microcom: read more than 1 byte from device, if possible

1 files changed, 16 insertions, 14 deletions

diff --git a/miscutils/microcom.c b/miscutils/microcom.c
index 817ef55ac..63b07fd69 100644
--- a/miscutils/microcom.c
+++ b/miscutils/microcom.c
@@ -63,7 +63,7 @@ int microcom_main(int argc, char **argv)
         char *opt_d;
         char *opt_t;
         unsigned opts;
-        opt_complementary = "=1"; /* exactly one arg should be there */
+        opt_complementary = "=1"; // exactly one arg should be there
         opts = getopt32(argv, "Xs:d:t:", &opt_s, &opt_d, &opt_t);
 
         // apply options
@@ -141,36 +141,38 @@ int microcom_main(int argc, char **argv)
         signalled = 0;
         nfd = 2;
         while (!signalled && safe_poll(pfd, nfd, timeout) > 0) {
-                char c;
-                if (pfd[0].revents) {
-serial_ready:
-                        // read from device -> write to stdout
-                        if (safe_read(sfd, &c, 1) > 0)
-                                write(STDOUT_FILENO, &c, 1);
-                        // else { EOF/error - what to do? }
-                }
                 if (pfd[1].revents) {
-                        pfd[1].revents = 0;
+                        char c;
                         // read from stdin -> write to device
                         if (safe_read(STDIN_FILENO, &c, 1) < 1) {
                                 // don't poll stdin anymore if we got EOF/error
+                                pfd[1].revents = 0;
                                 nfd--;
-                                continue;
+                                goto check_stdin;
                         }
                         // do we need special processing?
                         if (!(opts & OPT_X)) {
                                 // ^@ sends Break
                                 if (VINTR == c) {
                                         tcsendbreak(sfd, 0);
-                                        continue;
+                                        goto check_stdin;
                                 }
                                 // ^X exits
                                 if (24 == c)
                                         break;
                         }
                         write(sfd, &c, 1);
-                        if (delay >= 0 && safe_poll(pfd, 1, delay) > 0)
-                                goto serial_ready;
+                        if (delay >= 0)
+                                safe_poll(pfd, 1, delay);
+                }
+check_stdin:
+                if (pfd[0].revents) {
+                        ssize_t len;
+                        // read from device -> write to stdout
+                        len = safe_read(sfd, bb_common_bufsiz1, sizeof(bb_common_bufsiz1));
+                        if (len > 0)
+                                full_write(STDOUT_FILENO, bb_common_bufsiz1, len);
+                        // else { EOF/error - what to do? }
                 }
         }