1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1988 AT&T */ 28 /* All Rights Reserved */ 29 30 /* 31 * tmpfile - return a pointer to an update file that can be 32 * used for scratch. The file will automatically 33 * go away if the program using it terminates. 34 */ 35 36 #include "lint.h" 37 #include "mtlib.h" 38 #include <sys/types.h> 39 #include <unistd.h> 40 #include <stdio.h> 41 #include <string.h> 42 #include <stdlib.h> 43 #include <thread.h> 44 #include <synch.h> 45 #include <sys/stat.h> 46 47 static char seed[] = { 'a', 'a', 'a', '\0' }; 48 static mutex_t seed_lk = DEFAULTMUTEX; 49 50 #define XS "\bXXXXXX" /* a '\b' character is prepended to this */ 51 /* string to avoid conflicts with names */ 52 /* generated by tmpnam() */ 53 static FILE * 54 _common(boolean_t large_file __unused) 55 { 56 char tfname[L_tmpnam]; 57 FILE *p; 58 char *q; 59 int mkret; 60 mode_t current_umask; 61 62 (void) strcpy(tfname, P_tmpdir); 63 lmutex_lock(&seed_lk); 64 (void) strcat(tfname, seed); 65 (void) strcat(tfname, XS); 66 67 q = seed; 68 while (*q == 'z') 69 *q++ = 'a'; 70 if (*q != '\0') 71 ++*q; 72 lmutex_unlock(&seed_lk); 73 74 #if !defined(_LP64) 75 if (large_file == B_TRUE) { 76 if ((mkret = mkstemp64(tfname)) == -1) 77 return (NULL); 78 } else 79 #endif 80 if ((mkret = mkstemp(tfname)) == -1) 81 return (NULL); 82 83 (void) unlink(tfname); 84 current_umask = umask(0777); 85 (void) umask(current_umask); 86 (void) fchmod(mkret, 0666 & ~current_umask); 87 if ((p = fdopen(mkret, "w+")) == NULL) { 88 (void) close(mkret); 89 return (NULL); 90 } 91 92 return (p); 93 } 94 95 #if !defined(_LP64) 96 FILE * 97 tmpfile64(void) 98 { 99 return (_common(B_TRUE)); 100 } 101 #endif /* _LP64 */ 102 103 /* 104 * This is a bit confusing -- some explanation is in order. 105 * 106 * When we're compiled 64-bit, there's no point in distinguishing 107 * a "large" file from a "small" file -- they're all "large". 108 * The argument we pass to '_common' is ignored -- we always call 109 * mkstemp which will just do the right thing for us. 110 */ 111 FILE * 112 tmpfile(void) 113 { 114 return (_common(B_FALSE)); 115 } 116