From b308d81e927d28cb0223378049defc133787727d Mon Sep 17 00:00:00 2001
From: Denis Vlasenko <vda.linux@googlemail.com>
Date: Tue, 28 Aug 2007 19:35:34 +0000
Subject: top: use poll instead of select for waiting on one descriptor
smart_ulltoa5: make it more cryptic. -50 bytes.
function old new delta
passwd_main 1095 1103 +8
getNum 557 565 +8
buffer_fill_and_print 73 76 +3
udhcpc_main 2393 2395 +2
mkfs_minix_main 3071 3070 -1
dname_enc 377 373 -4
expmeta 480 472 -8
smart_ulltoa5 334 283 -51
top_main 911 815 -96
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/5 up/down: 21/-160) Total: -139 bytes
text data bss dec hex filename
770872 1063 10788 782723 bf183 busybox_old
770732 1063 10788 782583 bf0f7 busybox_unstripped
---
procps/top.c | 39 +++++++++++++++++++--------------------
1 file changed, 19 insertions(+), 20 deletions(-)
(limited to 'procps')
diff --git a/procps/top.c b/procps/top.c
index c02a959e0..abc7a4363 100644
--- a/procps/top.c
+++ b/procps/top.c
@@ -448,7 +448,7 @@ static void display_status(int count, int scr_width)
#endif
if (s->vsz >= 100*1024)
- sprintf(vsz_str_buf, "%6ldM", s->vsz/1024);
+ sprintf(vsz_str_buf, "%6ldm", s->vsz/1024);
else
sprintf(vsz_str_buf, "%7ld", s->vsz);
// PID PPID USER STAT VSZ %MEM [%CPU] COMMAND
@@ -519,23 +519,29 @@ int top_main(int argc, char **argv);
int top_main(int argc, char **argv)
{
int count, lines, col;
- unsigned interval = 5; /* default update rate is 5 seconds */
- unsigned iterations = UINT_MAX; /* 2^32 iterations by default :) */
+ unsigned interval;
+ int iterations = -1; /* infinite */
char *sinterval, *siterations;
#if ENABLE_FEATURE_USE_TERMIOS
struct termios new_settings;
- struct timeval tv;
- fd_set readfds;
+ struct pollfd pfd[1];
unsigned char c;
+
+ pfd[0].fd = 0;
+ pfd[0].events = POLLIN;
#endif /* FEATURE_USE_TERMIOS */
- interval = 5;
+ interval = 5; /* default update rate is 5 seconds */
/* do normal option parsing */
opt_complementary = "-";
getopt32(argv, "d:n:b", &sinterval, &siterations);
- if (option_mask32 & 0x1) interval = xatou(sinterval); // -d
- if (option_mask32 & 0x2) iterations = xatou(siterations); // -n
+ if (option_mask32 & 0x1) {
+ /* Need to limit it to not overflow poll timeout */
+ interval = xatou16(sinterval); // -d
+ }
+ if (option_mask32 & 0x2)
+ iterations = xatoi_u(siterations); // -n
//if (option_mask32 & 0x4) // -b
/* change to /proc */
@@ -584,9 +590,8 @@ int top_main(int argc, char **argv)
| PSSCAN_UTIME
| PSSCAN_STATE
| PSSCAN_COMM
- | PSSCAN_SID
| PSSCAN_UIDGID
- ))) {
+ )) != NULL) {
int n = ntop;
top = xrealloc(top, (++ntop) * sizeof(*top));
top[n].pid = p->pid;
@@ -622,15 +627,9 @@ int top_main(int argc, char **argv)
/* show status for each of the processes */
display_status(count, col);
#if ENABLE_FEATURE_USE_TERMIOS
- tv.tv_sec = interval;
- tv.tv_usec = 0;
- FD_ZERO(&readfds);
- FD_SET(0, &readfds);
- select(1, &readfds, NULL, NULL, &tv);
- if (FD_ISSET(0, &readfds)) {
- if (read(0, &c, 1) <= 0) { /* signal */
- return EXIT_FAILURE;
- }
+ if (poll(pfd, 1, interval * 1000) != 0) {
+ if (read(0, &c, 1) != 1) /* signal */
+ break;
if (c == 'q' || c == initial_settings.c_cc[VINTR])
break;
if (c == 'M') {
@@ -662,7 +661,7 @@ int top_main(int argc, char **argv)
#endif
}
}
- if (!--iterations)
+ if (iterations >= 0 && !--iterations)
break;
#else
sleep(interval);
--
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