libperf: Adopt the readn()/writen() functions from tools/perf

Move the readn()/writen() functions into libperf.

Keep those non-namespaced names because they will be shared only between
perf and libperf.

Again, these are not exported functions.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190721112506.12306-61-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 0 insertions, 40 deletions

diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index a61535cf1bca..9c3c97697387 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -384,46 +384,6 @@ int copyfile(const char *from, const char *to)
         return copyfile_mode(from, to, 0755);
 }
 
-static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
-{
-        void *buf_start = buf;
-        size_t left = n;
-
-        while (left) {
-                /* buf must be treated as const if !is_read. */
-                ssize_t ret = is_read ? read(fd, buf, left) :
-                                        write(fd, buf, left);
-
-                if (ret < 0 && errno == EINTR)
-                        continue;
-                if (ret <= 0)
-                        return ret;
-
-                left -= ret;
-                buf  += ret;
-        }
-
-        BUG_ON((size_t)(buf - buf_start) != n);
-        return n;
-}
-
-/*
- * Read exactly 'n' bytes or return an error.
- */
-ssize_t readn(int fd, void *buf, size_t n)
-{
-        return ion(true, fd, buf, n);
-}
-
-/*
- * Write exactly 'n' bytes or return an error.
- */
-ssize_t writen(int fd, const void *buf, size_t n)
-{
-        /* ion does not modify buf. */
-        return ion(false, fd, (void *)buf, n);
-}
-
 size_t hex_width(u64 v)
 {
         size_t n = 1;