BSD 4.4 Lite Lib Sources

1 files changed, 116 insertions, 0 deletions

diff --git a/lib/libc/stdlib/setenv.c b/lib/libc/stdlib/setenv.c
new file mode 100644
index 0000000..b36d673
--- /dev/null
+++ b/lib/libc/stdlib/setenv.c
@@ -0,0 +1,116 @@
+/*
+ * 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.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)setenv.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+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.
+ */
+setenv(name, value, rewrite)
+	register const char *name;
+	register const char *value;
+	int rewrite;
+{
+	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 = malloc((size_t)(sizeof(char *) * (cnt + 2)));
+			if (!p)
+				return (-1);
+			bcopy(environ, p, 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);
+}
+
+/*
+ * unsetenv(name) --
+ *	Delete environmental variable "name".
+ */
+void
+unsetenv(name)
+	const char *name;
+{
+	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;
+}