[libgpiod PATCH 2/7] tools: Add line name to offset lookup helper

[Joel Stanley]

line_names_to_offsets to be used by tools that support --by-name.

Signed-off-by: Joel Stanley <joel at jms.id.au>
---
 tools/tools-common.c | 22 ++++++++++++++++++++++
 tools/tools-common.h |  2 ++
 2 files changed, 24 insertions(+)

diff --git a/tools/tools-common.c b/tools/tools-common.c
index c83e68a2c1e4..958933ed6d51 100644
--- a/tools/tools-common.c
+++ b/tools/tools-common.c
@@ -204,3 +204,25 @@ struct gpiod_chip *chip_by_line_name(const char *name)
 	return NULL;
 }
 
+int line_names_to_offsets(struct gpiod_chip *chip, char **lines,
+			  unsigned int *offsets, int num_lines)
+{
+	int i;
+
+	for (i = 0; i < num_lines; i++) {
+		const char *line_name = lines[i];
+		int offset;
+
+		offset = gpiod_chip_find_line(chip, line_name);
+
+		if (offset < 0) {
+			die("chip '%s' does not contain line '%s'",
+					gpiod_chip_get_name(chip),
+					line_name);
+		}
+
+		offsets[i] = offset;
+	}
+
+	return 0;
+}
diff --git a/tools/tools-common.h b/tools/tools-common.h
index 5ed37dc05885..7affea436a60 100644
--- a/tools/tools-common.h
+++ b/tools/tools-common.h
@@ -32,5 +32,7 @@ int chip_dir_filter(const struct dirent *entry);
 struct gpiod_chip *chip_open_by_name(const char *name);
 struct gpiod_chip *chip_open_lookup(const char *device);
 struct gpiod_chip *chip_by_line_name(const char *name);
+int line_names_to_offsets(struct gpiod_chip *chip, char **lines,
+			  unsigned int *offsets, int num_lines);
 
 #endif /* __GPIOD_TOOLS_COMMON_H__ */
-- 
2.34.1