auto import from //depot/cupcake/@135843
diff --git a/libc/unistd/opendir.c b/libc/unistd/opendir.c
new file mode 100644
index 0000000..afa3ea0
--- /dev/null
+++ b/libc/unistd/opendir.c
@@ -0,0 +1,267 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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 <unistd.h>
+#include <dirent.h>
+#include <memory.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <pthread.h>
+#include <errno.h>
+
+struct DIR
+{
+    int              _DIR_fd;
+    size_t           _DIR_avail;
+    struct dirent*   _DIR_next;
+    pthread_mutex_t  _DIR_lock;
+    struct dirent    _DIR_buff[15];
+};
+
+int dirfd(DIR* dirp)
+{
+    return dirp->_DIR_fd;
+}
+
+DIR*  opendir( const char*  dirpath )
+{
+    DIR*  dir = malloc(sizeof(DIR));
+
+    if (!dir)
+        goto Exit;
+
+    dir->_DIR_fd = open(dirpath, O_RDONLY|O_DIRECTORY);
+    if (dir->_DIR_fd < 0)
+    {
+        free(dir);
+        dir = NULL;
+    }
+    else
+    {
+        dir->_DIR_avail = 0;
+        dir->_DIR_next  = NULL;
+        pthread_mutex_init( &dir->_DIR_lock, NULL );
+    }
+Exit:
+    return dir;
+}
+
+
+DIR*  fdopendir(int fd)
+{
+    DIR*  dir = malloc(sizeof(DIR));
+
+    if (!dir)
+        return 0;
+
+    dir->_DIR_fd = fd;
+    dir->_DIR_avail = 0;
+    dir->_DIR_next  = NULL;
+    pthread_mutex_init( &dir->_DIR_lock, NULL );
+
+    return dir;
+}
+
+
+static struct dirent*
+_readdir_unlocked(DIR*  dir)
+{
+    struct dirent*  entry;
+
+    if ( !dir->_DIR_avail )
+    {
+        int  rc;
+
+        for (;;) {
+            rc = getdents( dir->_DIR_fd, dir->_DIR_buff, sizeof(dir->_DIR_buff));
+            if (rc >= 0 || errno != EINTR)
+            break;
+        }
+        if (rc <= 0)
+            return NULL;
+
+        dir->_DIR_avail = rc;
+        dir->_DIR_next  = dir->_DIR_buff;
+    }
+
+    entry = dir->_DIR_next;
+
+    /* perform some sanity checks here */
+    if (((long)(void*)entry & 3) != 0)
+        return NULL;
+
+    if ( (unsigned)entry->d_reclen > sizeof(*entry)         ||
+         entry->d_reclen <= offsetof(struct dirent, d_name) )
+        goto Bad;
+
+    if ( (char*)entry + entry->d_reclen > (char*)dir->_DIR_buff + sizeof(dir->_DIR_buff) )
+        goto Bad;
+
+    if ( !memchr( entry->d_name, 0, entry->d_reclen - offsetof(struct dirent, d_name)) )
+        goto Bad; 
+
+    dir->_DIR_next   = (struct dirent*)((char*)entry + entry->d_reclen);
+    dir->_DIR_avail -= entry->d_reclen;
+
+    return entry;
+
+  Bad:
+    errno = EINVAL;
+    return NULL;
+}
+
+
+struct dirent*
+readdir(DIR * dir)
+{
+    struct dirent *entry = NULL;
+
+    pthread_mutex_lock( &dir->_DIR_lock );
+    entry = _readdir_unlocked(dir);
+    pthread_mutex_unlock( &dir->_DIR_lock );
+
+    return entry;
+}
+
+
+int readdir_r(DIR*  dir, struct dirent *entry, struct dirent **result)
+{
+    struct dirent*  ent;
+    int  save_errno = errno;
+    int  retval;
+
+    *result = NULL;
+    errno   = 0;
+
+    pthread_mutex_lock( &dir->_DIR_lock );
+
+    ent    = _readdir_unlocked(dir);
+    retval = errno;
+    if (ent == NULL) {
+        if (!retval) {
+            errno = save_errno;
+        }
+    } else {
+        if (!retval) {
+            errno   = save_errno;
+            *result = entry;
+            memcpy( entry, ent, ent->d_reclen );
+        }
+    }
+
+    pthread_mutex_unlock( &dir->_DIR_lock );
+
+    return retval;
+}
+
+
+
+int closedir(DIR *dir)
+{
+  int rc;
+
+  rc = close(dir->_DIR_fd);
+  dir->_DIR_fd = -1;
+
+  pthread_mutex_destroy( &dir->_DIR_lock );
+
+  free(dir);
+  return rc;
+}
+
+
+void   rewinddir(DIR *dir)
+{
+    pthread_mutex_lock( &dir->_DIR_lock );
+    lseek( dir->_DIR_fd, 0, SEEK_SET );
+    dir->_DIR_avail = 0;
+    pthread_mutex_unlock( &dir->_DIR_lock );
+}
+
+
+int alphasort(const void *a, const void *b)
+{
+        struct dirent **d1, **d2;
+
+        d1 = (struct dirent **) a;
+        d2 = (struct dirent **) b;
+        return strcmp((*d1)->d_name, (*d2)->d_name);
+}
+
+
+int scandir(const char *dir, struct dirent ***namelist,
+            int(*filter)(const struct dirent *),
+            int(*compar)(const struct dirent **, const struct dirent **))
+{
+    DIR *d;
+    int n_elem = 0;
+    struct dirent *this_de, *de;
+    struct dirent **de_list = NULL;
+    int de_list_size = 0;
+
+    d = opendir(dir);
+    if (d == NULL) {
+        return -1;
+    }
+
+    while ((this_de = readdir(d)) != NULL) {
+        if (filter && (*filter)(this_de) == 0) {
+            continue;
+        }
+        if (n_elem == 0) {
+            de_list_size = 4;
+            de_list = (struct dirent **) 
+                    malloc(sizeof(struct dirent *)*de_list_size);
+            if (de_list == NULL) {
+                return -1;
+            }
+        }
+        else if (n_elem == de_list_size) {
+            struct dirent **de_list_new;
+
+            de_list_size += 10;
+            de_list_new = (struct dirent **) 
+                    realloc(de_list, sizeof(struct dirent *)*de_list_size);
+            if (de_list_new == NULL) {
+                free(de_list);
+                return -1;
+            }
+            de_list = de_list_new;
+        }
+        de = (struct dirent *) malloc(sizeof(struct dirent));
+        *de = *this_de;
+        de_list[n_elem++] = de;
+    }
+    closedir(d);
+    if (n_elem && compar) {
+        qsort(de_list, n_elem, sizeof(struct dirent *), 
+              (int (*)(const void *, const void *)) compar);
+    }
+    *namelist = de_list;
+    return n_elem;
+}