From 3422e1d6bc3511c5af9cb05ba74ad97dd93ffd7f Mon Sep 17 00:00:00 2001

From: Julien Thierry <jthierry@redhat.com>

Date: Tue, 24 Nov 2020 10:45:24 +0000

Subject: [PATCH] [PATCH 1/2] Add --dry-run option to prevent writing the

 dumpfile

Add a --dry-run option to run all operations without writing the

dump to the output file.

Signed-off-by: Julien Thierry <jthierry@redhat.com>

Signed-off-by: Kazuhito Hagio <k-hagio-ab@nec.com>

---

 makedumpfile.8 |  6 ++++++

 makedumpfile.c | 37 ++++++++++++++++++++++++++++++-------

 makedumpfile.h |  2 ++

 print_info.c   |  3 +++

 4 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/makedumpfile-1.6.8/makedumpfile.8 b/makedumpfile-1.6.8/makedumpfile.8

index b68a7e3..5e902cd 100644

--- a/makedumpfile-1.6.8/makedumpfile.8

+++ b/makedumpfile-1.6.8/makedumpfile.8

@@ -637,6 +637,12 @@ Show the version of makedumpfile.

 Only check whether the command-line parameters are valid or not, and exit.

 Preferable to be given as the first parameter.

+.TP

+\fB\-\-dry-run\fR

+Do not write the output dump file while still performing operations specified

+by other options.

+This option cannot be used with the --dump-dmesg, --reassemble and -g options.

+

 .SH ENVIRONMENT VARIABLES

 .TP 8

diff --git a/makedumpfile-1.6.8/makedumpfile.c b/makedumpfile-1.6.8/makedumpfile.c

index ecd63fa..8c80c49 100644

--- a/makedumpfile-1.6.8/makedumpfile.c

+++ b/makedumpfile-1.6.8/makedumpfile.c

@@ -1372,6 +1372,8 @@ open_dump_file(void)

 	if (info->flag_flatten) {

 		fd = STDOUT_FILENO;

 		info->name_dumpfile = filename_stdout;

+	} else if (info->flag_dry_run) {

+		fd = -1;

 	} else if ((fd = open(info->name_dumpfile, open_flags,

 	    S_IRUSR|S_IWUSR)) < 0) {

 		ERRMSG("Can't open the dump file(%s). %s\n",

@@ -4711,6 +4713,9 @@ write_and_check_space(int fd, void *buf, size_t buf_size, char *file_name)

 {

 	int status, written_size = 0;

+	if (info->flag_dry_run)

+		return TRUE;

+

 	while (written_size < buf_size) {

 		status = write(fd, buf + written_size,

 				   buf_size - written_size);

@@ -4748,13 +4753,12 @@ write_buffer(int fd, off_t offset, void *buf, size_t buf_size, char *file_name)

 		}

 		if (!write_and_check_space(fd, &fdh, sizeof(fdh), file_name))

 			return FALSE;

-	} else {

-		if (lseek(fd, offset, SEEK_SET) == failed) {

-			ERRMSG("Can't seek the dump file(%s). %s\n",

-			    file_name, strerror(errno));

-			return FALSE;

-		}

+	} else if (!info->flag_dry_run &&

+		    lseek(fd, offset, SEEK_SET) == failed) {

+		ERRMSG("Can't seek the dump file(%s). %s\n", file_name, strerror(errno));

+		return FALSE;

 	}

+

 	if (!write_and_check_space(fd, buf, buf_size, file_name))

 		return FALSE;

@@ -9112,7 +9116,7 @@ close_dump_memory(void)

 void

 close_dump_file(void)

 {

-	if (info->flag_flatten)

+	if (info->flag_flatten || info->flag_dry_run)

 		return;

 	if (close(info->fd_dumpfile) < 0)

@@ -10985,6 +10989,11 @@ check_param_for_generating_vmcoreinfo(int argc, char *argv[])

 		return FALSE;

+	if (info->flag_dry_run) {

+		MSG("--dry-run cannot be used with -g.\n");

+		return FALSE;

+	}

+

 	return TRUE;

 }

@@ -11029,6 +11038,11 @@ check_param_for_reassembling_dumpfile(int argc, char *argv[])

 	    || info->flag_exclude_xen_dom || info->flag_split)

 		return FALSE;

+	if (info->flag_dry_run) {

+		MSG("--dry-run cannot be used with --reassemble.\n");

+		return FALSE;

+	}

+

 	if ((info->splitting_info

 	    = malloc(sizeof(struct splitting_info) * info->num_dumpfile))

 	    == NULL) {

@@ -11057,6 +11071,11 @@ check_param_for_creating_dumpfile(int argc, char *argv[])

 	    || (info->flag_read_vmcoreinfo && info->name_xen_syms))

 		return FALSE;

+	if (info->flag_dry_run && info->flag_dmesg) {

+		MSG("--dry-run cannot be used with --dump-dmesg.\n");

+		return FALSE;

+	}

+

 	if (info->flag_flatten && info->flag_split)

 		return FALSE;

@@ -11520,6 +11539,7 @@ static struct option longopts[] = {

 	{"work-dir", required_argument, NULL, OPT_WORKING_DIR},

 	{"num-threads", required_argument, NULL, OPT_NUM_THREADS},

 	{"check-params", no_argument, NULL, OPT_CHECK_PARAMS},

+	{"dry-run", no_argument, NULL, OPT_DRY_RUN},

 	{0, 0, 0, 0}

 };

@@ -11686,6 +11706,9 @@ main(int argc, char *argv[])

 			info->flag_check_params = TRUE;

 			message_level = DEFAULT_MSG_LEVEL;

 			break;

+		case OPT_DRY_RUN:

+			info->flag_dry_run = TRUE;

+			break;

 		case '?':

 			MSG("Commandline parameter is invalid.\n");

 			MSG("Try `makedumpfile --help' for more information.\n");

diff --git a/makedumpfile-1.6.8/makedumpfile.h b/makedumpfile-1.6.8/makedumpfile.h

index 5f50080..4c4222c 100644

--- a/makedumpfile-1.6.8/makedumpfile.h

+++ b/makedumpfile-1.6.8/makedumpfile.h

@@ -1322,6 +1322,7 @@ struct DumpInfo {

 	int		flag_vmemmap;        /* kernel supports vmemmap address space */

 	int		flag_excludevm;      /* -e - excluding unused vmemmap pages */

 	int		flag_use_count;      /* _refcount is named _count in struct page */

+	int		flag_dry_run;        /* do not create a vmcore file */

 	unsigned long	vaddr_for_vtop;      /* virtual address for debugging */

 	long		page_size;           /* size of page */

 	long		page_shift;

@@ -2425,6 +2426,7 @@ struct elf_prstatus {

 #define OPT_NUM_THREADS         OPT_START+16

 #define OPT_PARTIAL_DMESG       OPT_START+17

 #define OPT_CHECK_PARAMS        OPT_START+18

+#define OPT_DRY_RUN             OPT_START+19

 /*

  * Function Prototype.

diff --git a/makedumpfile-1.6.8/print_info.c b/makedumpfile-1.6.8/print_info.c

index e0c38b4..d2b0cb7 100644

--- a/makedumpfile-1.6.8/print_info.c

+++ b/makedumpfile-1.6.8/print_info.c

@@ -308,6 +308,9 @@ print_usage(void)

 	MSG("      the crashkernel range, then calculates the page number of different kind per\n");

 	MSG("      vmcoreinfo. So currently /proc/kcore need be specified explicitly.\n");

 	MSG("\n");

+	MSG("  [--dry-run]:\n");

+	MSG("      This option runs makedumpfile without writting output dump file.\n");

+	MSG("\n");

 	MSG("  [-D]:\n");

 	MSG("      Print debugging message.\n");

 	MSG("\n");

-- 

2.29.2