4 files changed, 78 insertions, 2 deletions
diff --git a/lib/find-syms.c b/lib/find-syms.c
index 5e58cb4..78421c5 100644
--- a/lib/find-syms.c
+++ b/lib/find-syms.c
@@ -115,6 +115,7 @@ static void inspect_dyld() {
 }
 
 /* 'dlopen_header' keeps the image alive */
+EXPORT
 struct substitute_image *substitute_open_image(const char *filename) {
 	pthread_once(&dyld_inspect_once, inspect_dyld);
 
@@ -134,17 +135,20 @@ struct substitute_image *substitute_open_image(const char *filename) {
 	return im;
 }
 
+EXPORT
 void substitute_close_image(struct substitute_image *im) {
 	dlclose(im->dlhandle); /* ignore errors */
 	free(im);
 }
 
+EXPORT
 int substitute_find_private_syms(struct substitute_image *im, const char **names,
                          substitute_sym **syms, size_t count) {
 	find_syms_raw(im->image_header, &im->slide, names, syms, count);
 	return SUBSTITUTE_OK;
 }
 
+EXPORT
 void *substitute_sym_to_ptr(struct substitute_image *handle, substitute_sym *sym) {
 	return sym_to_ptr(sym, handle->slide);
 }
diff --git a/lib/substitute-internal.h b/lib/substitute-internal.h
new file mode 100644
index 0000000..cbb7462
--- /dev/null
+++ b/lib/substitute-internal.h
@@ -0,0 +1,10 @@
+#pragma once
+
+#include <stdio.h>
+#define panic(...) do { \
+	fprintf(stderr, __VA_ARGS__); \
+	abort(); \
+	__builtin_unreachable(); \
+} while(0)
+
+#define EXPORT __attribute__ ((visibility("default")))
diff --git a/lib/substitute.h b/lib/substitute.h
index 20dc020..a7fdd31 100644
--- a/lib/substitute.h
+++ b/lib/substitute.h
@@ -8,7 +8,11 @@
 #include <stdlib.h>
 #include <stdint.h>
 
-// TODO add numbers
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* TODO add numbers */
 enum {
     SUBSTITUTE_OK = 0,
 };
@@ -42,7 +46,6 @@ struct substitute_image {
  * @filename the executable/library path (c.f. dyld(3) on Darwin)
  * @return a handle, or NULL if the image wasn't found
  */
-
 struct substitute_image *substitute_open_image(const char *filename);
 
 /* Release a handle opened with substitute_open_image.
@@ -76,3 +79,7 @@ int substitute_find_private_syms(struct substitute_image *handle,
 void *substitute_sym_to_ptr(struct substitute_image *handle, substitute_sym *sym);
 
 #endif /* 1 */
+
+#ifdef __cplusplus
+} /* extern */
+#endif
diff --git a/lib/substrate-compat.c b/lib/substrate-compat.c
new file mode 100644
index 0000000..6bbe316
--- /dev/null
+++ b/lib/substrate-compat.c
@@ -0,0 +1,55 @@
+#include "substitute.h"
+#include "substitute-internal.h"
+#include <syslog.h>
+#include <mach-o/dyld.h>
+
+EXPORT
+void *SubGetImageByName(const char *filename) __asm__("SubGetImageByName");
+void *SubGetImageByName(const char *filename) {
+    return substitute_open_image(filename);
+}
+
+EXPORT
+void *SubFindSymbol(void *image, const char *name) __asm__("SubFindSymbol");
+void *SubFindSymbol(void *image, const char *name) {
+    if (!image) {
+        const char *s = "SubFindSymbol: 'any image' specified, which is incredibly slow - like, 2ms.  I'm going to do it since it seems to be somewhat common, but you should be ashamed of yourself.";
+        syslog(LOG_WARNING, "%s", s);
+        fprintf(stderr, "%s\n", s);
+        /* and it isn't thread safe, but neither is MS */
+        for(uint32_t i = 0; i < _dyld_image_count(); i++) {
+            const char *im_name = _dyld_get_image_name(i);
+            struct substitute_image *im = substitute_open_image(im_name);
+            if (!im) {
+                fprintf(stderr, "(btw, couldn't open %s?)\n", im_name);
+                continue;
+            }
+            void *r = SubFindSymbol(im, name);
+            substitute_close_image(im);
+            if (r)
+                return r;
+        }
+        return NULL;
+    }
+
+    substitute_sym *sym;
+    if (substitute_find_private_syms(image, &name, &sym, 1) || !sym)
+        return NULL;
+    return substitute_sym_to_ptr(image, sym);
+}
+
+/*
+EXPORT
+void SubHookFunction(void *symbol, void *replace, void **result) __asm__("SubHookFunction");
+void SubHookFunction(void *symbol, void *replace, void **result) {
+    // ...
+}
+*/
+
+#ifdef __APPLE__
+/*void SubHookMessageEx(Class _class, SEL sel, IMP imp, IMP *result) __asm__("SubHookMessageEx");
+void SubHookMessageEx(Class _class, SEL sel, IMP imp, IMP *result) {
+
+}*/
+
+#endif