From: kay.sievers@vrfy.org <kay.sievers@vrfy.org>
Date: Tue, 18 Nov 2003 08:59:27 +0000 (-0800)
Subject: [PATCH] implement printf-like placeholder support for NAME
X-Git-Tag: 006~26
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=98b88dbf704a1376ee4c79051086089adde5d626

[PATCH] implement printf-like placeholder support for NAME

> Problem is, if you use the LABEL rule to match a device, like a SCSI
> vendor, then all of the partitions, as well as the main block device,
> will end up with the same name.  That's why I added the "add the number"
> hack to the LABEL rule.
>
> So yes, your patch is correct in that we shouldn't always be adding the
> number to any match for LABEL (like for char devices), but if we do
> that, then we break partitions.  Your '%' patch fixes this, but I'd just
> like to extend it a bit.  Let me see what I can come up with...

Oh, I see. Do you mean something like this:

LABEL, BUS="usb", model="Creative Labs WebCam 3", NAME="webcam%n-%M:%m-test"

results in: "webcam0-81:0-test"

Nov 15 16:51:53 pim udev[16193]: get_class_dev: looking at /sys/class/video4linux/video0
Nov 15 16:51:53 pim udev[16193]: get_class_dev: class_dev->name = video0
Nov 15 16:51:53 pim udev[16193]: get_major_minor: dev = 81:0
Nov 15 16:51:53 pim udev[16193]: get_major_minor: found major = 81, minor = 0
Nov 15 16:51:53 pim udev[16193]: udev_add_device: name = webcam0-81:0-test
Nov 15 16:51:53 pim udev[16193]: create_node: mknod(/udev/webcam0-81:0-test, 020666, 81, 0)



  implement printf-like placeholder support for NAME
  %n-kernel number, %M-major number, %m-minor number
---

diff --git a/namedev.c b/namedev.c
index d76d03b49..f6be43ef5 100644
--- a/namedev.c
+++ b/namedev.c
@@ -817,6 +817,37 @@ static int get_attr(struct sysfs_class_device *class_dev, struct udevice *udev)
 	strcpy(udev->name, class_dev->name);
 
 done:
+	/* substitute placeholder in NAME  */
+	while (1) {
+		pos = strchr(udev->name, '%');
+		if (pos) {
+			strcpy(name, pos+2);
+			*pos = 0x00;
+			switch (pos[1]) {
+			case 'n':
+				dig = class_dev->name + strlen(class_dev->name);
+				while (isdigit(*(dig-1)))
+					dig--;
+				strcat(udev->name, dig);
+				dbg_parse("kernel number appended: %s", dig);
+				break;
+			case 'm':
+				sprintf(pos, "%u", udev->minor);
+				dbg_parse("minor number appended: %u", udev->minor);
+				break;
+			case 'M':
+				sprintf(pos, "%u", udev->major);
+				dbg_parse("major number appended: %u", udev->major);
+				break;
+			default:
+				dbg_parse("unknown substitution type: %%%c", pos[1]);
+				break;
+			}
+			strcat(udev->name, name);
+		} else
+			break;
+	}
+
 	/* mode was never set above */
 	if (!udev->mode) {
 		udev->mode = get_default_mode(class_dev);