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 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * tmpfile - return a pointer to an update file that can be 34 * used for scratch. The file will automatically 35 * go away if the program using it terminates. 36 */ 37 38 #include "lint.h" 39 #include "mtlib.h" 40 #include <sys/types.h> 41 #include <unistd.h> 42 #include <stdio.h> 43 #include <string.h> 44 #include <stdlib.h> 45 #include <thread.h> 46 #include <synch.h> 47 #include <sys/stat.h> 48 49 static char seed[] = { 'a', 'a', 'a', '\0' }; 50 static mutex_t seed_lk = DEFAULTMUTEX; 51 52 #define XS "\bXXXXXX" /* a '\b' character is prepended to this */ 53 /* string to avoid conflicts with names */ 54 /* generated by tmpnam() */ 55 /*ARGSUSED*/ 56 static FILE * 57 _common(boolean_t large_file) 58 { 59 char tfname[L_tmpnam]; 60 FILE *p; 61 char *q; 62 int mkret; 63 mode_t current_umask; 64 65 (void) strcpy(tfname, P_tmpdir); 66 lmutex_lock(&seed_lk); 67 (void) strcat(tfname, seed); 68 (void) strcat(tfname, XS); 69 70 q = seed; 71 while (*q == 'z') 72 *q++ = 'a'; 73 if (*q != '\0') 74 ++*q; 75 lmutex_unlock(&seed_lk); 76 77 #if !defined(_LP64) 78 if (large_file == B_TRUE) { 79 if ((mkret = mkstemp64(tfname)) == -1) 80 return (NULL); 81 } else 82 #endif 83 if ((mkret = mkstemp(tfname)) == -1) 84 return (NULL); 85 86 (void) unlink(tfname); 87 current_umask = umask(0777); 88 (void) umask(current_umask); 89 (void) fchmod(mkret, 0666 & ~current_umask); 90 if ((p = fdopen(mkret, "w+")) == NULL) { 91 (void) close(mkret); 92 return (NULL); 93 } 94 95 return (p); 96 } 97 98 #if !defined(_LP64) 99 FILE * 100 tmpfile64(void) 101 { 102 return (_common(B_TRUE)); 103 } 104 #endif /* _LP64 */ 105 106 /* 107 * This is a bit confusing -- some explanation is in order. 108 * 109 * When we're compiled 64-bit, there's no point in distinguishing 110 * a "large" file from a "small" file -- they're all "large". 111 * The argument we pass to '_common' is ignored -- we always call 112 * mkstemp which will just do the right thing for us. 113 */ 114 FILE * 115 tmpfile(void) 116 { 117 return (_common(B_FALSE)); 118 } 119