Initial Contribution
diff --git a/libc/unistd/opendir.c b/libc/unistd/opendir.c
new file mode 100644
index 0000000..1b06057
--- /dev/null
+++ b/libc/unistd/opendir.c
@@ -0,0 +1,205 @@
+/*
+ * 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 );
+}
+