// This file is a part of Julia. License is MIT: https://julialang.org/license
// This file defines an RPATH-style relative path loader for all platforms
#include "loader.h"
#ifdef __cplusplus
extern "C" {
#endif
/* Bring in definitions of symbols exported from libjulia. */
#include "jl_exports.h"
/* Bring in helper functions for windows without libgcc. */
#ifdef _OS_WINDOWS_
#include "loader_win_utils.c"
#endif
// Save DEP_LIBS to a variable that is explicitly sized for expansion
static char dep_libs[512] = DEP_LIBS;
JL_DLLEXPORT void jl_loader_print_stderr(const char * msg)
{
fputs(msg, stderr);
}
// I use three arguments a lot.
void jl_loader_print_stderr3(const char * msg1, const char * msg2, const char * msg3)
{
jl_loader_print_stderr(msg1);
jl_loader_print_stderr(msg2);
jl_loader_print_stderr(msg3);
}
/* Wrapper around dlopen(), with extra relative pathing thrown in*/
static void * load_library(const char * rel_path, const char * src_dir) {
void * handle = NULL;
// See if a handle is already open to the basename
const char *basename = rel_path + strlen(rel_path);
while (basename-- > rel_path)
if (*basename == PATHSEPSTRING[0] || *basename == '/')
break;
basename++;
#if defined(_OS_WINDOWS_)
if ((handle = GetModuleHandleW(basename)))
return handle;
#else
if ((handle = dlopen(basename, RTLD_NOLOAD | RTLD_NOW | RTLD_GLOBAL)))
return handle;
#endif
char path[2*PATH_MAX + 1] = {0};
strncat(path, src_dir, sizeof(path) - 1);
strncat(path, PATHSEPSTRING, sizeof(path) - 1);
strncat(path, rel_path, sizeof(path) - 1);
#if defined(_OS_WINDOWS_)
wchar_t wpath[2*PATH_MAX + 1] = {0};
if (!utf8_to_wchar(path, wpath, 2*PATH_MAX)) {
jl_loader_print_stderr3("ERROR: Unable to convert path ", path, " to wide string!\n");
exit(1);
}
handle = (void *)LoadLibraryExW(wpath, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
#else
handle = dlopen(path, RTLD_NOW | RTLD_GLOBAL);
#endif
if (handle == NULL) {
jl_loader_print_stderr3("ERROR: Unable to load dependent library ", path, "\n");
#if defined(_OS_WINDOWS_)
LPWSTR wmsg = TEXT("");
FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS |
FORMAT_MESSAGE_MAX_WIDTH_MASK,
NULL, GetLastError(),
MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US),
(LPWSTR)&wmsg, 0, NULL);
char err[256] = {0};
wchar_to_utf8(wmsg, err, 255);
jl_loader_print_stderr3("Message:", err, "\n");
#else
jl_loader_print_stderr3("Message:", dlerror(), "\n");
#endif
exit(1);
}
return handle;
}
static void * lookup_symbol(const void * lib_handle, const char * symbol_name) {
#ifdef _OS_WINDOWS_
return GetProcAddress((HMODULE) lib_handle, symbol_name);
#else
return dlsym((void *)lib_handle, symbol_name);
#endif
}
// Find the location of libjulia.
char lib_dir[PATH_MAX];
JL_DLLEXPORT const char * jl_get_libdir()
{
// Reuse the path if this is not the first call.
if (lib_dir[0] != 0) {
return lib_dir;
}
#if defined(_OS_WINDOWS_)
// On Windows, we use GetModuleFileNameW
wchar_t libjulia_path[PATH_MAX];
HMODULE libjulia = NULL;
// Get a handle to libjulia.
if (!utf8_to_wchar(LIBJULIA_NAME, libjulia_path, PATH_MAX)) {
jl_loader_print_stderr3("ERROR: Unable to convert path ", LIBJULIA_NAME, " to wide string!\n");
exit(1);
}
libjulia = LoadLibraryW(libjulia_path);
if (libjulia == NULL) {
jl_loader_print_stderr3("ERROR: Unable to load ", LIBJULIA_NAME, "!\n");
exit(1);
}
if (!GetModuleFileNameW(libjulia, libjulia_path, PATH_MAX)) {
jl_loader_print_stderr("ERROR: GetModuleFileName() failed\n");
exit(1);
}
if (!wchar_to_utf8(libjulia_path, lib_dir, PATH_MAX)) {
jl_loader_print_stderr("ERROR: Unable to convert julia path to UTF-8\n");
exit(1);
}
#else
// On all other platforms, use dladdr()
Dl_info info;
if (!dladdr(&jl_get_libdir, &info)) {
jl_loader_print_stderr("ERROR: Unable to dladdr(&jl_get_libdir)!\n");
jl_loader_print_stderr3("Message:", dlerror(), "\n");
exit(1);
}
strcpy(lib_dir, info.dli_fname);
#endif
// Finally, convert to dirname
const char * new_dir = dirname(lib_dir);
if (new_dir != lib_dir) {
// On some platforms, dirname() mutates. On others, it does not.
memcpy(lib_dir, new_dir, strlen(new_dir)+1);
}
return lib_dir;
}
void * libjulia_internal = NULL;
__attribute__((constructor)) void jl_load_libjulia_internal(void) {
// Only initalize this once
if (libjulia_internal != NULL) {
return;
}
// Introspect to find our own path
const char * lib_dir = jl_get_libdir();
// Pre-load libraries that libjulia-internal needs.
int deps_len = strlen(dep_libs);
char * curr_dep = &dep_libs[0];
while (1) {
// try to find next colon character, if we can't, escape out.
char * colon = strchr(curr_dep, ':');
if (colon == NULL)
break;
// Chop the string at the colon, load this library.
*colon = '\0';
load_library(curr_dep, lib_dir);
// Skip ahead to next dependency
curr_dep = colon + 1;
}
// Last dependency is `libjulia-internal`, so load that and we're done with `dep_libs`!
libjulia_internal = load_library(curr_dep, lib_dir);
// Once we have libjulia-internal loaded, re-export its symbols:
for (unsigned int symbol_idx=0; jl_exported_func_names[symbol_idx] != NULL; ++symbol_idx) {
(*jl_exported_func_addrs[symbol_idx]) = lookup_symbol(libjulia_internal, jl_exported_func_names[symbol_idx]);
}
}
// Load libjulia and run the REPL with the given arguments (in UTF-8 format)
JL_DLLEXPORT int jl_load_repl(int argc, char * argv[]) {
// Some compilers/platforms are known to have `__attribute__((constructor))` issues,
// so we have a fallback call of `jl_load_libjulia_internal()` here.
if (libjulia_internal == NULL) {
jl_load_libjulia_internal();
if (libjulia_internal == NULL) {
jl_loader_print_stderr("ERROR: libjulia-internal could not be loaded!\n");
exit(1);
}
}
// Next, if we're on Linux/FreeBSD, set up fast TLS.
#if !defined(_OS_WINDOWS_) && !defined(_OS_DARWIN_)
void (*jl_set_ptls_states_getter)(void *) = lookup_symbol(libjulia_internal, "jl_set_ptls_states_getter");
if (jl_set_ptls_states_getter == NULL) {
jl_loader_print_stderr("ERROR: Cannot find jl_set_ptls_states_getter() function within libjulia-internal!\n");
exit(1);
}
void * (*fptr)(void) = lookup_symbol(RTLD_DEFAULT, "jl_get_ptls_states_static");
if (fptr == NULL) {
jl_loader_print_stderr("ERROR: Cannot find jl_get_ptls_states_static(), must define this symbol within calling executable!\n");
exit(1);
}
jl_set_ptls_states_getter((void *)fptr);
#endif
// Load the repl entrypoint symbol and jump into it!
int (*entrypoint)(int, char **) = (int (*)(int, char **))lookup_symbol(libjulia_internal, "repl_entrypoint");
if (entrypoint == NULL) {
jl_loader_print_stderr("ERROR: Unable to find `repl_entrypoint()` within libjulia-internal!\n");
exit(1);
}
return entrypoint(argc, (char **)argv);
}
#ifdef _OS_WINDOWS_
int __stdcall DllMainCRTStartup(void* instance, unsigned reason, void* reserved) {
// Because we override DllMainCRTStartup, we have to manually call our constructor methods
jl_load_libjulia_internal();
return 1;
}
#endif
#ifdef __cplusplus
} // extern "C"
#endif