Fix rsync exit handling in create mode.
[dss.git] / str.c
1 /*
2 * Copyright (C) 2004-2010 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6 #include <string.h>
7 #include <stdlib.h>
8 #include <stdio.h>
9 #include <stdarg.h>
10 #include <assert.h>
11 #include <limits.h>
12 #include <errno.h>
13 #include <pwd.h>
14 #include <sys/types.h>
15 #include <unistd.h>
16
17
18 #include "gcc-compat.h"
19 #include "log.h"
20 #include "err.h"
21 #include "str.h"
22
23 /**
24 * dss' version of realloc().
25 *
26 * \param p Pointer to the memory block, may be \p NULL.
27 * \param size The desired new size.
28 *
29 * A wrapper for realloc(3). It calls \p exit(\p EXIT_FAILURE) on errors,
30 * i.e. there is no need to check the return value in the caller.
31 *
32 * \return A pointer to the newly allocated memory, which is suitably aligned
33 * for any kind of variable and may be different from \a p.
34 *
35 * \sa realloc(3).
36 */
37 __must_check __malloc void *dss_realloc(void *p, size_t size)
38 {
39 /*
40 * No need to check for NULL pointers: If p is NULL, the call
41 * to realloc is equivalent to malloc(size)
42 */
43 assert(size);
44 if (!(p = realloc(p, size))) {
45 DSS_EMERG_LOG(("realloc failed (size = %zu), aborting\n",
46 size));
47 exit(EXIT_FAILURE);
48 }
49 return p;
50 }
51
52 /**
53 * dss' version of malloc().
54 *
55 * \param size The desired new size.
56 *
57 * A wrapper for malloc(3) which exits on errors.
58 *
59 * \return A pointer to the allocated memory, which is suitably aligned for any
60 * kind of variable.
61 *
62 * \sa malloc(3).
63 */
64 __must_check __malloc void *dss_malloc(size_t size)
65 {
66 void *p;
67 assert(size);
68 p = malloc(size);
69
70 if (!p) {
71 DSS_EMERG_LOG(("malloc failed (size = %zu), aborting\n",
72 size));
73 exit(EXIT_FAILURE);
74 }
75 return p;
76 }
77
78 /**
79 * dss' version of calloc().
80 *
81 * \param size The desired new size.
82 *
83 * A wrapper for calloc(3) which exits on errors.
84 *
85 * \return A pointer to the allocated and zeroed-out memory, which is suitably
86 * aligned for any kind of variable.
87 *
88 * \sa calloc(3)
89 */
90 __must_check __malloc void *dss_calloc(size_t size)
91 {
92 void *ret = dss_malloc(size);
93
94 memset(ret, 0, size);
95 return ret;
96 }
97
98 /**
99 * dss' version of strdup().
100 *
101 * \param s The string to be duplicated.
102 *
103 * A wrapper for strdup(3). It calls \p exit(EXIT_FAILURE) on errors, i.e.
104 * there is no need to check the return value in the caller.
105 *
106 * \return A pointer to the duplicated string. If \p s was the NULL pointer,
107 * an pointer to an empty string is returned.
108 *
109 * \sa strdup(3)
110 */
111
112 __must_check __malloc char *dss_strdup(const char *s)
113 {
114 char *ret;
115
116 if ((ret = strdup(s? s: "")))
117 return ret;
118 DSS_EMERG_LOG(("strdup failed, aborting\n"));
119 exit(EXIT_FAILURE);
120 }
121
122 /**
123 * Allocate a sufficiently large string and print into it.
124 *
125 * \param fmt A usual format string.
126 *
127 * Produce output according to \p fmt. No artificial bound on the length of the
128 * resulting string is imposed.
129 *
130 * \return This function either returns a pointer to a string that must be
131 * freed by the caller or aborts without returning.
132 *
133 * \sa printf(3).
134 */
135 __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
136 {
137 char *msg;
138 size_t size = 100;
139
140 msg = dss_malloc(size);
141 while (1) {
142 int n;
143 va_list ap;
144
145 /* Try to print in the allocated space. */
146 va_start(ap, fmt);
147 n = vsnprintf(msg, size, fmt, ap);
148 va_end(ap);
149 /* If that worked, return the string. */
150 if (n < size)
151 return msg;
152 /* Else try again with more space. */
153 size = n + 1; /* precisely what is needed */
154 msg = dss_realloc(msg, size);
155 }
156 }
157
158 /**
159 * Get the home directory of the current user.
160 *
161 * \return A dynamically allocated string that must be freed by the caller. If
162 * the home directory could not be found, this function returns "/tmp".
163 */
164 __must_check __malloc char *get_homedir(void)
165 {
166 struct passwd *pw = getpwuid(getuid());
167 return dss_strdup(pw? pw->pw_dir : "/tmp");
168 }
169
170 /**
171 * Convert a string to a 64-bit signed integer value.
172 *
173 * \param str The string to be converted.
174 * \param value Result pointer.
175 *
176 * \return Standard.
177 *
178 * \sa strtol(3), atoi(3).
179 */
180 int dss_atoi64(const char *str, int64_t *value)
181 {
182 char *endptr;
183 long long tmp;
184
185 errno = 0; /* To distinguish success/failure after call */
186 tmp = strtoll(str, &endptr, 10);
187 if (errno == ERANGE && (tmp == LLONG_MAX || tmp == LLONG_MIN))
188 return -E_ATOI_OVERFLOW;
189 if (errno != 0 && tmp == 0) /* other error */
190 return -E_STRTOLL;
191 if (endptr == str)
192 return -E_ATOI_NO_DIGITS;
193 if (*endptr != '\0') /* Further characters after number */
194 return -E_ATOI_JUNK_AT_END;
195 *value = tmp;
196 return 1;
197 }
198
199 /**
200 * Get the logname of the current user.
201 *
202 * \return A dynamically allocated string that must be freed by the caller. On
203 * errors, the string "unknown user" is returned, i.e. this function never
204 * returns \p NULL.
205 *
206 * \sa getpwuid(3).
207 */
208 __must_check __malloc char *dss_logname(void)
209 {
210 struct passwd *pw = getpwuid(getuid());
211 return dss_strdup(pw? pw->pw_name : "unknown_user");
212 }
213
214 /**
215 * Split string and return pointers to its parts.
216 *
217 * \param args The string to be split.
218 * \param argv_ptr Pointer to the list of substrings.
219 * \param delim Delimiter.
220 *
221 * This function modifies \a args by replacing each occurrence of \a delim by
222 * zero. A \p NULL-terminated array of pointers to char* is allocated dynamically
223 * and these pointers are initialized to point to the broken-up substrings
224 * within \a args. A pointer to this array is returned via \a argv_ptr.
225 *
226 * \return The number of substrings found in \a args.
227 */
228 unsigned split_args(char *args, char *** const argv_ptr, const char *delim)
229 {
230 char *p;
231 char **argv;
232 size_t n = 0, i, j;
233
234 p = args + strspn(args, delim);
235 for (;;) {
236 i = strcspn(p, delim);
237 if (!i)
238 break;
239 p += i;
240 n++;
241 p += strspn(p, delim);
242 }
243 *argv_ptr = dss_malloc((n + 1) * sizeof(char *));
244 argv = *argv_ptr;
245 i = 0;
246 p = args + strspn(args, delim);
247 while (p) {
248 argv[i] = p;
249 j = strcspn(p, delim);
250 if (!j)
251 break;
252 p += strcspn(p, delim);
253 if (*p) {
254 *p = '\0';
255 p++;
256 p += strspn(p, delim);
257 }
258 i++;
259 }
260 argv[n] = NULL;
261 return n;
262 }