#include "gc-core.h"

#include <stdexcept>

#include <glib/gmessages.h>

namespace Inkscape {

namespace GC {

namespace {

void display_warning(char *msg, GC_word arg) {

g_warning(msg, arg);

}

void do_init() {

GC_no_dls = 1;

GC_all_interior_pointers = 1;

GC_finalize_on_demand = 0;

GC_INIT();

GC_set_warn_proc(&display_warning);

}

void *debug_malloc(std::size_t size) {

return GC_debug_malloc(size, GC_EXTRAS);

}

void *debug_malloc_atomic(std::size_t size) {

return GC_debug_malloc_atomic(size, GC_EXTRAS);

}

void *debug_malloc_uncollectable(std::size_t size) {

return GC_debug_malloc_uncollectable(size, GC_EXTRAS);

}

void *debug_malloc_atomic_uncollectable(std::size_t size) {

return GC_debug_malloc_uncollectable(size, GC_EXTRAS);

}

std::ptrdiff_t compute_debug_base_fixup() {

char *base=reinterpret_cast<char *>(GC_debug_malloc(1, GC_EXTRAS));

char *real_base=reinterpret_cast<char *>(GC_base(base));

GC_debug_free(base);

return base - real_base;

}

inline std::ptrdiff_t const &debug_base_fixup() {

static std::ptrdiff_t fixup=compute_debug_base_fixup();

return fixup;

}

void *debug_base(void *ptr) {

char *base=reinterpret_cast<char *>(GC_base(ptr));

return base + debug_base_fixup();

}

int debug_general_register_disappearing_link(void **p_ptr, void *base) {

char *real_base=reinterpret_cast<char *>(base) - debug_base_fixup();

return GC_general_register_disappearing_link(p_ptr, real_base);

}

void dummy_do_init() {}

void *dummy_base(void *) { return NULL; }

void dummy_register_finalizer(void *, CleanupFunc, void *,

CleanupFunc *old_func, void **old_data)

{

if (old_func) {

*old_func = NULL;

}

if (old_data) {

*old_data = NULL;

}

}

int dummy_general_register_disappearing_link(void **, void *) { return false; }

int dummy_unregister_disappearing_link(void **link) { return false; }

std::size_t dummy_get_heap_size() { return 0; }

std::size_t dummy_get_free_bytes() { return 0; }

void dummy_gcollect() {}

void dummy_enable() {}

void dummy_disable() {}

Ops enabled_ops = {

&do_init,

&GC_malloc,

&GC_malloc_atomic,

&GC_malloc_uncollectable,

&GC_malloc_atomic_uncollectable,

&GC_base,

&GC_register_finalizer_ignore_self,

&GC_general_register_disappearing_link,

&GC_unregister_disappearing_link,

&GC_get_heap_size,

&GC_get_free_bytes,

&GC_gcollect,

&GC_enable,

&GC_disable,

&GC_free

};

Ops debug_ops = {

&do_init,

&debug_malloc,

&debug_malloc_atomic,

&debug_malloc_uncollectable,

&debug_malloc_atomic_uncollectable,

&debug_base,

&GC_debug_register_finalizer_ignore_self,

&debug_general_register_disappearing_link,

&GC_unregister_disappearing_link,

&GC_get_heap_size,

&GC_get_free_bytes,

&GC_gcollect,

&GC_enable,

&GC_disable,

&GC_debug_free

};

Ops disabled_ops = {

&dummy_do_init,

&std::malloc,

&std::malloc,

&std::malloc,

&std::malloc,

&dummy_base,

&dummy_register_finalizer,

&dummy_general_register_disappearing_link,

&dummy_unregister_disappearing_link,

&dummy_get_heap_size,

&dummy_get_free_bytes,

&dummy_gcollect,

&dummy_enable,

&dummy_disable,

&std::free

};

class InvalidGCModeError : public std::runtime_error {

public:

InvalidGCModeError(const char *mode)

: runtime_error(std::string("Unknown GC mode \"") + mode + "\"")

{}

};

Ops const &get_ops() throw (InvalidGCModeError) {

char *mode_string=std::getenv("_INKSCAPE_GC");

if (mode_string) {

if (!std::strcmp(mode_string, "enable")) {

return enabled_ops;

} else if (!std::strcmp(mode_string, "debug")) {

return debug_ops;

} else if (!std::strcmp(mode_string, "disable")) {

return disabled_ops;

} else {

throw InvalidGCModeError(mode_string);

}

} else {

return enabled_ops;

}

}

void die_because_not_initialized() {

g_error("Attempt to use GC allocator before call to Inkscape::GC::init()");

}

void *stub_malloc(std::size_t) {

die_because_not_initialized();

return NULL;

}

void *stub_base(void *) {

die_because_not_initialized();

return NULL;

}

void stub_register_finalizer_ignore_self(void *, CleanupFunc, void *,

CleanupFunc *, void **)

{

die_because_not_initialized();

}

int stub_general_register_disappearing_link(void **, void *) {

die_because_not_initialized();

return 0;

}

int stub_unregister_disappearing_link(void **) {

die_because_not_initialized();

return 0;

}

std::size_t stub_get_heap_size() {

die_because_not_initialized();

return 0;

}

std::size_t stub_get_free_bytes() {

die_because_not_initialized();

return 0;

}

void stub_gcollect() {

die_because_not_initialized();

}

void stub_enable() {

die_because_not_initialized();

}

void stub_disable() {

die_because_not_initialized();

}

void stub_free(void *) {

die_because_not_initialized();

}

}

Ops Core::_ops = {

NULL,

&stub_malloc,

&stub_malloc,

&stub_malloc,

&stub_malloc,

&stub_base,

&stub_register_finalizer_ignore_self,

&stub_general_register_disappearing_link,

&stub_unregister_disappearing_link,

&stub_get_heap_size,

&stub_get_free_bytes,

&stub_gcollect,

&stub_enable,

&stub_disable,

&stub_free

};

void Core::init() {

try {

_ops = get_ops();

} catch (InvalidGCModeError &e) {

g_warning("%s; enabling normal collection", e.what());

_ops = enabled_ops;

}

_ops.do_init();

}

}

}