From 989152e113bfcb4fbfbad6f3aed6f43be4455919 Mon Sep 17 00:00:00 2001
From: Kazuhito Hagio <k-hagio-ab@nec.com>
Date: Tue, 25 Feb 2020 16:04:55 -0500
Subject: [PATCH] Introduce --check-params option

Currently it's difficult to check whether a makedumpfile command-line
is valid or not without an actual panic.  This is inefficient and if
a wrong configuration is not tested, you will miss the vmcore when an
actual panic occurs.

In order for kdump facilities like kexec-tools to be able to check
the specified command-line parameters in advance, introduce the
--check-params option that only checks them and exits immediately.

Signed-off-by: Kazuhito Hagio <k-hagio-ab@nec.com>
---
 makedumpfile.8 |  5 ++++
 makedumpfile.c | 75 ++++++++++++++++++++++++++++++++++++++------------
 print_info.c   |  4 +++
 4 files changed, 69 insertions(+), 17 deletions(-)

diff --git a/makedumpfile-1.6.7/makedumpfile.8 b/makedumpfile-1.6.7/makedumpfile.8
index bf156a8..c5d4806 100644
--- a/makedumpfile-1.6.7/makedumpfile.8
+++ b/makedumpfile-1.6.7/makedumpfile.8
@@ -632,6 +632,11 @@ Show help message and LZO/snappy support status (enabled/disabled).
 \fB\-v\fR
 Show the version of makedumpfile.
 
+.TP
+\fB\-\-check-params\fR
+Only check whether the command-line parameters are valid or not, and exit.
+Preferable to be given as the first parameter.
+
 .SH ENVIRONMENT VARIABLES
 
 .TP 8
diff --git a/makedumpfile-1.6.7/makedumpfile.c b/makedumpfile-1.6.7/makedumpfile.c
index 607e07f..f5860a1 100644
--- a/makedumpfile-1.6.7/makedumpfile.c
+++ b/makedumpfile-1.6.7/makedumpfile.c
@@ -10978,12 +10978,6 @@ check_param_for_creating_dumpfile(int argc, char *argv[])
 	if (info->flag_generate_vmcoreinfo || info->flag_rearrange)
 		return FALSE;
 
-	if ((message_level < MIN_MSG_LEVEL)
-	    || (MAX_MSG_LEVEL < message_level)) {
-		message_level = DEFAULT_MSG_LEVEL;
-		MSG("Message_level is invalid.\n");
-		return FALSE;
-	}
 	if ((info->flag_compress && info->flag_elf_dumpfile)
 	    || (info->flag_read_vmcoreinfo && info->name_vmlinux)
 	    || (info->flag_read_vmcoreinfo && info->name_xen_syms))
@@ -11013,6 +11007,11 @@ check_param_for_creating_dumpfile(int argc, char *argv[])
 	if (info->flag_partial_dmesg && !info->flag_dmesg)
 		return FALSE;
 
+	if (info->flag_excludevm && !info->working_dir) {
+		MSG("-%c requires --work-dir\n", OPT_EXCLUDE_UNUSED_VM);
+		return FALSE;
+	}
+
 	if ((argc == optind + 2) && !info->flag_flatten
 				 && !info->flag_split
 				 && !info->flag_sadump_diskset) {
@@ -11408,6 +11407,23 @@ int show_mem_usage(void)
 	return TRUE;
 }
 
+static int set_message_level(char *str_ml)
+{
+	int ml;
+
+	ml = atoi(str_ml);
+	if ((ml < MIN_MSG_LEVEL) || (MAX_MSG_LEVEL < ml)) {
+		message_level = DEFAULT_MSG_LEVEL;
+		MSG("Message_level(%d) is invalid.\n", ml);
+		return FALSE;
+	}
+
+	if (info->flag_check_params)
+		return TRUE;
+
+	message_level = ml;
+	return TRUE;
+}
 
 static struct option longopts[] = {
 	{"split", no_argument, NULL, OPT_SPLIT},
@@ -11429,6 +11445,7 @@ static struct option longopts[] = {
 	{"splitblock-size", required_argument, NULL, OPT_SPLITBLOCK_SIZE},
 	{"work-dir", required_argument, NULL, OPT_WORKING_DIR},
 	{"num-threads", required_argument, NULL, OPT_NUM_THREADS},
+	{"check-params", no_argument, NULL, OPT_CHECK_PARAMS},
 	{0, 0, 0, 0}
 };
 
@@ -11527,7 +11544,8 @@ main(int argc, char *argv[])
 			info->flag_compress = DUMP_DH_COMPRESSED_LZO;
 			break;
 		case OPT_MESSAGE_LEVEL:
-			message_level = atoi(optarg);
+			if (!set_message_level(optarg))
+				goto out;
 			break;
 		case OPT_DUMP_DMESG:
 			info->flag_dmesg = 1;
@@ -11590,6 +11608,10 @@ main(int argc, char *argv[])
 		case OPT_NUM_THREADS:
 			info->num_threads = MAX(atoi(optarg), 0);
 			break;
+		case OPT_CHECK_PARAMS:
+			info->flag_check_params = TRUE;
+			message_level = DEFAULT_MSG_LEVEL;
+			break;
 		case '?':
 			MSG("Commandline parameter is invalid.\n");
 			MSG("Try `makedumpfile --help' for more information.\n");
@@ -11599,11 +11621,9 @@ main(int argc, char *argv[])
 	if (flag_debug)
 		message_level |= ML_PRINT_DEBUG_MSG;
 
-	if (info->flag_excludevm && !info->working_dir) {
-		ERRMSG("Error: -%c requires --work-dir\n", OPT_EXCLUDE_UNUSED_VM);
-		ERRMSG("Try `makedumpfile --help' for more information\n");
-		return COMPLETED;
-	}
+	if (info->flag_check_params)
+		/* suppress debugging messages */
+		message_level = DEFAULT_MSG_LEVEL;
 
 	if (info->flag_show_usage) {
 		print_usage();
@@ -11634,6 +11654,9 @@ main(int argc, char *argv[])
 			MSG("Try `makedumpfile --help' for more information.\n");
 			goto out;
 		}
+		if (info->flag_check_params)
+			goto check_ok;
+
 		if (!open_files_for_generating_vmcoreinfo())
 			goto out;
 
@@ -11657,6 +11680,9 @@ main(int argc, char *argv[])
 			MSG("Try `makedumpfile --help' for more information.\n");
 			goto out;
 		}
+		if (info->flag_check_params)
+			goto check_ok;
+
 		if (!check_dump_file(info->name_dumpfile))
 			goto out;
 
@@ -11677,6 +11703,9 @@ main(int argc, char *argv[])
 			MSG("Try `makedumpfile --help' for more information.\n");
 			goto out;
 		}
+		if (info->flag_check_params)
+			goto check_ok;
+
 		if (!check_dump_file(info->name_dumpfile))
 			goto out;
 
@@ -11690,6 +11719,9 @@ main(int argc, char *argv[])
 			MSG("Try `makedumpfile --help' for more information.\n");
 			goto out;
 		}
+		if (info->flag_check_params)
+			goto check_ok;
+
 		if (!check_dump_file(info->name_dumpfile))
 			goto out;
 		if (!dump_dmesg())
@@ -11703,6 +11735,9 @@ main(int argc, char *argv[])
 			MSG("Try `makedumpfile --help' for more information.\n");
 			goto out;
 		}
+		if (info->flag_check_params)
+			goto check_ok;
+
 		if (!populate_kernel_version())
 			goto out;
 
@@ -11721,6 +11756,9 @@ main(int argc, char *argv[])
 			MSG("Try `makedumpfile --help' for more information.\n");
 			goto out;
 		}
+		if (info->flag_check_params)
+			goto check_ok;
+
 		if (info->flag_split) {
 			for (i = 0; i < info->num_dumpfile; i++) {
 				SPLITTING_FD_BITMAP(i) = -1;
@@ -11748,13 +11786,16 @@ main(int argc, char *argv[])
 			MSG("The dumpfile is saved to %s.\n", info->name_dumpfile);
 		}
 	}
+check_ok:
 	retcd = COMPLETED;
 out:
-	MSG("\n");
-	if (retcd != COMPLETED)
-		MSG("makedumpfile Failed.\n");
-	else if (!info->flag_mem_usage)
-		MSG("makedumpfile Completed.\n");
+	if (!info->flag_check_params) {
+		MSG("\n");
+		if (retcd != COMPLETED)
+			MSG("makedumpfile Failed.\n");
+		else if (!info->flag_mem_usage)
+			MSG("makedumpfile Completed.\n");
+	}
 
 	free_for_parallel();
 
diff --git a/makedumpfile-1.6.7/makedumpfile.h b/makedumpfile-1.6.7/makedumpfile.h
index 7217407..03fb4ce 100644
--- a/makedumpfile-1.6.7/makedumpfile.h
+++ b/makedumpfile-1.6.7/makedumpfile.h
@@ -1303,6 +1303,7 @@ struct DumpInfo {
 	int		flag_read_vmcoreinfo;    /* flag of reading vmcoreinfo file */
 	int		flag_show_usage;     /* flag of showing usage */
 	int		flag_show_version;   /* flag of showing version */
+	int		flag_check_params;   /* only check parameters */
 	int		flag_flatten;        /* flag of outputting flattened
 						format to a standard out */
 	int		flag_rearrange;      /* flag of creating dumpfile from
@@ -2364,6 +2365,7 @@ struct elf_prstatus {
 #define OPT_WORKING_DIR         OPT_START+15
 #define OPT_NUM_THREADS         OPT_START+16
 #define OPT_PARTIAL_DMESG       OPT_START+17
+#define OPT_CHECK_PARAMS        OPT_START+18
 
 /*
  * Function Prototype.
diff --git a/makedumpfile-1.6.7/print_info.c b/makedumpfile-1.6.7/print_info.c
index 0be12ea..e0c38b4 100644
--- a/makedumpfile-1.6.7/print_info.c
+++ b/makedumpfile-1.6.7/print_info.c
@@ -321,6 +321,10 @@ print_usage(void)
 	MSG("  [-v]:\n");
 	MSG("      Show the version of makedumpfile.\n");
 	MSG("\n");
+	MSG("  [--check-params]:\n");
+	MSG("      Only check whether the command-line parameters are valid or not, and exit.\n");
+	MSG("      Preferable to be given as the first parameter.\n");
+	MSG("\n");
 	MSG("  VMLINUX:\n");
 	MSG("      This is a pathname to the first kernel's vmlinux.\n");
 	MSG("      This file must have the debug information of the first kernel to analyze\n");
-- 
2.24.1