim by
206 * zero. A \p NULL-terminated array of pointers to char* is allocated dynamically
207 * and these pointers are initialized to point to the broken-up substrings
208 * within \a args. A pointer to this array is returned via \a argv_ptr.
209 *
210 * \return The number of substrings found in \a args.
211 */
212 __must_check unsigned split_args(char *args, char *** const argv_ptr, const char *delim)
213 {
214 char *p = args;
215 char **argv;
216 size_t n = 0, i, j;
217
218 p = args + strspn(args, delim);
219 for (;;) {
220 i = strcspn(p, delim);
221 if (!i)
222 break;
223 p += i;
224 n++;
225 p += strspn(p, delim);
226 }
227 *argv_ptr = adu_malloc((n + 1) * sizeof(char *));
228 argv = *argv_ptr;
229 i = 0;
230 p = args + strspn(args, delim);
231 while (p) {
232 argv[i] = p;
233 j = strcspn(p, delim);
234 if (!j)
235 break;
236 p += strcspn(p, delim);
237 if (*p) {
238 *p = '\0';
239 p++;
240 p += strspn(p, delim);
241 }
242 i++;
243 }
244 argv[n] = NULL;
245 return n;
246 }
247
248 static int check_uid_arg(const char *arg, uint32_t *uid)
249 {
250 const uint32_t max = ~0U;
251 /*
252 * we need an 64-bit int for string -> uid conversion because strtoll()
253 * returns a signed value.
254 */
255 int64_t val;
256 int ret = atoi64(arg, &val);
257
258 if (ret < 0)
259 return ret;
260 if (val < 0 || val > max)
261 return -ERRNO_TO_ERROR(EINVAL);
262 *uid = val;
263 return 1;
264 }
265
266 int parse_uid_range(const char *orig_arg, struct uid_range *ur)
267 {
268 int ret;
269 char *arg = adu_strdup(orig_arg), *p = strchr(arg, '-');
270
271 if (!p || p == arg) { /* -42 or 42 */
272 ret = check_uid_arg(p? p + 1 : arg, &ur->high);
273 if (ret < 0)
274 goto out;
275 ur->low = p? 0 : ur->high;
276 ret = 1;
277 goto out;
278 }
279 /* 42- or 42-4711 */
280 *p = '\0';
281 p++;
282 ret = check_uid_arg(arg, &ur->low);
283 if (ret < 0)
284 goto out;
285 ur->high = ~0U;
286 if (*p) { /* 42-4711 */
287 ret = check_uid_arg(p, &ur->high);
288 if (ret < 0)
289 goto out;
290 }
291 if (ur->low > ur->high)
292 ret = -ERRNO_TO_ERROR(EINVAL);
293 out:
294 if (ret < 0)
295 ERROR_LOG("bad uid option: %s\n", orig_arg);
296 else
297 INFO_LOG("admissible uid range: %u - %u\n", ur->low,
298 ur->high);
299 free(arg);
300 return ret;
301 }
302
303 int parse_uid_arg(const char *orig_arg, struct uid_range **ur)
304 {
305 char *arg, **argv;
306 unsigned n;
307 int i, ret = 1;
308
309 if (!orig_arg)
310 return 0;
311 arg = adu_strdup(orig_arg);
312 n = split_args(arg, &argv, ",");
313 if (!n)
314 return -E_SYNTAX;
315 *ur = adu_malloc((n + 1) * sizeof(struct uid_range));
316 for (i = 0; i < n; i++) {
317 ret = parse_uid_range(argv[i], *ur + i);
318 if (ret < 0)
319 break;
320 }
321 free(arg);
322 if (ret < 0) {
323 free(*ur);
324 *ur = NULL;
325 }
326 /* an empty range indicates the end of the list */
327 (*ur)[n].low = 1;
328 (*ur)[n].high = 0;
329 return n;
330 }