From patchwork Fri Sep 27 06:10:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 13813867 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C5ECBCEBF76 for ; Fri, 27 Sep 2024 06:14:26 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1su4Ch-0004wP-SA; Fri, 27 Sep 2024 02:11:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1su4CW-0004U6-7w; Fri, 27 Sep 2024 02:11:36 -0400 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1su4CU-0003FU-0M; Fri, 27 Sep 2024 02:11:36 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 4015492D14; Fri, 27 Sep 2024 09:10:51 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id AE919146706; Fri, 27 Sep 2024 09:11:21 +0300 (MSK) Received: (nullmailer pid 573347 invoked by uid 1000); Fri, 27 Sep 2024 06:11:21 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, Michael Tokarev Subject: [PATCH 03/27] qemu-img: global option processing and error printing Date: Fri, 27 Sep 2024 09:10:57 +0300 Message-Id: <20240927061121.573271-4-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20240927061121.573271-1-mjt@tls.msk.ru> References: <20240927061121.573271-1-mjt@tls.msk.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org In order to correctly print executable name in various error messages, pass argv[0] to error_exit() function. This way, error messages will refer to actual executable name, which may be different from 'qemu-img'. For subcommands, pass original command name from the qemu-img argv[0], plus the subcommand name, as its own argv[0] element, so error messages can be more useful. Also don't require at least 3 options on the command line: it makes no sense with options before subcommand. Introduce tryhelp() function which just prints try 'command-name --help' for more info and exits. When tryhelp() is called from within a subcommand handler, the message will look like: try 'command-name subcommand --help' for more info qemu-img uses getopt_long() with ':' as the first char in optstring parameter, which means it doesn't print error messages but return ':' or '?' instead, and qemu-img uses unrecognized_option() or missing_argument() function to print error messages. But it doesn't quite work: $ ./qemu-img -xx qemu-img: unrecognized option './qemu-img' so the aim is to let getopt_long() to print regular error messages instead (removing ':' prefix from optstring) and remove handling of '?' and ':' "options" entirely. With concatenated argv[0] and the subcommand, it all finally does the right thing in all cases. This will be done in subsequent changes command by command, with main() done last. unrecognized_option() and missing_argument() functions prototypes aren't changed by this patch, since they're called from many places and will be removed a few patches later. Only artifical "qemu-img" argv0 is provided in there for now. Signed-off-by: Michael Tokarev Reviewed-by: Kevin Wolf --- qemu-img.c | 80 +++++++++++++++++++++++++++++------------------------- 1 file changed, 43 insertions(+), 37 deletions(-) diff --git a/qemu-img.c b/qemu-img.c index fe22986931..130188e287 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -101,8 +101,15 @@ static void format_print(void *opaque, const char *name) printf(" %s", name); } -static G_NORETURN G_GNUC_PRINTF(1, 2) -void error_exit(const char *fmt, ...) +static G_NORETURN +void tryhelp(const char *argv0) +{ + error_printf("Try '%s --help' for more info\n", argv0); + exit(EXIT_FAILURE); +} + +static G_NORETURN G_GNUC_PRINTF(2, 3) +void error_exit(const char *argv0, const char *fmt, ...) { va_list ap; @@ -110,20 +117,19 @@ void error_exit(const char *fmt, ...) error_vreport(fmt, ap); va_end(ap); - error_printf("Try 'qemu-img --help' for more information\n"); - exit(EXIT_FAILURE); + tryhelp(argv0); } static G_NORETURN void missing_argument(const char *option) { - error_exit("missing argument for option '%s'", option); + error_exit("qemu-img", "missing argument for option '%s'", option); } static G_NORETURN void unrecognized_option(const char *option) { - error_exit("unrecognized option '%s'", option); + error_exit("qemu-img", "unrecognized option '%s'", option); } /* Please keep in synch with docs/tools/qemu-img.rst */ @@ -576,7 +582,7 @@ static int img_create(int argc, char **argv) } if (optind >= argc) { - error_exit("Expecting image file name"); + error_exit(argv[0], "Expecting image file name"); } optind++; @@ -588,7 +594,7 @@ static int img_create(int argc, char **argv) } } if (optind != argc) { - error_exit("Unexpected argument: %s", argv[optind]); + error_exit(argv[0], "Unexpected argument: %s", argv[optind]); } bdrv_img_create(filename, fmt, base_filename, base_fmt, @@ -770,7 +776,7 @@ static int img_check(int argc, char **argv) } else if (!strcmp(optarg, "all")) { fix = BDRV_FIX_LEAKS | BDRV_FIX_ERRORS; } else { - error_exit("Unknown option value for -r " + error_exit(argv[0], "Unknown option value for -r " "(expecting 'leaks' or 'all'): %s", optarg); } break; @@ -795,7 +801,7 @@ static int img_check(int argc, char **argv) } } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } filename = argv[optind++]; @@ -1025,7 +1031,7 @@ static int img_commit(int argc, char **argv) } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } filename = argv[optind++]; @@ -1446,7 +1452,7 @@ static int img_compare(int argc, char **argv) if (optind != argc - 2) { - error_exit("Expecting two image file names"); + error_exit(argv[0], "Expecting two image file names"); } filename1 = argv[optind++]; filename2 = argv[optind++]; @@ -3056,7 +3062,7 @@ static int img_info(int argc, char **argv) } } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } filename = argv[optind++]; @@ -3296,7 +3302,7 @@ static int img_map(int argc, char **argv) } } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } filename = argv[optind]; @@ -3411,7 +3417,7 @@ static int img_snapshot(int argc, char **argv) return 0; case 'l': if (action) { - error_exit("Cannot mix '-l', '-a', '-c', '-d'"); + error_exit(argv[0], "Cannot mix '-l', '-a', '-c', '-d'"); return 0; } action = SNAPSHOT_LIST; @@ -3419,7 +3425,7 @@ static int img_snapshot(int argc, char **argv) break; case 'a': if (action) { - error_exit("Cannot mix '-l', '-a', '-c', '-d'"); + error_exit(argv[0], "Cannot mix '-l', '-a', '-c', '-d'"); return 0; } action = SNAPSHOT_APPLY; @@ -3427,7 +3433,7 @@ static int img_snapshot(int argc, char **argv) break; case 'c': if (action) { - error_exit("Cannot mix '-l', '-a', '-c', '-d'"); + error_exit(argv[0], "Cannot mix '-l', '-a', '-c', '-d'"); return 0; } action = SNAPSHOT_CREATE; @@ -3435,7 +3441,7 @@ static int img_snapshot(int argc, char **argv) break; case 'd': if (action) { - error_exit("Cannot mix '-l', '-a', '-c', '-d'"); + error_exit(argv[0], "Cannot mix '-l', '-a', '-c', '-d'"); return 0; } action = SNAPSHOT_DELETE; @@ -3457,7 +3463,7 @@ static int img_snapshot(int argc, char **argv) } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } filename = argv[optind++]; @@ -3624,10 +3630,11 @@ static int img_rebase(int argc, char **argv) } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } if (!unsafe && !out_baseimg) { - error_exit("Must specify backing file (-b) or use unsafe mode (-u)"); + error_exit(argv[0], + "Must specify backing file (-b) or use unsafe mode (-u)"); } filename = argv[optind++]; @@ -4051,7 +4058,7 @@ static int img_resize(int argc, char **argv) /* Remove size from argv manually so that negative numbers are not treated * as options by getopt. */ if (argc < 3) { - error_exit("Not enough arguments"); + error_exit(argv[0], "Not enough arguments"); return 1; } @@ -4109,7 +4116,7 @@ static int img_resize(int argc, char **argv) } } if (optind != argc - 1) { - error_exit("Expecting image file name and size"); + error_exit(argv[0], "Expecting image file name and size"); } filename = argv[optind++]; @@ -4306,7 +4313,7 @@ static int img_amend(int argc, char **argv) } if (!options) { - error_exit("Must specify options (-o)"); + error_exit(argv[0], "Must specify options (-o)"); } if (quiet) { @@ -4668,7 +4675,7 @@ static int img_bench(int argc, char **argv) } if (optind != argc - 1) { - error_exit("Expecting one image file name"); + error_exit(argv[0], "Expecting one image file name"); } filename = argv[argc - 1]; @@ -5558,9 +5565,6 @@ int main(int argc, char **argv) module_call_init(MODULE_INIT_QOM); bdrv_init(); - if (argc < 2) { - error_exit("Not enough arguments"); - } qemu_add_opts(&qemu_source_opts); qemu_add_opts(&qemu_trace_opts); @@ -5585,15 +5589,11 @@ int main(int argc, char **argv) } } - cmdname = argv[optind]; - - /* reset getopt_long scanning */ - argc -= optind; - if (argc < 1) { - return 0; + if (optind >= argc) { + error_exit(argv[0], "Not enough arguments"); } - argv += optind; - qemu_reset_optind(); + + cmdname = argv[optind]; if (!trace_init_backends()) { exit(1); @@ -5604,10 +5604,16 @@ int main(int argc, char **argv) /* find the command */ for (cmd = img_cmds; cmd->name != NULL; cmd++) { if (!strcmp(cmdname, cmd->name)) { + g_autofree char *argv0 = g_strdup_printf("%s %s", argv[0], cmdname); + /* reset options and getopt processing (incl return order) */ + argv += optind; + argc -= optind; + qemu_reset_optind(); + argv[0] = argv0; return cmd->handler(argc, argv); } } /* not found */ - error_exit("Command not found: %s", cmdname); + error_exit(argv[0], "Command not found: %s", cmdname); }