On Tue, Apr 26, 2016 at 11:24:43AM -0400, Valdis.Kletnieks@vt.edu wrote:
On Tue, 26 Apr 2016 15:31:51 +0200, Silvan Jegen said:
A simple but naive approach would be a grep command like this.
grep "function_pointer =" `find . -iname '*.c' -o -iname '*.h'`
Two better ways:
grep -r "function_pointer =' [A-Za-z]*
find * -name '*.[ch]' | xargs grep 'function pointer ='
Hint 1: Globbing * rather than . is a win at the top level of the kernel source, because * won't match .git, which is a gigabyte or so of stuff that you don't want to grep through
Good idea! There may also be cases where there is no space before the assignment so using a regexp like this may be better. grep 'function_pointer ?='
Hint 2: You want -name rather than -iname because there shouldn't be any *.C or *.H files in the tree, and avoiding case-insensitive matches is a bit faster.
True, this was mostly muscle memory.
And another winner if you have a git tree (which of course you should):
git grep 'function_pointer ='
Looks useful but I hope they did not implement their own version of grep...
One gotcha is that in some places, the kernel does evil pre-processor stuff like:
#define ATOMIC_LONG_INIT(i) ATOMIC_INIT(i) #define ATOMIC_LONG_PFX(x) atomic ## x
#endif
#define ATOMIC_LONG_READ_OP(mo) static inline long atomic_long_read##mo(const atomic_long_t *l) { ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; return (long)ATOMIC_LONG_PFX(_read##mo)(v); } ATOMIC_LONG_READ_OP() ATOMIC_LONG_READ_OP(_acquire)
(this example from include/asm-generic/atomic-long.h, but similar ## abuse happens elsewhere as well...)
Yeah, I don't think there is much you can do about these cases... Cheers, Silvan