It's safe to use sprintf() for simple cases in device_attr_show
type of functions. Add support for sprintf() in patch mode to
the device_attr_show.cocci script to print numbers and pointers.
Signed-off-by: Denis Efremov <[email protected]>
---
Interesting enough that with this patch coccinelle starts to skip
patch generation in some cases. For example, it skips patch for
drivers/base/core.c This is an unexpected result for me.
scripts/coccinelle/api/device_attr_show.cocci | 30 +++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/scripts/coccinelle/api/device_attr_show.cocci b/scripts/coccinelle/api/device_attr_show.cocci
index d8ec4bb8ac41..1248b8c76cfe 100644
--- a/scripts/coccinelle/api/device_attr_show.cocci
+++ b/scripts/coccinelle/api/device_attr_show.cocci
@@ -30,15 +30,45 @@ ssize_t show(struct device *dev, struct device_attribute *attr, char *buf)
@rp depends on patch@
identifier show, dev, attr, buf;
+constant str;
@@
ssize_t show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
+(
+ return
+- snprintf
++ sprintf
+ (buf,
+- \(PAGE_SIZE\|PAGE_SIZE - 1\),
+ str);
+|
+ return
+- snprintf
++ sprintf
+ (buf,
+- \(PAGE_SIZE\|PAGE_SIZE - 1\),
+ \("%i"\|"%i\n"\|"%li"\|"%li\n"\|"%lli"\|"%lli\n"\|
+ "%d"\|"%d\n"\|"%ld"\|"%ld\n"\|"%lld"\|"%lld\n"\|
+ "%u"\|"%u\n"\|"%lu"\|"%lu\n"\|"%llu"\|"%llu\n"\|
+ "%x"\|"%x\n"\|"%lx"\|"%lx\n"\|"%llx"\|"%llx\n"\|
+ "%X"\|"%X\n"\|"%lX"\|"%lX\n"\|"%llX"\|"%llX\n"\|
+ "0x%x"\|"0x%x\n"\|"0x%lx"\|"0x%lx\n"\|"0x%llx"\|"0x%llx\n"\|
+ "0x%X"\|"0x%X\n"\|"0x%lX"\|"0x%lX\n"\|"0x%llX"\|"0x%llX\n"\|
+ "%02x\n"\|"%03x\n"\|"%04x\n"\|"%08x\n"\|
+ "%02X\n"\|"%03X\n"\|"%04X\n"\|"%08X\n"\|
+ "0x%02x\n"\|"0x%03x\n"\|"0x%04x\n"\|"0x%08x\n"\|
+ "0x%02X\n"\|"0x%03X\n"\|"0x%04X\n"\|"0x%08X\n"\|
+ "%zd"\|"%zd\n"\|"%zu"\|"%zu\n"\|"%zx"\|"%zx\n"\|
+ "%c"\|"%c\n"\|"%p"\|"%p\n"\|"%pU\n"\|"%pUl\n"\|"%hu\n"\),
+ ...);
+|
return
- snprintf
+ scnprintf
(...);
+)
...>
}
--
2.26.2
Hi,
Markus, I think that CCing new people and spam them with mails they
are obviously not interested in doesn't bring an additional value to
the discussion. linux-kernel and cocci mailing lists are enough
in my opinion. This also will allow us to keep "threaded" mail
order.
On 8/14/20 11:30 AM, Markus Elfring wrote:
>> Interesting enough that with this patch coccinelle starts to skip
>> patch generation in some cases. For example, it skips patch for
>> drivers/base/core.c This is an unexpected result for me.
>
> Would you like to point questionable differences for such patch hunks out?
Without this patch the script generates:
$ spatch -D patch --no-includes --include-headers --cocci-file scripts/coccinelle/api/device_attr_show.cocci drivers/base/core.c
--- drivers/base/core.c
+++ /tmp/cocci-output-63510-2f17ff-core.c
@@ -1713,7 +1713,7 @@ ssize_t device_show_ulong(struct device
char *buf)
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
+ return scnprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_ulong);
@@ -1743,7 +1743,7 @@ ssize_t device_show_int(struct device *d
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
+ return scnprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_int);
@@ -1764,7 +1764,7 @@ ssize_t device_show_bool(struct device *
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
+ return scnprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_bool);
With this patch it generates nothing. I would expect spatch to generate
a different patch with sprintf instead of scnprintf, because I think
... is enough to match "*(int *)(ea->var)". Even if it can't match sprintf
pattern it should fallback to scnprintf pattern.
> You propose to use a nested SmPL disjunction for desired adjustments.
> I suggest to start a corresponding case distinction behind
> the key word “return” instead of repeating it three times.
It doesn't work.
Thanks,
Denis
On 8/14/20 3:30 PM, Markus Elfring wrote:
>>> You propose to use a nested SmPL disjunction for desired adjustments.
>>> I suggest to start a corresponding case distinction behind
>>> the key word “return” instead of repeating it three times.
>>
>> It doesn't work.
>
> How do you think about to apply a SmPL rule variant like the following?
>
> @rp depends on patch@
> identifier show, dev, attr, buf;
> constant str;
> @@
>
> ssize_t show(struct device *dev, struct device_attribute *attr, char *buf)
> {
> <...
> return
> (
> - snprintf
> + sprintf
> (
> buf,
> - \(PAGE_SIZE\|PAGE_SIZE - 1\),
> ( str
> |
> ( "%i"\|"%i\n"\|"%li"\|"%li\n"\|"%lli"\|"%lli\n"\|
> "%d"\|"%d\n"\|"%ld"\|"%ld\n"\|"%lld"\|"%lld\n"\|
> "%u"\|"%u\n"\|"%lu"\|"%lu\n"\|"%llu"\|"%llu\n"\|
> "%x"\|"%x\n"\|"%lx"\|"%lx\n"\|"%llx"\|"%llx\n"\|
> "%X"\|"%X\n"\|"%lX"\|"%lX\n"\|"%llX"\|"%llX\n"\|
> "0x%x"\|"0x%x\n"\|"0x%lx"\|"0x%lx\n"\|"0x%llx"\|"0x%llx\n"\|
> "0x%X"\|"0x%X\n"\|"0x%lX"\|"0x%lX\n"\|"0x%llX"\|"0x%llX\n"\|
> "%02x\n"\|"%03x\n"\|"%04x\n"\|"%08x\n"\|
> "%02X\n"\|"%03X\n"\|"%04X\n"\|"%08X\n"\|
> "0x%02x\n"\|"0x%03x\n"\|"0x%04x\n"\|"0x%08x\n"\|
> "0x%02X\n"\|"0x%03X\n"\|"0x%04X\n"\|"0x%08X\n"\|
> "%zd"\|"%zd\n"\|"%zu"\|"%zu\n"\|"%zx"\|"%zx\n"\|
> "%c"\|"%c\n"\|"%p"\|"%p\n"\|"%pU\n"\|"%pUl\n"\|"%hu\n"
> ) ,
> ...
> )
> )
> |
> - snprintf
> + scnprintf
> (...)
> );
> ...>
> }
>
3 levels of nested disjunctions makes this pattern completely unreadable
and gives no comparable benefits. I don't think we should care much about
number of characters in the kernel sources, gzip will do a better job
anyway.
Thanks,
Denis