Add mkstemp() for those poor souls without it.

mkstemp.c

@@ -0,0 +1,202 @@
+/*	$OpenBSD: mktemp.c,v 1.19 2005/08/08 08:05:36 espie Exp $	*/
+
+/*
+ * Copyright (c) 2000, 2001, 2005 Todd C. Miller <Todd.Miller@courtesan.com>
+ * Copyright (c) 1987, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#if defined(TIME_WITH_SYS_TIME) || defined(HAVE_SYS_TIME_H)
+# include <sys/time.h>
+#endif
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+# include <stdlib.h>
+#endif /* HAVE_STDLIB_H */
+#include <ctype.h>
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+
+#include "sudo.h"
+
+#ifndef lint
+static const char rcsid[] = "$Sudo$";
+#endif /* not lint */
+
+static unsigned int get_random __P((void));
+static void seed_random __P((void));
+
+int
+mkstemp(path)
+	char *path;
+{
+	char *start, *trv;
+	struct stat sbuf;
+	int fd, rval;
+	pid_t pid;
+	char *alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+
+	if (*path == '\0') {
+		errno = EINVAL;
+		return (-1);		/* zero length path */
+	}
+	pid = getpid();
+	for (trv = path; *trv; ++trv)
+		;
+	--trv;
+	while (trv >= path && *trv == 'X' && pid != 0) {
+		*trv-- = (pid % 10) + '0';
+		pid /= 10;
+	}
+	while (trv >= path && *trv == 'X') {
+		char c;
+
+		/* assumes pid_t is at least 16 bits */
+		pid = (get_random() & 0xffff) % (26 + 26);
+		c = alphabet[pid];
+		*trv-- = c;
+	}
+	start = trv + 1;
+
+	/*
+	 * check the target directory; if you have six X's and it
+	 * doesn't exist this runs for a *very* long time.
+	 */
+	for (;; --trv) {
+		if (trv <= path)
+			break;
+		if (*trv == '/') {
+			*trv = '\0';
+			rval = stat(path, &sbuf);
+			*trv = '/';
+			if (rval != 0)
+				return (-1);
+			if (!S_ISDIR(sbuf.st_mode)) {
+				errno = ENOTDIR;
+				return (-1);
+			}
+			break;
+		}
+	}
+
+	for (;;) {
+		if ((fd = open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0)
+			return (fd);
+		if (errno != EEXIST)
+			return (-1);
+
+		/* tricky little algorithm for backward compatibility */
+		for (trv = start;;) {
+			if (!*trv)
+				return (-1);
+			if (*trv == 'Z')
+				*trv++ = 'a';
+			else {
+				if (isdigit((unsigned char)(*trv)))
+					*trv = 'a';
+				else if (*trv == 'z')	/* wrap from z to A */
+					*trv = 'A';
+				else {
+#ifdef HAVE_EBCDIC
+					switch(*trv) {
+					case 'i':
+						*trv = 'j';
+						break;
+					case 'r':
+						*trv = 's';
+						break;
+					case 'I':
+						*trv = 'J';
+						break;
+					case 'R':
+						*trv = 'S';
+						break;
+					default:
+						++*trv;
+						break;
+					}
+#else
+					++*trv;
+#endif
+				}
+				break;
+			}
+		}
+	}
+	/*NOTREACHED*/
+}
+
+#ifdef HAVE_RANDOM
+# define RAND		random
+# define SRAND		srandom
+# define SEED_T		unsigned int
+#else
+# ifdef HAVE_LRAND48
+#  define RAND		lrand48
+#  define SRAND		srand48
+#  define SEED_T	long
+# else
+#  define RAND		rand
+#  define SRAND		srand
+#  define SEED_T	unsigned int
+# endif
+#endif
+
+static void
+seed_random()
+{
+	SEED_T seed;
+	struct timespec ts;
+
+	/*
+	 * Seed from time of day and process id multiplied by small primes.
+	 */
+	(void) gettime(&ts);
+	seed = (ts.tv_sec % 10000) * 523 + ts.tv_nsec / 1000 * 13 +
+	    (getpid() % 1000) * 983;
+	SRAND(seed);
+}
+
+static unsigned int
+get_random()
+{
+	static int initialized;
+
+	if (!initialized) {
+		seed_random();
+		initialized = 1;
+	}
+
+	return(RAND() & 0xffffffff);
+}