From be323732d0ee3af8f75f9286ab6f630b4ee0c1cf Mon Sep 17 00:00:00 2001
From: Laurent Vivier <Laurent@lvivier.info>
Date: Thu, 1 Jun 2006 22:17:33 +0000
Subject: [PATCH] change API of get_dev and get_rdev: return driver major
 number instead of device pathname

---
 libemile/emile_scsi_create_container.c |  4 +--
 libemile/emile_scsi_get_dev.c          | 41 ++++++++++++++++++++------
 libemile/emile_scsi_get_rdev.c         | 10 ++-----
 3 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/libemile/emile_scsi_create_container.c b/libemile/emile_scsi_create_container.c
index ec42310..aa65b73 100644
--- a/libemile/emile_scsi_create_container.c
+++ b/libemile/emile_scsi_create_container.c
@@ -49,14 +49,14 @@ static int get_device_info(int fd, short *id, unsigned long *first_block,
 	unsigned char channel;
 	unsigned char pun;
 	unsigned char lun;
-	char *driver;
+	int driver;
 	int disk;
 	int partition;
 
 	ret = emile_scsi_get_dev(fd, &driver, &disk, &partition);
 	if (ret == -1)
 		return -1;
-	sprintf(dev_name, "%s%c%d", driver, disk + 'a', partition);
+	emile_get_dev_name(dev_name, driver, disk, partition);
 
 	fd = open(dev_name, O_RDONLY);
 	if (fd == -1) {
diff --git a/libemile/emile_scsi_get_dev.c b/libemile/emile_scsi_get_dev.c
index a836a6e..d6e7e22 100644
--- a/libemile/emile_scsi_get_dev.c
+++ b/libemile/emile_scsi_get_dev.c
@@ -12,14 +12,34 @@ static __attribute__((used)) char* rcsid = "$CVSHeader$";
 
 #include "libemile.h"
 
-/* SCSI disks */
+int emile_get_dev_name(char *buffer, int driver, int disk, int partition)
+{
+	switch(driver)
+	{
+		case MAJOR_HD:
+			if (partition == 0)
+				sprintf(buffer, "/dev/hd%c", 'a' + disk);
+			else
+				sprintf(buffer, "/dev/hd%c%d", 'a' + disk, 
+						partition);
+			break;
+		case MAJOR_LOOP:
+			sprintf(buffer, "/dev/loop%d", disk);
+			break;
+		case MAJOR_SD:
+			if (partition == 0)
+				sprintf(buffer, "/dev/sd%c", 'a' + disk);
+			else
+				sprintf(buffer, "/dev/sd%c%d", 'a' + disk, 
+						partition);
+			break;
+		default:
+			return -1;
+	}
+	return 0;
+}
 
-#define MAJOR_HD	3
-#define MAJOR_SD	8
-static char *scsi_base = "/dev/sd";
-static char *ata_base = "/dev/hd";
-
-int emile_scsi_get_dev(int fd, char** driver, int *disk, int *partition)
+int emile_scsi_get_dev(int fd, int* driver, int *disk, int *partition)
 {
 	struct stat st;
 	int ret;
@@ -36,15 +56,18 @@ int emile_scsi_get_dev(int fd, char** driver, int *disk, int *partition)
 	major = (dev >> 8) & 0x0F;	/* major number = driver id */
 	minor = dev & 0xFF;		/* minor number = disk id */
 
+	*driver = major;
 	switch(major)
 	{
 	case MAJOR_SD:	/* SCSI disks */
-		*driver = scsi_base;
 		*disk = minor >> 4;
 		*partition = minor & 0x0F;
 		break;
+	case MAJOR_LOOP: /* loop device */
+		*disk = minor & 0xFF;
+		*partition = 0;
+		break;
 	case MAJOR_HD:	/* ATA disks */
-		*driver = ata_base;
 		*disk = minor >> 6;
 		*partition = minor & 0x3F;
 		break;
diff --git a/libemile/emile_scsi_get_rdev.c b/libemile/emile_scsi_get_rdev.c
index 11e4f3b..f024c28 100644
--- a/libemile/emile_scsi_get_rdev.c
+++ b/libemile/emile_scsi_get_rdev.c
@@ -8,12 +8,7 @@ static __attribute__((used)) char* rcsid = "$CVSHeader$";
 #include "partition.h"
 #include "libemile.h"
 
-#define MAJOR_HD	3
-#define MAJOR_SD	8
-static char *scsi_base = "/dev/sd";
-static char *ide_base = "/dev/hd";
-
-int emile_scsi_get_rdev(char* dev_name, char** driver, int *disk, int *partition)
+int emile_scsi_get_rdev(char* dev_name, int* driver, int *disk, int *partition)
 {
 	int ret;
 	struct stat st;
@@ -28,15 +23,14 @@ int emile_scsi_get_rdev(char* dev_name, char** driver, int *disk, int *partition
 		return -1;
 
 	major = (st.st_rdev >> 8) & 0x0F;
+	*driver = major;
 	switch(major)
 	{
 	case MAJOR_SD:
-		*driver = scsi_base;
 		*disk = (st.st_rdev & 0xFF) >> 4;
 		*partition = st.st_rdev &  0x0F;
 		break;
 	case MAJOR_HD:
-		*driver = ide_base;
 		*disk = (st.st_rdev & 0xFF) >> 6;
 		*partition = st.st_rdev &  0x3F;
 		break;