top: another scripting improvement

function                                             old     new   delta
handle_input                                         492     493      +1

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 27 insertions, 16 deletions

diff --git a/procps/top.c b/procps/top.c
index ed8b56173..c46797e78 100644
--- a/procps/top.c
+++ b/procps/top.c
@@ -856,24 +856,22 @@ enum {
 #if ENABLE_FEATURE_USE_TERMIOS
 static unsigned handle_input(unsigned scan_mask, unsigned interval)
 {
-        unsigned char c, *p, buf[64];
-        int len;
+        unsigned char c;
         struct pollfd pfd[1];
 
         pfd[0].fd = 0;
         pfd[0].events = POLLIN;
-        if (safe_poll(pfd, 1, interval * 1000) <= 0)
-                return scan_mask;
 
-        len = safe_read(STDIN_FILENO, &buf, sizeof(buf)-1);
-        if (len <= 0) { /* error/EOF? */
-                option_mask32 |= OPT_EOF;
-                return scan_mask;
-        }
+        while (1) {
+                if (safe_poll(pfd, 1, interval * 1000) <= 0)
+                        return scan_mask;
+                interval = 0;
+
+                if (safe_read(STDIN_FILENO, &c, 1) != 1) { /* error/EOF? */
+                        option_mask32 |= OPT_EOF;
+                        return scan_mask;
+                }
 
-        buf[len] = 0;
-        p = buf;
-        while ((c = *p++) != 0) {
                 if (c == initial_settings.c_cc[VINTR])
                         return EXIT_MASK;
                 if (c == initial_settings.c_cc[VEOF])
@@ -881,9 +879,11 @@ static unsigned handle_input(unsigned scan_mask, unsigned interval)
                 c |= 0x20; /* lowercase */
                 if (c == 'q')
                         return EXIT_MASK;
+
                 if (c == 'n') {
                         IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
                         sort_function[0] = pid_sort;
+                        continue;
                 }
                 if (c == 'm') {
                         IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
@@ -892,12 +892,14 @@ static unsigned handle_input(unsigned scan_mask, unsigned interval)
                         sort_function[1] = pcpu_sort;
                         sort_function[2] = time_sort;
 # endif
+                        continue;
                 }
 # if ENABLE_FEATURE_SHOW_THREADS
                 if (c == 'h'
                  IF_FEATURE_TOPMEM(&& scan_mask != TOPMEM_MASK)
                 ) {
                         scan_mask ^= PSSCAN_TASKS;
+                        continue;
                 }
 # endif
 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
@@ -906,12 +908,14 @@ static unsigned handle_input(unsigned scan_mask, unsigned interval)
                         sort_function[0] = pcpu_sort;
                         sort_function[1] = mem_sort;
                         sort_function[2] = time_sort;
+                        continue;
                 }
                 if (c == 't') {
                         IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
                         sort_function[0] = time_sort;
                         sort_function[1] = mem_sort;
                         sort_function[2] = pcpu_sort;
+                        continue;
                 }
 #  if ENABLE_FEATURE_TOPMEM
                 if (c == 's') {
@@ -920,10 +924,13 @@ static unsigned handle_input(unsigned scan_mask, unsigned interval)
                         prev_hist = NULL;
                         prev_hist_count = 0;
                         sort_field = (sort_field + 1) % NUM_SORT_FIELD;
+                        continue;
                 }
 #  endif
-                if (c == 'r')
+                if (c == 'r') {
                         inverted ^= 1;
+                        continue;
+                }
 #  if ENABLE_FEATURE_TOP_SMP_CPU
                 /* procps-2.0.18 uses 'C', 3.2.7 uses '1' */
                 if (c == 'c' || c == '1') {
@@ -940,9 +947,11 @@ static unsigned handle_input(unsigned scan_mask, unsigned interval)
                         num_cpus = 0;
                         smp_cpu_info = !smp_cpu_info;
                         get_jiffy_counts();
+                        continue;
                 }
 #  endif
 # endif
+                break; /* unknown key -> force refresh */
         }
 
         return scan_mask;
@@ -991,7 +1000,9 @@ static unsigned handle_input(unsigned scan_mask, unsigned interval)
  * echo sss | ./busybox top
  * - shows memory screen
  * echo sss | ./busybox top -bn1 >mem
- * - saves memory screen - the *whole* list, not first NROWS porcesses!
+ * - saves memory screen - the *whole* list, not first NROWS processes!
+ * echo .m.s.s.s.s.s.s.q | ./busybox top -b >z
+ * - saves several different screens, and exits
  *
  * TODO: -i STRING param as a better alternative?
  */
@@ -1165,8 +1176,8 @@ int top_main(int argc UNUSED_PARAM, char **argv)
 #if !ENABLE_FEATURE_USE_TERMIOS
                 sleep(interval);
 #else
-                if (option_mask32 & (OPT_b|OPT_EOF))
-                         /* batch mode, or EOF on stdin ("top </dev/null") */
+                if (option_mask32 & OPT_EOF)
+                        /* EOF on stdin ("top </dev/null") */
                         sleep(interval);
                 else
                         scan_mask = handle_input(scan_mask, interval);