From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtpng1.m.smailru.net (smtpng1.m.smailru.net [94.100.181.251]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dev.tarantool.org (Postfix) with ESMTPS id 987A74765E0 for ; Sat, 26 Dec 2020 17:22:31 +0300 (MSK) Date: Sat, 26 Dec 2020 17:22:25 +0300 From: Igor Munkin Message-ID: <20201226142225.GH5396@tarantool.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Subject: Re: [Tarantool-patches] [PATCH luajit v2 2/7] core: introduce write buffer module List-Id: Tarantool development patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Sergey Kaplun Cc: tarantool-patches@dev.tarantool.org Sergey, Thanks for the patch! LGTM, except the nits below. On 25.12.20, Sergey Kaplun wrote: > This patch introduces the standalone module for writing data to the > file, socket or memory (and so on) via the special buffer. > The module provides the API for buffer initial setup > and its convenient usage. > > Part of tarantool/tarantool#5442 > --- > > Changes in v2: > - Removed custom memcpy. > - lj_wbuf_addn() fills buffer to the end first and then flushes. > - Changed assert in lj_wbuf_flush() to early return. > > src/Makefile | 2 +- > src/Makefile.dep | 23 ++++---- > src/lj_wbuf.c | 141 +++++++++++++++++++++++++++++++++++++++++++++++ > src/lj_wbuf.h | 87 +++++++++++++++++++++++++++++ > src/ljamalg.c | 1 + > 5 files changed, 242 insertions(+), 12 deletions(-) > create mode 100644 src/lj_wbuf.c > create mode 100644 src/lj_wbuf.h > > diff --git a/src/Makefile.dep b/src/Makefile.dep > index 75409bf..59ed450 100644 > --- a/src/Makefile.dep > +++ b/src/Makefile.dep > @@ -211,28 +211,29 @@ lj_vmevent.o: lj_vmevent.c lj_obj.h lua.h luaconf.h lj_def.h lj_arch.h \ > lj_vm.h lj_vmevent.h > lj_vmmath.o: lj_vmmath.c lj_obj.h lua.h luaconf.h lj_def.h lj_arch.h \ > lj_ir.h lj_vm.h > +lj_wbuf.o: lj_wbuf.c lj_wbuf.h lj_def.h lua.h luaconf.h lj_utils.h > ljamalg.o: ljamalg.c lua.h luaconf.h lauxlib.h lj_gc.c lj_obj.h lj_def.h \ > - lj_utils_leb128.c lj_utils.h lib_aux.c lib_base.c lj_libdef.h lib_math.c \ > - lib_string.c lib_table.c lib_io.c lib_os.c lib_package.c lib_debug.c \ > - lib_bit.c lib_jit.c lib_ffi.c lib_misc.c lib_init.c > + lj_utils_leb128.c lib_aux.c lib_base.c lj_libdef.h lib_math.c lib_string.c \ > + lib_table.c lib_io.c lib_os.c lib_package.c lib_debug.c lib_bit.c lib_jit.c \ > + lib_ffi.c lib_misc.c lib_init.c Minor: Why this part is changed? If this is done on purpose, please move this change to the previous patch. Otherwise, looks buggy and I propose to make these changes manually. Feel free to ignore. > luajit.o: luajit.c lua.h luaconf.h lauxlib.h lualib.h luajit.h lj_arch.h > diff --git a/src/lj_wbuf.c b/src/lj_wbuf.c > new file mode 100644 > index 0000000..8f090eb > --- /dev/null > +++ b/src/lj_wbuf.c > @@ -0,0 +1,141 @@ > + /* > + ** Very unlikely: We are told to write a large buffer at once. > + ** Buffer not belong to us so we must to pump data Typo: s/Buffer not belong/Buffer doesn't belong/. > + ** through buffer. Typo: s/through buffer/through the buffer/. > + */ > diff --git a/src/lj_wbuf.h b/src/lj_wbuf.h > new file mode 100644 > index 0000000..58a109e > --- /dev/null > +++ b/src/lj_wbuf.h > @@ -0,0 +1,87 @@ > +typedef size_t (*lj_wbuf_writer)(const void **data, size_t len, void *opt); > + > +/* Write buffer. */ > +struct lj_wbuf { > + /* > + ** Buffer writer which will called at buffer write. Typo: s/will called at buffer write/is called on the buffer flush/. > + ** Should return amount of written bytes on success or zero in case of error. > + ** *data should contain new buffer of size greater or equal to len. If you consider the as a size of the new buffer, then you need to pass its pointer but not its value to the writer. Otherwise this requirement has no sense IMHO. > + ** If *data == NULL stream stops. Minor: It would be nice to describe the contract of this function near its typedef above. > + */ > + lj_wbuf_writer writer; > + /* Context for writer function. */ > + void *ctx; > + /* Buffer size. */ > + size_t size; > + /* Saved errno in case of error. */ > + int saved_errno; There is an empty padding to fit the alignment here. It's better to move this field right prior to the . > + /* Start of buffer. */ > + uint8_t *buf; > + /* Current position in buffer. */ > + uint8_t *pos; > + /* Internal flags. */ > + volatile uint8_t flags; > +}; > + > +/* Init buffer. */ Typo: s/Init buffer/Initialize the buffer/. > +void lj_wbuf_init(struct lj_wbuf *buf, lj_wbuf_writer writer, void *ctx, > + uint8_t *mem, size_t size); > -- > 2.28.0 > -- Best regards, IM