tftp: fix bad interaction betweel poll() and alarm(). Closes bug 3061

This was breaking timeout handling.

function                                             old     new   delta
tftp_progress_update                                   -      45     +45
tftp_progress_done                                     -      32     +32
tftp_protocol                                       1839    1858     +19
tftp_progress_init                                     9      15      +6
tftp_main                                            298     286     -12
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 2/1 up/down: 102/-12)            Total: 90 bytes

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

1 files changed, 12 insertions, 27 deletions

diff --git a/networking/tftp.c b/networking/tftp.c
index 04c8f0ebb..fcd933f6a 100644
--- a/networking/tftp.c
+++ b/networking/tftp.c
@@ -105,39 +105,22 @@ struct BUG_G_too_big {
 #define error_pkt_str    (error_pkt + 4)
 
 #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
-/* SIGALRM logic nicked from the wget applet */
-static void progress_meter(int flag)
+static void tftp_progress_update(void)
 {
-	/* We can be called from signal handler */
-	int save_errno = errno;
-
-	if (flag == -1) { /* first call to progress_meter */
-		bb_progress_init(&G.pmt);
-	}
-
 	bb_progress_update(&G.pmt, G.file, 0, G.pos, G.size);
-
-	if (flag == 0) {
-		/* last call to progress_meter */
-		alarm(0);
-		bb_putchar_stderr('\n');
-	} else {
-		if (flag == -1) { /* first call to progress_meter */
-			signal_SA_RESTART_empty_mask(SIGALRM, progress_meter);
-		}
-		alarm(1);
-	}
-
-	errno = save_errno;
 }
 static void tftp_progress_init(void)
 {
-	progress_meter(-1);
+	bb_progress_init(&G.pmt);
+	tftp_progress_update();
 }
 static void tftp_progress_done(void)
 {
-	if (G.pmt.inited)
-		progress_meter(0);
+	if (G.pmt.inited) {
+		tftp_progress_update();
+		bb_putchar_stderr('\n');
+		G.pmt.inited = 0;
+	}
 }
 #else
 # define tftp_progress_init() ((void)0)
@@ -460,9 +443,10 @@ static int tftp_protocol(
 		xsendto(socket_fd, xbuf, send_len, &peer_lsa->u.sa, peer_lsa->len);
 
 #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
-		if (ENABLE_TFTP && remote_file) { /* tftp */
+		if (ENABLE_TFTP && remote_file) /* tftp */
 			G.pos = (block_nr - 1) * (uoff_t)blksize;
-		}
+		if (G.pmt.inited)
+			tftp_progress_update();
 #endif
 		/* Was it final ACK? then exit */
 		if (finished && (opcode == TFTP_ACK))
@@ -479,6 +463,7 @@ static int tftp_protocol(
 		case 0:
 			retries--;
 			if (retries == 0) {
+				tftp_progress_done();
 				bb_error_msg("timeout");
 				goto ret; /* no err packet sent */
 			}