*: suppress ~60% of "aliased warnings" on gcc-4.4.1
[platform/upstream/busybox.git] / procps / top.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * A tiny 'top' utility.
4  *
5  * This is written specifically for the linux /proc/<PID>/stat(m)
6  * files format.
7  *
8  * This reads the PIDs of all processes and their status and shows
9  * the status of processes (first ones that fit to screen) at given
10  * intervals.
11  *
12  * NOTES:
13  * - At startup this changes to /proc, all the reads are then
14  *   relative to that.
15  *
16  * (C) Eero Tamminen <oak at welho dot com>
17  *
18  * Rewritten by Vladimir Oleynik (C) 2002 <dzo@simtreas.ru>
19  *
20  * Sept 2008: Vineet Gupta <vineet.gupta@arc.com>
21  * Added Support for reporting SMP Information
22  * - CPU where Process was last seen running
23  *   (to see effect of sched_setaffinity() etc)
24  * - CPU Time Split (idle/IO/wait etc) PER CPU
25  *
26  * Copyright (c) 1992 Branko Lankester
27  * Copyright (c) 1992 Roger Binns
28  * Copyright (C) 1994-1996 Charles L. Blake.
29  * Copyright (C) 1992-1998 Michael K. Johnson
30  *
31  * Licensed under GPLv2, see file LICENSE in this tarball for details.
32  */
33
34 #include "libbb.h"
35
36
37 typedef struct top_status_t {
38         unsigned long vsz;
39 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
40         unsigned long ticks;
41         unsigned pcpu; /* delta of ticks */
42 #endif
43         unsigned pid, ppid;
44         unsigned uid;
45         char state[4];
46         char comm[COMM_LEN];
47 #if ENABLE_FEATURE_TOP_SMP_PROCESS
48         int last_seen_on_cpu;
49 #endif
50 } top_status_t;
51
52 typedef struct jiffy_counts_t {
53         /* Linux 2.4.x has only first four */
54         unsigned long long usr, nic, sys, idle;
55         unsigned long long iowait, irq, softirq, steal;
56         unsigned long long total;
57         unsigned long long busy;
58 } jiffy_counts_t;
59
60 /* This structure stores some critical information from one frame to
61    the next. Used for finding deltas. */
62 typedef struct save_hist {
63         unsigned long ticks;
64         pid_t pid;
65 } save_hist;
66
67 typedef int (*cmp_funcp)(top_status_t *P, top_status_t *Q);
68
69
70 enum { SORT_DEPTH = 3 };
71
72
73 struct globals {
74         top_status_t *top;
75         int ntop;
76 #if ENABLE_FEATURE_TOPMEM
77         smallint sort_field;
78         smallint inverted;
79 #endif
80 #if ENABLE_FEATURE_TOP_SMP_CPU
81         smallint smp_cpu_info; /* one/many cpu info lines? */
82 #endif
83 #if ENABLE_FEATURE_USE_TERMIOS
84         struct termios initial_settings;
85 #endif
86 #if !ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
87         cmp_funcp sort_function[1];
88 #else
89         cmp_funcp sort_function[SORT_DEPTH];
90         struct save_hist *prev_hist;
91         int prev_hist_count;
92         jiffy_counts_t cur_jif, prev_jif;
93         /* int hist_iterations; */
94         unsigned total_pcpu;
95         /* unsigned long total_vsz; */
96 #endif
97 #if ENABLE_FEATURE_TOP_SMP_CPU
98         /* Per CPU samples: current and last */
99         jiffy_counts_t *cpu_jif, *cpu_prev_jif;
100         int num_cpus;
101 #endif
102         char line_buf[80];
103 }; //FIX_ALIASING; - large code growth
104 enum { LINE_BUF_SIZE = COMMON_BUFSIZE - offsetof(struct globals, line_buf) };
105 #define G (*(struct globals*)&bb_common_bufsiz1)
106 #define INIT_G() do { \
107         struct G_sizecheck { \
108                 char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
109         }; \
110 } while (0)
111 #define top              (G.top               )
112 #define ntop             (G.ntop              )
113 #define sort_field       (G.sort_field        )
114 #define inverted         (G.inverted          )
115 #define smp_cpu_info     (G.smp_cpu_info      )
116 #define initial_settings (G.initial_settings  )
117 #define sort_function    (G.sort_function     )
118 #define prev_hist        (G.prev_hist         )
119 #define prev_hist_count  (G.prev_hist_count   )
120 #define cur_jif          (G.cur_jif           )
121 #define prev_jif         (G.prev_jif          )
122 #define cpu_jif          (G.cpu_jif           )
123 #define cpu_prev_jif     (G.cpu_prev_jif      )
124 #define num_cpus         (G.num_cpus          )
125 #define total_pcpu       (G.total_pcpu        )
126 #define line_buf         (G.line_buf          )
127
128 enum {
129         OPT_d = (1 << 0),
130         OPT_n = (1 << 1),
131         OPT_b = (1 << 2),
132         OPT_m = (1 << 3),
133         OPT_EOF = (1 << 4), /* pseudo: "we saw EOF in stdin" */
134 };
135 #define OPT_BATCH_MODE (option_mask32 & OPT_b)
136
137
138 #if ENABLE_FEATURE_USE_TERMIOS
139 static int pid_sort(top_status_t *P, top_status_t *Q)
140 {
141         /* Buggy wrt pids with high bit set */
142         /* (linux pids are in [1..2^15-1]) */
143         return (Q->pid - P->pid);
144 }
145 #endif
146
147 static int mem_sort(top_status_t *P, top_status_t *Q)
148 {
149         /* We want to avoid unsigned->signed and truncation errors */
150         if (Q->vsz < P->vsz) return -1;
151         return Q->vsz != P->vsz; /* 0 if ==, 1 if > */
152 }
153
154
155 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
156
157 static int pcpu_sort(top_status_t *P, top_status_t *Q)
158 {
159         /* Buggy wrt ticks with high bit set */
160         /* Affects only processes for which ticks overflow */
161         return (int)Q->pcpu - (int)P->pcpu;
162 }
163
164 static int time_sort(top_status_t *P, top_status_t *Q)
165 {
166         /* We want to avoid unsigned->signed and truncation errors */
167         if (Q->ticks < P->ticks) return -1;
168         return Q->ticks != P->ticks; /* 0 if ==, 1 if > */
169 }
170
171 static int mult_lvl_cmp(void* a, void* b)
172 {
173         int i, cmp_val;
174
175         for (i = 0; i < SORT_DEPTH; i++) {
176                 cmp_val = (*sort_function[i])(a, b);
177                 if (cmp_val != 0)
178                         return cmp_val;
179         }
180         return 0;
181 }
182
183 static NOINLINE int read_cpu_jiffy(FILE *fp, jiffy_counts_t *p_jif)
184 {
185 #if !ENABLE_FEATURE_TOP_SMP_CPU
186         static const char fmt[] = "cpu %llu %llu %llu %llu %llu %llu %llu %llu";
187 #else
188         static const char fmt[] = "cp%*s %llu %llu %llu %llu %llu %llu %llu %llu";
189 #endif
190         int ret;
191
192         if (!fgets(line_buf, LINE_BUF_SIZE, fp) || line_buf[0] != 'c' /* not "cpu" */)
193                 return 0;
194         ret = sscanf(line_buf, fmt,
195                         &p_jif->usr, &p_jif->nic, &p_jif->sys, &p_jif->idle,
196                         &p_jif->iowait, &p_jif->irq, &p_jif->softirq,
197                         &p_jif->steal);
198         if (ret >= 4) {
199                 p_jif->total = p_jif->usr + p_jif->nic + p_jif->sys + p_jif->idle
200                         + p_jif->iowait + p_jif->irq + p_jif->softirq + p_jif->steal;
201                 /* procps 2.x does not count iowait as busy time */
202                 p_jif->busy = p_jif->total - p_jif->idle - p_jif->iowait;
203         }
204
205         return ret;
206 }
207
208 static void get_jiffy_counts(void)
209 {
210         FILE* fp = xfopen_for_read("stat");
211
212         /* We need to parse cumulative counts even if SMP CPU display is on,
213          * they are used to calculate per process CPU% */
214         prev_jif = cur_jif;
215         if (read_cpu_jiffy(fp, &cur_jif) < 4)
216                 bb_error_msg_and_die("can't read /proc/stat");
217
218 #if !ENABLE_FEATURE_TOP_SMP_CPU
219         fclose(fp);
220         return;
221 #else
222         if (!smp_cpu_info) {
223                 fclose(fp);
224                 return;
225         }
226
227         if (!num_cpus) {
228                 /* First time here. How many CPUs?
229                  * There will be at least 1 /proc/stat line with cpu%d
230                  */
231                 while (1) {
232                         cpu_jif = xrealloc_vector(cpu_jif, 1, num_cpus);
233                         if (read_cpu_jiffy(fp, &cpu_jif[num_cpus]) <= 4)
234                                 break;
235                         num_cpus++;
236                 }
237                 if (num_cpus == 0) /* /proc/stat with only "cpu ..." line?! */
238                         smp_cpu_info = 0;
239
240                 cpu_prev_jif = xzalloc(sizeof(cpu_prev_jif[0]) * num_cpus);
241
242                 /* Otherwise the first per cpu display shows all 100% idles */
243                 usleep(50000);
244         } else { /* Non first time invocation */
245                 jiffy_counts_t *tmp;
246                 int i;
247
248                 /* First switch the sample pointers: no need to copy */
249                 tmp = cpu_prev_jif;
250                 cpu_prev_jif = cpu_jif;
251                 cpu_jif = tmp;
252
253                 /* Get the new samples */
254                 for (i = 0; i < num_cpus; i++)
255                         read_cpu_jiffy(fp, &cpu_jif[i]);
256         }
257 #endif
258         fclose(fp);
259 }
260
261 static void do_stats(void)
262 {
263         top_status_t *cur;
264         pid_t pid;
265         int i, last_i, n;
266         struct save_hist *new_hist;
267
268         get_jiffy_counts();
269         total_pcpu = 0;
270         /* total_vsz = 0; */
271         new_hist = xmalloc(sizeof(new_hist[0]) * ntop);
272         /*
273          * Make a pass through the data to get stats.
274          */
275         /* hist_iterations = 0; */
276         i = 0;
277         for (n = 0; n < ntop; n++) {
278                 cur = top + n;
279
280                 /*
281                  * Calculate time in cur process.  Time is sum of user time
282                  * and system time
283                  */
284                 pid = cur->pid;
285                 new_hist[n].ticks = cur->ticks;
286                 new_hist[n].pid = pid;
287
288                 /* find matching entry from previous pass */
289                 cur->pcpu = 0;
290                 /* do not start at index 0, continue at last used one
291                  * (brought hist_iterations from ~14000 down to 172) */
292                 last_i = i;
293                 if (prev_hist_count) do {
294                         if (prev_hist[i].pid == pid) {
295                                 cur->pcpu = cur->ticks - prev_hist[i].ticks;
296                                 total_pcpu += cur->pcpu;
297                                 break;
298                         }
299                         i = (i+1) % prev_hist_count;
300                         /* hist_iterations++; */
301                 } while (i != last_i);
302                 /* total_vsz += cur->vsz; */
303         }
304
305         /*
306          * Save cur frame's information.
307          */
308         free(prev_hist);
309         prev_hist = new_hist;
310         prev_hist_count = ntop;
311 }
312
313 #endif /* FEATURE_TOP_CPU_USAGE_PERCENTAGE */
314
315 #if ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS && ENABLE_FEATURE_TOP_DECIMALS
316 /* formats 7 char string (8 with terminating NUL) */
317 static char *fmt_100percent_8(char pbuf[8], unsigned value, unsigned total)
318 {
319         unsigned t;
320         if (value >= total) { /* 100% ? */
321                 strcpy(pbuf, "  100% ");
322                 return pbuf;
323         }
324         /* else generate " [N/space]N.N% " string */
325         value = 1000 * value / total;
326         t = value / 100;
327         value = value % 100;
328         pbuf[0] = ' ';
329         pbuf[1] = t ? t + '0' : ' ';
330         pbuf[2] = '0' + (value / 10);
331         pbuf[3] = '.';
332         pbuf[4] = '0' + (value % 10);
333         pbuf[5] = '%';
334         pbuf[6] = ' ';
335         pbuf[7] = '\0';
336         return pbuf;
337 }
338 #endif
339
340 #if ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS
341 static void display_cpus(int scr_width, char *scrbuf, int *lines_rem_p)
342 {
343         /*
344          * xxx% = (cur_jif.xxx - prev_jif.xxx) / (cur_jif.total - prev_jif.total) * 100%
345          */
346         unsigned total_diff;
347         jiffy_counts_t *p_jif, *p_prev_jif;
348         int i;
349 # if ENABLE_FEATURE_TOP_SMP_CPU
350         int n_cpu_lines;
351 # endif
352
353         /* using (unsigned) casts to make operations cheaper */
354 # define  CALC_TOTAL_DIFF do { \
355         total_diff = (unsigned)(p_jif->total - p_prev_jif->total); \
356         if (total_diff == 0) total_diff = 1; \
357 } while (0)
358
359 # if ENABLE_FEATURE_TOP_DECIMALS
360 #  define CALC_STAT(xxx) char xxx[8]
361 #  define SHOW_STAT(xxx) fmt_100percent_8(xxx, (unsigned)(p_jif->xxx - p_prev_jif->xxx), total_diff)
362 #  define FMT "%s"
363 # else
364 #  define CALC_STAT(xxx) unsigned xxx = 100 * (unsigned)(p_jif->xxx - p_prev_jif->xxx) / total_diff
365 #  define SHOW_STAT(xxx) xxx
366 #  define FMT "%4u%% "
367 # endif
368
369 # if !ENABLE_FEATURE_TOP_SMP_CPU
370         {
371                 i = 1;
372                 p_jif = &cur_jif;
373                 p_prev_jif = &prev_jif;
374 # else
375         /* Loop thru CPU(s) */
376         n_cpu_lines = smp_cpu_info ? num_cpus : 1;
377         if (n_cpu_lines > *lines_rem_p)
378                 n_cpu_lines = *lines_rem_p;
379
380         for (i = 0; i < n_cpu_lines; i++) {
381                 p_jif = &cpu_jif[i];
382                 p_prev_jif = &cpu_prev_jif[i];
383 # endif
384                 CALC_TOTAL_DIFF;
385
386                 { /* Need a block: CALC_STAT are declarations */
387                         CALC_STAT(usr);
388                         CALC_STAT(sys);
389                         CALC_STAT(nic);
390                         CALC_STAT(idle);
391                         CALC_STAT(iowait);
392                         CALC_STAT(irq);
393                         CALC_STAT(softirq);
394                         /*CALC_STAT(steal);*/
395
396                         snprintf(scrbuf, scr_width,
397                                 /* Barely fits in 79 chars when in "decimals" mode. */
398 # if ENABLE_FEATURE_TOP_SMP_CPU
399                                 "CPU%s:"FMT"usr"FMT"sys"FMT"nic"FMT"idle"FMT"io"FMT"irq"FMT"sirq",
400                                 (smp_cpu_info ? utoa(i) : ""),
401 # else
402                                 "CPU:"FMT"usr"FMT"sys"FMT"nic"FMT"idle"FMT"io"FMT"irq"FMT"sirq",
403 # endif
404                                 SHOW_STAT(usr), SHOW_STAT(sys), SHOW_STAT(nic), SHOW_STAT(idle),
405                                 SHOW_STAT(iowait), SHOW_STAT(irq), SHOW_STAT(softirq)
406                                 /*, SHOW_STAT(steal) - what is this 'steal' thing? */
407                                 /* I doubt anyone wants to know it */
408                         );
409                         puts(scrbuf);
410                 }
411         }
412 # undef SHOW_STAT
413 # undef CALC_STAT
414 # undef FMT
415         *lines_rem_p -= i;
416 }
417 #else  /* !ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS */
418 # define display_cpus(scr_width, scrbuf, lines_rem) ((void)0)
419 #endif
420
421 static unsigned long display_header(int scr_width, int *lines_rem_p)
422 {
423         FILE *fp;
424         char buf[80];
425         char scrbuf[80];
426         unsigned long total, used, mfree, shared, buffers, cached;
427
428         /* read memory info */
429         fp = xfopen_for_read("meminfo");
430
431         /*
432          * Old kernels (such as 2.4.x) had a nice summary of memory info that
433          * we could parse, however this is gone entirely in 2.6. Try parsing
434          * the old way first, and if that fails, parse each field manually.
435          *
436          * First, we read in the first line. Old kernels will have bogus
437          * strings we don't care about, whereas new kernels will start right
438          * out with MemTotal:
439          *                              -- PFM.
440          */
441         if (fscanf(fp, "MemTotal: %lu %s\n", &total, buf) != 2) {
442                 fgets(buf, sizeof(buf), fp);    /* skip first line */
443
444                 fscanf(fp, "Mem: %lu %lu %lu %lu %lu %lu",
445                         &total, &used, &mfree, &shared, &buffers, &cached);
446                 /* convert to kilobytes */
447                 used /= 1024;
448                 mfree /= 1024;
449                 shared /= 1024;
450                 buffers /= 1024;
451                 cached /= 1024;
452                 total /= 1024;
453         } else {
454                 /*
455                  * Revert to manual parsing, which incidentally already has the
456                  * sizes in kilobytes. This should be safe for both 2.4 and
457                  * 2.6.
458                  */
459                 fscanf(fp, "MemFree: %lu %s\n", &mfree, buf);
460
461                 /*
462                  * MemShared: is no longer present in 2.6. Report this as 0,
463                  * to maintain consistent behavior with normal procps.
464                  */
465                 if (fscanf(fp, "MemShared: %lu %s\n", &shared, buf) != 2)
466                         shared = 0;
467
468                 fscanf(fp, "Buffers: %lu %s\n", &buffers, buf);
469                 fscanf(fp, "Cached: %lu %s\n", &cached, buf);
470
471                 used = total - mfree;
472         }
473         fclose(fp);
474
475         /* output memory info */
476         if (scr_width > (int)sizeof(scrbuf))
477                 scr_width = sizeof(scrbuf);
478         snprintf(scrbuf, scr_width,
479                 "Mem: %luK used, %luK free, %luK shrd, %luK buff, %luK cached",
480                 used, mfree, shared, buffers, cached);
481         /* clear screen & go to top */
482         printf(OPT_BATCH_MODE ? "%s\n" : "\e[H\e[J%s\n", scrbuf);
483         (*lines_rem_p)--;
484
485         /* Display CPU time split as percentage of total time
486          * This displays either a cumulative line or one line per CPU
487          */
488         display_cpus(scr_width, scrbuf, lines_rem_p);
489
490         /* read load average as a string */
491         buf[0] = '\0';
492         open_read_close("loadavg", buf, sizeof(buf) - 1);
493         buf[sizeof(buf) - 1] = '\n';
494         *strchr(buf, '\n') = '\0';
495         snprintf(scrbuf, scr_width, "Load average: %s", buf);
496         puts(scrbuf);
497         (*lines_rem_p)--;
498
499         return total;
500 }
501
502 static NOINLINE void display_process_list(int lines_rem, int scr_width)
503 {
504         enum {
505                 BITS_PER_INT = sizeof(int) * 8
506         };
507
508         top_status_t *s;
509         char vsz_str_buf[8];
510         unsigned long total_memory = display_header(scr_width, &lines_rem); /* or use total_vsz? */
511         /* xxx_shift and xxx_scale variables allow us to replace
512          * expensive divides with multiply and shift */
513         unsigned pmem_shift, pmem_scale, pmem_half;
514 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
515         unsigned tmp_unsigned;
516         unsigned pcpu_shift, pcpu_scale, pcpu_half;
517         unsigned busy_jifs;
518 #endif
519
520         /* what info of the processes is shown */
521         printf(OPT_BATCH_MODE ? "%.*s" : "\e[7m%.*s\e[0m", scr_width,
522                 "  PID  PPID USER     STAT   VSZ %MEM"
523                 IF_FEATURE_TOP_SMP_PROCESS(" CPU")
524                 IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE(" %CPU")
525                 " COMMAND");
526         lines_rem--;
527
528 #if ENABLE_FEATURE_TOP_DECIMALS
529 # define UPSCALE 1000
530 # define CALC_STAT(name, val) div_t name = div((val), 10)
531 # define SHOW_STAT(name) name.quot, '0'+name.rem
532 # define FMT "%3u.%c"
533 #else
534 # define UPSCALE 100
535 # define CALC_STAT(name, val) unsigned name = (val)
536 # define SHOW_STAT(name) name
537 # define FMT "%4u%%"
538 #endif
539         /*
540          * MEM% = s->vsz/MemTotal
541          */
542         pmem_shift = BITS_PER_INT-11;
543         pmem_scale = UPSCALE*(1U<<(BITS_PER_INT-11)) / total_memory;
544         /* s->vsz is in kb. we want (s->vsz * pmem_scale) to never overflow */
545         while (pmem_scale >= 512) {
546                 pmem_scale /= 4;
547                 pmem_shift -= 2;
548         }
549         pmem_half = (1U << pmem_shift) / (ENABLE_FEATURE_TOP_DECIMALS? 20 : 2);
550 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
551         busy_jifs = cur_jif.busy - prev_jif.busy;
552         /* This happens if there were lots of short-lived processes
553          * between two top updates (e.g. compilation) */
554         if (total_pcpu < busy_jifs) total_pcpu = busy_jifs;
555
556         /*
557          * CPU% = s->pcpu/sum(s->pcpu) * busy_cpu_ticks/total_cpu_ticks
558          * (pcpu is delta of sys+user time between samples)
559          */
560         /* (cur_jif.xxx - prev_jif.xxx) and s->pcpu are
561          * in 0..~64000 range (HZ*update_interval).
562          * we assume that unsigned is at least 32-bit.
563          */
564         pcpu_shift = 6;
565         pcpu_scale = UPSCALE*64 * (uint16_t)busy_jifs;
566         if (pcpu_scale == 0)
567                 pcpu_scale = 1;
568         while (pcpu_scale < (1U << (BITS_PER_INT-2))) {
569                 pcpu_scale *= 4;
570                 pcpu_shift += 2;
571         }
572         tmp_unsigned = (uint16_t)(cur_jif.total - prev_jif.total) * total_pcpu;
573         if (tmp_unsigned != 0)
574                 pcpu_scale /= tmp_unsigned;
575         /* we want (s->pcpu * pcpu_scale) to never overflow */
576         while (pcpu_scale >= 1024) {
577                 pcpu_scale /= 4;
578                 pcpu_shift -= 2;
579         }
580         pcpu_half = (1U << pcpu_shift) / (ENABLE_FEATURE_TOP_DECIMALS? 20 : 2);
581         /* printf(" pmem_scale=%u pcpu_scale=%u ", pmem_scale, pcpu_scale); */
582 #endif
583
584         /* Ok, all preliminary data is ready, go through the list */
585         scr_width += 2; /* account for leading '\n' and trailing NUL */
586         if (lines_rem > ntop)
587                 lines_rem = ntop;
588         s = top;
589         while (--lines_rem >= 0) {
590                 unsigned col;
591                 CALC_STAT(pmem, (s->vsz*pmem_scale + pmem_half) >> pmem_shift);
592 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
593                 CALC_STAT(pcpu, (s->pcpu*pcpu_scale + pcpu_half) >> pcpu_shift);
594 #endif
595
596                 if (s->vsz >= 100000)
597                         sprintf(vsz_str_buf, "%6ldm", s->vsz/1024);
598                 else
599                         sprintf(vsz_str_buf, "%7ld", s->vsz);
600                 /* PID PPID USER STAT VSZ %MEM [%CPU] COMMAND */
601                 col = snprintf(line_buf, scr_width,
602                                 "\n" "%5u%6u %-8.8s %s%s" FMT
603                                 IF_FEATURE_TOP_SMP_PROCESS(" %3d")
604                                 IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE(FMT)
605                                 " ",
606                                 s->pid, s->ppid, get_cached_username(s->uid),
607                                 s->state, vsz_str_buf,
608                                 SHOW_STAT(pmem)
609                                 IF_FEATURE_TOP_SMP_PROCESS(, s->last_seen_on_cpu)
610                                 IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE(, SHOW_STAT(pcpu))
611                 );
612                 if ((int)(col + 1) < scr_width)
613                         read_cmdline(line_buf + col, scr_width - col, s->pid, s->comm);
614                 fputs(line_buf, stdout);
615                 /* printf(" %d/%d %lld/%lld", s->pcpu, total_pcpu,
616                         cur_jif.busy - prev_jif.busy, cur_jif.total - prev_jif.total); */
617                 s++;
618         }
619         /* printf(" %d", hist_iterations); */
620         bb_putchar(OPT_BATCH_MODE ? '\n' : '\r');
621         fflush_all();
622 }
623 #undef UPSCALE
624 #undef SHOW_STAT
625 #undef CALC_STAT
626 #undef FMT
627
628 static void clearmems(void)
629 {
630         clear_username_cache();
631         free(top);
632         top = NULL;
633         ntop = 0;
634 }
635
636 #if ENABLE_FEATURE_USE_TERMIOS
637
638 static void reset_term(void)
639 {
640         tcsetattr_stdin_TCSANOW(&initial_settings);
641         if (ENABLE_FEATURE_CLEAN_UP) {
642                 clearmems();
643 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
644                 free(prev_hist);
645 # endif
646         }
647 }
648
649 static void sig_catcher(int sig UNUSED_PARAM)
650 {
651         reset_term();
652         exit(EXIT_FAILURE);
653 }
654 #endif /* FEATURE_USE_TERMIOS */
655
656 /*
657  * TOPMEM support
658  */
659
660 typedef unsigned long mem_t;
661
662 typedef struct topmem_status_t {
663         unsigned pid;
664         char comm[COMM_LEN];
665         /* vsz doesn't count /dev/xxx mappings except /dev/zero */
666         mem_t vsz     ;
667         mem_t vszrw   ;
668         mem_t rss     ;
669         mem_t rss_sh  ;
670         mem_t dirty   ;
671         mem_t dirty_sh;
672         mem_t stack   ;
673 } topmem_status_t;
674
675 enum { NUM_SORT_FIELD = 7 };
676
677 #define topmem ((topmem_status_t*)top)
678
679 #if ENABLE_FEATURE_TOPMEM
680
681 static int topmem_sort(char *a, char *b)
682 {
683         int n;
684         mem_t l, r;
685
686         n = offsetof(topmem_status_t, vsz) + (sort_field * sizeof(mem_t));
687         l = *(mem_t*)(a + n);
688         r = *(mem_t*)(b + n);
689 //      if (l == r) {
690 //              l = a->mapped_rw;
691 //              r = b->mapped_rw;
692 //      }
693         /* We want to avoid unsigned->signed and truncation errors */
694         /* l>r: -1, l=r: 0, l<r: 1 */
695         n = (l > r) ? -1 : (l != r);
696         return inverted ? -n : n;
697 }
698
699 /* Cut "NNNN " out of "    NNNN kb" */
700 static char *grab_number(char *str, const char *match, unsigned sz)
701 {
702         if (strncmp(str, match, sz) == 0) {
703                 str = skip_whitespace(str + sz);
704                 (skip_non_whitespace(str))[1] = '\0';
705                 return xstrdup(str);
706         }
707         return NULL;
708 }
709
710 /* display header info (meminfo / loadavg) */
711 static void display_topmem_header(int scr_width, int *lines_rem_p)
712 {
713         char linebuf[128];
714         unsigned i;
715         FILE *fp;
716         union {
717                 struct {
718                         /*  1 */ char *total;
719                         /*  2 */ char *mfree;
720                         /*  3 */ char *buf;
721                         /*  4 */ char *cache;
722                         /*  5 */ char *swaptotal;
723                         /*  6 */ char *swapfree;
724                         /*  7 */ char *dirty;
725                         /*  8 */ char *mwrite;
726                         /*  9 */ char *anon;
727                         /* 10 */ char *map;
728                         /* 11 */ char *slab;
729                 } u;
730                 char *str[11];
731         } Z;
732 #define total     Z.u.total
733 #define mfree     Z.u.mfree
734 #define buf       Z.u.buf
735 #define cache     Z.u.cache
736 #define swaptotal Z.u.swaptotal
737 #define swapfree  Z.u.swapfree
738 #define dirty     Z.u.dirty
739 #define mwrite    Z.u.mwrite
740 #define anon      Z.u.anon
741 #define map       Z.u.map
742 #define slab      Z.u.slab
743 #define str       Z.str
744
745         memset(&Z, 0, sizeof(Z));
746
747         /* read memory info */
748         fp = xfopen_for_read("meminfo");
749         while (fgets(linebuf, sizeof(linebuf), fp)) {
750                 char *p;
751
752 #define SCAN(match, name) \
753                 p = grab_number(linebuf, match, sizeof(match)-1); \
754                 if (p) { name = p; continue; }
755
756                 SCAN("MemTotal:", total);
757                 SCAN("MemFree:", mfree);
758                 SCAN("Buffers:", buf);
759                 SCAN("Cached:", cache);
760                 SCAN("SwapTotal:", swaptotal);
761                 SCAN("SwapFree:", swapfree);
762                 SCAN("Dirty:", dirty);
763                 SCAN("Writeback:", mwrite);
764                 SCAN("AnonPages:", anon);
765                 SCAN("Mapped:", map);
766                 SCAN("Slab:", slab);
767 #undef SCAN
768         }
769         fclose(fp);
770
771 #define S(s) (s ? s : "0 ")
772         snprintf(linebuf, sizeof(linebuf),
773                 "Mem %stotal %sanon %smap %sfree",
774                 S(total), S(anon), S(map), S(mfree));
775         printf(OPT_BATCH_MODE ? "%.*s\n" : "\e[H\e[J%.*s\n", scr_width, linebuf);
776
777         snprintf(linebuf, sizeof(linebuf),
778                 " %sslab %sbuf %scache %sdirty %swrite",
779                 S(slab), S(buf), S(cache), S(dirty), S(mwrite));
780         printf("%.*s\n", scr_width, linebuf);
781
782         snprintf(linebuf, sizeof(linebuf),
783                 "Swap %stotal %sfree", // TODO: % used?
784                 S(swaptotal), S(swapfree));
785         printf("%.*s\n", scr_width, linebuf);
786
787         (*lines_rem_p) -= 3;
788 #undef S
789
790         for (i = 0; i < ARRAY_SIZE(str); i++)
791                 free(str[i]);
792 #undef total
793 #undef free
794 #undef buf
795 #undef cache
796 #undef swaptotal
797 #undef swapfree
798 #undef dirty
799 #undef write
800 #undef anon
801 #undef map
802 #undef slab
803 #undef str
804 }
805
806 static void ulltoa6_and_space(unsigned long long ul, char buf[6])
807 {
808         /* see http://en.wikipedia.org/wiki/Tera */
809         smart_ulltoa5(ul, buf, " mgtpezy");
810         buf[5] = ' ';
811 }
812
813 static NOINLINE void display_topmem_process_list(int lines_rem, int scr_width)
814 {
815 #define HDR_STR "  PID   VSZ VSZRW   RSS (SHR) DIRTY (SHR) STACK"
816 #define MIN_WIDTH sizeof(HDR_STR)
817         const topmem_status_t *s = topmem;
818
819         display_topmem_header(scr_width, &lines_rem);
820         strcpy(line_buf, HDR_STR " COMMAND");
821         line_buf[5 + sort_field * 6] = '*';
822         printf(OPT_BATCH_MODE ? "%.*s" : "\e[7m%.*s\e[0m", scr_width, line_buf);
823         lines_rem--;
824
825         if (lines_rem > ntop)
826                 lines_rem = ntop;
827         while (--lines_rem >= 0) {
828                 /* PID VSZ VSZRW RSS (SHR) DIRTY (SHR) COMMAND */
829                 ulltoa6_and_space(s->pid     , &line_buf[0*6]);
830                 ulltoa6_and_space(s->vsz     , &line_buf[1*6]);
831                 ulltoa6_and_space(s->vszrw   , &line_buf[2*6]);
832                 ulltoa6_and_space(s->rss     , &line_buf[3*6]);
833                 ulltoa6_and_space(s->rss_sh  , &line_buf[4*6]);
834                 ulltoa6_and_space(s->dirty   , &line_buf[5*6]);
835                 ulltoa6_and_space(s->dirty_sh, &line_buf[6*6]);
836                 ulltoa6_and_space(s->stack   , &line_buf[7*6]);
837                 line_buf[8*6] = '\0';
838                 if (scr_width > (int)MIN_WIDTH) {
839                         read_cmdline(&line_buf[8*6], scr_width - MIN_WIDTH, s->pid, s->comm);
840                 }
841                 printf("\n""%.*s", scr_width, line_buf);
842                 s++;
843         }
844         bb_putchar(OPT_BATCH_MODE ? '\n' : '\r');
845         fflush_all();
846 #undef HDR_STR
847 #undef MIN_WIDTH
848 }
849
850 #else
851 void display_topmem_process_list(int lines_rem, int scr_width);
852 int topmem_sort(char *a, char *b);
853 #endif /* TOPMEM */
854
855 /*
856  * end TOPMEM support
857  */
858
859 enum {
860         TOP_MASK = 0
861                 | PSSCAN_PID
862                 | PSSCAN_PPID
863                 | PSSCAN_VSZ
864                 | PSSCAN_STIME
865                 | PSSCAN_UTIME
866                 | PSSCAN_STATE
867                 | PSSCAN_COMM
868                 | PSSCAN_CPU
869                 | PSSCAN_UIDGID,
870         TOPMEM_MASK = 0
871                 | PSSCAN_PID
872                 | PSSCAN_SMAPS
873                 | PSSCAN_COMM,
874 };
875
876 int top_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
877 int top_main(int argc UNUSED_PARAM, char **argv)
878 {
879         int iterations;
880         unsigned lines, col;
881         int lines_rem;
882         unsigned interval;
883         char *str_interval, *str_iterations;
884         unsigned scan_mask = TOP_MASK;
885 #if ENABLE_FEATURE_USE_TERMIOS
886         struct termios new_settings;
887         struct pollfd pfd[1];
888         unsigned char c;
889
890         pfd[0].fd = 0;
891         pfd[0].events = POLLIN;
892 #endif
893
894         INIT_G();
895
896         interval = 5; /* default update interval is 5 seconds */
897         iterations = 0; /* infinite */
898 #if ENABLE_FEATURE_TOP_SMP_CPU
899         /*num_cpus = 0;*/
900         /*smp_cpu_info = 0;*/  /* to start with show aggregate */
901         cpu_jif = &cur_jif;
902         cpu_prev_jif = &prev_jif;
903 #endif
904
905         /* all args are options; -n NUM */
906         opt_complementary = "-"; /* options can be specified w/o dash */
907         col = getopt32(argv, "d:n:b"IF_FEATURE_TOPMEM("m"), &str_interval, &str_iterations);
908 #if ENABLE_FEATURE_TOPMEM
909         if (col & OPT_m) /* -m (busybox specific) */
910                 scan_mask = TOPMEM_MASK;
911 #endif
912         if (col & OPT_d) {
913                 /* work around for "-d 1" -> "-d -1" done by getopt32
914                  * (opt_complementary == "-" does this) */
915                 if (str_interval[0] == '-')
916                         str_interval++;
917                 /* Need to limit it to not overflow poll timeout */
918                 interval = xatou16(str_interval);
919         }
920         if (col & OPT_n) {
921                 if (str_iterations[0] == '-')
922                         str_iterations++;
923                 iterations = xatou(str_iterations);
924         }
925
926         /* change to /proc */
927         xchdir("/proc");
928 #if ENABLE_FEATURE_USE_TERMIOS
929         tcgetattr(0, (void *) &initial_settings);
930         memcpy(&new_settings, &initial_settings, sizeof(new_settings));
931         /* unbuffered input, turn off echo */
932         new_settings.c_lflag &= ~(ISIG | ICANON | ECHO | ECHONL);
933
934         bb_signals(BB_FATAL_SIGS, sig_catcher);
935         tcsetattr_stdin_TCSANOW(&new_settings);
936 #endif
937
938 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
939         sort_function[0] = pcpu_sort;
940         sort_function[1] = mem_sort;
941         sort_function[2] = time_sort;
942 #else
943         sort_function[0] = mem_sort;
944 #endif
945
946         while (1) {
947                 procps_status_t *p = NULL;
948
949                 lines = 24; /* default */
950                 col = 79;
951 #if ENABLE_FEATURE_USE_TERMIOS
952                 /* We output to stdout, we need size of stdout (not stdin)! */
953                 get_terminal_width_height(STDOUT_FILENO, &col, &lines);
954                 if (lines < 5 || col < 10) {
955                         sleep(interval);
956                         continue;
957                 }
958 #endif
959                 if (col > LINE_BUF_SIZE-2) /* +2 bytes for '\n', NUL, */
960                         col = LINE_BUF_SIZE-2;
961
962                 /* read process IDs & status for all the processes */
963                 while ((p = procps_scan(p, scan_mask)) != NULL) {
964                         int n;
965 #if ENABLE_FEATURE_TOPMEM
966                         if (scan_mask != TOPMEM_MASK)
967 #endif
968                         {
969                                 n = ntop;
970                                 top = xrealloc_vector(top, 6, ntop++);
971                                 top[n].pid = p->pid;
972                                 top[n].ppid = p->ppid;
973                                 top[n].vsz = p->vsz;
974 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
975                                 top[n].ticks = p->stime + p->utime;
976 #endif
977                                 top[n].uid = p->uid;
978                                 strcpy(top[n].state, p->state);
979                                 strcpy(top[n].comm, p->comm);
980 #if ENABLE_FEATURE_TOP_SMP_PROCESS
981                                 top[n].last_seen_on_cpu = p->last_seen_on_cpu;
982 #endif
983                         }
984 #if ENABLE_FEATURE_TOPMEM
985                         else { /* TOPMEM */
986                                 if (!(p->mapped_ro | p->mapped_rw))
987                                         continue; /* kernel threads are ignored */
988                                 n = ntop;
989                                 /* No bug here - top and topmem are the same */
990                                 top = xrealloc_vector(topmem, 6, ntop++);
991                                 strcpy(topmem[n].comm, p->comm);
992                                 topmem[n].pid      = p->pid;
993                                 topmem[n].vsz      = p->mapped_rw + p->mapped_ro;
994                                 topmem[n].vszrw    = p->mapped_rw;
995                                 topmem[n].rss_sh   = p->shared_clean + p->shared_dirty;
996                                 topmem[n].rss      = p->private_clean + p->private_dirty + topmem[n].rss_sh;
997                                 topmem[n].dirty    = p->private_dirty + p->shared_dirty;
998                                 topmem[n].dirty_sh = p->shared_dirty;
999                                 topmem[n].stack    = p->stack;
1000                         }
1001 #endif
1002                 } /* end of "while we read /proc" */
1003                 if (ntop == 0) {
1004                         bb_error_msg("no process info in /proc");
1005                         break;
1006                 }
1007
1008                 if (scan_mask != TOPMEM_MASK) {
1009 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
1010                         if (!prev_hist_count) {
1011                                 do_stats();
1012                                 usleep(100000);
1013                                 clearmems();
1014                                 continue;
1015                         }
1016                         do_stats();
1017                         /* TODO: we don't need to sort all 10000 processes, we need to find top 24! */
1018                         qsort(top, ntop, sizeof(top_status_t), (void*)mult_lvl_cmp);
1019 #else
1020                         qsort(top, ntop, sizeof(top_status_t), (void*)(sort_function[0]));
1021 #endif
1022                 }
1023 #if ENABLE_FEATURE_TOPMEM
1024                 else { /* TOPMEM */
1025                         qsort(topmem, ntop, sizeof(topmem_status_t), (void*)topmem_sort);
1026                 }
1027 #endif
1028                 lines_rem = lines;
1029                 if (OPT_BATCH_MODE) {
1030                         lines_rem = INT_MAX;
1031                 }
1032                 if (scan_mask != TOPMEM_MASK)
1033                         display_process_list(lines_rem, col);
1034 #if ENABLE_FEATURE_TOPMEM
1035                 else
1036                         display_topmem_process_list(lines_rem, col);
1037 #endif
1038                 clearmems();
1039                 if (iterations >= 0 && !--iterations)
1040                         break;
1041 #if !ENABLE_FEATURE_USE_TERMIOS
1042                 sleep(interval);
1043 #else
1044                 if (option_mask32 & (OPT_b|OPT_EOF))
1045                          /* batch mode, or EOF on stdin ("top </dev/null") */
1046                         sleep(interval);
1047                 else if (safe_poll(pfd, 1, interval * 1000) > 0) {
1048                         if (safe_read(STDIN_FILENO, &c, 1) != 1) { /* error/EOF? */
1049                                 option_mask32 |= OPT_EOF;
1050                                 continue;
1051                         }
1052                         if (c == initial_settings.c_cc[VINTR])
1053                                 break;
1054                         c |= 0x20; /* lowercase */
1055                         if (c == 'q')
1056                                 break;
1057                         if (c == 'n') {
1058                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1059                                 sort_function[0] = pid_sort;
1060                         }
1061                         if (c == 'm') {
1062                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1063                                 sort_function[0] = mem_sort;
1064 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
1065                                 sort_function[1] = pcpu_sort;
1066                                 sort_function[2] = time_sort;
1067 # endif
1068                         }
1069 # if ENABLE_FEATURE_SHOW_THREADS
1070                         if (c == 'h'
1071                          IF_FEATURE_TOPMEM(&& scan_mask != TOPMEM_MASK)
1072                         ) {
1073                                 scan_mask ^= PSSCAN_TASKS;
1074                         }
1075 # endif
1076 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
1077                         if (c == 'p') {
1078                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1079                                 sort_function[0] = pcpu_sort;
1080                                 sort_function[1] = mem_sort;
1081                                 sort_function[2] = time_sort;
1082                         }
1083                         if (c == 't') {
1084                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1085                                 sort_function[0] = time_sort;
1086                                 sort_function[1] = mem_sort;
1087                                 sort_function[2] = pcpu_sort;
1088                         }
1089 #  if ENABLE_FEATURE_TOPMEM
1090                         if (c == 's') {
1091                                 scan_mask = TOPMEM_MASK;
1092                                 free(prev_hist);
1093                                 prev_hist = NULL;
1094                                 prev_hist_count = 0;
1095                                 sort_field = (sort_field + 1) % NUM_SORT_FIELD;
1096                         }
1097                         if (c == 'r')
1098                                 inverted ^= 1;
1099 #  endif
1100 #  if ENABLE_FEATURE_TOP_SMP_CPU
1101                         /* procps-2.0.18 uses 'C', 3.2.7 uses '1' */
1102                         if (c == 'c' || c == '1') {
1103                                 /* User wants to toggle per cpu <> aggregate */
1104                                 if (smp_cpu_info) {
1105                                         free(cpu_prev_jif);
1106                                         free(cpu_jif);
1107                                         cpu_jif = &cur_jif;
1108                                         cpu_prev_jif = &prev_jif;
1109                                 } else {
1110                                         /* Prepare for xrealloc() */
1111                                         cpu_jif = cpu_prev_jif = NULL;
1112                                 }
1113                                 num_cpus = 0;
1114                                 smp_cpu_info = !smp_cpu_info;
1115                                 get_jiffy_counts();
1116                         }
1117 #  endif
1118 # endif
1119                 }
1120 #endif /* FEATURE_USE_TERMIOS */
1121         } /* end of "while (1)" */
1122
1123         bb_putchar('\n');
1124 #if ENABLE_FEATURE_USE_TERMIOS
1125         reset_term();
1126 #endif
1127         return EXIT_SUCCESS;
1128 }