report: support "-o #field_name1,field_name2,..."dev-prajnoha-extended-report-options

The "-o #" replaces the report/compact_output_cols setting
set in lvm.conf in case it's needed for individual report
commands directly on command line:

$ lvs vg
  LV    VG   Attr       LSize Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert LV Tags
  lvol0 vg   -wi-a----- 4.00m

$ lvs vg -o#name,vg_name,pool_lv,origin,data_percent,metadata_percent
  LV    VG   Attr       LSize Move Log Cpy%Sync Convert LV Tags
  lvol0 vg   -wi-a----- 4.00m

2 files changed, 30 insertions, 5 deletions

diff --git a/WHATS_NEW b/WHATS_NEW
index 9bb188375..925ce298b 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.133 - 
 ======================================
+  Recognize "-o #field1,field2,..." to compact reported fields on demand.
   Recognize "-o -field1,field2,..." to remove reported fields on demand.
   Fix lvmcache to move PV from VG to orphans if VG is removed and lvmetad used.
   Fix lvmcache to not cache even invalid info about PV which got removed.
diff --git a/tools/reporter.c b/tools/reporter.c
index f4f9b711c..89024c2fb 100644
--- a/tools/reporter.c
+++ b/tools/reporter.c
@@ -642,17 +642,21 @@ static void _del_option_from_list(struct dm_list *sll, const char *prefix,
 
 static int _get_report_options(struct cmd_context *cmd,
 			       report_type_t report_type,
-			       const char **options)
+			       const char **options,
+			       const char **fields_to_compact)
 {
 	const char *prefix = report_get_field_prefix(report_type);
 	size_t prefix_len = strlen(prefix);
 	struct arg_value_group_list *current_group;
 	struct dm_list *final_opts_list;
+	struct dm_list *final_compact_list = NULL;
 	struct dm_list *opts_list = NULL;
+	int opts_list_destroy = 1;
 	struct dm_str_list *sl;
 	const char *opts;
 	int r = ECMD_PROCESSED;
 
+
 	if (!(final_opts_list = str_to_str_list(NULL, *options, ",", 1))) {
 		r = ECMD_FAILED;
 		goto_out;
@@ -673,6 +677,8 @@ static int _get_report_options(struct cmd_context *cmd,
 			case '+':
 				/* fall through */
 			case '-':
+				/* fall through */
+			case '#':
 				if (!(opts_list = str_to_str_list(NULL, opts + 1, ",", 1))) {
 					r = ECMD_FAILED;
 					goto_out;
@@ -683,8 +689,17 @@ static int _get_report_options(struct cmd_context *cmd,
 					dm_list_iterate_items(sl, opts_list)
 						_del_option_from_list(final_opts_list, prefix,
 								      prefix_len, sl->str);
+				} else if (*opts == '#') {
+					if (!final_compact_list) {
+						final_compact_list = opts_list;
+						opts_list_destroy = 0;
+					} else
+						dm_list_splice(final_compact_list, opts_list);
 				}
-				str_list_destroy(opts_list, 1);
+				if (opts_list_destroy)
+					str_list_destroy(opts_list, 1);
+				else
+					opts_list_destroy = 1;
 				opts_list = NULL;
 				break;
 			default:
@@ -700,9 +715,17 @@ static int _get_report_options(struct cmd_context *cmd,
 		r = ECMD_FAILED;
 		goto out;
 	}
+	if (final_compact_list &&
+	    !(*fields_to_compact = str_list_to_str(cmd->mem, final_compact_list, ","))) {
+		dm_pool_free(cmd->mem, (char *) *options);
+		r = ECMD_FAILED;
+		goto out;
+	}
 out:
 	if (opts_list)
 		str_list_destroy(final_opts_list, 1);
+	if (final_compact_list)
+		str_list_destroy(final_compact_list, 1);
 	if (final_opts_list)
 		str_list_destroy(final_opts_list, 1);
 	return r;
@@ -720,7 +743,7 @@ static int _report(struct cmd_context *cmd, int argc, char **argv,
 	unsigned args_are_pvs;
 	int lv_info_needed, lv_segment_status_needed;
 	int lock_global = 0;
-	const char *fields_to_compact;
+	const char *fields_to_compact = NULL;
 
 	aligned = find_config_tree_bool(cmd, report_aligned_CFG, NULL);
 	buffered = find_config_tree_bool(cmd, report_buffered_CFG, NULL);
@@ -792,7 +815,7 @@ static int _report(struct cmd_context *cmd, int argc, char **argv,
 
 	/* If -o supplied use it, else use default for report_type */
 	if (arg_count(cmd, options_ARG) &&
-	    ((r = _get_report_options(cmd, report_type, &options) != ECMD_PROCESSED)))
+	    ((r = _get_report_options(cmd, report_type, &options, &fields_to_compact) != ECMD_PROCESSED)))
 		return r;
 
 	/* -O overrides default sort settings */
@@ -909,7 +932,8 @@ static int _report(struct cmd_context *cmd, int argc, char **argv,
 	if (find_config_tree_bool(cmd, report_compact_output_CFG, NULL)) {
 		if (!dm_report_compact_fields(report_handle))
 			log_error("Failed to compact report output.");
-	} else if ((fields_to_compact = find_config_tree_str_allow_empty(cmd, report_compact_output_cols_CFG, NULL))) {
+	} else if (fields_to_compact ||
+		   (fields_to_compact = find_config_tree_str_allow_empty(cmd, report_compact_output_cols_CFG, NULL))) {
 		if (!dm_report_compact_given_fields(report_handle, fields_to_compact))
 			log_error("Failed to compact given columns in report output.");
 	}