perf syscalltbl: Support glob matching on syscall names

With two new methods, one to find the first match, returning its syscall
id and its index in whatever internal database it keeps the syscall
into, then one to find the next match, if any.

Implemented only on arches where we actually read the syscall table from
the kernel sources, i.e. x86-64 for now, all the others use the libaudit
method for which this returns -1, i.e. just stubs were added, with the
actual implementation using whatever libaudit functions for matching
that may be available.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-i0sj4rxk1a63pfe9gl8z8irs@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/syscalltbl.c

@@ -19,6 +19,7 @@
 #ifdef HAVE_SYSCALL_TABLE
 #include <linux/compiler.h>
 #include <string.h>
+#include "string2.h"
 #include "util.h"
 
 #if defined(__x86_64__)
@@ -105,6 +106,27 @@ int syscalltbl__id(struct syscalltbl *tbl, const char *name)
 	return sc ? sc->id : -1;
 }
 
+int syscalltbl__strglobmatch_next(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
+{
+	int i;
+	struct syscall *syscalls = tbl->syscalls.entries;
+
+	for (i = *idx + 1; i < tbl->syscalls.nr_entries; ++i) {
+		if (strglobmatch(syscalls[i].name, syscall_glob)) {
+			*idx = i;
+			return syscalls[i].id;
+		}
+	}
+
+	return -1;
+}
+
+int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
+{
+	*idx = -1;
+	return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
+}
+
 #else /* HAVE_SYSCALL_TABLE */
 
 #include <libaudit.h>
@@ -131,4 +153,15 @@ int syscalltbl__id(struct syscalltbl *tbl, const char *name)
 {
 	return audit_name_to_syscall(name, tbl->audit_machine);
 }
+
+int syscalltbl__strglobmatch_next(struct syscalltbl *tbl __maybe_unused,
+				  const char *syscall_glob __maybe_unused, int *idx __maybe_unused)
+{
+	return -1;
+}
+
+int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
+{
+	return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
+}
 #endif /* HAVE_SYSCALL_TABLE */

tools/perf/util/syscalltbl.h

@@ -17,4 +17,7 @@ void syscalltbl__delete(struct syscalltbl *tbl);
 const char *syscalltbl__name(const struct syscalltbl *tbl, int id);
 int syscalltbl__id(struct syscalltbl *tbl, const char *name);
 
+int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx);
+int syscalltbl__strglobmatch_next(struct syscalltbl *tbl, const char *syscall_glob, int *idx);
+
 #endif /* __PERF_SYSCALLTBL_H */