[PATCH] udev - activate formt length attribute

We carried the the old callout part selector syntax for two releases
now after it was replaced by the new %c{1} syntax. So here we remove
the old syntax and use the code to possibly specify the maximum count
of chars to insert into the string. It will work with all of our format
chars.
I don't know if somebody will use it, but the code is already there :)

's%3s{vendor}' returns "IBM" now, instead of "IBM-ESXS".

Also added is a test for it and a few words in the man page.

1 files changed, 7 insertions, 3 deletions

diff --git a/namedev.c b/namedev.c
index c9232fa2aa..505264554d 100644
--- a/namedev.c
+++ b/namedev.c
@@ -220,7 +220,7 @@ static void apply_format(struct udevice *udev, char *string, size_t maxsize,
 	char *pos2;
 	char *pos3;
 	char *attr;
-	int num;
+	int len;
 	int i;
 	char c;
 	struct sysfs_attribute *tmpattr;
@@ -232,7 +232,7 @@ static void apply_format(struct udevice *udev, char *string, size_t maxsize,
 		if (pos != NULL) {
 			pos[0] = '\0';
 			tail = pos+1;
-			num = get_format_len(&tail);
+			len = get_format_len(&tail);
 			c = tail[0];
 			strfieldcpy(temp, tail+1);
 			tail = temp;
@@ -274,7 +274,7 @@ static void apply_format(struct udevice *udev, char *string, size_t maxsize,
 			if (strlen(udev->program_result) == 0)
 				break;
 			/* get part part of the result string */
-			i = num; /* num syntax is deprecated and will be removed  */
+			i = 0;
 			if (attr != NULL)
 				i = atoi(attr);
 			if (i > 0) {
@@ -317,6 +317,10 @@ static void apply_format(struct udevice *udev, char *string, size_t maxsize,
 			dbg("unknown substitution type '%%%c'", c);
 			break;
 		}
+		/* truncate to specified length */
+		if (len > 0)
+			pos[len] = '\0';
+
 		strnfieldcat(string, tail, maxsize);
 	}
 }