From patchwork Tue Jan 28 00:19:02 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josh Steadmon X-Patchwork-Id: 13951950 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E9304567D for ; Tue, 28 Jan 2025 00:19:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738023552; cv=none; b=piYAZoEBqNWxTeuGn70G4LYt6E3CPUmN7aR48rGRbp+//h/RmPSfniUPkr7vUVTp9/sekTT6un1Sda9Xw2GyAqUJOmErSa1iEKQ60SurTUrnbC87DiAgpRPp30NrgYEPp7yaDg6y6H7NW8EhitYkUXQvtoXPxuvmSZI8OkMqliU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738023552; c=relaxed/simple; bh=CcHuSnvH00XLWG0FIpQ+TgQs3ih943r9TX3YnBfIGxA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=dchbIqXswioy9ALdOJ2b8hIZzuAjS7NWDgz/7BYcWL3zP86PPTy0LTYZSYXIhERXa4yX5R0Pvknd21+QhpAJPsCJBDPt8+THVMXjdrTrlpxZ58pb9AjYDD/KRNZgcoipeby2zhUxbwRpp+RVo4TAqyVSI5hfEpmEjhF8ritmfrg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--steadmon.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=H0S41fOo; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--steadmon.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="H0S41fOo" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-216430a88b0so95944635ad.0 for ; Mon, 27 Jan 2025 16:19:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1738023550; x=1738628350; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=O1DZ8akkSqDYmVl2WfQuyLcEPNEXg7FUJybNwNLtAzA=; b=H0S41fOoUpTP2NPBz598+NWpTWHCoHufOHE7UZqXsICUYu0GWK/8WBOXwC/aCzbVsj AhW2nLDGMSmrrZFMflZhy+99SNIQumhPihQVDd7shF8J0x2y/+QsUz+PzKOdJ48aGrkD 5XUcDJWbAO33zjCRexVlhrgpaqFhN2e2owCDRUKHt1ZxIorSXr59UZEMybI5bsvr31bX tBMvkoIFPmTJJ4NIi55ctl05ziWZTRB+B6vaJR2v7mIwZ3+A+HiC+JefTmCOV5HlDtyf Ze4ELnJjnSeUvhgOUMXOAUJ7bCaB1qArxS6TkJjflJffkSAwnJejfRQTfl/thV/j+hPA N1EA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738023550; x=1738628350; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=O1DZ8akkSqDYmVl2WfQuyLcEPNEXg7FUJybNwNLtAzA=; b=pYvfOT6BSToQBgg6l5KlHoiejfsNddUuZc2YAN9ORWILCxgH2HAEkddh8JWRp5UkmC 1cfosEX+NlfQD9dq/AReX8Cd4f3yVTDJ4ee0K6//hu5iYr1O/hMG/oH/zY5BKuRQ4wcW +46ks4csbDNC1HX/O/t411tIb2G2sEOwzoi3HpKXiSEuyohPDFdGxZlw6fYwYxVDbmAb RkG8VhxUGNnbwwoVb57ZJO3gUcPVsrjqZLjSnPGF6KmG2pgkAiXDhe/jbl9MMmS/gdtj LcaL5UVLEpzU2IxNEpD5G3N3tzvGB+MjMKK9ZQehueVC/bpJftrQXKzSFjGQemZ/UqyH 4stQ== X-Gm-Message-State: AOJu0Yxj7M/C3WwIP4oXtZoi0SjvxjNauNeubjnE1PK4sUtqLQkg8KVo ZBE+wbitr+XR8BcO7UkmupX+19iVRRie1BVHyxNGa3oM1wshd0ap18JXAjytuSHAKVSEGmkmPLh uE9QvaeeM8XYRKU5UVuglhB+4XUBC9JprdEkG8+dlrRnTDX5IiadtZoNa/Yk6y47wvfCiu+rXhe AWP0j0ylBOsReYVlA7RnVYe4ITSjxcS2IbFH82BaE= X-Google-Smtp-Source: AGHT+IHqzH8WDwCKh6tgIXhYTvF7e+LgmoftkwMbQr/IvHyvRh/DOBJPFRo3bIGrXGpwF6ha0IQ6Z1akV/38/Q== X-Received: from plblm12.prod.google.com ([2002:a17:903:298c:b0:212:4fad:1dc1]) (user=steadmon job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:40cb:b0:215:a60d:bcc9 with SMTP id d9443c01a7336-21c351bd3bamr641169005ad.2.1738023550018; Mon, 27 Jan 2025 16:19:10 -0800 (PST) Date: Mon, 27 Jan 2025 16:19:02 -0800 In-Reply-To: Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.48.1.262.g85cc9f2d1e-goog Message-ID: Subject: [PATCH v7 1/4] common-main: split init and exit code into new files From: Josh Steadmon To: git@vger.kernel.org Cc: calvinwan@google.com, nasamuffin@google.com, emrass@google.com, gitster@pobox.com, sandals@crustytoothpaste.net, ps@pks.im Currently, object files in libgit.a reference common_exit(), which is contained in common-main.o. However, common-main.o also includes main(), which references cmd_main() in git.o, which in turn depends on all the builtin/*.o objects. We would like to allow external users to link libgit.a without needing to include so many extra objects. Enable this by splitting common_exit() and check_bug_if_BUG() into a new file common-exit.c, and add common-exit.o to LIB_OBJS so that these are included in libgit.a. This split has previously been proposed ([1], [2]) to support fuzz tests and unit tests by avoiding conflicting definitions for main(). However, both of those issues were resolved by other methods of avoiding symbol conflicts. Now we are trying to make libgit.a more self-contained, so hopefully we can revisit this approach. Additionally, move the initialization code out of main() into a new init_git() function in its own file. Include this in libgit.a as well, so that external users can share our setup code without calling our main(). [1] https://lore.kernel.org/git/Yp+wjCPhqieTku3X@google.com/ [2] https://lore.kernel.org/git/20230517-unit-tests-v2-v2-1-21b5b60f4b32@google.com/ Helped-by: Junio C Hamano Signed-off-by: Josh Steadmon --- Makefile | 2 ++ common-exit.c | 26 ++++++++++++++++ common-init.c | 63 ++++++++++++++++++++++++++++++++++++++ common-init.h | 6 ++++ common-main.c | 83 ++------------------------------------------------- meson.build | 2 ++ 6 files changed, 101 insertions(+), 81 deletions(-) create mode 100644 common-exit.c create mode 100644 common-init.c create mode 100644 common-init.h diff --git a/Makefile b/Makefile index 97e8385b66..27e68ac039 100644 --- a/Makefile +++ b/Makefile @@ -981,6 +981,8 @@ LIB_OBJS += combine-diff.o LIB_OBJS += commit-graph.o LIB_OBJS += commit-reach.o LIB_OBJS += commit.o +LIB_OBJS += common-exit.o +LIB_OBJS += common-init.o LIB_OBJS += compat/nonblock.o LIB_OBJS += compat/obstack.o LIB_OBJS += compat/terminal.o diff --git a/common-exit.c b/common-exit.c new file mode 100644 index 0000000000..1aaa538be3 --- /dev/null +++ b/common-exit.c @@ -0,0 +1,26 @@ +#include "git-compat-util.h" +#include "trace2.h" + +static void check_bug_if_BUG(void) +{ + if (!bug_called_must_BUG) + return; + BUG("on exit(): had bug() call(s) in this process without explicit BUG_if_bug()"); +} + +/* We wrap exit() to call common_exit() in git-compat-util.h */ +int common_exit(const char *file, int line, int code) +{ + /* + * For non-POSIX systems: Take the lowest 8 bits of the "code" + * to e.g. turn -1 into 255. On a POSIX system this is + * redundant, see exit(3) and wait(2), but as it doesn't harm + * anything there we don't need to guard this with an "ifdef". + */ + code &= 0xff; + + check_bug_if_BUG(); + trace2_cmd_exit_fl(file, line, code); + + return code; +} diff --git a/common-init.c b/common-init.c new file mode 100644 index 0000000000..5cc73f058c --- /dev/null +++ b/common-init.c @@ -0,0 +1,63 @@ +#define USE_THE_REPOSITORY_VARIABLE + +#include "git-compat-util.h" +#include "common-init.h" +#include "exec-cmd.h" +#include "gettext.h" +#include "attr.h" +#include "repository.h" +#include "setup.h" +#include "strbuf.h" +#include "trace2.h" + +/* + * Many parts of Git have subprograms communicate via pipe, expect the + * upstream of a pipe to die with SIGPIPE when the downstream of a + * pipe does not need to read all that is written. Some third-party + * programs that ignore or block SIGPIPE for their own reason forget + * to restore SIGPIPE handling to the default before spawning Git and + * break this carefully orchestrated machinery. + * + * Restore the way SIGPIPE is handled to default, which is what we + * expect. + */ +static void restore_sigpipe_to_default(void) +{ + sigset_t unblock; + + sigemptyset(&unblock); + sigaddset(&unblock, SIGPIPE); + sigprocmask(SIG_UNBLOCK, &unblock, NULL); + signal(SIGPIPE, SIG_DFL); +} + +void init_git(const char **argv) +{ + struct strbuf tmp = STRBUF_INIT; + + trace2_initialize_clock(); + + /* + * Always open file descriptors 0/1/2 to avoid clobbering files + * in die(). It also avoids messing up when the pipes are dup'ed + * onto stdin/stdout/stderr in the child processes we spawn. + */ + sanitize_stdfds(); + restore_sigpipe_to_default(); + + git_resolve_executable_dir(argv[0]); + + setlocale(LC_CTYPE, ""); + git_setup_gettext(); + + initialize_repository(the_repository); + + attr_start(); + + trace2_initialize(); + trace2_cmd_start(argv); + trace2_collect_process_info(TRACE2_PROCESS_INFO_STARTUP); + + if (!strbuf_getcwd(&tmp)) + tmp_original_cwd = strbuf_detach(&tmp, NULL); +} diff --git a/common-init.h b/common-init.h new file mode 100644 index 0000000000..3e6db20cae --- /dev/null +++ b/common-init.h @@ -0,0 +1,6 @@ +#ifndef COMMON_INIT_H +#define COMMON_INIT_H + +void init_git(const char **argv); + +#endif /* COMMON_INIT_H */ diff --git a/common-main.c b/common-main.c index 8e68ac9e42..6b7ab077b0 100644 --- a/common-main.c +++ b/common-main.c @@ -1,92 +1,13 @@ -#define USE_THE_REPOSITORY_VARIABLE - #include "git-compat-util.h" -#include "exec-cmd.h" -#include "gettext.h" -#include "attr.h" -#include "repository.h" -#include "setup.h" -#include "strbuf.h" -#include "trace2.h" - -/* - * Many parts of Git have subprograms communicate via pipe, expect the - * upstream of a pipe to die with SIGPIPE when the downstream of a - * pipe does not need to read all that is written. Some third-party - * programs that ignore or block SIGPIPE for their own reason forget - * to restore SIGPIPE handling to the default before spawning Git and - * break this carefully orchestrated machinery. - * - * Restore the way SIGPIPE is handled to default, which is what we - * expect. - */ -static void restore_sigpipe_to_default(void) -{ - sigset_t unblock; - - sigemptyset(&unblock); - sigaddset(&unblock, SIGPIPE); - sigprocmask(SIG_UNBLOCK, &unblock, NULL); - signal(SIGPIPE, SIG_DFL); -} +#include "common-init.h" int main(int argc, const char **argv) { int result; - struct strbuf tmp = STRBUF_INIT; - - trace2_initialize_clock(); - - /* - * Always open file descriptors 0/1/2 to avoid clobbering files - * in die(). It also avoids messing up when the pipes are dup'ed - * onto stdin/stdout/stderr in the child processes we spawn. - */ - sanitize_stdfds(); - restore_sigpipe_to_default(); - - git_resolve_executable_dir(argv[0]); - - setlocale(LC_CTYPE, ""); - git_setup_gettext(); - - initialize_repository(the_repository); - - attr_start(); - - trace2_initialize(); - trace2_cmd_start(argv); - trace2_collect_process_info(TRACE2_PROCESS_INFO_STARTUP); - - if (!strbuf_getcwd(&tmp)) - tmp_original_cwd = strbuf_detach(&tmp, NULL); + init_git(argv); result = cmd_main(argc, argv); /* Not exit(3), but a wrapper calling our common_exit() */ exit(result); } - -static void check_bug_if_BUG(void) -{ - if (!bug_called_must_BUG) - return; - BUG("on exit(): had bug() call(s) in this process without explicit BUG_if_bug()"); -} - -/* We wrap exit() to call common_exit() in git-compat-util.h */ -int common_exit(const char *file, int line, int code) -{ - /* - * For non-POSIX systems: Take the lowest 8 bits of the "code" - * to e.g. turn -1 into 255. On a POSIX system this is - * redundant, see exit(3) and wait(2), but as it doesn't harm - * anything there we don't need to guard this with an "ifdef". - */ - code &= 0xff; - - check_bug_if_BUG(); - trace2_cmd_exit_fl(file, line, code); - - return code; -} diff --git a/meson.build b/meson.build index 0064eb64f5..e5ba28b47f 100644 --- a/meson.build +++ b/meson.build @@ -245,6 +245,8 @@ libgit_sources = [ 'commit-graph.c', 'commit-reach.c', 'commit.c', + 'common-exit.c', + 'common-init.c', 'compat/nonblock.c', 'compat/obstack.c', 'compat/terminal.c',