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 };
 104
 105 enum { LINE_BUF_SIZE = COMMON_BUFSIZE - offsetof(struct globals, line_buf) };
 106
 107 #define G (*(struct globals*)&bb_common_bufsiz1)
 108 #define INIT_G() do { \
 109         struct G_sizecheck { \
 110                 char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
 111         }; \
 112 } while (0)
 113 #define top              (G.top               )
 114 #define ntop             (G.ntop              )
 115 #define sort_field       (G.sort_field        )
 116 #define inverted         (G.inverted          )
 117 #define smp_cpu_info     (G.smp_cpu_info      )
 118 #define initial_settings (G.initial_settings  )
 119 #define sort_function    (G.sort_function     )
 120 #define prev_hist        (G.prev_hist         )
 121 #define prev_hist_count  (G.prev_hist_count   )
 122 #define cur_jif          (G.cur_jif           )
 123 #define prev_jif         (G.prev_jif          )
 124 #define cpu_jif          (G.cpu_jif           )
 125 #define cpu_prev_jif     (G.cpu_prev_jif      )
 126 #define num_cpus         (G.num_cpus          )
 127 #define total_pcpu       (G.total_pcpu        )
 128 #define line_buf         (G.line_buf          )
 129
 130 enum {
 131         OPT_d = (1 << 0),
 132         OPT_n = (1 << 1),
 133         OPT_b = (1 << 2),
 134         OPT_m = (1 << 3),
 135         OPT_EOF = (1 << 4), /* pseudo: "we saw EOF in stdin" */
 136 };
 137 #define OPT_BATCH_MODE (option_mask32 & OPT_b)
 138
 139
 140 #if ENABLE_FEATURE_USE_TERMIOS
 141 static int pid_sort(top_status_t *P, top_status_t *Q)
 142 {
 143         /* Buggy wrt pids with high bit set */
 144         /* (linux pids are in [1..2^15-1]) */
 145         return (Q->pid - P->pid);
 146 }
 147 #endif
 148
 149 static int mem_sort(top_status_t *P, top_status_t *Q)
 150 {
 151         /* We want to avoid unsigned->signed and truncation errors */
 152         if (Q->vsz < P->vsz) return -1;
 153         return Q->vsz != P->vsz; /* 0 if ==, 1 if > */
 154 }
 155
 156
 157 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 158
 159 static int pcpu_sort(top_status_t *P, top_status_t *Q)
 160 {
 161         /* Buggy wrt ticks with high bit set */
 162         /* Affects only processes for which ticks overflow */
 163         return (int)Q->pcpu - (int)P->pcpu;
 164 }
 165
 166 static int time_sort(top_status_t *P, top_status_t *Q)
 167 {
 168         /* We want to avoid unsigned->signed and truncation errors */
 169         if (Q->ticks < P->ticks) return -1;
 170         return Q->ticks != P->ticks; /* 0 if ==, 1 if > */
 171 }
 172
 173 static int mult_lvl_cmp(void* a, void* b)
 174 {
 175         int i, cmp_val;
 176
 177         for (i = 0; i < SORT_DEPTH; i++) {
 178                 cmp_val = (*sort_function[i])(a, b);
 179                 if (cmp_val != 0)
 180                         return cmp_val;
 181         }
 182         return 0;
 183 }
 184
 185 static NOINLINE int read_cpu_jiffy(FILE *fp, jiffy_counts_t *p_jif)
 186 {
 187 #if !ENABLE_FEATURE_TOP_SMP_CPU
 188         static const char fmt[] = "cpu %llu %llu %llu %llu %llu %llu %llu %llu";
 189 #else
 190         static const char fmt[] = "cp%*s %llu %llu %llu %llu %llu %llu %llu %llu";
 191 #endif
 192         int ret;
 193
 194         if (!fgets(line_buf, LINE_BUF_SIZE, fp) || line_buf[0] != 'c' /* not "cpu" */)
 195                 return 0;
 196         ret = sscanf(line_buf, fmt,
 197                         &p_jif->usr, &p_jif->nic, &p_jif->sys, &p_jif->idle,
 198                         &p_jif->iowait, &p_jif->irq, &p_jif->softirq,
 199                         &p_jif->steal);
 200         if (ret >= 4) {
 201                 p_jif->total = p_jif->usr + p_jif->nic + p_jif->sys + p_jif->idle
 202                         + p_jif->iowait + p_jif->irq + p_jif->softirq + p_jif->steal;
 203                 /* procps 2.x does not count iowait as busy time */
 204                 p_jif->busy = p_jif->total - p_jif->idle - p_jif->iowait;
 205         }
 206
 207         return ret;
 208 }
 209
 210 static void get_jiffy_counts(void)
 211 {
 212         FILE* fp = xfopen_for_read("stat");
 213
 214         /* We need to parse cumulative counts even if SMP CPU display is on,
 215          * they are used to calculate per process CPU% */
 216         prev_jif = cur_jif;
 217         if (read_cpu_jiffy(fp, &cur_jif) < 4)
 218                 bb_error_msg_and_die("can't read /proc/stat");
 219
 220 #if !ENABLE_FEATURE_TOP_SMP_CPU
 221         fclose(fp);
 222         return;
 223 #else
 224         if (!smp_cpu_info) {
 225                 fclose(fp);
 226                 return;
 227         }
 228
 229         if (!num_cpus) {
 230                 /* First time here. How many CPUs?
 231                  * There will be at least 1 /proc/stat line with cpu%d
 232                  */
 233                 while (1) {
 234                         cpu_jif = xrealloc_vector(cpu_jif, 1, num_cpus);
 235                         if (read_cpu_jiffy(fp, &cpu_jif[num_cpus]) <= 4)
 236                                 break;
 237                         num_cpus++;
 238                 }
 239                 if (num_cpus == 0) /* /proc/stat with only "cpu ..." line?! */
 240                         smp_cpu_info = 0;
 241
 242                 cpu_prev_jif = xzalloc(sizeof(cpu_prev_jif[0]) * num_cpus);
 243
 244                 /* Otherwise the first per cpu display shows all 100% idles */
 245                 usleep(50000);
 246         } else { /* Non first time invocation */
 247                 jiffy_counts_t *tmp;
 248                 int i;
 249
 250                 /* First switch the sample pointers: no need to copy */
 251                 tmp = cpu_prev_jif;
 252                 cpu_prev_jif = cpu_jif;
 253                 cpu_jif = tmp;
 254
 255                 /* Get the new samples */
 256                 for (i = 0; i < num_cpus; i++)
 257                         read_cpu_jiffy(fp, &cpu_jif[i]);
 258         }
 259 #endif
 260         fclose(fp);
 261 }
 262
 263 static void do_stats(void)
 264 {
 265         top_status_t *cur;
 266         pid_t pid;
 267         int i, last_i, n;
 268         struct save_hist *new_hist;
 269
 270         get_jiffy_counts();
 271         total_pcpu = 0;
 272         /* total_vsz = 0; */
 273         new_hist = xmalloc(sizeof(new_hist[0]) * ntop);
 274         /*
 275          * Make a pass through the data to get stats.
 276          */
 277         /* hist_iterations = 0; */
 278         i = 0;
 279         for (n = 0; n < ntop; n++) {
 280                 cur = top + n;
 281
 282                 /*
 283                  * Calculate time in cur process.  Time is sum of user time
 284                  * and system time
 285                  */
 286                 pid = cur->pid;
 287                 new_hist[n].ticks = cur->ticks;
 288                 new_hist[n].pid = pid;
 289
 290                 /* find matching entry from previous pass */
 291                 cur->pcpu = 0;
 292                 /* do not start at index 0, continue at last used one
 293                  * (brought hist_iterations from ~14000 down to 172) */
 294                 last_i = i;
 295                 if (prev_hist_count) do {
 296                         if (prev_hist[i].pid == pid) {
 297                                 cur->pcpu = cur->ticks - prev_hist[i].ticks;
 298                                 total_pcpu += cur->pcpu;
 299                                 break;
 300                         }
 301                         i = (i+1) % prev_hist_count;
 302                         /* hist_iterations++; */
 303                 } while (i != last_i);
 304                 /* total_vsz += cur->vsz; */
 305         }
 306
 307         /*
 308          * Save cur frame's information.
 309          */
 310         free(prev_hist);
 311         prev_hist = new_hist;
 312         prev_hist_count = ntop;
 313 }
 314
 315 #endif /* FEATURE_TOP_CPU_USAGE_PERCENTAGE */
 316
 317 #if ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS && ENABLE_FEATURE_TOP_DECIMALS
 318 /* formats 7 char string (8 with terminating NUL) */
 319 static char *fmt_100percent_8(char pbuf[8], unsigned value, unsigned total)
 320 {
 321         unsigned t;
 322         if (value >= total) { /* 100% ? */
 323                 strcpy(pbuf, "  100% ");
 324                 return pbuf;
 325         }
 326         /* else generate " [N/space]N.N% " string */
 327         value = 1000 * value / total;
 328         t = value / 100;
 329         value = value % 100;
 330         pbuf[0] = ' ';
 331         pbuf[1] = t ? t + '0' : ' ';
 332         pbuf[2] = '0' + (value / 10);
 333         pbuf[3] = '.';
 334         pbuf[4] = '0' + (value % 10);
 335         pbuf[5] = '%';
 336         pbuf[6] = ' ';
 337         pbuf[7] = '\0';
 338         return pbuf;
 339 }
 340 #endif
 341
 342 #if ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS
 343 static void display_cpus(int scr_width, char *scrbuf, int *lines_rem_p)
 344 {
 345         /*
 346          * xxx% = (cur_jif.xxx - prev_jif.xxx) / (cur_jif.total - prev_jif.total) * 100%
 347          */
 348         unsigned total_diff;
 349         jiffy_counts_t *p_jif, *p_prev_jif;
 350         int i;
 351
 352 # if ENABLE_FEATURE_TOP_SMP_CPU
 353         int n_cpu_lines;
 354 # endif
 355
 356         /* using (unsigned) casts to make operations cheaper */
 357 # define  CALC_TOT_DIFF  ((unsigned)(p_jif->total - p_prev_jif->total) ? : 1)
 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                 total_diff = CALC_TOT_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 pcpu_shift, pcpu_scale, pcpu_half;
 516         unsigned busy_jifs;
 517 #endif
 518
 519         /* what info of the processes is shown */
 520         printf(OPT_BATCH_MODE ? "%.*s" : "\e[7m%.*s\e[0m", scr_width,
 521                 "  PID  PPID USER     STAT   VSZ %MEM"
 522 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 523                 " CPU"
 524 #endif
 525 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 526                 " %CPU"
 527 #endif
 528                 " COMMAND");
 529         lines_rem--;
 530
 531 #if ENABLE_FEATURE_TOP_DECIMALS
 532 # define UPSCALE 1000
 533 # define CALC_STAT(name, val) div_t name = div((val), 10)
 534 # define SHOW_STAT(name) name.quot, '0'+name.rem
 535 # define FMT "%3u.%c"
 536 #else
 537 # define UPSCALE 100
 538 # define CALC_STAT(name, val) unsigned name = (val)
 539 # define SHOW_STAT(name) name
 540 # define FMT "%4u%%"
 541 #endif
 542         /*
 543          * MEM% = s->vsz/MemTotal
 544          */
 545         pmem_shift = BITS_PER_INT-11;
 546         pmem_scale = UPSCALE*(1U<<(BITS_PER_INT-11)) / total_memory;
 547         /* s->vsz is in kb. we want (s->vsz * pmem_scale) to never overflow */
 548         while (pmem_scale >= 512) {
 549                 pmem_scale /= 4;
 550                 pmem_shift -= 2;
 551         }
 552         pmem_half = (1U << pmem_shift) / (ENABLE_FEATURE_TOP_DECIMALS? 20 : 2);
 553 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 554         busy_jifs = cur_jif.busy - prev_jif.busy;
 555         /* This happens if there were lots of short-lived processes
 556          * between two top updates (e.g. compilation) */
 557         if (total_pcpu < busy_jifs) total_pcpu = busy_jifs;
 558
 559         /*
 560          * CPU% = s->pcpu/sum(s->pcpu) * busy_cpu_ticks/total_cpu_ticks
 561          * (pcpu is delta of sys+user time between samples)
 562          */
 563         /* (cur_jif.xxx - prev_jif.xxx) and s->pcpu are
 564          * in 0..~64000 range (HZ*update_interval).
 565          * we assume that unsigned is at least 32-bit.
 566          */
 567         pcpu_shift = 6;
 568         pcpu_scale = (UPSCALE*64 * (uint16_t)busy_jifs ? : 1);
 569         while (pcpu_scale < (1U << (BITS_PER_INT-2))) {
 570                 pcpu_scale *= 4;
 571                 pcpu_shift += 2;
 572         }
 573         pcpu_scale /= ( (uint16_t)(cur_jif.total - prev_jif.total) * total_pcpu ? : 1);
 574         /* we want (s->pcpu * pcpu_scale) to never overflow */
 575         while (pcpu_scale >= 1024) {
 576                 pcpu_scale /= 4;
 577                 pcpu_shift -= 2;
 578         }
 579         pcpu_half = (1U << pcpu_shift) / (ENABLE_FEATURE_TOP_DECIMALS? 20 : 2);
 580         /* printf(" pmem_scale=%u pcpu_scale=%u ", pmem_scale, pcpu_scale); */
 581 #endif
 582
 583         /* Ok, all preliminary data is ready, go through the list */
 584         scr_width += 2; /* account for leading '\n' and trailing NUL */
 585         if (lines_rem > ntop)
 586                 lines_rem = ntop;
 587         s = top;
 588         while (--lines_rem >= 0) {
 589                 unsigned col;
 590                 CALC_STAT(pmem, (s->vsz*pmem_scale + pmem_half) >> pmem_shift);
 591 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 592                 CALC_STAT(pcpu, (s->pcpu*pcpu_scale + pcpu_half) >> pcpu_shift);
 593 #endif
 594
 595                 if (s->vsz >= 100000)
 596                         sprintf(vsz_str_buf, "%6ldm", s->vsz/1024);
 597                 else
 598                         sprintf(vsz_str_buf, "%7ld", s->vsz);
 599                 /* PID PPID USER STAT VSZ %MEM [%CPU] COMMAND */
 600                 col = snprintf(line_buf, scr_width,
 601                                 "\n" "%5u%6u %-8.8s %s%s" FMT
 602 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 603                                 " %3d"
 604 #endif
 605 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 606                                 FMT
 607 #endif
 608                                 " ",
 609                                 s->pid, s->ppid, get_cached_username(s->uid),
 610                                 s->state, vsz_str_buf,
 611                                 SHOW_STAT(pmem)
 612 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 613                                 , s->last_seen_on_cpu
 614 #endif
 615 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 616                                 , SHOW_STAT(pcpu)
 617 #endif
 618                 );
 619                 if ((int)(col + 1) < scr_width)
 620                         read_cmdline(line_buf + col, scr_width - col - 1, s->pid, s->comm);
 621                 fputs(line_buf, stdout);
 622                 /* printf(" %d/%d %lld/%lld", s->pcpu, total_pcpu,
 623                         cur_jif.busy - prev_jif.busy, cur_jif.total - prev_jif.total); */
 624                 s++;
 625         }
 626         /* printf(" %d", hist_iterations); */
 627         bb_putchar(OPT_BATCH_MODE ? '\n' : '\r');
 628         fflush(stdout);
 629 }
 630 #undef UPSCALE
 631 #undef SHOW_STAT
 632 #undef CALC_STAT
 633 #undef FMT
 634
 635 static void clearmems(void)
 636 {
 637         clear_username_cache();
 638         free(top);
 639         top = NULL;
 640         ntop = 0;
 641 }
 642
 643 #if ENABLE_FEATURE_USE_TERMIOS
 644
 645 static void reset_term(void)
 646 {
 647         tcsetattr_stdin_TCSANOW(&initial_settings);
 648         if (ENABLE_FEATURE_CLEAN_UP) {
 649                 clearmems();
 650 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 651                 free(prev_hist);
 652 # endif
 653         }
 654 }
 655
 656 static void sig_catcher(int sig UNUSED_PARAM)
 657 {
 658         reset_term();
 659         exit(EXIT_FAILURE);
 660 }
 661 #endif /* FEATURE_USE_TERMIOS */
 662
 663 /*
 664  * TOPMEM support
 665  */
 666
 667 typedef unsigned long mem_t;
 668
 669 typedef struct topmem_status_t {
 670         unsigned pid;
 671         char comm[COMM_LEN];
 672         /* vsz doesn't count /dev/xxx mappings except /dev/zero */
 673         mem_t vsz     ;
 674         mem_t vszrw   ;
 675         mem_t rss     ;
 676         mem_t rss_sh  ;
 677         mem_t dirty   ;
 678         mem_t dirty_sh;
 679         mem_t stack   ;
 680 } topmem_status_t;
 681
 682 enum { NUM_SORT_FIELD = 7 };
 683
 684 #define topmem ((topmem_status_t*)top)
 685
 686 #if ENABLE_FEATURE_TOPMEM
 687
 688 static int topmem_sort(char *a, char *b)
 689 {
 690         int n;
 691         mem_t l, r;
 692
 693         n = offsetof(topmem_status_t, vsz) + (sort_field * sizeof(mem_t));
 694         l = *(mem_t*)(a + n);
 695         r = *(mem_t*)(b + n);
 696 //      if (l == r) {
 697 //              l = a->mapped_rw;
 698 //              r = b->mapped_rw;
 699 //      }
 700         /* We want to avoid unsigned->signed and truncation errors */
 701         /* l>r: -1, l=r: 0, l<r: 1 */
 702         n = (l > r) ? -1 : (l != r);
 703         return inverted ? -n : n;
 704 }
 705
 706 /* Cut "NNNN " out of "    NNNN kb" */
 707 static char *grab_number(char *str, const char *match, unsigned sz)
 708 {
 709         if (strncmp(str, match, sz) == 0) {
 710                 str = skip_whitespace(str + sz);
 711                 (skip_non_whitespace(str))[1] = '\0';
 712                 return xstrdup(str);
 713         }
 714         return NULL;
 715 }
 716
 717 /* display header info (meminfo / loadavg) */
 718 static void display_topmem_header(int scr_width, int *lines_rem_p)
 719 {
 720         char linebuf[128];
 721         unsigned i;
 722         FILE *fp;
 723         union {
 724                 struct {
 725                         /*  1 */ char *total;
 726                         /*  2 */ char *mfree;
 727                         /*  3 */ char *buf;
 728                         /*  4 */ char *cache;
 729                         /*  5 */ char *swaptotal;
 730                         /*  6 */ char *swapfree;
 731                         /*  7 */ char *dirty;
 732                         /*  8 */ char *mwrite;
 733                         /*  9 */ char *anon;
 734                         /* 10 */ char *map;
 735                         /* 11 */ char *slab;
 736                 } u;
 737                 char *str[11];
 738         } Z;
 739 #define total     Z.u.total
 740 #define mfree     Z.u.mfree
 741 #define buf       Z.u.buf
 742 #define cache     Z.u.cache
 743 #define swaptotal Z.u.swaptotal
 744 #define swapfree  Z.u.swapfree
 745 #define dirty     Z.u.dirty
 746 #define mwrite    Z.u.mwrite
 747 #define anon      Z.u.anon
 748 #define map       Z.u.map
 749 #define slab      Z.u.slab
 750 #define str       Z.str
 751
 752         memset(&Z, 0, sizeof(Z));
 753
 754         /* read memory info */
 755         fp = xfopen_for_read("meminfo");
 756         while (fgets(linebuf, sizeof(linebuf), fp)) {
 757                 char *p;
 758
 759 #define SCAN(match, name) \
 760                 p = grab_number(linebuf, match, sizeof(match)-1); \
 761                 if (p) { name = p; continue; }
 762
 763                 SCAN("MemTotal:", total);
 764                 SCAN("MemFree:", mfree);
 765                 SCAN("Buffers:", buf);
 766                 SCAN("Cached:", cache);
 767                 SCAN("SwapTotal:", swaptotal);
 768                 SCAN("SwapFree:", swapfree);
 769                 SCAN("Dirty:", dirty);
 770                 SCAN("Writeback:", mwrite);
 771                 SCAN("AnonPages:", anon);
 772                 SCAN("Mapped:", map);
 773                 SCAN("Slab:", slab);
 774 #undef SCAN
 775         }
 776         fclose(fp);
 777
 778 #define S(s) (s ? s : "0 ")
 779         snprintf(linebuf, sizeof(linebuf),
 780                 "Mem %stotal %sanon %smap %sfree",
 781                 S(total), S(anon), S(map), S(mfree));
 782         printf(OPT_BATCH_MODE ? "%.*s\n" : "\e[H\e[J%.*s\n", scr_width, linebuf);
 783
 784         snprintf(linebuf, sizeof(linebuf),
 785                 " %sslab %sbuf %scache %sdirty %swrite",
 786                 S(slab), S(buf), S(cache), S(dirty), S(mwrite));
 787         printf("%.*s\n", scr_width, linebuf);
 788
 789         snprintf(linebuf, sizeof(linebuf),
 790                 "Swap %stotal %sfree", // TODO: % used?
 791                 S(swaptotal), S(swapfree));
 792         printf("%.*s\n", scr_width, linebuf);
 793
 794         (*lines_rem_p) -= 3;
 795 #undef S
 796
 797         for (i = 0; i < ARRAY_SIZE(str); i++)
 798                 free(str[i]);
 799 #undef total
 800 #undef free
 801 #undef buf
 802 #undef cache
 803 #undef swaptotal
 804 #undef swapfree
 805 #undef dirty
 806 #undef write
 807 #undef anon
 808 #undef map
 809 #undef slab
 810 #undef str
 811 }
 812
 813 static void ulltoa6_and_space(unsigned long long ul, char buf[6])
 814 {
 815         /* see http://en.wikipedia.org/wiki/Tera */
 816         smart_ulltoa5(ul, buf, " mgtpezy");
 817         buf[5] = ' ';
 818 }
 819
 820 static NOINLINE void display_topmem_process_list(int lines_rem, int scr_width)
 821 {
 822 #define HDR_STR "  PID   VSZ VSZRW   RSS (SHR) DIRTY (SHR) STACK"
 823 #define MIN_WIDTH sizeof(HDR_STR)
 824         const topmem_status_t *s = topmem;
 825
 826         display_topmem_header(scr_width, &lines_rem);
 827         strcpy(line_buf, HDR_STR " COMMAND");
 828         line_buf[5 + sort_field * 6] = '*';
 829         printf(OPT_BATCH_MODE ? "%.*s" : "\e[7m%.*s\e[0m", scr_width, line_buf);
 830         lines_rem--;
 831
 832         if (lines_rem > ntop)
 833                 lines_rem = ntop;
 834         while (--lines_rem >= 0) {
 835                 /* PID VSZ VSZRW RSS (SHR) DIRTY (SHR) COMMAND */
 836                 ulltoa6_and_space(s->pid     , &line_buf[0*6]);
 837                 ulltoa6_and_space(s->vsz     , &line_buf[1*6]);
 838                 ulltoa6_and_space(s->vszrw   , &line_buf[2*6]);
 839                 ulltoa6_and_space(s->rss     , &line_buf[3*6]);
 840                 ulltoa6_and_space(s->rss_sh  , &line_buf[4*6]);
 841                 ulltoa6_and_space(s->dirty   , &line_buf[5*6]);
 842                 ulltoa6_and_space(s->dirty_sh, &line_buf[6*6]);
 843                 ulltoa6_and_space(s->stack   , &line_buf[7*6]);
 844                 line_buf[8*6] = '\0';
 845                 if (scr_width > (int)MIN_WIDTH) {
 846                         read_cmdline(&line_buf[8*6], scr_width - MIN_WIDTH, s->pid, s->comm);
 847                 }
 848                 printf("\n""%.*s", scr_width, line_buf);
 849                 s++;
 850         }
 851         bb_putchar(OPT_BATCH_MODE ? '\n' : '\r');
 852         fflush(stdout);
 853 #undef HDR_STR
 854 #undef MIN_WIDTH
 855 }
 856
 857 #else
 858 void display_topmem_process_list(int lines_rem, int scr_width);
 859 int topmem_sort(char *a, char *b);
 860 #endif /* TOPMEM */
 861
 862 /*
 863  * end TOPMEM support
 864  */
 865
 866 enum {
 867         TOP_MASK = 0
 868                 | PSSCAN_PID
 869                 | PSSCAN_PPID
 870                 | PSSCAN_VSZ
 871                 | PSSCAN_STIME
 872                 | PSSCAN_UTIME
 873                 | PSSCAN_STATE
 874                 | PSSCAN_COMM
 875                 | PSSCAN_CPU
 876                 | PSSCAN_UIDGID,
 877         TOPMEM_MASK = 0
 878                 | PSSCAN_PID
 879                 | PSSCAN_SMAPS
 880                 | PSSCAN_COMM,
 881 };
 882
 883 int top_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 884 int top_main(int argc UNUSED_PARAM, char **argv)
 885 {
 886         int iterations;
 887         unsigned lines, col;
 888         int lines_rem;
 889         unsigned interval;
 890         char *str_interval, *str_iterations;
 891         IF_NOT_FEATURE_TOPMEM(const) unsigned scan_mask = TOP_MASK;
 892 #if ENABLE_FEATURE_USE_TERMIOS
 893         struct termios new_settings;
 894         struct pollfd pfd[1];
 895         unsigned char c;
 896
 897         pfd[0].fd = 0;
 898         pfd[0].events = POLLIN;
 899 #endif
 900
 901         INIT_G();
 902
 903         interval = 5; /* default update interval is 5 seconds */
 904         iterations = 0; /* infinite */
 905 #if ENABLE_FEATURE_TOP_SMP_CPU
 906         /*num_cpus = 0;*/
 907         /*smp_cpu_info = 0;*/  /* to start with show aggregate */
 908         cpu_jif = &cur_jif;
 909         cpu_prev_jif = &prev_jif;
 910 #endif
 911
 912         /* all args are options; -n NUM */
 913         opt_complementary = "-"; /* options can be specified w/o dash */
 914         col = getopt32(argv, "d:n:b"IF_FEATURE_TOPMEM("m"), &str_interval, &str_iterations);
 915 #if ENABLE_FEATURE_TOPMEM
 916         if (col & OPT_m) /* -m (busybox specific) */
 917                 scan_mask = TOPMEM_MASK;
 918 #endif
 919         if (col & OPT_d) {
 920                 /* work around for "-d 1" -> "-d -1" done by getopt32
 921                  * (opt_complementary == "-" does this) */
 922                 if (str_interval[0] == '-')
 923                         str_interval++;
 924                 /* Need to limit it to not overflow poll timeout */
 925                 interval = xatou16(str_interval);
 926         }
 927         if (col & OPT_n) {
 928                 if (str_iterations[0] == '-')
 929                         str_iterations++;
 930                 iterations = xatou(str_iterations);
 931         }
 932
 933         /* change to /proc */
 934         xchdir("/proc");
 935 #if ENABLE_FEATURE_USE_TERMIOS
 936         tcgetattr(0, (void *) &initial_settings);
 937         memcpy(&new_settings, &initial_settings, sizeof(new_settings));
 938         /* unbuffered input, turn off echo */
 939         new_settings.c_lflag &= ~(ISIG | ICANON | ECHO | ECHONL);
 940
 941         bb_signals(BB_FATAL_SIGS, sig_catcher);
 942         tcsetattr_stdin_TCSANOW(&new_settings);
 943 #endif
 944
 945 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 946         sort_function[0] = pcpu_sort;
 947         sort_function[1] = mem_sort;
 948         sort_function[2] = time_sort;
 949 #else
 950         sort_function[0] = mem_sort;
 951 #endif
 952
 953         while (1) {
 954                 procps_status_t *p = NULL;
 955
 956                 lines = 24; /* default */
 957                 col = 79;
 958 #if ENABLE_FEATURE_USE_TERMIOS
 959                 /* We output to stdout, we need size of stdout (not stdin)! */
 960                 get_terminal_width_height(STDOUT_FILENO, &col, &lines);
 961                 if (lines < 5 || col < 10) {
 962                         sleep(interval);
 963                         continue;
 964                 }
 965 #endif
 966                 if (col > LINE_BUF_SIZE-2) /* +2 bytes for '\n', NUL, */
 967                         col = LINE_BUF_SIZE-2;
 968
 969                 /* read process IDs & status for all the processes */
 970                 while ((p = procps_scan(p, scan_mask)) != NULL) {
 971                         int n;
 972                         if (scan_mask == TOP_MASK) {
 973                                 n = ntop;
 974                                 top = xrealloc_vector(top, 6, ntop++);
 975                                 top[n].pid = p->pid;
 976                                 top[n].ppid = p->ppid;
 977                                 top[n].vsz = p->vsz;
 978 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
 979                                 top[n].ticks = p->stime + p->utime;
 980 #endif
 981                                 top[n].uid = p->uid;
 982                                 strcpy(top[n].state, p->state);
 983                                 strcpy(top[n].comm, p->comm);
 984 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 985                                 top[n].last_seen_on_cpu = p->last_seen_on_cpu;
 986 #endif
 987                         } else { /* TOPMEM */
 988 #if ENABLE_FEATURE_TOPMEM
 989                                 if (!(p->mapped_ro | p->mapped_rw))
 990                                         continue; /* kernel threads are ignored */
 991                                 n = ntop;
 992                                 /* No bug here - top and topmem are the same */
 993                                 top = xrealloc_vector(topmem, 6, ntop++);
 994                                 strcpy(topmem[n].comm, p->comm);
 995                                 topmem[n].pid      = p->pid;
 996                                 topmem[n].vsz      = p->mapped_rw + p->mapped_ro;
 997                                 topmem[n].vszrw    = p->mapped_rw;
 998                                 topmem[n].rss_sh   = p->shared_clean + p->shared_dirty;
 999                                 topmem[n].rss      = p->private_clean + p->private_dirty + topmem[n].rss_sh;
1000                                 topmem[n].dirty    = p->private_dirty + p->shared_dirty;
1001                                 topmem[n].dirty_sh = p->shared_dirty;
1002                                 topmem[n].stack    = p->stack;
1003 #endif
1004                         }
1005                 } /* end of "while we read /proc" */
1006                 if (ntop == 0) {
1007                         bb_error_msg("no process info in /proc");
1008                         break;
1009                 }
1010
1011                 if (scan_mask == TOP_MASK) {
1012 #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
1013                         if (!prev_hist_count) {
1014                                 do_stats();
1015                                 usleep(100000);
1016                                 clearmems();
1017                                 continue;
1018                         }
1019                         do_stats();
1020                         /* TODO: we don't need to sort all 10000 processes, we need to find top 24! */
1021                         qsort(top, ntop, sizeof(top_status_t), (void*)mult_lvl_cmp);
1022 #else
1023                         qsort(top, ntop, sizeof(top_status_t), (void*)(sort_function[0]));
1024 #endif
1025                 }
1026 #if ENABLE_FEATURE_TOPMEM
1027                 else { /* TOPMEM */
1028                         qsort(topmem, ntop, sizeof(topmem_status_t), (void*)topmem_sort);
1029                 }
1030 #endif
1031                 lines_rem = lines;
1032                 if (OPT_BATCH_MODE) {
1033                         lines_rem = INT_MAX;
1034                 }
1035                 if (scan_mask == TOP_MASK)
1036                         display_process_list(lines_rem, col);
1037 #if ENABLE_FEATURE_TOPMEM
1038                 else
1039                         display_topmem_process_list(lines_rem, col);
1040 #endif
1041                 clearmems();
1042                 if (iterations >= 0 && !--iterations)
1043                         break;
1044 #if !ENABLE_FEATURE_USE_TERMIOS
1045                 sleep(interval);
1046 #else
1047                 if (option_mask32 & (OPT_b|OPT_EOF))
1048                          /* batch mode, or EOF on stdin ("top </dev/null") */
1049                         sleep(interval);
1050                 else if (safe_poll(pfd, 1, interval * 1000) > 0) {
1051                         if (safe_read(STDIN_FILENO, &c, 1) != 1) { /* error/EOF? */
1052                                 option_mask32 |= OPT_EOF;
1053                                 continue;
1054                         }
1055                         if (c == initial_settings.c_cc[VINTR])
1056                                 break;
1057                         c |= 0x20; /* lowercase */
1058                         if (c == 'q')
1059                                 break;
1060                         if (c == 'n') {
1061                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1062                                 sort_function[0] = pid_sort;
1063                         }
1064                         if (c == 'm') {
1065                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1066                                 sort_function[0] = mem_sort;
1067 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
1068                                 sort_function[1] = pcpu_sort;
1069                                 sort_function[2] = time_sort;
1070 # endif
1071                         }
1072 # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
1073                         if (c == 'p') {
1074                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1075                                 sort_function[0] = pcpu_sort;
1076                                 sort_function[1] = mem_sort;
1077                                 sort_function[2] = time_sort;
1078                         }
1079                         if (c == 't') {
1080                                 IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
1081                                 sort_function[0] = time_sort;
1082                                 sort_function[1] = mem_sort;
1083                                 sort_function[2] = pcpu_sort;
1084                         }
1085 #  if ENABLE_FEATURE_TOPMEM
1086                         if (c == 's') {
1087                                 scan_mask = TOPMEM_MASK;
1088                                 free(prev_hist);
1089                                 prev_hist = NULL;
1090                                 prev_hist_count = 0;
1091                                 sort_field = (sort_field + 1) % NUM_SORT_FIELD;
1092                         }
1093                         if (c == 'r')
1094                                 inverted ^= 1;
1095 #  endif
1096 #  if ENABLE_FEATURE_TOP_SMP_CPU
1097                         /* procps-2.0.18 uses 'C', 3.2.7 uses '1' */
1098                         if (c == 'c' || c == '1') {
1099                                 /* User wants to toggle per cpu <> aggregate */
1100                                 if (smp_cpu_info) {
1101                                         free(cpu_prev_jif);
1102                                         free(cpu_jif);
1103                                         cpu_jif = &cur_jif;
1104                                         cpu_prev_jif = &prev_jif;
1105                                 } else {
1106                                         /* Prepare for xrealloc() */
1107                                         cpu_jif = cpu_prev_jif = NULL;
1108                                 }
1109                                 num_cpus = 0;
1110                                 smp_cpu_info = !smp_cpu_info;
1111                                 get_jiffy_counts();
1112                         }
1113 #  endif
1114 # endif
1115                 }
1116 #endif /* FEATURE_USE_TERMIOS */
1117         } /* end of "while (1)" */
1118
1119         bb_putchar('\n');
1120 #if ENABLE_FEATURE_USE_TERMIOS
1121         reset_term();
1122 #endif
1123         return EXIT_SUCCESS;
1124 }