From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C92D8C433F5 for ; Fri, 3 Dec 2021 13:34:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352541AbhLCNiE (ORCPT ); Fri, 3 Dec 2021 08:38:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241579AbhLCNh7 (ORCPT ); Fri, 3 Dec 2021 08:37:59 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30151C06173E for ; Fri, 3 Dec 2021 05:34:35 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id d72-20020a1c1d4b000000b00331140f3dc8so2238354wmd.1 for ; Fri, 03 Dec 2021 05:34:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=9Ejg+jt4xVscGt18Qdg892vaZletSiZ1QxqdhJa+MTg=; b=XG6erWuzzmLDqF05yBpPIep4hxAGyWCTv5Aj59kl2HcLdM51f71J+yAQlOm6Lzkgi0 gfmtMlGoRP9xUAi+WS8FzWrJVy6u05EoFB4Iqb1aBCH1CJkq9afEQxfVxDz0ncd4zAVr YxRSvB6HRhK/OBtqW74KHNB3+NOY8qIflKIgkiYp3R3Zs+oVm9u+9MV23SHeMkL+ZcaT xoxeIo6etOlgkOCwBp8wx9ysW60KAnA2C2Z05IPfAAgfNTBruVwxp9SONtohsmjkU4vC HRDXZdNGCAVxo0TF2kXuibI2Dsourx24iQUqbfkZSFrF5RjYWnlH9doKZ+P1CMUTpPZd dLOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=9Ejg+jt4xVscGt18Qdg892vaZletSiZ1QxqdhJa+MTg=; b=sOASOrgbZKx2DzuseKfQBlaP/hyddjhccD1YLhednEqVKnO6kLGSIPQiOZJgXthhyf yijZ44rqbzFCedBZMyA2d/ss+njKoQAn1oGm9IfTKzuCa0Rj+SQL3yHiEfH0jZwNgMNR BtdJOJcQOyO4kvaw36we8eZpA9zz32BRD5P+MPx56XRLKSu4Pm4vrYsETQAZNd+gmdCv QBWn9TOHm30mM0aLDd7LmDO9SnlGKVCpWIgX3MY20ra1Hq9mlOx0LAmDFyS+VEwGg1De 8ZqKVYV7moROUfcqy8YCoeKIaMYtck0Au6fQmR4dAyG0n3WukeoMC1USegy+3TEZk11l B0Lg== X-Gm-Message-State: AOAM531hwmuY/O465raemsMSd040dKpv5QHNNmQDqrcMOKcgtdzje3Wq yk3koNJCCuYqKkmL+MimVJzv9AxAU68= X-Google-Smtp-Source: ABdhPJy845csRs4PwtvB42RhkYEWReiZdRKyyBx1UnX6gUp3Td6siGoxx2ss9eXa6T9NE9V5e+MQSw== X-Received: by 2002:a05:600c:35c8:: with SMTP id r8mr15056268wmq.8.1638538473382; Fri, 03 Dec 2021 05:34:33 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id y142sm2734397wmc.40.2021.12.03.05.34.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Dec 2021 05:34:32 -0800 (PST) Message-Id: <50160d61a41c182d9b8c6c859975f89415de8482.1638538470.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Johannes Schindelin via GitGitGadget" Date: Fri, 03 Dec 2021 13:34:16 +0000 Subject: [PATCH v10 02/15] scalar: create a rudimentary executable Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Derrick Stolee , Eric Sunshine , =?UTF-8?Q?=C3=86var_Arnfj=C3=B6r=C3=B0?= Bjarmason , Elijah Newren , Bagas Sanjaya , Theodore Ts'o , Matt Rogers , Johannes Schindelin , Johannes Schindelin Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Johannes Schindelin The idea of Scalar (https://github.com/microsoft/scalar), and before that, of VFS for Git, has always been to prove that Git _can_ scale, and to upstream whatever strategies have been demonstrated to help. With this patch, we start the journey from that C# project to move what is left to Git's own `contrib/` directory, reimplementing it in pure C, with the intention to facilitate integrating the functionality into core Git all while maintaining backwards-compatibility for existing Scalar users (which will be much easier when both live in the same worktree). It has always been the plan to contribute all of the proven strategies back to core Git. For example, while the virtual filesystem provided by VFS for Git helped the team developing the Windows operating system to move onto Git, while trying to upstream it we realized that it cannot be done: getting the virtual filesystem to work (which we only managed to implement fully on Windows, but not on, say, macOS or Linux), and the required server-side support for the GVFS protocol, made this not quite feasible. The Scalar project learned from that and tackled the problem with different tactics: instead of pretending to Git that the working directory is fully populated, it _specifically_ teaches Git about partial clone (which is based on VFS for Git's cache server), about sparse checkout (which VFS for Git tried to do transparently, in the file system layer), and regularly runs maintenance tasks to keep the repository in a healthy state. With partial clone, sparse checkout and `git maintenance` having been upstreamed, there is little left that `scalar.exe` does which `git.exe` cannot do. One such thing is that `scalar clone ` will automatically set up a partial, sparse clone, and configure known-helpful settings from the start. So let's bring this convenience into Git's tree. The idea here is that you can (optionally) build Scalar via make -C contrib/scalar/ This will build the `scalar` executable and put it into the contrib/scalar/ subdirectory. The slightly awkward addition of the `contrib/scalar/*` bits to the top-level `Makefile` are actually really required: we want to link to `libgit.a`, which means that we will need to use the very same `CFLAGS` and `LDFLAGS` as the rest of Git. An early development version of this patch tried to replicate all the conditional code in `contrib/scalar/Makefile` (e.g. `NO_POLL`) just like `contrib/svn-fe/Makefile` used to do before it was retired. It turned out to be quite the whack-a-mole game: the SHA-1-related flags, the flags enabling/disabling `compat/poll/`, `compat/regex/`, `compat/win32mmap.c` & friends depending on the current platform... To put it mildly: it was a major mess. Instead, this patch makes minimal changes to the top-level `Makefile` so that the bits in `contrib/scalar/` can be compiled and linked, and adds a `contrib/scalar/Makefile` that uses the top-level `Makefile` in a most minimal way to do the actual compiling. Note: With this commit, we only establish the infrastructure, no Scalar functionality is implemented yet; We will do that incrementally over the next few commits. Signed-off-by: Johannes Schindelin --- Makefile | 9 +++++++++ contrib/scalar/.gitignore | 2 ++ contrib/scalar/Makefile | 34 ++++++++++++++++++++++++++++++++++ contrib/scalar/scalar.c | 36 ++++++++++++++++++++++++++++++++++++ 4 files changed, 81 insertions(+) create mode 100644 contrib/scalar/.gitignore create mode 100644 contrib/scalar/Makefile create mode 100644 contrib/scalar/scalar.c diff --git a/Makefile b/Makefile index 12be39ac497..fe898aeea08 100644 --- a/Makefile +++ b/Makefile @@ -2456,6 +2456,11 @@ OBJECTS += $(FUZZ_OBJS) ifndef NO_CURL OBJECTS += http.o http-walker.o remote-curl.o endif + +SCALAR_SOURCES := contrib/scalar/scalar.c +SCALAR_OBJECTS := $(SCALAR_SOURCES:c=o) +OBJECTS += $(SCALAR_OBJECTS) + .PHONY: objects objects: $(OBJECTS) @@ -2589,6 +2594,10 @@ $(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o GIT-LDFLAGS $(GITLIBS $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \ $(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS) +contrib/scalar/scalar$X: $(SCALAR_OBJECTS) GIT-LDFLAGS $(GITLIBS) + $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) \ + $(filter %.o,$^) $(LIBS) + $(LIB_FILE): $(LIB_OBJS) $(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^ diff --git a/contrib/scalar/.gitignore b/contrib/scalar/.gitignore new file mode 100644 index 00000000000..ff3d47e84d0 --- /dev/null +++ b/contrib/scalar/.gitignore @@ -0,0 +1,2 @@ +/*.exe +/scalar diff --git a/contrib/scalar/Makefile b/contrib/scalar/Makefile new file mode 100644 index 00000000000..f6f0036f0fa --- /dev/null +++ b/contrib/scalar/Makefile @@ -0,0 +1,34 @@ +QUIET_SUBDIR0 = +$(MAKE) -C # space to separate -C and subdir +QUIET_SUBDIR1 = + +ifneq ($(findstring s,$(MAKEFLAGS)),s) +ifndef V + QUIET_SUBDIR0 = +@subdir= + QUIET_SUBDIR1 = ;$(NO_SUBDIR) echo ' ' SUBDIR $$subdir; \ + $(MAKE) $(PRINT_DIR) -C $$subdir +else + export V +endif +endif + +all: + +include ../../config.mak.uname +-include ../../config.mak.autogen +-include ../../config.mak + +TARGETS = scalar$(X) scalar.o +GITLIBS = ../../common-main.o ../../libgit.a ../../xdiff/lib.a + +all: scalar$(X) + +$(GITLIBS): + $(QUIET_SUBDIR0)../.. $(QUIET_SUBDIR1) $(subst ../../,,$@) + +$(TARGETS): $(GITLIBS) scalar.c + $(QUIET_SUBDIR0)../.. $(QUIET_SUBDIR1) $(patsubst %,contrib/scalar/%,$@) + +clean: + $(RM) $(TARGETS) + +.PHONY: $(GITLIBS) all clean FORCE diff --git a/contrib/scalar/scalar.c b/contrib/scalar/scalar.c new file mode 100644 index 00000000000..7cff29e0fcd --- /dev/null +++ b/contrib/scalar/scalar.c @@ -0,0 +1,36 @@ +/* + * The Scalar command-line interface. + */ + +#include "cache.h" +#include "gettext.h" +#include "parse-options.h" + +static struct { + const char *name; + int (*fn)(int, const char **); +} builtins[] = { + { NULL, NULL}, +}; + +int cmd_main(int argc, const char **argv) +{ + struct strbuf scalar_usage = STRBUF_INIT; + int i; + + if (argc > 1) { + argv++; + argc--; + + for (i = 0; builtins[i].name; i++) + if (!strcmp(builtins[i].name, argv[0])) + return !!builtins[i].fn(argc, argv); + } + + strbuf_addstr(&scalar_usage, + N_("scalar []\n\nCommands:\n")); + for (i = 0; builtins[i].name; i++) + strbuf_addf(&scalar_usage, "\t%s\n", builtins[i].name); + + usage(scalar_usage.buf); +} -- gitgitgadget