add option to dlopen with RTLD_GLOBAL (fixes issue #2312)

base/base.jl

@@ -123,7 +123,8 @@ const isimmutable = x->(isa(x,Tuple) || isa(x,Symbol) ||
 dlsym(hnd, s::String) = ccall(:jl_dlsym, Ptr{Void}, (Ptr{Void}, Ptr{Uint8}), hnd, s)
 dlsym(hnd, s::Symbol) = ccall(:jl_dlsym, Ptr{Void}, (Ptr{Void}, Ptr{Uint8}), hnd, s)
 dlsym_e(hnd, s::Union(Symbol,String)) = ccall(:jl_dlsym_e, Ptr{Void}, (Ptr{Void}, Ptr{Uint8}), hnd, s)
-dlopen(s::String) = ccall(:jl_load_dynamic_library, Ptr{Void}, (Ptr{Uint8},), s)
+dlopen(s::String) = ccall(:jl_load_dynamic_library, Ptr{Void}, (Ptr{Uint8},Int32), s, 0)
+dlopen_global(s::String) = ccall(:jl_load_dynamic_library, Ptr{Void}, (Ptr{Uint8},Int32), s, 1)
 dlclose(p::Ptr) = ccall(:uv_dlclose,Void,(Ptr{Void},),p)
 
 cfunction(f::Function, r, a) =

base/exports.jl

@@ -1087,6 +1087,7 @@ export
 # C interface
     c_free,
     dlopen,
+    dlopen_global,
     dlclose,
     dlsym,
     dlsym_e,

doc/stdlib/base.rst

@@ -3007,9 +3007,16 @@ C Interface
 
    Load a shared library, returning an opaque handle.
 
+   There is also a variant :func:`dlopen_global` of this function,
+   which has the same argument and return value but attempts (on Unix)
+   to open the library in a way that makes the library's symbols available
+   to other shared libraries.  (This corresponds to the ``RTLD_GLOBAL`` flag
+   in the POSIX :func:`dlopen` function.)
+
 .. function:: dlsym(handle, sym)
 
-   Look up a symbol from a shared library handle, return callable function pointer on success.
+   Look up a symbol from a shared library handle, return callable
+   function pointer (via :func:`ccall`) on success.
 
 .. function:: dlsym_e(handle, sym)
 

src/ccall.cpp

@@ -70,7 +70,7 @@ static void *add_library_sym(char *name, char *lib)
     else {
         hnd = libMap[lib];
         if (hnd == NULL) {
-            hnd = jl_load_dynamic_library(lib);
+            hnd = jl_load_dynamic_library(lib, 0);
             if (hnd != NULL)
             libMap[lib] = hnd;
             else

src/dlload.c

@@ -34,11 +34,15 @@ extern char *julia_home;
 char *jl_lookup_soname(char *pfx, size_t n);
 #endif
 
-int jl_uv_dlopen(const char* filename, uv_lib_t* lib)
+int jl_uv_dlopen(const char* filename, uv_lib_t* lib, int global)
 {
-#ifdef RTLD_DEEPBIND
+#if defined(RTLD_GLOBAL) && defined(RTLD_LOCAL)
     dlerror(); /* Reset error status. */
-    lib->handle = dlopen(filename, RTLD_LAZY|RTLD_DEEPBIND);
+    lib->handle = dlopen(filename, RTLD_LAZY
+#  ifdef RTLD_DEEPBIND
+                         | RTLD_DEEPBIND
+#  endif
+                         | (global ? RTLD_GLOBAL : RTLD_LOCAL));
     if (lib->handle) {
         lib->errmsg = NULL;
         return 0;
@@ -51,7 +55,10 @@ int jl_uv_dlopen(const char* filename, uv_lib_t* lib)
 #endif
 }
 
-uv_lib_t *jl_load_dynamic_library(char *modname)
+/* load the dynamic library modname.  If global is true, try to
+   load into the global namespace, so that the libraries symbols
+   are available for resolution by subsequent library loads */
+uv_lib_t *jl_load_dynamic_library(char *modname, int global)
 {
     int error;
     char *ext;
@@ -76,7 +83,7 @@ uv_lib_t *jl_load_dynamic_library(char *modname)
 #else
     else if (modname[0] == '/') {
 #endif
-        error = jl_uv_dlopen(modname,handle);
+        error = jl_uv_dlopen(modname,handle,global);
         if (!error) goto done;
     }
 
@@ -86,12 +93,12 @@ uv_lib_t *jl_load_dynamic_library(char *modname)
         handle->handle = NULL;
         /* try loading from standard library path */
         snprintf(path, PATHBUF, "%s%s", modname, ext);
-        error = jl_uv_dlopen(path, handle);
+        error = jl_uv_dlopen(path, handle, global);
         if (!error) goto done;
     }
 #if defined(__linux__)
     char *soname = jl_lookup_soname(modname, strlen(modname));
-    error = (soname==NULL) || jl_uv_dlopen(soname, handle);
+    error = (soname==NULL) || jl_uv_dlopen(soname, handle, global);
     if (!error) goto done;
 #endif
 

src/init.c

@@ -370,7 +370,7 @@ void julia_init(char *imageFile)
 {
     jl_page_size = getPageSize();
     jl_find_stack_bottom();
-    jl_dl_handle = jl_load_dynamic_library(NULL);
+    jl_dl_handle = jl_load_dynamic_library(NULL, 0);
 #ifdef __WIN32__
     uv_dlopen("ntdll.dll",jl_ntdll_handle); //bypass julia's pathchecking for system dlls
     uv_dlopen("Kernel32.dll",jl_kernel32_handle);

src/julia.h

@@ -896,7 +896,7 @@ DLLEXPORT void jl_module_export(jl_module_t *from, jl_sym_t *s);
 void jl_add_standard_imports(jl_module_t *m);
 
 // external libraries
-DLLEXPORT uv_lib_t *jl_load_dynamic_library(char *fname);
+DLLEXPORT uv_lib_t *jl_load_dynamic_library(char *fname, int global);
 DLLEXPORT void *jl_dlsym_e(uv_lib_t *handle, char *symbol);
 DLLEXPORT void *jl_dlsym(uv_lib_t *handle, char *symbol);
 DLLEXPORT uv_lib_t *jl_wrap_raw_dl_handle(void *handle);