*: s/BB_SIGS_FATAL/BB_FATAL_SIGS/ (latter proved easier to remember)
top: fix "top </dev/null" case (by Cristian Ionescu-Idbohrn)
diff --git a/procps/top.c b/procps/top.c
index fdd7584..85ceacc 100644
--- a/procps/top.c
+++ b/procps/top.c
@@ -108,8 +108,13 @@
#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 @@
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 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 @@
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 @@
/* 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 @@
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 @@
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 @@
#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 @@
#endif
}
#endif /* FEATURE_USE_TERMIOS */
- }
+ } /* end of "while (1)" */
+
bb_putchar('\n');
+ reset_term();
return EXIT_SUCCESS;
}