[PATCH v2 1/8] tools/rtla: Add common_parse_options()

[Costa Shulyupin <costa.shul@redhat.com>]

Each rtla tool duplicates parsing of many common options. This creates
maintenance overhead and risks inconsistencies when updating these
options.

Add common_parse_options() to centralize parsing of options used across
all tools.

Common options to be migrated in future patches.

Changes since v1:
- restore opterr

Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
---
 tools/tracing/rtla/src/common.c        | 35 ++++++++++++++++++++++++++
 tools/tracing/rtla/src/common.h        |  1 +
 tools/tracing/rtla/src/osnoise_hist.c  |  3 +++
 tools/tracing/rtla/src/osnoise_top.c   |  3 +++
 tools/tracing/rtla/src/timerlat_hist.c |  3 +++
 tools/tracing/rtla/src/timerlat_top.c  |  3 +++
 6 files changed, 48 insertions(+)

diff --git a/tools/tracing/rtla/src/common.c b/tools/tracing/rtla/src/common.c
index b197037fc58b..a78f9883521e 100644
--- a/tools/tracing/rtla/src/common.c
+++ b/tools/tracing/rtla/src/common.c
@@ -5,6 +5,7 @@
 #include <signal.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <getopt.h>
 #include "common.h"
 
 struct trace_instance *trace_inst;
@@ -37,6 +38,40 @@ static void set_signals(struct common_params *params)
 	}
 }
 
+/*
+ * common_parse_options - parse common command line options
+ *
+ * @argc: argument count
+ * @argv: argument vector
+ * @common: common parameters structure
+ *
+ * Parse command line options that are common to all rtla tools.
+ *
+ * Returns: non zero if a common option was parsed, or 0
+ * if the option should be handled by tool-specific parsing.
+ */
+int common_parse_options(int argc, char **argv, struct common_params *common)
+{
+	int saved_state = optind;
+	int c;
+
+	static struct option long_options[] = {
+		{0, 0, 0, 0}
+	};
+
+	opterr = 0;
+	c = getopt_long(argc, argv, "", long_options, NULL);
+	opterr = 1;
+
+	switch (c) {
+	default:
+		optind = saved_state;
+		return 0;
+	}
+
+	return c;
+}
+
 /*
  * common_apply_config - apply common configs to the initialized tool
  */
diff --git a/tools/tracing/rtla/src/common.h b/tools/tracing/rtla/src/common.h
index 9ec2b7632c37..1066d777a823 100644
--- a/tools/tracing/rtla/src/common.h
+++ b/tools/tracing/rtla/src/common.h
@@ -153,6 +153,7 @@ struct osnoise_tool *osnoise_init_tool(char *tool_name);
 struct osnoise_tool *osnoise_init_trace_tool(const char *tracer);
 bool osnoise_trace_is_off(struct osnoise_tool *tool, struct osnoise_tool *record);
 
+int common_parse_options(int argc, char **argv, struct common_params *common);
 int common_apply_config(struct osnoise_tool *tool, struct common_params *params);
 int top_main_loop(struct osnoise_tool *tool);
 int hist_main_loop(struct osnoise_tool *tool);
diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c
index ff8c231e47c4..35f4a068af95 100644
--- a/tools/tracing/rtla/src/osnoise_hist.c
+++ b/tools/tracing/rtla/src/osnoise_hist.c
@@ -518,6 +518,9 @@ static struct common_params
 			{0, 0, 0, 0}
 		};
 
+		if (common_parse_options(argc, argv, &params->common))
+			continue;
+
 		c = getopt_long(argc, argv, "a:c:C::b:d:e:E:DhH:p:P:r:s:S:t::T:01234:5:6:7:",
 				 long_options, NULL);
 
diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
index 04c699bdd736..550731c7addd 100644
--- a/tools/tracing/rtla/src/osnoise_top.c
+++ b/tools/tracing/rtla/src/osnoise_top.c
@@ -370,6 +370,9 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
 			{0, 0, 0, 0}
 		};
 
+		if (common_parse_options(argc, argv, &params->common))
+			continue;
+
 		c = getopt_long(argc, argv, "a:c:C::d:De:hH:p:P:qr:s:S:t::T:0:1:2:3:",
 				 long_options, NULL);
 
diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c
index 1fb471a787b7..ffcfcabb9964 100644
--- a/tools/tracing/rtla/src/timerlat_hist.c
+++ b/tools/tracing/rtla/src/timerlat_hist.c
@@ -834,6 +834,9 @@ static struct common_params
 			{0, 0, 0, 0}
 		};
 
+		if (common_parse_options(argc, argv, &params->common))
+			continue;
+
 		c = getopt_long(argc, argv, "a:c:C::b:d:e:E:DhH:i:knp:P:s:t::T:uU0123456:7:8:9\1\2:\3:",
 				 long_options, NULL);
 
diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c
index 29c2c1f717ed..d18d48671ccd 100644
--- a/tools/tracing/rtla/src/timerlat_top.c
+++ b/tools/tracing/rtla/src/timerlat_top.c
@@ -598,6 +598,9 @@ static struct common_params
 			{0, 0, 0, 0}
 		};
 
+		if (common_parse_options(argc, argv, &params->common))
+			continue;
+
 		c = getopt_long(argc, argv, "a:c:C::d:De:hH:i:knp:P:qs:t::T:uU0:1:2:345:6:7:",
 				 long_options, NULL);
 
-- 
2.52.0