read_key: drop optimization where we read 3 bytes at once

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index a0b1bcf8e..81f6fdeff 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -1451,10 +1451,13 @@ static int lineedit_read_key(char *read_key_buffer)
         pfd.events = POLLIN;
         do {
  poll_again:
-                /* Wait for input. Can't just call read_key, it will return
-                 * at once if stdin is in non-blocking mode. */
-                safe_poll(&pfd, 1, -1);
-                /* note: read_key sets errno to 0 on success: */
+                if (read_key_buffer[0] == 0) {
+                        /* Wait for input. Can't just call read_key,
+                         * it returns at once if stdin
+                         * is in non-blocking mode. */
+                        safe_poll(&pfd, 1, -1);
+                }
+                /* Note: read_key sets errno to 0 on success: */
                 ic = read_key(STDIN_FILENO, read_key_buffer);
                 if (ENABLE_FEATURE_EDITING_ASK_TERMINAL
                  && (int32_t)ic == KEYCODE_CURSOR_POS