[Cocci] Need help with Python again

[Timur Tabi]

I'm trying to write a rule that will remove __FUNCTION__ from
printf-like statements. That is:

NV_PRINTF(x, "%s: ...", __FUNCTION__, ...)

into

NV_PRINTF(x, "...", ...)

I have this, which is based on existing Python code that works, but I
can't even get it to compile:

@script:python s@
c << r.c;
c2;
@@
import re

print c, c.find('%s')
coccinelle.c2 = c

// Get rid of __FUNCTION__ at the beginning of the string
@@
expression list[r.n] r.es;
constant char[] r.c;
identifier s.c2;
@@
NV_PRINTF(es,
-c, __FUNCTION__
+c2
,...);

This produces:

23 24
Fatal error: exception Failure("scriptmeta: parse error: \n = File
\"/home/ttabi/nv_printf2.cocci\", line 2, column 5, charpos = 23\n
around = 'r', whole content = c << r.c;\n")

Besides whatever is wrong with the script, I'm confused as to how
spatch knows to invoke the Python script in the first place. What is
it about my unnamed rule that tells spatch to invoke the script?

Also, why is the first parameter (es) an expression list? Can't I
just use "expression x;" instead?

[Timur Tabi]

Ok, I just noticed something in my original Python that I don't
understand. There are two clauses:

// Use Python to clean up the string literals.
// Comments are still C-style though
@r depends on rules@
constant char[] c;
expression list[n] es;
@@

NV_PRINTF(es,c,...)

@script:python s@
c << r.c;
c2;
@@
[snip]
coccinelle.c2 = c

@@
expression list[r.n] r.es;
constant char[] r.c;
identifier s.c2;
@@
NV_PRINTF(es,
-c
+c2
,...)

What is the third rule for?

Post by Timur Tabi
I'm trying to write a rule that will remove __FUNCTION__ from
NV_PRINTF(x, "%s: ...", __FUNCTION__, ...)
into
NV_PRINTF(x, "...", ...)
I have this, which is based on existing Python code that works, but I
@script:python s@
c << r.c;
c2;
@@
import re
print c, c.find('%s')
coccinelle.c2 = c
// Get rid of __FUNCTION__ at the beginning of the string
@@
expression list[r.n] r.es;
constant char[] r.c;
identifier s.c2;
@@
NV_PRINTF(es,
-c, __FUNCTION__
+c2
,...);
23 24
Fatal error: exception Failure("scriptmeta: parse error: \n = File
\"/home/ttabi/nv_printf2.cocci\", line 2, column 5, charpos = 23\n
around = 'r', whole content = c << r.c;\n")
Besides whatever is wrong with the script, I'm confused as to how
spatch knows to invoke the Python script in the first place. What is
it about my unnamed rule that tells spatch to invoke the script?
Also, why is the first parameter (es) an expression list? Can't I
just use "expression x;" instead?

[Julia Lawall]

Post by Timur Tabi
Ok, I just noticed something in my original Python that I don't
// Use Python to clean up the string literals.
// Comments are still C-style though
@r depends on rules@
constant char[] c;
expression list[n] es;
@@
NV_PRINTF(es,c,...)
@script:python s@
c << r.c;
c2;
@@
[snip]
coccinelle.c2 = c
@@
expression list[r.n] r.es;
constant char[] r.c;
identifier s.c2;
@@
NV_PRINTF(es,
-c
+c2
,...)
What is the third rule for?

The first rule finds the format string in the call to NV_PRINTF, the
second rule changes that, and the third rule replaces the old format
string by the new one.

If you know that there is always only one argument before the format
string, then you can use expression x instead of the expression list.

julia

Post by Timur Tabi

Post by Timur Tabi
I'm trying to write a rule that will remove __FUNCTION__ from
NV_PRINTF(x, "%s: ...", __FUNCTION__, ...)
into
NV_PRINTF(x, "...", ...)
I have this, which is based on existing Python code that works, but I
@script:python s@
c << r.c;
c2;
@@
import re
print c, c.find('%s')
coccinelle.c2 = c
// Get rid of __FUNCTION__ at the beginning of the string
@@
expression list[r.n] r.es;
constant char[] r.c;
identifier s.c2;
@@
NV_PRINTF(es,
-c, __FUNCTION__
+c2
,...);
23 24
Fatal error: exception Failure("scriptmeta: parse error: \n = File
\"/home/ttabi/nv_printf2.cocci\", line 2, column 5, charpos = 23\n
around = 'r', whole content = c << r.c;\n")
Besides whatever is wrong with the script, I'm confused as to how
spatch knows to invoke the Python script in the first place. What is
it about my unnamed rule that tells spatch to invoke the script?
Also, why is the first parameter (es) an expression list? Can't I
just use "expression x;" instead?

_______________________________________________
Cocci mailing list
https://systeme.lip6.fr/mailman/listinfo/cocci

[Julia Lawall]

Post by Timur Tabi
I'm trying to write a rule that will remove __FUNCTION__ from
NV_PRINTF(x, "%s: ...", __FUNCTION__, ...)
into
NV_PRINTF(x, "...", ...)
I have this, which is based on existing Python code that works, but I
@script:python s@
c << r.c;
c2;
@@
import re
print c, c.find('%s')
coccinelle.c2 = c
// Get rid of __FUNCTION__ at the beginning of the string
@@
expression list[r.n] r.es;
constant char[] r.c;
identifier s.c2;
@@
NV_PRINTF(es,
-c, __FUNCTION__
+c2
,...);
23 24
Fatal error: exception Failure("scriptmeta: parse error: \n = File
\"/home/ttabi/nv_printf2.cocci\", line 2, column 5, charpos = 23\n
around = 'r', whole content = c << r.c;\n")

It always checks the metavariables when parsing the semantic patch. That
doesn't involve invoking the python code. It looks like you are missing
the rule r, although I don't know if you have given the complete semantic
patch above.

julia

Post by Timur Tabi
Besides whatever is wrong with the script, I'm confused as to how
spatch knows to invoke the Python script in the first place. What is
it about my unnamed rule that tells spatch to invoke the script?
Also, why is the first parameter (es) an expression list? Can't I
just use "expression x;" instead?
_______________________________________________
Cocci mailing list
https://systeme.lip6.fr/mailman/listinfo/cocci