Btrfs-progs: make pretty_size_snprintf() return len

Sometimes, we need to catch length of snprintf() in pretty_size_snprintf().

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

diff --git a/utils.c b/utils.c
index 2f1d54f..69ae21f 100644 (file)
--- a/utils.c
+++ b/utils.c
@@ -1190,13 +1190,13 @@ out:
 }
 
 static char *size_strs[] = { "", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"};
-void pretty_size_snprintf(u64 size, char *str, size_t str_bytes)
+int pretty_size_snprintf(double size, char *str, size_t str_bytes)
 {
        int num_divs = 0;
        float fraction;
 
        if (str_bytes == 0)
-               return;
+               return 0;
 
        if( size < 1024 ){
                fraction = size;
@@ -1212,11 +1212,12 @@ void pretty_size_snprintf(u64 size, char *str, size_t str_bytes)
 
                if (num_divs >= ARRAY_SIZE(size_strs)) {
                        str[0] = '\0';
-                       return;
+                       return -1;
                }
                fraction = (float)last_size / 1024;
        }
-       snprintf(str, str_bytes, "%.2f%s", fraction, size_strs[num_divs]);
+       return snprintf(str, str_bytes, "%.2f%s", fraction,
+                       size_strs[num_divs]);
 }
 
 /*

diff --git a/utils.h b/utils.h
index a6d3e5e..7a74826 100644 (file)
--- a/utils.h
+++ b/utils.h
@@ -49,11 +49,11 @@ int check_mounted_where(int fd, const char *file, char *where, int size,
 int btrfs_device_already_in_root(struct btrfs_root *root, int fd,
                                 int super_offset);
 
-void pretty_size_snprintf(u64 size, char *str, size_t str_bytes);
+int pretty_size_snprintf(double size, char *str, size_t str_bytes);
 #define pretty_size(size)                                              \
        ({                                                              \
                static __thread char _str[24];                          \
-               pretty_size_snprintf((size), _str, sizeof(_str));       \
+               (void)pretty_size_snprintf((size), _str, sizeof(_str)); \
                _str;                                                   \
        })