[PATCH 18/20] Btrfs-progs: fix magic return value in cmds-balance.c

[Wang Shilong <wangshilong1991@gmail.com>]

From: Wang Shilong <wangsl.fnst@cn.fujitsu.com>

If there is no balance in progress.resume/pause/cancel will
return 2. For usage or syntal errors will return 1. 0 means
operations return successfully.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
---
 cmds-balance.c | 93 ++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 58 insertions(+), 35 deletions(-)

diff --git a/cmds-balance.c b/cmds-balance.c
index b7382ef..fd68051 100644
--- a/cmds-balance.c
+++ b/cmds-balance.c
@@ -58,7 +58,7 @@ static int parse_one_profile(const char *profile, u64 *flags)
 		*flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE;
 	} else {
 		fprintf(stderr, "Unknown profile '%s'\n", profile);
-		return 1;
+		return -ENOENT;
 	}
 
 	return 0;
@@ -68,12 +68,14 @@ static int parse_profiles(char *profiles, u64 *flags)
 {
 	char *this_char;
 	char *save_ptr = NULL; /* Satisfy static checkers */
+	int ret;
 
 	for (this_char = strtok_r(profiles, "|", &save_ptr);
 	     this_char != NULL;
 	     this_char = strtok_r(NULL, "|", &save_ptr)) {
-		if (parse_one_profile(this_char, flags))
-			return 1;
+		ret = parse_one_profile(this_char, flags);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
@@ -86,7 +88,7 @@ static int parse_u64(const char *str, u64 *result)
 
 	val = strtoull(str, &endptr, 10);
 	if (*endptr)
-		return 1;
+		return -EINVAL;
 
 	*result = val;
 	return 0;
@@ -95,6 +97,7 @@ static int parse_u64(const char *str, u64 *result)
 static int parse_range(const char *range, u64 *start, u64 *end)
 {
 	char *dots;
+	int ret;
 
 	dots = strstr(range, "..");
 	if (dots) {
@@ -107,29 +110,31 @@ static int parse_range(const char *range, u64 *start, u64 *end)
 			*end = (u64)-1;
 			skipped++;
 		} else {
-			if (parse_u64(rest, end))
-				return 1;
+			ret = parse_u64(rest, end);
+			if (ret)
+				return ret;
 		}
 		if (dots == range) {
 			*start = 0;
 			skipped++;
 		} else {
+			ret = parse_u64(rest, end);
 			if (parse_u64(range, start))
-				return 1;
+				return ret;
 		}
 
 		if (*start >= *end) {
 			fprintf(stderr, "Range %llu..%llu doesn't make "
 				"sense\n", (unsigned long long)*start,
 				(unsigned long long)*end);
-			return 1;
+			return -EINVAL;
 		}
 
 		if (skipped <= 1)
 			return 0;
 	}
 
-	return 1;
+	return -EINVAL;
 }
 
 static int parse_filters(char *filters, struct btrfs_balance_args *args)
@@ -137,6 +142,7 @@ static int parse_filters(char *filters, struct btrfs_balance_args *args)
 	char *this_char;
 	char *value;
 	char *save_ptr = NULL; /* Satisfy static checkers */
+	int ret = 0;
 
 	if (!filters)
 		return 0;
@@ -150,70 +156,72 @@ static int parse_filters(char *filters, struct btrfs_balance_args *args)
 			if (!value || !*value) {
 				fprintf(stderr, "the profiles filter requires "
 				       "an argument\n");
-				return 1;
+				return -EINVAL;
 			}
 			if (parse_profiles(value, &args->profiles)) {
 				fprintf(stderr, "Invalid profiles argument\n");
-				return 1;
+				return -EINVAL;
 			}
 			args->flags |= BTRFS_BALANCE_ARGS_PROFILES;
 		} else if (!strcmp(this_char, "usage")) {
 			if (!value || !*value) {
 				fprintf(stderr, "the usage filter requires "
 				       "an argument\n");
-				return 1;
+				return -EINVAL;
 			}
 			if (parse_u64(value, &args->usage) ||
 			    args->usage > 100) {
 				fprintf(stderr, "Invalid usage argument: %s\n",
 				       value);
-				return 1;
+				return -EINVAL;
 			}
 			args->flags |= BTRFS_BALANCE_ARGS_USAGE;
 		} else if (!strcmp(this_char, "devid")) {
 			if (!value || !*value) {
 				fprintf(stderr, "the devid filter requires "
 				       "an argument\n");
-				return 1;
+				return -EINVAL;
 			}
 			if (parse_u64(value, &args->devid) ||
 			    args->devid == 0) {
 				fprintf(stderr, "Invalid devid argument: %s\n",
 				       value);
-				return 1;
+				return -EINVAL;
 			}
 			args->flags |= BTRFS_BALANCE_ARGS_DEVID;
 		} else if (!strcmp(this_char, "drange")) {
 			if (!value || !*value) {
 				fprintf(stderr, "the drange filter requires "
 				       "an argument\n");
-				return 1;
+				return -EINVAL;
 			}
-			if (parse_range(value, &args->pstart, &args->pend)) {
+			ret = parse_range(value, &args->pstart, &args->pend);
+			if (ret) {
 				fprintf(stderr, "Invalid drange argument\n");
-				return 1;
+				return ret;
 			}
 			args->flags |= BTRFS_BALANCE_ARGS_DRANGE;
 		} else if (!strcmp(this_char, "vrange")) {
 			if (!value || !*value) {
 				fprintf(stderr, "the vrange filter requires "
 				       "an argument\n");
-				return 1;
+				return -EINVAL;
 			}
-			if (parse_range(value, &args->vstart, &args->vend)) {
+			ret = parse_range(value, &args->vstart, &args->vend);
+			if (ret) {
 				fprintf(stderr, "Invalid vrange argument\n");
-				return 1;
+				return ret;
 			}
 			args->flags |= BTRFS_BALANCE_ARGS_VRANGE;
 		} else if (!strcmp(this_char, "convert")) {
 			if (!value || !*value) {
 				fprintf(stderr, "the convert option requires "
 				       "an argument\n");
-				return 1;
+				return -EINVAL;
 			}
 			if (parse_one_profile(value, &args->target)) {
 				fprintf(stderr, "Invalid convert argument\n");
-				return 1;
+				return -EINVAL;
 			}
 			args->flags |= BTRFS_BALANCE_ARGS_CONVERT;
 		} else if (!strcmp(this_char, "soft")) {
@@ -221,7 +229,7 @@ static int parse_filters(char *filters, struct btrfs_balance_args *args)
 		} else {
 			fprintf(stderr, "Unrecognized balance option '%s'\n",
 				this_char);
-			return 1;
+			return -EINVAL;
 		}
 	}
 
@@ -297,9 +305,10 @@ static int do_balance(const char *path, struct btrfs_ioctl_balance_args *args,
 	DIR *dirstream = NULL;
 
 	fd = open_file_or_dir(path, &dirstream);
+	e = errno;
 	if (fd < 0) {
 		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
+		return e;
 	}
 
 	ret = ioctl(fd, BTRFS_IOC_BALANCE_V2, args);
@@ -330,7 +339,7 @@ static int do_balance(const char *path, struct btrfs_ioctl_balance_args *args,
 			if (e != EINPROGRESS)
 				fprintf(stderr, "There may be more info in "
 					"syslog - try dmesg | tail\n");
-			ret = 19;
+			ret = 1;
 		}
 	} else {
 		printf("Done, had to relocate %llu out of %llu chunks\n",
@@ -370,6 +379,7 @@ static int cmd_balance_start(int argc, char **argv)
 	int verbose = 0;
 	int nofilters = 1;
 	int i;
+	int ret = 0;
 
 	memset(&args, 0, sizeof(args));
 
@@ -473,7 +483,8 @@ static int cmd_balance_start(int argc, char **argv)
 	if (verbose)
 		dump_ioctl_balance_args(&args);
 
-	return do_balance(argv[optind], &args, nofilters);
+	ret = do_balance(argv[optind], &args, nofilters);
+	return !!ret;
 }
 
 static const char * const cmd_balance_pause_usage[] = {
@@ -498,7 +509,7 @@ static int cmd_balance_pause(int argc, char **argv)
 	fd = open_file_or_dir(path, &dirstream);
 	if (fd < 0) {
 		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
+		return 1;
 	}
 
 	ret = ioctl(fd, BTRFS_IOC_BALANCE_CTL, BTRFS_BALANCE_CTL_PAUSE);
@@ -508,7 +519,10 @@ static int cmd_balance_pause(int argc, char **argv)
 	if (ret < 0) {
 		fprintf(stderr, "ERROR: balance pause on '%s' failed - %s\n",
 			path, (e == ENOTCONN) ? "Not running" : strerror(e));
-		return 19;
+		if (e == ENOTCONN)
+			return 2;
+		else
+			return 1;
 	}
 
 	return 0;
@@ -536,7 +550,7 @@ static int cmd_balance_cancel(int argc, char **argv)
 	fd = open_file_or_dir(path, &dirstream);
 	if (fd < 0) {
 		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
+		return 1;
 	}
 
 	ret = ioctl(fd, BTRFS_IOC_BALANCE_CTL, BTRFS_BALANCE_CTL_CANCEL);
@@ -546,7 +560,10 @@ static int cmd_balance_cancel(int argc, char **argv)
 	if (ret < 0) {
 		fprintf(stderr, "ERROR: balance cancel on '%s' failed - %s\n",
 			path, (e == ENOTCONN) ? "Not in progress" : strerror(e));
-		return 19;
+		if (e == ENOTCONN)
+			return 2;
+		else
+			return 1;
 	}
 
 	return 0;
@@ -575,7 +592,7 @@ static int cmd_balance_resume(int argc, char **argv)
 	fd = open_file_or_dir(path, &dirstream);
 	if (fd < 0) {
 		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
+		return 1;
 	}
 
 	memset(&args, 0, sizeof(args));
@@ -596,12 +613,15 @@ static int cmd_balance_resume(int argc, char **argv)
 				"failed - %s\n", path,
 				(e == ENOTCONN) ? "Not in progress" :
 						  "Already running");
-			return 19;
+			if (e == ENOTCONN)
+				return 2;
+			else
+				return 1;
 		} else {
 			fprintf(stderr,
 "ERROR: error during balancing '%s' - %s\n"
 "There may be more info in syslog - try dmesg | tail\n", path, strerror(e));
-			return 19;
+			return 1;
 		}
 	} else {
 		printf("Done, had to relocate %llu out of %llu chunks\n",
@@ -719,6 +739,8 @@ const struct cmd_group balance_cmd_group = {
 
 int cmd_balance(int argc, char **argv)
 {
+	int ret = 0;
+
 	if (argc == 2) {
 		/* old 'btrfs filesystem balance <path>' syntax */
 		struct btrfs_ioctl_balance_args args;
@@ -726,7 +748,8 @@ int cmd_balance(int argc, char **argv)
 		memset(&args, 0, sizeof(args));
 		args.flags |= BTRFS_BALANCE_TYPE_MASK;
 
-		return do_balance(argv[1], &args, 1);
+		ret = do_balance(argv[1], &args, 1);
+		return !!ret;
 	}
 
 	return handle_command_group(&balance_cmd_group, argc, argv);
-- 
1.7.11.7