tools lib string: Adopt prefixcmp() from perf and subcmd

Both had copies originating from git.git, move those to
tools/lib/string.c, getting both tools/lib/subcmd/ and tools/perf/ to
use it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-uidwtticro1qhttzd2rkrkg1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 0 insertions, 11 deletions

diff --git a/tools/perf/util/strbuf.c b/tools/perf/util/strbuf.c
index e91b5e86f027..aafe908b82b5 100644
--- a/tools/perf/util/strbuf.c
+++ b/tools/perf/util/strbuf.c
@@ -3,15 +3,6 @@
 #include <linux/kernel.h>
 #include <errno.h>
 
-int prefixcmp(const char *str, const char *prefix)
-{
-        for (; ; str++, prefix++)
-                if (!*prefix)
-                        return 0;
-                else if (*str != *prefix)
-                        return (unsigned char)*prefix - (unsigned char)*str;
-}
-
 /*
  * Used as the default ->buf value, so that people can always assume
  * buf is non NULL and ->buf is NUL terminated even for a freshly
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index d620719775a8..5dfb9bb6482d 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -30,8 +30,6 @@ void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 
 void set_warning_routine(void (*routine)(const char *err, va_list params));
 
-int prefixcmp(const char *str, const char *prefix);
-
 static inline void *zalloc(size_t size)
 {
         return calloc(1, size);