getcwd did not include the alloc-space-as-needed-on-NULL-buffer

feature which busybox needed.  So I added it.

diff --git a/libc/unistd/getcwd.c b/libc/unistd/getcwd.c
index 12eda45..c0be5c3 100644 (file)
--- a/libc/unistd/getcwd.c
+++ b/libc/unistd/getcwd.c
@@ -1,13 +1,10 @@
-
+#include <stdlib.h>
 #include <errno.h>
 #include <sys/stat.h>
 #include <dirent.h>
 #include <string.h>
-/*
- * These functions find the absolute path to the current working directory.
- *
- * They don't use malloc or large amounts of stack space.
- */
+
+/* These functions find the absolute path to the current working directory.  */
 
 static char *recurser();               /* Routine to go up tree */
 static char *search_dir();             /* Routine to find the step back down */
@@ -19,21 +16,28 @@ static ino_t root_ino;
 
 static struct stat st;
 
-char *getcwd(buf, size)
-char *buf;
-int size;
+char *getcwd( char *buf, int size)
 {
-       path_buf = buf;
        path_size = size;
 
        if (size < 3) {
                errno = ERANGE;
-               return 0;
+               return NULL;
        }
+
+       if (buf != NULL)
+           path_buf = buf;
+       else
+       {
+           path_buf = malloc (size);
+           if (path_buf == NULL)
+               return NULL;
+       }
+
        strcpy(path_buf, ".");
 
        if (stat("/", &st) < 0)
-               return 0;
+               return NULL;
 
        root_dev = st.st_dev;
        root_ino = st.st_ino;