libc: add headers and definitions required by libgcc

lib/libc/include/fcntl.h

@@ -1,6 +1,8 @@
 #ifndef FCNTL_H_
 #define FCNTL_H_
 
+#include <sys/types.h>
+
 #define O_RDONLY   0x0000 /* open for reading only */
 #define O_WRONLY   0x0001 /* open for writing only */
 #define O_RDWR     0x0002 /* open for reading and writing */
@@ -50,4 +52,47 @@
 #define AT_SYMLINK_NOFOLLOW_ANY                                                \
 	0x0800 /* Path should not contain any symlinks */
 
+#define S_IRWXU  00700
+#define S_IRUSR  00400
+#define S_IWUSR  00200
+#define S_IXUSR  00100
+#define S_IRWXG  00070
+#define S_IRGRP  00040
+#define S_IWGRP  00020
+#define S_IXGRP  00010
+#define S_IRWXO  00007
+#define S_IROTH  00004
+#define S_IWOTH  00002
+#define S_IXOTH  00001
+#define S_ISUID  0004000
+#define S_ISGID  0002000
+#define S_ISVTX  0001000
+
+#define R_OK     4
+#define W_OK     2
+#define X_OK     1
+#define F_OK     0
+
+#define F_RDLCK  0
+#define F_WRLCK  1
+#define F_SETLKW 7
+
+struct flock {
+	short l_type;
+	short l_whence;
+	off_t l_start;
+	off_t l_len;
+	pid_t l_pid;
+};
+
+struct flock64 {
+	short l_type;
+	short l_whence;
+	off_t l_start;
+	off_t l_len;
+	pid_t l_pid;
+};
+
+extern int fcntl(int fd, int op, ...);
+
 #endif