source: vis_dev/glu-2.3/src/util/tmpfile.c@ 104

Last change on this file since 104 was 13, checked in by cecile, 15 years ago

library glu 2.3
File size: 3.3 KB
Line 
1/*
2 * Revision Control Information
3 *
4 * $Id: tmpfile.c,v 1.12 2009/01/05 21:04:04 fabio Exp $
5 *
6 */
7
8/*
9 * util_tmpfile -- open an unnamed temporary file
10 *
11 * Many compilers/systems do not have this, or have buggy versions.
12 *
13 */
14
15/* LINTLIBRARY */
16
17/* util_tempnam and check_directory are from
18 Jonathan I. Kamens <jik@pit-manager.mit.edu> */
19
20/* modified slightly by Ellen Sentovich ellen@ic.berkeley.edu */
21
22#include <sys/types.h>
23#if HAVE_SYS_STAT_H
24# include <sys/stat.h>
25#endif
26#if HAVE_SYS_FILE_H
27# include <sys/file.h>
28#endif
29
30#include "util.h"
31
32static char check_directory(char const *dir)
33{
34 struct stat statbuf;
35
36 if (! dir)
37 return 0;
38 else if (stat(dir, &statbuf) < 0)
39 return 0;
40 else if (S_ISDIR(statbuf.st_mode))
41 return 0;
42 else if (access(dir, W_OK | X_OK) < 0)
43 return 0;
44 else
45 return 1;
46}
47
48/* function for creating temporary filenames */
49char *util_tempnam(char const *dir, char const *pfx)
50{
51 extern char *getenv(const char *);
52 char const *tmpdir = NULL, *env;
53 char *filename;
54 static char unique_letters[4] = "AAA";
55 char addslash = 0;
56
57 /*
58 * If a directory is passed in, verify that it exists and is a
59 * directory and is writeable by this process. If no directory
60 * is passed in, or if the directory that is passed in does not
61 * exist, check the environment variable TMPDIR. If it isn't
62 * set, check the predefined constant P_tmpdir. If that isn't
63 * set, use "/tmp/".
64 */
65
66 if ((env = getenv ("TMPDIR")) && check_directory(env))
67 tmpdir = env;
68 else if (dir && check_directory(dir))
69 tmpdir = dir;
70#ifdef P_tmpdir
71 else if (check_directory(P_tmpdir))
72 tmpdir = P_tmpdir;
73#endif
74 else
75 tmpdir = "/tmp/";
76
77 /*
78 * OK, now that we've got a directory, figure out whether or not
79 * there's a slash at the end of it.
80 */
81 if (tmpdir[strlen(tmpdir) - 1] != '/')
82 addslash = 1;
83
84 /*
85 * Now figure out the set of unique letters.
86 */
87 unique_letters[0]++;
88 if (unique_letters[0] > 'Z') {
89 unique_letters[0] = 'A';
90 unique_letters[1]++;
91 if (unique_letters[1] > 'Z') {
92 unique_letters[1] = 'A';
93 unique_letters[2]++;
94 if (unique_letters[2] > 'Z') {
95 unique_letters[2]++;
96 }
97 }
98 }
99
100 /*
101 * Allocate a string of sufficient length.
102 */
103 if (pfx) {
104 filename = (char *) malloc(strlen(tmpdir) + addslash + strlen(pfx) + 10
105);
106 } else {
107 filename = (char *) malloc(strlen(tmpdir) + addslash + 10);
108 }
109
110 /*
111 * And create the string.
112 */
113 (void) sprintf(filename, "%s%s%s%sa%05d", tmpdir, addslash ? "/" : "",
114 pfx ? pfx : "", unique_letters, (int)getpid());
115
116 return filename;
117}
118
119
120#ifdef UNIX
121
122FILE *
123util_tmpfile(void)
124{
125 FILE *fp;
126 char *filename;
127
128 filename = util_tempnam(NIL(char), "VIS");
129 if ((fp = fopen(filename, "w+")) == NULL) {
130 FREE(filename);
131 return NULL;
132 }
133 (void) unlink(filename);
134 FREE(filename);
135 return fp;
136}
137
138#else
139
140FILE *
141util_tmpfile(void)
142{
143 FILE *fp;
144
145 if ((fp = fopen("utiltmp", "w+")) == NULL) {
146 return NULL;
147 }
148 (void) unlink("utiltmp");
149 return fp;
150}
151
152#endif
Note: See TracBrowser for help on using the repository browser.