[PATCH v2 3/9] part: Give several functions more useful return values

[Sean Anderson]

Several functions in disk/part.c just return -1 on error. This makes them
return different errnos for different failures. This helps callers
differentiate between failures, even if they cannot read stdout.

Signed-off-by: Sean Anderson <sean.anderson at seco.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
---

(no changes since v1)

 disk/part.c | 50 ++++++++++++++++++++++++++++----------------------
 1 file changed, 28 insertions(+), 22 deletions(-)

diff --git a/disk/part.c b/disk/part.c
index b69fd345f3..5e354e256f 100644
--- a/disk/part.c
+++ b/disk/part.c
@@ -354,7 +354,7 @@ int part_get_info(struct blk_desc *dev_desc, int part,
 	}
 #endif /* CONFIG_HAVE_BLOCK_DEVICE */
 
-	return -1;
+	return -ENOENT;
 }
 
 int part_get_info_whole_disk(struct blk_desc *dev_desc,
@@ -416,7 +416,7 @@ int blk_get_device_by_str(const char *ifname, const char *dev_hwpart_str,
 	*dev_desc = get_dev_hwpart(ifname, dev, hwpart);
 	if (!(*dev_desc) || ((*dev_desc)->type == DEV_TYPE_UNKNOWN)) {
 		debug("** Bad device %s %s **\n", ifname, dev_hwpart_str);
-		dev = -ENOENT;
+		dev = -ENODEV;
 		goto cleanup;
 	}
 
@@ -440,7 +440,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 			     struct blk_desc **dev_desc,
 			     struct disk_partition *info, int allow_whole_dev)
 {
-	int ret = -1;
+	int ret;
 	const char *part_str;
 	char *dup_str = NULL;
 	const char *dev_str;
@@ -482,7 +482,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 	if (0 == strcmp(ifname, "ubi")) {
 		if (!ubifs_is_mounted()) {
 			printf("UBIFS not mounted, use ubifsmount to mount volume first!\n");
-			return -1;
+			return -EINVAL;
 		}
 
 		*dev_desc = NULL;
@@ -504,6 +504,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 	/* If still no dev_part_str, it's an error */
 	if (!dev_part_str) {
 		printf("** No device specified **\n");
+		ret = -ENODEV;
 		goto cleanup;
 	}
 
@@ -520,8 +521,10 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 
 	/* Look up the device */
 	dev = blk_get_device_by_str(ifname, dev_str, dev_desc);
-	if (dev < 0)
+	if (dev < 0) {
+		ret = dev;
 		goto cleanup;
+	}
 
 	/* Convert partition ID string to number */
 	if (!part_str || !*part_str) {
@@ -538,6 +541,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 		if (*ep || (part == 0 && !allow_whole_dev)) {
 			printf("** Bad partition specification %s %s **\n",
 			    ifname, dev_part_str);
+			ret = -ENOENT;
 			goto cleanup;
 		}
 	}
@@ -551,6 +555,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 		if (!(*dev_desc)->lba) {
 			printf("** Bad device size - %s %s **\n", ifname,
 			       dev_str);
+			ret = -EINVAL;
 			goto cleanup;
 		}
 
@@ -562,6 +567,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 		if ((part > 0) || (!allow_whole_dev)) {
 			printf("** No partition table - %s %s **\n", ifname,
 			       dev_str);
+			ret = -EPROTONOSUPPORT;
 			goto cleanup;
 		}
 
@@ -630,7 +636,6 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 				*info = tmpinfo;
 		} else {
 			printf("** No valid partitions found **\n");
-			ret = -1;
 			goto cleanup;
 		}
 	}
@@ -638,7 +643,7 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 		printf("** Invalid partition type \"%.32s\""
 			" (expect \"" BOOT_PART_TYPE "\")\n",
 			info->type);
-		ret  = -1;
+		ret  = -EINVAL;
 		goto cleanup;
 	}
 
@@ -674,7 +679,7 @@ int part_get_info_by_name_type(struct blk_desc *dev_desc, const char *name,
 		}
 	}
 
-	return -1;
+	return -ENOENT;
 }
 
 int part_get_info_by_name(struct blk_desc *dev_desc, const char *name,
@@ -704,7 +709,7 @@ static int part_get_info_by_dev_and_name(const char *dev_iface,
 {
 	char *ep;
 	const char *part_str;
-	int dev_num;
+	int dev_num, ret;
 
 	part_str = strchr(dev_part_str, '#');
 	if (!part_str || part_str == dev_part_str)
@@ -720,13 +725,12 @@ static int part_get_info_by_dev_and_name(const char *dev_iface,
 	*dev_desc = blk_get_dev(dev_iface, dev_num);
 	if (!*dev_desc) {
 		printf("Could not find %s %d\n", dev_iface, dev_num);
-		return -EINVAL;
+		return -ENODEV;
 	}
-	if (part_get_info_by_name(*dev_desc, part_str, part_info) < 0) {
+	ret = part_get_info_by_name(*dev_desc, part_str, part_info);
+	if (ret < 0)
 		printf("Could not find \"%s\" partition\n", part_str);
-		return -EINVAL;
-	}
-	return 0;
+	return ret;
 }
 
 int part_get_info_by_dev_and_name_or_num(const char *dev_iface,
@@ -734,21 +738,23 @@ int part_get_info_by_dev_and_name_or_num(const char *dev_iface,
 					 struct blk_desc **dev_desc,
 					 struct disk_partition *part_info)
 {
+	int ret;
+
 	/* Split the part_name if passed as "$dev_num#part_name". */
-	if (!part_get_info_by_dev_and_name(dev_iface, dev_part_str,
-					   dev_desc, part_info))
-		return 0;
+	ret = part_get_info_by_dev_and_name(dev_iface, dev_part_str,
+					    dev_desc, part_info);
+	if (ret >= 0)
+		return ret;
 	/*
 	 * Couldn't lookup by name, try looking up the partition description
 	 * directly.
 	 */
-	if (blk_get_device_part_str(dev_iface, dev_part_str,
-				    dev_desc, part_info, 1) < 0) {
+	ret = blk_get_device_part_str(dev_iface, dev_part_str,
+				      dev_desc, part_info, 1);
+	if (ret < 0)
 		printf("Couldn't find partition %s %s\n",
 		       dev_iface, dev_part_str);
-		return -EINVAL;
-	}
-	return 0;
+	return ret;
 }
 
 void part_set_generic_name(const struct blk_desc *dev_desc,
-- 
2.25.1