[runtime] Work around an ios9 problem where dlopen() cant' find system libraries specified without paths.

5 files changed, 34 insertions, 2 deletions

diff --git a/mono/metadata/loader.c b/mono/metadata/loader.c
index 233efef8aaa..33cd384f434 100644
--- a/mono/metadata/loader.c
+++ b/mono/metadata/loader.c
@@ -1491,7 +1491,7 @@ mono_lookup_pinvoke_call (MonoMethod *method, const char **exc_class, const char
 	/*
 	 * Try loading the module using a variety of names
 	 */
-	for (i = 0; i < 4; ++i) {
+	for (i = 0; i < 5; ++i) {
 		char *base_name = NULL, *dir_name = NULL;
 		gboolean is_absolute = is_absolute_path (new_scope);
 		
@@ -1525,6 +1525,14 @@ mono_lookup_pinvoke_call (MonoMethod *method, const char **exc_class, const char
 				break;
 			}
 			continue;
+		case 3:
+			if (!is_absolute && mono_dl_get_system_dir ()) {
+				dir_name = mono_dl_get_system_dir ();
+				file_name = g_path_get_basename (new_scope);
+				base_name = NULL;
+			} else
+				continue;
+			break;
 		default:
 #ifndef TARGET_WIN32
 			if (!g_ascii_strcasecmp ("user32.dll", new_scope) ||
diff --git a/mono/utils/mono-dl-darwin.c b/mono/utils/mono-dl-darwin.c
index b1cd30f9045..ff7028555c1 100644
--- a/mono/utils/mono-dl-darwin.c
+++ b/mono/utils/mono-dl-darwin.c
@@ -50,4 +50,15 @@ mono_dl_get_executable_path (char *buf, int buflen)
 	return -1;
 }
 
+const char*
+mono_dl_get_system_dir (void)
+{
+#ifdef TARGET_IOS
+	/* IOS9 can't load system libraries using relative paths, i.e. 'libc' doesn't work, but '/usr/lib/libc' does. */
+	return "/usr/lib";
+#else
+	return NULL;
+#endif
+}
+
 #endif
diff --git a/mono/utils/mono-dl-posix.c b/mono/utils/mono-dl-posix.c
index be52a3e6e4c..09eed6222e2 100644
--- a/mono/utils/mono-dl-posix.c
+++ b/mono/utils/mono-dl-posix.c
@@ -47,6 +47,13 @@ mono_dl_get_executable_path (char *buf, int buflen)
 {
 	return readlink ("/proc/self/exe", buf, buflen - 1);
 }
+
+const char*
+mono_dl_get_system_dir (void)
+{
+	return NULL;
+}
+
 #endif
 
 void *
diff --git a/mono/utils/mono-dl-windows.c b/mono/utils/mono-dl-windows.c
index 5dabce44835..19ff818f733 100644
--- a/mono/utils/mono-dl-windows.c
+++ b/mono/utils/mono-dl-windows.c
@@ -159,4 +159,10 @@ mono_dl_get_executable_path (char *buf, int buflen)
 	return -1; //TODO
 }
 
+const char*
+mono_dl_get_system_dir (void)
+{
+	return NULL;
+}
+
 #endif
diff --git a/mono/utils/mono-dl.h b/mono/utils/mono-dl.h
index 4b972ef62f0..c87823208ab 100644
--- a/mono/utils/mono-dl.h
+++ b/mono/utils/mono-dl.h
@@ -34,7 +34,6 @@ char*       mono_dl_build_path (const char *directory, const char *name, void **
 MonoDl*     mono_dl_open_runtime_lib (const char *lib_name, int flags, char **error_msg) MONO_INTERNAL;
 
 
-//Platform API for mono_dl
 const char* mono_dl_get_so_prefix (void) MONO_INTERNAL;
 const char** mono_dl_get_so_suffixes (void) MONO_INTERNAL;
 void* mono_dl_open_file (const char *file, int flags) MONO_INTERNAL;
@@ -43,6 +42,7 @@ void* mono_dl_lookup_symbol (MonoDl *module, const char *name) MONO_INTERNAL;
 int mono_dl_convert_flags (int flags) MONO_INTERNAL;
 char* mono_dl_current_error_string (void) MONO_INTERNAL;
 int mono_dl_get_executable_path (char *buf, int buflen) MONO_INTERNAL;
+const char* mono_dl_get_system_dir (void);
 
 #endif /* __MONO_UTILS_DL_H__ */