* configure.in: Check for presense of setenv(), unsetenv(), and

	getenv() from the C library.

* Makefile.in: New file: setenv.c --- provides routines for
	setting the environment.


git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@7266 dc483132-0cff-0310-8789-dd5450dbe970

src/lib/krb5/posix/ChangeLog

@@ -1,3 +1,11 @@
+Wed Jan  3 22:25:52 1996  Theodore Y. Ts'o  <tytso@dcl>
+
+	* configure.in: Check for presense of setenv(), unsetenv(), and
+		getenv() from the C library.
+
+	* Makefile.in: New file: setenv.c --- provides routines for
+		setting the environment.
+
 Tue Dec 19 17:29:21 1995  Theodore Y. Ts'o  <tytso@dcl>
 
 	* configure.in: Don't drag in syslog.c if vsyslog() is not

src/lib/krb5/posix/Makefile.in

@@ -7,7 +7,7 @@ CFLAGS = $(CCOPTS) $(DEFS)
 	$(CC) $(CFLAGS) -c $(srcdir)/$*.c
 @SHARED_RULE@
 
-OBJS = @LIBOBJS@
+OBJS = setenv.$(OBJEXT)	@LIBOBJS@
 
 all-unix:: shared $(OBJS)
 all-mac: $(OBJS)

src/lib/krb5/posix/configure.in

@@ -4,6 +4,7 @@ SubdirLibraryRule([${OBJS}])
 V5_SHARED_LIB_OBJS
 AC_CONST
 AC_HEADER_CHECK(paths.h,AC_DEFINE(HAS_PATHS_H))
+AC_HAVE_FUNCS(setenv unsetenv getenv)
 AC_REPLACE_FUNCS(vfprintf vsprintf strdup strcasecmp strerror memmove daemon getuid sscanf syslog)
 AC_FUNC_CHECK(setsid,AC_DEFINE(HAS_SETSID))
 V5_AC_OUTPUT_MAKEFILE

src/lib/krb5/posix/setenv.c

@@ -0,0 +1,180 @@
+/*
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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.
+ */
+
+/* based on @(#)setenv.c	8.1 (Berkeley) 6/4/93 */
+/* based on @(#)getenv.c	8.1 (Berkeley) 6/4/93 */
+
+#ifndef __STDC__
+#define const
+#endif
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef	__P
+#define __P(x)	()
+#endif
+static char *__findenv __P((const char *, int *)); 
+
+/*
+ * setenv --
+ *	Set the value of the environmental variable "name" to be
+ *	"value".  If rewrite is set, replace any current value.
+ */
+int
+krb5_setenv(name, value, rewrite)
+	register const char *name;
+	register const char *value;
+	int rewrite;
+{
+#if HAVE_SETENV
+    return (setenv(name, value, rewrite));
+#else
+	extern char **environ;
+	static int alloced;			/* if allocated space before */
+	register char *c;
+	int l_value, offset;
+
+	if (*value == '=')			/* no `=' in value */
+		++value;
+	l_value = strlen(value);
+	if ((c = __findenv(name, &offset))) {	/* find if already exists */
+		if (!rewrite)
+			return (0);
+		if (strlen(c) >= l_value) {	/* old larger; copy over */
+			while ((*c++ = *value++));
+			return (0);
+		}
+	} else {					/* create new slot */
+		register int cnt;
+		register char **p;
+
+		for (p = environ, cnt = 0; *p; ++p, ++cnt);
+		if (alloced) {			/* just increase size */
+			environ = (char **)realloc((char *)environ,
+			    (size_t)(sizeof(char *) * (cnt + 2)));
+			if (!environ)
+				return (-1);
+		}
+		else {				/* get new space */
+			alloced = 1;		/* copy old entries into it */
+			p = (char **)malloc((size_t)(sizeof(char *) * (cnt + 2)));
+			if (!p)
+				return (-1);
+			memcpy(p, environ, cnt * sizeof(char *));
+			environ = p;
+		}
+		environ[cnt + 1] = NULL;
+		offset = cnt;
+	}
+	for (c = (char *)name; *c && *c != '='; ++c);	/* no `=' in name */
+	if (!(environ[offset] =			/* name + `=' + value */
+	    malloc((size_t)((int)(c - name) + l_value + 2))))
+		return (-1);
+	for (c = environ[offset]; (*c = *name++) && *c != '='; ++c);
+	for (*c++ = '='; (*c++ = *value++););
+	return (0);
+#endif
+}
+
+/*
+ * unsetenv(name) --
+ *	Delete environmental variable "name".
+ */
+void
+krb5_unsetenv(name)
+	const char *name;
+{
+#if HAVE_UNSETENV
+    unsetenv(name);
+#else
+	extern char **environ;
+	register char **p;
+	int offset;
+
+	while (__findenv(name, &offset))	/* if set multiple times */
+		for (p = &environ[offset];; ++p)
+			if (!(*p = *(p + 1)))
+				break;
+#endif
+}
+
+/*
+ * getenv --
+ *	Returns ptr to value associated with name, if any, else NULL.
+ */
+char *
+krb5_getenv(name)
+	const char *name;
+{
+#if HAVE_GETENV
+    return (getenv(name));
+#else
+	int offset;
+
+	return (__findenv(name, &offset));
+#endif
+}
+
+#if (!HAVE_GETENV || !HAVE_SETENV || !HAVE_UNSETENV)
+/*
+ * __findenv --
+ *	Returns pointer to value associated with name, if any, else NULL.
+ *	Sets offset to be the offset of the name/value combination in the
+ *	environmental array, for use by setenv(3) and unsetenv(3).
+ *	Explicitly removes '=' in argument name.
+ */
+static char *
+__findenv(name, offset)
+	register const char *name;
+	int *offset;
+{
+	extern char **environ;
+	register int len;
+	register const char *np;
+	register char **p, *c;
+
+	if (name == NULL || environ == NULL)
+		return (NULL);
+	for (np = name; *np && *np != '='; ++np)
+		continue;
+	len = np - name;
+	for (p = environ; (c = *p) != NULL; ++p)
+		if (strncmp(c, name, len) == 0 && c[len] == '=') {
+			*offset = p - environ;
+			return (c + len + 1);
+		}
+	return (NULL);
+}
+#endif