[PATCH 0/2] Support for small units in display

[PATCH 0/2] Support for small units in display

[Pierre Carrier]

Allow better inspection of sizes using an environment variable.

Not pretty, but convenient to determine the exact size of a filesystem,
eg when resizing an underlying partition or LUN.

Pierre Carrier (2):
  utils.c: fix sizes in B & malloc in pretty_sizes
  utils.c: offer to limit divisions in pretty_sizes

 utils.c | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

-- 
1.7.11.1

[PATCH 1/2] utils.c: fix sizes in B & malloc in pretty_sizes

[Pierre Carrier]

Before, sizes below 1KB where displayed in KB,
but without a unit.

Signed-off-by: Pierre Carrier <pierre@spotify.com>

diff --git a/utils.c b/utils.c
index aade9e2..dde0513 100644
--- a/utils.c
+++ b/utils.c
@@ -1108,13 +1108,20 @@ char *pretty_sizes(u64 size)
 		size /= 1024;
 		num_divs++;
 	}
-	if (num_divs == 0)
+	if (num_divs == 0) {
 		num_divs = 1;
+		fraction = (float)fract_size;
+	} else
+		fraction = (float)fract_size / 1024;
+
 	if (num_divs > ARRAY_SIZE(size_strs))
 		return NULL;
 
-	fraction = (float)fract_size / 1024;
+
 	pretty = malloc(pretty_len);
+	if (!pretty)
+		return NULL;
+
 	snprintf(pretty, pretty_len, "%.2f%s", fraction, size_strs[num_divs-1]);
 	return pretty;
 }
-- 
1.7.11.1

[PATCH 2/2] utils.c: offer to limit divisions in pretty_sizes

[Pierre Carrier]

Dirty hack to allow inspection of sizes in lower units.

Useful to know the minimum size a partition shoud be resized to
after a 'btrfs filesystem resize'.

Label: 'home'  uuid: 10453c4c-1c5b-4df5-b4a5-43a7f377430a
        Total devices 1 FS bytes used 42.80GB
        devid    1 size 62.16GB used 62.16GB path /dev/sda5

Label: 'home'  uuid: 10453c4c-1c5b-4df5-b4a5-43a7f377430a
        Total devices 1 FS bytes used 44884524.00KB
        devid    1 size 65182236.00KB used 65182208.00KB path /dev/sda5

Signed-off-by: Pierre Carrier <pierre@spotify.com>

diff --git a/utils.c b/utils.c
index dde0513..e660799 100644
--- a/utils.c
+++ b/utils.c
@@ -1096,13 +1096,18 @@ static char *size_strs[] = { "", "KB", "MB", "GB", "TB",
 char *pretty_sizes(u64 size)
 {
 	int num_divs = 0;
+	int max_divs = INT_MAX;
         int pretty_len = 16;
 	u64 last_size = size;
 	u64 fract_size = size;
 	float fraction;
 	char *pretty;
+	char *max_divs_s;
 
-	while(size > 0) {
+	if (max_divs_s = getenv("MAX_DIVS"))
+		max_divs = atoi(max_divs_s);
+
+	while(size > 0 && num_divs < max_divs) {
 		fract_size = last_size;
 		last_size = size;
 		size /= 1024;
-- 
1.7.11.1

[PATCH 0/2] Support for small units in display

[Pierre Carrier]

I didn't test the initial patches enough.
A second round is coming.

This time it works fine:
devid    1 size 66746609664.00 used 66746580992.00 path /dev/sda5
devid    1 size 65182236.00KB used 65182208.00KB path /dev/sda5
devid    1 size 63654.53MB used 63654.50MB path /dev/sda5
devid    1 size 62.16GB used 62.16GB path /dev/sda5
devid    1 size 62.16GB used 62.16GB path /dev/sda5


Pierre Carrier (2):
  utils.c: fix sizes in B & malloc in pretty_sizes
  utils.c: offer to limit divisions in pretty_sizes

 utils.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

-- 
1.7.11.1

[PATCH 1/2] utils.c: fix sizes in B & malloc in pretty_sizes

[Pierre Carrier]

Before, sizes below 1KB are still displayed in KB,
but without a unit.

Signed-off-by: Pierre Carrier <pierre@spotify.com>

diff --git a/utils.c b/utils.c
index aade9e2..937e763 100644
--- a/utils.c
+++ b/utils.c
@@ -1108,13 +1108,20 @@ char *pretty_sizes(u64 size)
 		size /= 1024;
 		num_divs++;
 	}
-	if (num_divs == 0)
+	if (num_divs <= 1) {
 		num_divs = 1;
+		fraction = (float)fract_size;
+	} else
+		fraction = (float)fract_size / 1024;
+
 	if (num_divs > ARRAY_SIZE(size_strs))
 		return NULL;
 
-	fraction = (float)fract_size / 1024;
+
 	pretty = malloc(pretty_len);
+	if (!pretty)
+		return NULL;
+
 	snprintf(pretty, pretty_len, "%.2f%s", fraction, size_strs[num_divs-1]);
 	return pretty;
 }
-- 
1.7.11.1

[PATCH 2/2] utils.c: offer to limit divisions in pretty_sizes

[Pierre Carrier]

Dirty hack to allow inspection of sizes in lower units.

Useful to know the minimum size a partition shoud be resized to
after a 'btrfs filesystem resize'.

Label: 'home'  uuid: 10453c4c-1c5b-4df5-b4a5-43a7f377430a
        Total devices 1 FS bytes used 42.80GB
        devid    1 size 62.16GB used 62.16GB path /dev/sda5

Label: 'home'  uuid: 10453c4c-1c5b-4df5-b4a5-43a7f377430a
        Total devices 1 FS bytes used 44884524.00KB
        devid    1 size 65182236.00KB used 65182208.00KB path /dev/sda5

Signed-off-by: Pierre Carrier <pierre@spotify.com>

diff --git a/utils.c b/utils.c
index 937e763..3f0b7e7 100644
--- a/utils.c
+++ b/utils.c
@@ -1096,13 +1096,18 @@ static char *size_strs[] = { "", "KB", "MB", "GB", "TB",
 char *pretty_sizes(u64 size)
 {
 	int num_divs = 0;
+	int max_divs = INT_MAX;
         int pretty_len = 16;
 	u64 last_size = size;
 	u64 fract_size = size;
 	float fraction;
 	char *pretty;
+	char *max_divs_s;
 
-	while(size > 0) {
+	if (max_divs_s = getenv("MAX_DIVS"))
+		max_divs = atoi(max_divs_s);
+
+	while(size > 0 && num_divs <= max_divs) {
 		fract_size = last_size;
 		last_size = size;
 		size /= 1024;
@@ -1117,7 +1122,6 @@ char *pretty_sizes(u64 size)
 	if (num_divs > ARRAY_SIZE(size_strs))
 		return NULL;
 
-
 	pretty = malloc(pretty_len);
 	if (!pretty)
 		return NULL;
-- 
1.7.11.1

Re: [PATCH 0/2] Support for small units in display

[David Sterba]

On Mon, Jul 09, 2012 at 05:27:41PM +0000, Pierre Carrier wrote:
> I didn't test the initial patches enough.
> A second round is coming.

Please indicate the updated version by eg. adding a v2 to the subject of
the cover letter and describe the changes, makes it more clear to
maintainers/reviewers what to look at, thanks.


david

Re: [PATCH 1/2] utils.c: fix sizes in B & malloc in pretty_sizes

[David Sterba]

On Mon, Jul 09, 2012 at 05:29:34PM +0000, Pierre Carrier wrote:
> Before, sizes below 1KB are still displayed in KB,
> but without a unit.

Does it matter when the only size below 1KB one can get is 0 ? Though
for sake of consistency the B unit could be there in that case as well.

Re: [PATCH 2/2] utils.c: offer to limit divisions in pretty_sizes

[David Sterba]

On Mon, Jul 09, 2012 at 05:30:21PM +0000, Pierre Carrier wrote:
> Dirty hack to allow inspection of sizes in lower units.

A commandline option would suit better IMHO. If this is a one-shot task
to find the sizes expressed with a different multiplier, then I don't
understhand the env variable approach. If it's meant to express all
size-related numbers with a given multiplier, than it could make sense,
but it has to be well documented and possibly a better variable name
picked.

Hugo referenced one of his patches,
http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg06518.html
that adds -h or -H (1024-based and SI-based), but that does not fix the
problem that you want to se a specific size. So, I'm suggesting a
generic option

--units=PFX

where PFX can be arbitrary from KB, KiB and the rest of the list. Plus a
way to include the human-readable forms, both 1024- and SI-based.


david