1 /*
2 * Copyright © 2015 Collabora, Ltd.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the
13 * next paragraph) shall be included in all copies or substantial
14 * portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
20 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
21 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE.
24 */
25
26 #include "config.h"
27
28 #include <stdio.h>
29 #include <errno.h>
30 #include <time.h>
31 #include <sys/types.h>
32 #include <sys/stat.h>
33 #include <fcntl.h>
34 #include <stdlib.h>
35
36 #include "file-util.h"
37
38 static int
current_time_str(char * str,size_t len,const char * fmt)39 current_time_str(char *str, size_t len, const char *fmt)
40 {
41 time_t t;
42 struct tm *t_local;
43 int ret;
44
45 t = time(NULL);
46 t_local = localtime(&t);
47 if (!t_local) {
48 errno = ETIME;
49 return -1;
50 }
51
52 ret = strftime(str, len, fmt, t_local);
53 if (ret == 0) {
54 errno = ETIME;
55 return -1;
56 }
57
58 return ret;
59 }
60
61 static int
create_file_excl(const char * fname)62 create_file_excl(const char *fname)
63 {
64 return open(fname, O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 00666);
65 }
66
67 /** Create a unique file with date and time in the name
68 *
69 * \param path File path
70 * \param prefix File name prefix.
71 * \param suffix File name suffix.
72 * \param[out] name_out Buffer for the resulting file name.
73 * \param name_len Number of bytes usable in name_out.
74 * \return stdio FILE pointer, or NULL on failure.
75 *
76 * Create and open a new file with the name concatenated from
77 * path/prefix, date and time, and suffix. If a file with this name
78 * already exists, an counter number is added to the end of the
79 * date and time sub-string. The counter is increased until a free file
80 * name is found.
81 *
82 * Once creating the file succeeds, the name of the file is in name_out.
83 * On failure, the contents of name_out are undefined and errno is set.
84 */
85 FILE *
file_create_dated(const char * path,const char * prefix,const char * suffix,char * name_out,size_t name_len)86 file_create_dated(const char *path, const char *prefix, const char *suffix,
87 char *name_out, size_t name_len)
88 {
89 char timestr[128];
90 int ret;
91 int fd;
92 int cnt = 0;
93 int with_path;
94
95 with_path = path && path[0];
96
97 if (current_time_str(timestr, sizeof(timestr), "%F_%H-%M-%S") < 0)
98 return NULL;
99
100 ret = snprintf(name_out, name_len, "%s%s%s%s%s",
101 with_path ? path : "", with_path ? "/" : "",
102 prefix, timestr, suffix);
103 if (ret < 0 || (size_t)ret >= name_len) {
104 errno = ENOBUFS;
105 return NULL;
106 }
107
108 fd = create_file_excl(name_out);
109
110 while (fd == -1 && errno == EEXIST) {
111 cnt++;
112
113 ret = snprintf(name_out, name_len, "%s%s%s%s-%d%s",
114 with_path ? path : "", with_path ? "/" : "",
115 prefix, timestr, cnt, suffix);
116 if (ret < 0 || (size_t)ret >= name_len) {
117 errno = ENOBUFS;
118 return NULL;
119 }
120
121 fd = create_file_excl(name_out);
122 }
123
124 if (fd == -1)
125 return NULL;
126
127 return fdopen(fd, "w");
128 }
129
130 char *
file_name_with_datadir(const char * filename)131 file_name_with_datadir(const char *filename)
132 {
133 const char *base = getenv("WESTON_DATA_DIR");
134 char *out;
135 int len;
136
137 if (base)
138 len = asprintf(&out, "%s/%s", base, filename);
139 else
140 len = asprintf(&out, "%s/weston/%s", DATADIR, filename);
141
142 if (len == -1)
143 return NULL;
144
145 return out;
146 }
147