Add headers for the dynamic linker interface.

These are required for libunwind to discover
the exception frame headers.

software/include/dyld/dlfcn.h

@@ -0,0 +1,28 @@
+#ifndef __DLFCN_H
+#define __DLFCN_H
+
+typedef struct
+{
+  const char *dli_fname;        /* File name of defining object.  */
+  void *dli_fbase;              /* Load address of that object.  */
+  const char *dli_sname;        /* Name of nearest symbol.  */
+  void *dli_saddr;              /* Exact value of nearest symbol.  */
+} Dl_info;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern int dl_iterate_phdr (int (*__callback) (struct dl_phdr_info *,
+                                               size_t, void *),
+                            void *__data);
+
+/* Fill in *INFO with the following information about ADDRESS.
+   Returns 0 iff no shared object's segments contain that address.  */
+extern int dladdr (const void *__address, Dl_info *__info);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __DLFCN_H */

software/include/dyld/link.h

@@ -0,0 +1,28 @@
+#ifndef __LIMITS_H
+#define __LIMITS_H
+
+#include <stddef.h>
+#include <elf.h>
+
+#define ElfW(type) Elf32_##type
+
+struct dl_phdr_info {
+  ElfW(Addr) dlpi_addr;
+  const char *dlpi_name;
+  const ElfW(Phdr) *dlpi_phdr;
+  ElfW(Half) dlpi_phnum;
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern int dl_iterate_phdr (int (*__callback) (struct dl_phdr_info *,
+                                               size_t, void *),
+                            void *__data);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LIMITS_H */