Add some missing libc functions: setenv, unsetenv, strdup.

--HG-- rename : lang/cem/libcc.ansi/stdlib/getenv.c => lang/cem/libcc.ansi/stdlib/setenv.c rename : lang/cem/libcc.ansi/string/strlen.c => lang/cem/libcc.ansi/string/strdup.c extra : source : 64d6e6eec18d76bf8f3947ec5d171db94acdb282
2013-05-29 21:41:58 +01:00
parent f522aba4af
commit d273497077
7 changed files with 162 additions and 28 deletions
--- a/lang/cem/libcc.ansi/stdlib/setenv.c
+++ b/lang/cem/libcc.ansi/stdlib/setenv.c
@@ -0,0 +1,87 @@
+/*
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
+ */
+/* $Id$ */
+
+#include <stdlib.h>
+#include <string.h>
+
+extern char* _findenv(const char* name, int* offset);
+extern char **environ;
+
+/*
+ * setenv(name,value,rewrite)
+ *	Set the value of the environmental variable "name" to be
+ *	"value".  If rewrite is set, replace any current value.
+ */
+int setenv(register const char* name, register const char* value, int rewrite)
+{
+    static int  alloced = 0;        /* 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 = 0;
+        register char   **P;
+
+		if (environ)
+			for (P = environ;*P;++P,++cnt);
+        if (alloced) {          /* just increase size */
+            environ = (char **)realloc((char *)environ,
+                (unsigned)(sizeof(char *) * (cnt + 2)));
+            if (!environ)
+                return(-1);
+        }
+        else {              /* get new space */
+            alloced = 1;        /* copy old entries into it */
+            P = (char **)malloc((unsigned)(sizeof(char *) *
+                (cnt + 2)));
+            if (!P)
+                return(-1);
+            if (environ)
+				bcopy(environ,P,cnt * sizeof(char *));
+            environ = P;
+        }
+        environ[cnt + 1] = NULL;
+        offset = cnt;
+    }
+    for (C = name;*C && *C != '=';++C); /* no `=' in name */
+    if (!(environ[offset] =         /* name + `=' + value */
+        malloc((unsigned)((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".
+ */
+int
+unsetenv(const char* name)
+{
+    register char   **P;
+    int offset;
+
+    while (_findenv(name,&offset))      /* if set multiple times */
+        for (P = &environ[offset];;++P)
+            if (!(*P = *(P + 1)))
+                break;
+
+    return 0;
+}
+