5 files changed, 34 insertions, 24 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 654643743..d059ac9de 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -278,7 +278,7 @@ char *xmalloc_follow_symlinks(const char *path);
 
 
 enum {
-        /* bb_signals(BB_SIGS_FATAL, handler) catches all signals which
+        /* bb_signals(BB_FATAL_SIGS, handler) catches all signals which
          * otherwise would kill us, except for those resulting from bugs:
          * SIGSEGV, SIGILL, SIGFPE.
          * Other fatal signals not included (TODO?):
@@ -288,7 +288,7 @@ enum {
          * SIGSYS   Bad argument to routine
          * SIGTRAP  Trace/breakpoint trap
          */
-        BB_SIGS_FATAL = 0
+        BB_FATAL_SIGS = 0
                 + (1 << SIGHUP)
                 + (1 << SIGINT)
                 + (1 << SIGTERM)
diff --git a/miscutils/less.c b/miscutils/less.c
index 3a9dea039..1a67ca7ce 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -1400,7 +1400,7 @@ int less_main(int argc, char **argv)
         term_less.c_cc[VTIME] = 0;
 
         /* We want to restore term_orig on exit */
-        bb_signals(BB_SIGS_FATAL, sig_catcher);
+        bb_signals(BB_FATAL_SIGS, sig_catcher);
 
         reinitialize();
         while (1) {
diff --git a/miscutils/watchdog.c b/miscutils/watchdog.c
index 7fb16b861..a5061f5d7 100644
--- a/miscutils/watchdog.c
+++ b/miscutils/watchdog.c
@@ -46,7 +46,7 @@ int watchdog_main(int argc, char **argv)
                 bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
         }
 
-        bb_signals(BB_SIGS_FATAL, watchdog_shutdown);
+        bb_signals(BB_FATAL_SIGS, watchdog_shutdown);
 
         /* Use known fd # - avoid needing global 'int fd' */
         xmove_fd(xopen(argv[argc - 1], O_WRONLY), 3);
diff --git a/networking/tcpudp.c b/networking/tcpudp.c
index f97787497..5da4de505 100644
--- a/networking/tcpudp.c
+++ b/networking/tcpudp.c
@@ -264,7 +264,7 @@ int tcpudpsvd_main(int argc ATTRIBUTE_UNUSED, char **argv)
 
         sig_block(SIGCHLD);
         signal(SIGCHLD, sig_child_handler);
-        bb_signals(BB_SIGS_FATAL, sig_term_handler);
+        bb_signals(BB_FATAL_SIGS, sig_term_handler);
         signal(SIGPIPE, SIG_IGN);
 
         if (max_per_host)
diff --git a/procps/top.c b/procps/top.c
index fdd7584c8..85ceaccf7 100644
--- a/procps/top.c
+++ b/procps/top.c
@@ -108,8 +108,13 @@ enum { LINE_BUF_SIZE = COMMON_BUFSIZE - offsetof(struct globals, line_buf) };
 #define total_pcpu       (G.total_pcpu        )
 #define line_buf         (G.line_buf          )
 
-
-#define OPT_BATCH_MODE (option_mask32 & 0x4)
+enum {
+        OPT_d = (1 << 0),
+        OPT_n = (1 << 1),
+        OPT_b = (1 << 2),
+        OPT_EOF = (1 << 3), /* pseudo: "we saw EOF in stdin" */
+};
+#define OPT_BATCH_MODE (option_mask32 & OPT_b)
 
 
 #if ENABLE_FEATURE_USE_TERMIOS
@@ -165,7 +170,7 @@ static void get_jiffy_counts(void)
         if (fscanf(fp, "cpu  %lld %lld %lld %lld %lld %lld %lld %lld",
                         &jif.usr,&jif.nic,&jif.sys,&jif.idle,
                         &jif.iowait,&jif.irq,&jif.softirq,&jif.steal) < 4) {
-                bb_error_msg_and_die("failed to read /proc/stat");
+                bb_error_msg_and_die("can't read /proc/stat");
         }
         fclose(fp);
         jif.total = jif.usr + jif.nic + jif.sys + jif.idle
@@ -506,7 +511,7 @@ static void clearmems(void)
 
 static void reset_term(void)
 {
-        tcsetattr(0, TCSANOW, (void *) &initial_settings);
+        tcsetattr(0, TCSANOW, &initial_settings);
         if (ENABLE_FEATURE_CLEAN_UP) {
                 clearmems();
 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
@@ -753,13 +758,13 @@ int top_main(int argc ATTRIBUTE_UNUSED, char **argv)
 
         INIT_G();
 
-        interval = 5; /* default update rate is 5 seconds */
+        interval = 5; /* default update interval is 5 seconds */
         iterations = 0; /* infinite */
 
-        /* do normal option parsing */
+        /* all args are options; -n NUM */
         opt_complementary = "-:n+";
         getopt32(argv, "d:n:b", &sinterval, &iterations);
-        if (option_mask32 & 0x1) {
+        if (option_mask32 & OPT_d) {
                 /* Need to limit it to not overflow poll timeout */
                 interval = xatou16(sinterval); // -d
         }
@@ -772,12 +777,8 @@ int top_main(int argc ATTRIBUTE_UNUSED, char **argv)
         /* unbuffered input, turn off echo */
         new_settings.c_lflag &= ~(ISIG | ICANON | ECHO | ECHONL);
 
-        bb_signals(0
-                + (1 << SIGTERM)
-                + (1 << SIGINT)
-                , sig_catcher);
+        bb_signals(BB_FATAL_SIGS, sig_catcher);
         tcsetattr(0, TCSANOW, (void *) &new_settings);
-        atexit(reset_term);
 #endif /* FEATURE_USE_TERMIOS */
 
 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
@@ -794,7 +795,8 @@ int top_main(int argc ATTRIBUTE_UNUSED, char **argv)
                 lines = 24; /* default */
                 col = 79;
 #if ENABLE_FEATURE_USE_TERMIOS
-                get_terminal_width_height(0, &col, &lines);
+                /* We output to stdout, we need size of stdout (not stdin)! */
+                get_terminal_width_height(STDOUT_FILENO, &col, &lines);
                 if (lines < 5 || col < 10) {
                         sleep(interval);
                         continue;
@@ -839,9 +841,10 @@ int top_main(int argc ATTRIBUTE_UNUSED, char **argv)
                                 topmem[n].stack    = p->stack;
 #endif
                         }
-                }
+                } /* end of "while we read /proc" */
                 if (ntop == 0) {
-                        bb_error_msg_and_die("no process info in /proc");
+                        bb_error_msg("no process info in /proc");
+                        break;
                 }
 
                 if (scan_mask == TOP_MASK) {
@@ -875,9 +878,14 @@ int top_main(int argc ATTRIBUTE_UNUSED, char **argv)
 #if !ENABLE_FEATURE_USE_TERMIOS
                 sleep(interval);
 #else
-                if (safe_poll(pfd, 1, interval * 1000) > 0) {
-                        if (read(0, &c, 1) != 1)    /* signal */
-                                break;
+                if (option_mask32 & (OPT_b|OPT_EOF))
+                         /* batch mode, or EOF on stdin ("top </dev/null") */
+                        sleep(interval);
+                else if (safe_poll(pfd, 1, interval * 1000) > 0) {
+                        if (safe_read(0, &c, 1) != 1) { /* error/EOF? */
+                                option_mask32 |= OPT_EOF;
+                                continue;
+                        }
                         if (c == initial_settings.c_cc[VINTR])
                                 break;
                         c |= 0x20; /* lowercase */
@@ -922,7 +930,9 @@ int top_main(int argc ATTRIBUTE_UNUSED, char **argv)
 #endif
                 }
 #endif /* FEATURE_USE_TERMIOS */
-        }
+        } /* end of "while (1)" */
+
         bb_putchar('\n');
+        reset_term();
         return EXIT_SUCCESS;
 }