Issue #22222 has been updated by nobu (Nobuyoshi Nakada). `rb_str_new_static` does not `memcpy` (of course you have the responsibility to keep the `String`). ---------------------------------------- Feature #22222: Expose a C API equivalent of `RubyVM::InstructionSequence.load_from_binary` https://bugs.ruby-lang.org/issues/22222#change-118293 * Author: byroot (Jean Boussier) * Status: Open ---------------------------------------- Currently the only API to deserialize instruction sequence is `RubyVM::InstructionSequence.load_from_binary(String)`. It works fine, but isn't ideal for gems like bootsnap, as it needs to allocate a fairly large string and `memcpy` into it. I would like to be able to directly pass a `char *ptr` and `size_t len` pair, so that I can directly pass a internal buffer or even mmapped file. Proposed API: ``` VALUE rb_iseq_load_from_binary(const char *ptr, size_t len) ``` -- https://bugs.ruby-lang.org/

Issue #22222 has been updated by nobu (Nobuyoshi Nakada). The only requirements for `rb_str_new_static` are that the caller is responsible for freeing the allocated memory, and that the memory is not freed while the object is still in existence. You can think of it as requiring the same level of care as when passing a buffer to a system call. The term “static” essentially means that the memory is stable from the perspective of this function. ---------------------------------------- Feature #22222: Expose a C API equivalent of `RubyVM::InstructionSequence.load_from_binary` https://bugs.ruby-lang.org/issues/22222#change-118297 * Author: byroot (Jean Boussier) * Status: Open ---------------------------------------- Currently the only API to deserialize instruction sequence is `RubyVM::InstructionSequence.load_from_binary(String)`. It works fine, but isn't ideal for gems like bootsnap, as it needs to allocate a fairly large string and `memcpy` into it. I would like to be able to directly pass a `char *ptr` and `size_t len` pair, so that I can directly pass a internal buffer or even mmapped file. Proposed API: ``` VALUE rb_iseq_load_from_binary(const char *ptr, size_t len) ``` Pull request: https://github.com/ruby/ruby/pull/18136 -- https://bugs.ruby-lang.org/

Issue #22222 has been updated by Eregon (Benoit Daloze). I guess one concrete issue here with using `rb_str_new_static()` is the mmaped file/stack buffer will be freed soon after the `RubyVM::InstructionSequence.load_from_binary(String)` call, but that String object might live longer, there is no "GC this object now" (AFAIK). And potentially something could get that String via `ObjectSpace.each_object`, and then it'd segfault if the underlying buffer has been freed. ---------------------------------------- Feature #22222: Expose a C API equivalent of `RubyVM::InstructionSequence.load_from_binary` https://bugs.ruby-lang.org/issues/22222#change-118299 * Author: byroot (Jean Boussier) * Status: Open ---------------------------------------- Currently the only API to deserialize instruction sequence is `RubyVM::InstructionSequence.load_from_binary(String)`. It works fine, but isn't ideal for gems like bootsnap, as it needs to allocate a fairly large string and `memcpy` into it. I would like to be able to directly pass a `char *ptr` and `size_t len` pair, so that I can directly pass a internal buffer or even mmapped file. Proposed API: ``` VALUE rb_iseq_load_from_binary(const char *ptr, size_t len) ``` Pull request: https://github.com/ruby/ruby/pull/18136 -- https://bugs.ruby-lang.org/