add optional RTLD flags argument to dlopen, fixes issue #2312

base/base.jl

@@ -120,10 +120,21 @@ object_id(x::ANY) = ccall(:jl_object_id, Uint, (Any,), x)
 const isimmutable = x->(isa(x,Tuple) || isa(x,Symbol) ||
                         isa(typeof(x),BitsKind))
 
+# constants to match JL_RTLD_* in src/julia.h
+const RTLD_LOCAL     = 0x00000000
+const RTLD_GLOBAL    = 0x00000001
+const RTLD_LAZY      = 0x00000002
+const RTLD_NOW       = 0x00000004
+const RTLD_NODELETE  = 0x00000008
+const RTLD_NOLOAD    = 0x00000010
+const RTLD_DEEPBIND  = 0x00000020
+const RTLD_FIRST     = 0x00000040
+
 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, flags::Integer) = ccall(:jl_load_dynamic_library, Ptr{Void}, (Ptr{Uint8},Uint32), s, flags)
+dlopen(s::String) = dlopen(s, RTLD_LAZY | RTLD_DEEPBIND)
 dlclose(p::Ptr) = ccall(:uv_dlclose,Void,(Ptr{Void},),p)
 
 cfunction(f::Function, r, a) =

base/exports.jl

@@ -150,6 +150,13 @@ export
     NaN,
     NaN32,
     OUTPUT_STREAM,
+    RTLD_LOCAL,
+    RTLD_GLOBAL,
+    RTLD_LAZY,
+    RTLD_NOW,
+    RTLD_NODELETE,
+    RTLD_DEEPBIND,
+    RTLD_FIRST,
     STDERR,
     STDIN,
     STDOUT,

doc/stdlib/base.rst

@@ -3003,10 +3003,22 @@ C Interface
 
    Generate C-callable function pointer from Julia function.
 
-.. function:: dlopen(libfile::String)
+.. function:: dlopen(libfile::String [, flags::Integer])
 
    Load a shared library, returning an opaque handle.
 
+   The optional flags argument is a bitwise-or of zero or more of
+   RTLD_LOCAL, RTLD_GLOBAL, RTLD_LAZY, RTLD_NOW, RTLD_NODELETE,
+   RTLD_NOLOAD, RTLD_DEEPBIND, and RTLD_FIRST.  These are converted to
+   the corresponding flags of the POSIX (and/or GNU libc and/or MacOS)
+   dlopen command, if possible, or are ignored if the specified
+   functionality is not available on the current platform.  The
+   default is RTLD_LAZY|RTLD_DEEPBIND|RTLD_LOCAL.  An important usage
+   of these flags, on POSIX platforms, is to specify
+   RTLD_LAZY|RTLD_DEEPBIND|RTLD_GLOBAL in order for the library's
+   symbols to be available for usage in other shared libraries, in
+   situations where there are dependencies between shared libraries.
+
 .. function:: dlsym(handle, sym)
 
    Look up a symbol from a shared library handle, return callable function pointer on success.

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, JL_RTLD_DEFAULT);
             if (hnd != NULL)
             libMap[lib] = hnd;
             else

src/dlload.c

@@ -34,11 +34,28 @@ 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)
+#define JL_RTLD(flags, FLAG) (flags & JL_RTLD_ ## FLAG ? RTLD_ ## FLAG : 0)
+
+int jl_uv_dlopen(const char* filename, uv_lib_t* lib, unsigned flags)
 {
-#ifdef RTLD_DEEPBIND
+#if defined(RTLD_GLOBAL) && defined(RTLD_LAZY) /* POSIX flags available */
     dlerror(); /* Reset error status. */
-    lib->handle = dlopen(filename, RTLD_LAZY|RTLD_DEEPBIND);
+    lib->handle = dlopen(filename, 
+                         (flags & JL_RTLD_NOW ? RTLD_NOW : RTLD_LAZY)
+                         | JL_RTLD(flags, GLOBAL) | JL_RTLD(flags, LOCAL)
+#ifdef RTLD_NODELETE
+                         | JL_RTLD(flags, NODELETE)
+#endif
+#ifdef RTLD_NOLOAD
+                         | JL_RTLD(flags, NOLOAD)
+#endif
+#ifdef RTLD_DEEPBIND
+                         | JL_RTLD(flags, DEEPBIND)
+#endif
+#ifdef RTLD_FIRST
+                         | JL_RTLD(flags, FIRST)
+#endif
+	 );
     if (lib->handle) {
         lib->errmsg = NULL;
         return 0;
@@ -51,7 +68,7 @@ int jl_uv_dlopen(const char* filename, uv_lib_t* lib)
 #endif
 }
 
-uv_lib_t *jl_load_dynamic_library(char *modname)
+uv_lib_t *jl_load_dynamic_library(char *modname, unsigned flags)
 {
     int error;
     char *ext;
@@ -76,7 +93,7 @@ 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,flags);
         if (!error) goto done;
     }
 
@@ -86,12 +103,12 @@ 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,flags);
         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, flags);
     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, JL_RTLD_DEFAULT);
 #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 +896,16 @@ 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);
+enum JL_RTLD_CONSTANT {
+     JL_RTLD_LOCAL=0U, JL_RTLD_GLOBAL=1U, /* LOCAL=0 since it is the default */
+     JL_RTLD_LAZY=2U, JL_RTLD_NOW=4U,
+     /* Linux/glibc and MacOS X: */
+     JL_RTLD_NODELETE=8U, JL_RTLD_NOLOAD=16U, 
+     /* Linux/glibc: */ JL_RTLD_DEEPBIND=32U,
+     /* MacOS X 10.5+: */ JL_RTLD_FIRST=64U
+};
+#define JL_RTLD_DEFAULT (JL_RTLD_LAZY | JL_RTLD_DEEPBIND)
+DLLEXPORT uv_lib_t *jl_load_dynamic_library(char *fname, unsigned flags);
 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);