text: /* vi: set sw=4 ts=4: */
  /*
   * A tiny 'top' utility.
   *
   * This is written specifically for the linux /proc/<PID>/stat(m)
   * files format.
   *
   * This reads the PIDs of all processes and their status and shows
   * the status of processes (first ones that fit to screen) at given
   * intervals.
   *
   * NOTES:
   * - At startup this changes to /proc, all the reads are then
   *   relative to that.
   *
   * (C) Eero Tamminen <oak at welho dot com>
   *
   * Rewritten by Vladimir Oleynik (C) 2002 <dzo@simtreas.ru>
   *
   * Sept 2008: Vineet Gupta <vineet.gupta@arc.com>
   * Added Support for reporting SMP Information
   * - CPU where process was last seen running
   *   (to see effect of sched_setaffinity() etc)
   * - CPU time split (idle/IO/wait etc) per CPU
   *
   * Copyright (c) 1992 Branko Lankester
   * Copyright (c) 1992 Roger Binns
   * Copyright (C) 1994-1996 Charles L. Blake.
   * Copyright (C) 1992-1998 Michael K. Johnson
   *
   * Licensed under GPLv2, see file LICENSE in this source tree.
   */
  /* How to snapshot /proc for debugging top problems:
   * for f in /proc/[0-9]*""/stat; do
   *         n=${f#/proc/}
   *         n=${n%/stat}_stat
   *         cp $f $n
   * done
   * cp /proc/stat /proc/meminfo /proc/loadavg .
   * top -bn1 >top.out
   *
   * ...and how to run top on it on another machine:
   * rm -rf proc; mkdir proc
   * for f in [0-9]*_stat; do
   *         p=${f%_stat}
   *         mkdir -p proc/$p
   *         cp $f proc/$p/stat
   * done
   * cp stat meminfo loadavg proc
   * chroot . ./top -bn1 >top1.out
   */
  //config:config TOP
  //config:	bool "top (17 kb)"
  //config:	default y
  //config:	help
  //config:	The top program provides a dynamic real-time view of a running
  //config:	system.
  //config:
  //config:config FEATURE_TOP_INTERACTIVE
  //config:	bool "Accept keyboard commands"
  //config:	default y
  //config:	depends on TOP
  //config:	help
  //config:	Without this, top will only refresh display every 5 seconds.
  //config:	No keyboard commands will work, only ^C to terminate.
  //config:
  //config:config FEATURE_TOP_CPU_USAGE_PERCENTAGE
  //config:	bool "Show CPU per-process usage percentage"
  //config:	default y
  //config:	depends on TOP
  //config:	help
  //config:	Make top display CPU usage for each process.
  //config:	This adds about 2k.
  //config:
  //config:config FEATURE_TOP_CPU_GLOBAL_PERCENTS
  //config:	bool "Show CPU global usage percentage"
  //config:	default y
  //config:	depends on FEATURE_TOP_CPU_USAGE_PERCENTAGE
  //config:	help
  //config:	Makes top display "CPU: NN% usr NN% sys..." line.
  //config:	This adds about 0.5k.
  //config:
  //config:config FEATURE_TOP_SMP_CPU
  //config:	bool "SMP CPU usage display ('c' key)"
  //config:	default y
  //config:	depends on FEATURE_TOP_CPU_GLOBAL_PERCENTS
  //config:	help
  //config:	Allow 'c' key to switch between individual/cumulative CPU stats
  //config:	This adds about 0.5k.
  //config:
  //config:config FEATURE_TOP_DECIMALS
  //config:	bool "Show 1/10th of a percent in CPU/mem statistics"
  //config:	default y
  //config:	depends on FEATURE_TOP_CPU_USAGE_PERCENTAGE
  //config:	help
  //config:	Show 1/10th of a percent in CPU/mem statistics.
  //config:	This adds about 0.3k.
  //config:
  //config:config FEATURE_TOP_SMP_PROCESS
  //config:	bool "Show CPU process runs on ('j' field)"
  //config:	default y
  //config:	depends on TOP
  //config:	help
  //config:	Show CPU where process was last found running on.
  //config:	This is the 'j' field.
  //config:
  //config:config FEATURE_TOPMEM
  //config:	bool "Topmem command ('s' key)"
  //config:	default y
  //config:	depends on TOP
  //config:	help
  //config:	Enable 's' in top (gives lots of memory info).
  
  //applet:IF_TOP(APPLET(top, BB_DIR_USR_BIN, BB_SUID_DROP))
  
  //kbuild:lib-$(CONFIG_TOP) += top.o
  
  #include "libbb.h"
  
  #define ESC "\033"
  
  typedef struct top_status_t {
  	unsigned long vsz;
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  	unsigned long ticks;
  	unsigned pcpu; /* delta of ticks */
  #endif
  	unsigned pid, ppid;
  	unsigned uid;
  	char state[4];
  	char comm[COMM_LEN];
  #if ENABLE_FEATURE_TOP_SMP_PROCESS
  	int last_seen_on_cpu;
  #endif
  } top_status_t;
  
  typedef struct jiffy_counts_t {
  	/* Linux 2.4.x has only first four */
  	unsigned long long usr, nic, sys, idle;
  	unsigned long long iowait, irq, softirq, steal;
  	unsigned long long total;
  	unsigned long long busy;
  } jiffy_counts_t;
  
  /* This structure stores some critical information from one frame to
     the next. Used for finding deltas. */
  typedef struct save_hist {
  	unsigned long ticks;
  	pid_t pid;
  } save_hist;
  
  typedef int (*cmp_funcp)(top_status_t *P, top_status_t *Q);
  
  
  enum { SORT_DEPTH = 3 };
  
  /* Screens wider than this are unlikely */
  enum { LINE_BUF_SIZE = 512 - 64 };
  
  struct globals {
  	top_status_t *top;
  	int ntop;
  	smallint inverted;
  #if ENABLE_FEATURE_TOPMEM
  	smallint sort_field;
  #endif
  #if ENABLE_FEATURE_TOP_SMP_CPU
  	smallint smp_cpu_info; /* one/many cpu info lines? */
  #endif
  	unsigned lines;  /* screen height */
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  	struct termios initial_settings;
  	int scroll_ofs;
  #define G_scroll_ofs G.scroll_ofs
  #else
  #define G_scroll_ofs 0
  #endif
  #if !ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  	cmp_funcp sort_function[1];
  #else
  	cmp_funcp sort_function[SORT_DEPTH];
  	struct save_hist *prev_hist;
  	int prev_hist_count;
  	jiffy_counts_t cur_jif, prev_jif;
  	/* int hist_iterations; */
  	unsigned total_pcpu;
  	/* unsigned long total_vsz; */
  #endif
  #if ENABLE_FEATURE_TOP_SMP_CPU
  	/* Per CPU samples: current and last */
  	jiffy_counts_t *cpu_jif, *cpu_prev_jif;
  	int num_cpus;
  #endif
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  	char kbd_input[KEYCODE_BUFFER_SIZE];
  #endif
  	char line_buf[LINE_BUF_SIZE];
  };
  #define G (*ptr_to_globals)
  #define top              (G.top               )
  #define ntop             (G.ntop              )
  #define sort_field       (G.sort_field        )
  #define inverted         (G.inverted          )
  #define smp_cpu_info     (G.smp_cpu_info      )
  #define initial_settings (G.initial_settings  )
  #define sort_function    (G.sort_function     )
  #define prev_hist        (G.prev_hist         )
  #define prev_hist_count  (G.prev_hist_count   )
  #define cur_jif          (G.cur_jif           )
  #define prev_jif         (G.prev_jif          )
  #define cpu_jif          (G.cpu_jif           )
  #define cpu_prev_jif     (G.cpu_prev_jif      )
  #define num_cpus         (G.num_cpus          )
  #define total_pcpu       (G.total_pcpu        )
  #define line_buf         (G.line_buf          )
  #define INIT_G() do { \
  	SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
  	BUILD_BUG_ON(LINE_BUF_SIZE <= 80); \
  } while (0)
  
  enum {
  	OPT_d = (1 << 0),
  	OPT_n = (1 << 1),
  	OPT_b = (1 << 2),
  	OPT_m = (1 << 3),
  	OPT_EOF = (1 << 4), /* pseudo: "we saw EOF in stdin" */
  };
  #define OPT_BATCH_MODE (option_mask32 & OPT_b)
  
  
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  static int pid_sort(top_status_t *P, top_status_t *Q)
  {
  	/* Buggy wrt pids with high bit set */
  	/* (linux pids are in [1..2^15-1]) */
  	return (Q->pid - P->pid);
  }
  #endif
  
  static int mem_sort(top_status_t *P, top_status_t *Q)
  {
  	/* We want to avoid unsigned->signed and truncation errors */
  	if (Q->vsz < P->vsz) return -1;
  	return Q->vsz != P->vsz; /* 0 if ==, 1 if > */
  }
  
  
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  
  static int pcpu_sort(top_status_t *P, top_status_t *Q)
  {
  	/* Buggy wrt ticks with high bit set */
  	/* Affects only processes for which ticks overflow */
  	return (int)Q->pcpu - (int)P->pcpu;
  }
  
  static int time_sort(top_status_t *P, top_status_t *Q)
  {
  	/* We want to avoid unsigned->signed and truncation errors */
  	if (Q->ticks < P->ticks) return -1;
  	return Q->ticks != P->ticks; /* 0 if ==, 1 if > */
  }
  
  static int mult_lvl_cmp(void* a, void* b)
  {
  	int i, cmp_val;
  
  	for (i = 0; i < SORT_DEPTH; i++) {
  		cmp_val = (*sort_function[i])(a, b);
  		if (cmp_val != 0)
  			break;
  	}
  	return inverted ? -cmp_val : cmp_val;
  }
  
  static NOINLINE int read_cpu_jiffy(FILE *fp, jiffy_counts_t *p_jif)
  {
  #if !ENABLE_FEATURE_TOP_SMP_CPU
  	static const char fmt[] ALIGN1 = "cpu %llu %llu %llu %llu %llu %llu %llu %llu";
  #else
  	static const char fmt[] ALIGN1 = "cp%*s %llu %llu %llu %llu %llu %llu %llu %llu";
  #endif
  	int ret;
  
  	if (!fgets(line_buf, LINE_BUF_SIZE, fp) || line_buf[0] != 'c' /* not "cpu" */)
  		return 0;
  	ret = sscanf(line_buf, fmt,
  			&p_jif->usr, &p_jif->nic, &p_jif->sys, &p_jif->idle,
  			&p_jif->iowait, &p_jif->irq, &p_jif->softirq,
  			&p_jif->steal);
  	if (ret >= 4) {
  		p_jif->total = p_jif->usr + p_jif->nic + p_jif->sys + p_jif->idle
  			+ p_jif->iowait + p_jif->irq + p_jif->softirq + p_jif->steal;
  		/* procps 2.x does not count iowait as busy time */
  		p_jif->busy = p_jif->total - p_jif->idle - p_jif->iowait;
  	}
  
  	return ret;
  }
  
  static void get_jiffy_counts(void)
  {
  	FILE* fp = xfopen_for_read("stat");
  
  	/* We need to parse cumulative counts even if SMP CPU display is on,
  	 * they are used to calculate per process CPU% */
  	prev_jif = cur_jif;
  	if (read_cpu_jiffy(fp, &cur_jif) < 4)
  		bb_error_msg_and_die("can't read '%s'", "/proc/stat");
  
  #if !ENABLE_FEATURE_TOP_SMP_CPU
  	fclose(fp);
  	return;
  #else
  	if (!smp_cpu_info) {
  		fclose(fp);
  		return;
  	}
  
  	if (!num_cpus) {
  		/* First time here. How many CPUs?
  		 * There will be at least 1 /proc/stat line with cpu%d
  		 */
  		while (1) {
  			cpu_jif = xrealloc_vector(cpu_jif, 1, num_cpus);
  			if (read_cpu_jiffy(fp, &cpu_jif[num_cpus]) <= 4)
  				break;
  			num_cpus++;
  		}
  		if (num_cpus == 0) /* /proc/stat with only "cpu ..." line?! */
  			smp_cpu_info = 0;
  
  		cpu_prev_jif = xzalloc(sizeof(cpu_prev_jif[0]) * num_cpus);
  
  		/* Otherwise the first per cpu display shows all 100% idles */
  		usleep(50000);
  	} else { /* Non first time invocation */
  		jiffy_counts_t *tmp;
  		int i;
  
  		/* First switch the sample pointers: no need to copy */
  		tmp = cpu_prev_jif;
  		cpu_prev_jif = cpu_jif;
  		cpu_jif = tmp;
  
  		/* Get the new samples */
  		for (i = 0; i < num_cpus; i++)
  			read_cpu_jiffy(fp, &cpu_jif[i]);
  	}
  #endif
  	fclose(fp);
  }
  
  static void do_stats(void)
  {
  	top_status_t *cur;
  	pid_t pid;
  	int i, last_i, n;
  	struct save_hist *new_hist;
  
  	get_jiffy_counts();
  	total_pcpu = 0;
  	/* total_vsz = 0; */
  	new_hist = xmalloc(sizeof(new_hist[0]) * ntop);
  	/*
  	 * Make a pass through the data to get stats.
  	 */
  	/* hist_iterations = 0; */
  	i = 0;
  	for (n = 0; n < ntop; n++) {
  		cur = top + n;
  
  		/*
  		 * Calculate time in cur process.  Time is sum of user time
  		 * and system time
  		 */
  		pid = cur->pid;
  		new_hist[n].ticks = cur->ticks;
  		new_hist[n].pid = pid;
  
  		/* find matching entry from previous pass */
  		cur->pcpu = 0;
  		/* do not start at index 0, continue at last used one
  		 * (brought hist_iterations from ~14000 down to 172) */
  		last_i = i;
  		if (prev_hist_count) do {
  			if (prev_hist[i].pid == pid) {
  				cur->pcpu = cur->ticks - prev_hist[i].ticks;
  				total_pcpu += cur->pcpu;
  				break;
  			}
  			i = (i+1) % prev_hist_count;
  			/* hist_iterations++; */
  		} while (i != last_i);
  		/* total_vsz += cur->vsz; */
  	}
  
  	/*
  	 * Save cur frame's information.
  	 */
  	free(prev_hist);
  	prev_hist = new_hist;
  	prev_hist_count = ntop;
  }
  
  #endif /* FEATURE_TOP_CPU_USAGE_PERCENTAGE */
  
  #if ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS && ENABLE_FEATURE_TOP_DECIMALS
  /* formats 7 char string (8 with terminating NUL) */
  static char *fmt_100percent_8(char pbuf[8], unsigned value, unsigned total)
  {
  	unsigned t;
  	if (value >= total) { /* 100% ? */
  		strcpy(pbuf, "  100% ");
  		return pbuf;
  	}
  	/* else generate " [N/space]N.N% " string */
  	value = 1000 * value / total;
  	t = value / 100;
  	value = value % 100;
  	pbuf[0] = ' ';
  	pbuf[1] = t ? t + '0' : ' ';
  	pbuf[2] = '0' + (value / 10);
  	pbuf[3] = '.';
  	pbuf[4] = '0' + (value % 10);
  	pbuf[5] = '%';
  	pbuf[6] = ' ';
  	pbuf[7] = '\0';
  	return pbuf;
  }
  #endif
  
  #if ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS
  static void display_cpus(int scr_width, char *scrbuf, int *lines_rem_p)
  {
  	/*
  	 * xxx% = (cur_jif.xxx - prev_jif.xxx) / (cur_jif.total - prev_jif.total) * 100%
  	 */
  	unsigned total_diff;
  	jiffy_counts_t *p_jif, *p_prev_jif;
  	int i;
  # if ENABLE_FEATURE_TOP_SMP_CPU
  	int n_cpu_lines;
  # endif
  
  	/* using (unsigned) casts to make operations cheaper */
  # define  CALC_TOTAL_DIFF do { \
  	total_diff = (unsigned)(p_jif->total - p_prev_jif->total); \
  	if (total_diff == 0) total_diff = 1; \
  } while (0)
  
  # if ENABLE_FEATURE_TOP_DECIMALS
  #  define CALC_STAT(xxx) char xxx[8]
  #  define SHOW_STAT(xxx) fmt_100percent_8(xxx, (unsigned)(p_jif->xxx - p_prev_jif->xxx), total_diff)
  #  define FMT "%s"
  # else
  #  define CALC_STAT(xxx) unsigned xxx = 100 * (unsigned)(p_jif->xxx - p_prev_jif->xxx) / total_diff
  #  define SHOW_STAT(xxx) xxx
  #  define FMT "%4u%% "
  # endif
  
  # if !ENABLE_FEATURE_TOP_SMP_CPU
  	{
  		i = 1;
  		p_jif = &cur_jif;
  		p_prev_jif = &prev_jif;
  # else
  	/* Loop thru CPU(s) */
  	n_cpu_lines = smp_cpu_info ? num_cpus : 1;
  	if (n_cpu_lines > *lines_rem_p)
  		n_cpu_lines = *lines_rem_p;
  
  	for (i = 0; i < n_cpu_lines; i++) {
  		p_jif = &cpu_jif[i];
  		p_prev_jif = &cpu_prev_jif[i];
  # endif
  		CALC_TOTAL_DIFF;
  
  		{ /* Need a block: CALC_STAT are declarations */
  			CALC_STAT(usr);
  			CALC_STAT(sys);
  			CALC_STAT(nic);
  			CALC_STAT(idle);
  			CALC_STAT(iowait);
  			CALC_STAT(irq);
  			CALC_STAT(softirq);
  			/*CALC_STAT(steal);*/
  
  			snprintf(scrbuf, scr_width,
  				/* Barely fits in 79 chars when in "decimals" mode. */
  # if ENABLE_FEATURE_TOP_SMP_CPU
  				"CPU%s:"FMT"usr"FMT"sys"FMT"nic"FMT"idle"FMT"io"FMT"irq"FMT"sirq",
  				(smp_cpu_info ? utoa(i) : ""),
  # else
  				"CPU:"FMT"usr"FMT"sys"FMT"nic"FMT"idle"FMT"io"FMT"irq"FMT"sirq",
  # endif
  				SHOW_STAT(usr), SHOW_STAT(sys), SHOW_STAT(nic), SHOW_STAT(idle),
  				SHOW_STAT(iowait), SHOW_STAT(irq), SHOW_STAT(softirq)
  				/*, SHOW_STAT(steal) - what is this 'steal' thing? */
  				/* I doubt anyone wants to know it */
  			);
  			puts(scrbuf);
  		}
  	}
  # undef SHOW_STAT
  # undef CALC_STAT
  # undef FMT
  	*lines_rem_p -= i;
  }
  #else  /* !ENABLE_FEATURE_TOP_CPU_GLOBAL_PERCENTS */
  # define display_cpus(scr_width, scrbuf, lines_rem) ((void)0)
  #endif
  
  enum {
  	MI_MEMTOTAL,
  	MI_MEMFREE,
  	MI_MEMSHARED,
  	MI_SHMEM,
  	MI_BUFFERS,
  	MI_CACHED,
  	MI_SWAPTOTAL,
  	MI_SWAPFREE,
  	MI_DIRTY,
  	MI_WRITEBACK,
  	MI_ANONPAGES,
  	MI_MAPPED,
  	MI_SLAB,
  	MI_MAX
  };
  
  static void parse_meminfo(unsigned long meminfo[MI_MAX])
  {
  	static const char fields[] ALIGN1 =
  		"MemTotal\0"
  		"MemFree\0"
  		"MemShared\0"
  		"Shmem\0"
  		"Buffers\0"
  		"Cached\0"
  		"SwapTotal\0"
  		"SwapFree\0"
  		"Dirty\0"
  		"Writeback\0"
  		"AnonPages\0"
  		"Mapped\0"
  		"Slab\0";
  	char buf[60]; /* actual lines we expect are ~30 chars or less */
  	FILE *f;
  	int i;
  
  	memset(meminfo, 0, sizeof(meminfo[0]) * MI_MAX);
  	f = xfopen_for_read("meminfo");
  	while (fgets(buf, sizeof(buf), f) != NULL) {
  		char *c = strchr(buf, ':');
  		if (!c)
  			continue;
  		*c = '\0';
  		i = index_in_strings(fields, buf);
  		if (i >= 0)
  			meminfo[i] = strtoul(c+1, NULL, 10);
  	}
  	fclose(f);
  }
  
  static unsigned long display_header(int scr_width, int *lines_rem_p)
  {
  	char scrbuf[100]; /* [80] was a bit too low on 8Gb ram box */
  	char *buf;
  	unsigned long meminfo[MI_MAX];
  
  	parse_meminfo(meminfo);
  
  	/* Output memory info */
  	if (scr_width > (int)sizeof(scrbuf))
  		scr_width = sizeof(scrbuf);
  	snprintf(scrbuf, scr_width,
  		"Mem: %luK used, %luK free, %luK shrd, %luK buff, %luK cached",
  		meminfo[MI_MEMTOTAL] - meminfo[MI_MEMFREE],
  		meminfo[MI_MEMFREE],
  		meminfo[MI_MEMSHARED] + meminfo[MI_SHMEM],
  		meminfo[MI_BUFFERS],
  		meminfo[MI_CACHED]);
  	/* Go to top & clear to the end of screen */
  	printf(OPT_BATCH_MODE ? "%s\n" : ESC"[H" ESC"[J" "%s\n", scrbuf);
  	(*lines_rem_p)--;
  
  	/* Display CPU time split as percentage of total time.
  	 * This displays either a cumulative line or one line per CPU.
  	 */
  	display_cpus(scr_width, scrbuf, lines_rem_p);
  
  	/* Read load average as a string */
  	buf = stpcpy(scrbuf, "Load average: ");
  	open_read_close("loadavg", buf, sizeof(scrbuf) - sizeof("Load average: "));
  	scrbuf[scr_width - 1] = '\0';
  	strchrnul(buf, '\n')[0] = '\0';
  	puts(scrbuf);
  	(*lines_rem_p)--;
  
  	return meminfo[MI_MEMTOTAL];
  }
  
  static NOINLINE void display_process_list(int lines_rem, int scr_width)
  {
  	enum {
  		BITS_PER_INT = sizeof(int) * 8
  	};
  
  	top_status_t *s;
  	char vsz_str_buf[8];
  	unsigned long total_memory = display_header(scr_width, &lines_rem); /* or use total_vsz? */
  	/* xxx_shift and xxx_scale variables allow us to replace
  	 * expensive divides with multiply and shift */
  	unsigned pmem_shift, pmem_scale, pmem_half;
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  	unsigned tmp_unsigned;
  	unsigned pcpu_shift, pcpu_scale, pcpu_half;
  	unsigned busy_jifs;
  #endif
  
  	/* what info of the processes is shown */
  	printf(OPT_BATCH_MODE ? "%.*s" : ESC"[7m" "%.*s" ESC"[m", scr_width,
  		"  PID  PPID USER     STAT   VSZ %VSZ"
  		IF_FEATURE_TOP_SMP_PROCESS(" CPU")
  		IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE(" %CPU")
  		" COMMAND");
  	lines_rem--;
  
  #if ENABLE_FEATURE_TOP_DECIMALS
  # define UPSCALE 1000
  # define CALC_STAT(name, val) div_t name = div((val), 10)
  # define SHOW_STAT(name) name.quot, '0'+name.rem
  # define FMT "%3u.%c"
  #else
  # define UPSCALE 100
  # define CALC_STAT(name, val) unsigned name = (val)
  # define SHOW_STAT(name) name
  # define FMT "%4u%%"
  #endif
  	/*
  	 * %VSZ = s->vsz/MemTotal
  	 */
  	pmem_shift = BITS_PER_INT-11;
  	pmem_scale = UPSCALE*(1U<<(BITS_PER_INT-11)) / total_memory;
  	/* s->vsz is in kb. we want (s->vsz * pmem_scale) to never overflow */
  	while (pmem_scale >= 512) {
  		pmem_scale /= 4;
  		pmem_shift -= 2;
  	}
  	pmem_half = (1U << pmem_shift) / (ENABLE_FEATURE_TOP_DECIMALS ? 20 : 2);
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  	busy_jifs = cur_jif.busy - prev_jif.busy;
  	/* This happens if there were lots of short-lived processes
  	 * between two top updates (e.g. compilation) */
  	if (total_pcpu < busy_jifs) total_pcpu = busy_jifs;
  
  	/*
  	 * CPU% = s->pcpu/sum(s->pcpu) * busy_cpu_ticks/total_cpu_ticks
  	 * (pcpu is delta of sys+user time between samples)
  	 */
  	/* (cur_jif.xxx - prev_jif.xxx) and s->pcpu are
  	 * in 0..~64000 range (HZ*update_interval).
  	 * we assume that unsigned is at least 32-bit.
  	 */
  	pcpu_shift = 6;
  	pcpu_scale = UPSCALE*64 * (uint16_t)busy_jifs;
  	if (pcpu_scale == 0)
  		pcpu_scale = 1;
  	while (pcpu_scale < (1U << (BITS_PER_INT-2))) {
  		pcpu_scale *= 4;
  		pcpu_shift += 2;
  	}
  	tmp_unsigned = (uint16_t)(cur_jif.total - prev_jif.total) * total_pcpu;
  	if (tmp_unsigned != 0)
  		pcpu_scale /= tmp_unsigned;
  	/* we want (s->pcpu * pcpu_scale) to never overflow */
  	while (pcpu_scale >= 1024) {
  		pcpu_scale /= 4;
  		pcpu_shift -= 2;
  	}
  	pcpu_half = (1U << pcpu_shift) / (ENABLE_FEATURE_TOP_DECIMALS ? 20 : 2);
  	/* printf(" pmem_scale=%u pcpu_scale=%u ", pmem_scale, pcpu_scale); */
  #endif
  
  	/* Ok, all preliminary data is ready, go through the list */
  	scr_width += 2; /* account for leading '\n' and trailing NUL */
  	if (lines_rem > ntop - G_scroll_ofs)
  		lines_rem = ntop - G_scroll_ofs;
  	s = top + G_scroll_ofs;
  	while (--lines_rem >= 0) {
  		unsigned col;
  		CALC_STAT(pmem, (s->vsz*pmem_scale + pmem_half) >> pmem_shift);
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  		CALC_STAT(pcpu, (s->pcpu*pcpu_scale + pcpu_half) >> pcpu_shift);
  #endif
  
  		if (s->vsz >= 100000)
  			sprintf(vsz_str_buf, "%6ldm", s->vsz/1024);
  		else
  			sprintf(vsz_str_buf, "%7lu", s->vsz);
  		/* PID PPID USER STAT VSZ %VSZ [%CPU] COMMAND */
  		col = snprintf(line_buf, scr_width,
  				"\n" "%5u%6u %-8.8s %s%s" FMT
  				IF_FEATURE_TOP_SMP_PROCESS(" %3d")
  				IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE(FMT)
  				" ",
  				s->pid, s->ppid, get_cached_username(s->uid),
  				s->state, vsz_str_buf,
  				SHOW_STAT(pmem)
  				IF_FEATURE_TOP_SMP_PROCESS(, s->last_seen_on_cpu)
  				IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE(, SHOW_STAT(pcpu))
  		);
  		if ((int)(col + 1) < scr_width)
  			read_cmdline(line_buf + col, scr_width - col, s->pid, s->comm);
  		fputs(line_buf, stdout);
  		/* printf(" %d/%d %lld/%lld", s->pcpu, total_pcpu,
  			cur_jif.busy - prev_jif.busy, cur_jif.total - prev_jif.total); */
  		s++;
  	}
  	/* printf(" %d", hist_iterations); */
  	bb_putchar(OPT_BATCH_MODE ? '\n' : '\r');
  	fflush_all();
  }
  #undef UPSCALE
  #undef SHOW_STAT
  #undef CALC_STAT
  #undef FMT
  
  static void clearmems(void)
  {
  	clear_username_cache();
  	free(top);
  	top = NULL;
  }
  
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  static void reset_term(void)
  {
  	if (!OPT_BATCH_MODE)
  		tcsetattr_stdin_TCSANOW(&initial_settings);
  }
  
  static void sig_catcher(int sig)
  {
  	reset_term();
  	kill_myself_with_sig(sig);
  }
  #endif /* FEATURE_TOP_INTERACTIVE */
  
  /*
   * TOPMEM support
   */
  
  typedef unsigned long mem_t;
  
  typedef struct topmem_status_t {
  	unsigned pid;
  	char comm[COMM_LEN];
  	/* vsz doesn't count /dev/xxx mappings except /dev/zero */
  	mem_t vsz     ;
  	mem_t vszrw   ;
  	mem_t rss     ;
  	mem_t rss_sh  ;
  	mem_t dirty   ;
  	mem_t dirty_sh;
  	mem_t stack   ;
  } topmem_status_t;
  
  enum { NUM_SORT_FIELD = 7 };
  
  #define topmem ((topmem_status_t*)top)
  
  #if ENABLE_FEATURE_TOPMEM
  
  static int topmem_sort(char *a, char *b)
  {
  	int n;
  	mem_t l, r;
  
  	n = offsetof(topmem_status_t, vsz) + (sort_field * sizeof(mem_t));
  	l = *(mem_t*)(a + n);
  	r = *(mem_t*)(b + n);
  	if (l == r) {
  		l = ((topmem_status_t*)a)->dirty;
  		r = ((topmem_status_t*)b)->dirty;
  	}
  	/* We want to avoid unsigned->signed and truncation errors */
  	/* l>r: -1, l=r: 0, l<r: 1 */
  	n = (l > r) ? -1 : (l != r);
  	return inverted ? -n : n;
  }
  
  /* display header info (meminfo / loadavg) */
  static void display_topmem_header(int scr_width, int *lines_rem_p)
  {
  	unsigned long meminfo[MI_MAX];
  
  	parse_meminfo(meminfo);
  
  	snprintf(line_buf, LINE_BUF_SIZE,
  		"Mem total:%lu anon:%lu map:%lu free:%lu",
  		meminfo[MI_MEMTOTAL],
  		meminfo[MI_ANONPAGES],
  		meminfo[MI_MAPPED],
  		meminfo[MI_MEMFREE]);
  	printf(OPT_BATCH_MODE ? "%.*s\n" : ESC"[H" ESC"[J" "%.*s\n", scr_width, line_buf);
  
  	snprintf(line_buf, LINE_BUF_SIZE,
  		" slab:%lu buf:%lu cache:%lu dirty:%lu write:%lu",
  		meminfo[MI_SLAB],
  		meminfo[MI_BUFFERS],
  		meminfo[MI_CACHED],
  		meminfo[MI_DIRTY],
  		meminfo[MI_WRITEBACK]);
  	printf("%.*s\n", scr_width, line_buf);
  
  	snprintf(line_buf, LINE_BUF_SIZE,
  		"Swap total:%lu free:%lu", // TODO: % used?
  		meminfo[MI_SWAPTOTAL],
  		meminfo[MI_SWAPFREE]);
  	printf("%.*s\n", scr_width, line_buf);
  
  	(*lines_rem_p) -= 3;
  }
  
  static void ulltoa6_and_space(unsigned long long ul, char buf[6])
  {
  	/* see http://en.wikipedia.org/wiki/Tera */
  	smart_ulltoa5(ul, buf, " mgtpezy")[0] = ' ';
  }
  
  static NOINLINE void display_topmem_process_list(int lines_rem, int scr_width)
  {
  #define HDR_STR "  PID   VSZ VSZRW   RSS (SHR) DIRTY (SHR) STACK"
  #define MIN_WIDTH sizeof(HDR_STR)
  	const topmem_status_t *s = topmem + G_scroll_ofs;
  	char *cp, ch;
  
  	display_topmem_header(scr_width, &lines_rem);
  
  	strcpy(line_buf, HDR_STR " COMMAND");
  	/* Mark the ^FIELD^ we sort by */
  	cp = &line_buf[5 + sort_field * 6];
  	ch = "^_"[inverted];
  	cp[6] = ch;
  	do *cp++ = ch; while (*cp == ' ');
  
  	printf(OPT_BATCH_MODE ? "%.*s" : ESC"[7m" "%.*s" ESC"[m", scr_width, line_buf);
  	lines_rem--;
  
  	if (lines_rem > ntop - G_scroll_ofs)
  		lines_rem = ntop - G_scroll_ofs;
  	while (--lines_rem >= 0) {
  		/* PID VSZ VSZRW RSS (SHR) DIRTY (SHR) COMMAND */
  		ulltoa6_and_space(s->pid     , &line_buf[0*6]);
  		ulltoa6_and_space(s->vsz     , &line_buf[1*6]);
  		ulltoa6_and_space(s->vszrw   , &line_buf[2*6]);
  		ulltoa6_and_space(s->rss     , &line_buf[3*6]);
  		ulltoa6_and_space(s->rss_sh  , &line_buf[4*6]);
  		ulltoa6_and_space(s->dirty   , &line_buf[5*6]);
  		ulltoa6_and_space(s->dirty_sh, &line_buf[6*6]);
  		ulltoa6_and_space(s->stack   , &line_buf[7*6]);
  		line_buf[8*6] = '\0';
  		if (scr_width > (int)MIN_WIDTH) {
  			read_cmdline(&line_buf[8*6], scr_width - MIN_WIDTH, s->pid, s->comm);
  		}
  		printf("\n""%.*s", scr_width, line_buf);
  		s++;
  	}
  	bb_putchar(OPT_BATCH_MODE ? '\n' : '\r');
  	fflush_all();
  #undef HDR_STR
  #undef MIN_WIDTH
  }
  
  #else
  void display_topmem_process_list(int lines_rem, int scr_width);
  int topmem_sort(char *a, char *b);
  #endif /* TOPMEM */
  
  /*
   * end TOPMEM support
   */
  
  enum {
  	TOP_MASK = 0
  		| PSSCAN_PID
  		| PSSCAN_PPID
  		| PSSCAN_VSZ
  		| PSSCAN_STIME
  		| PSSCAN_UTIME
  		| PSSCAN_STATE
  		| PSSCAN_COMM
  		| PSSCAN_CPU
  		| PSSCAN_UIDGID,
  	TOPMEM_MASK = 0
  		| PSSCAN_PID
  		| PSSCAN_SMAPS
  		| PSSCAN_COMM,
  	EXIT_MASK = (unsigned)-1,
  };
  
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  static unsigned handle_input(unsigned scan_mask, unsigned interval)
  {
  	if (option_mask32 & OPT_EOF) {
  		/* EOF on stdin ("top </dev/null") */
  		sleep(interval);
  		return scan_mask;
  	}
  
  	while (1) {
  		int32_t c;
  
  		c = read_key(STDIN_FILENO, G.kbd_input, interval * 1000);
  		if (c == -1 && errno != EAGAIN) {
  			/* error/EOF */
  			option_mask32 |= OPT_EOF;
  			break;
  		}
  		interval = 0;
  
  		if (c == initial_settings.c_cc[VINTR])
  			return EXIT_MASK;
  		if (c == initial_settings.c_cc[VEOF])
  			return EXIT_MASK;
  
  		if (c == KEYCODE_UP) {
  			G_scroll_ofs--;
  			goto normalize_ofs;
  		}
  		if (c == KEYCODE_DOWN) {
  			G_scroll_ofs++;
  			goto normalize_ofs;
  		}
  		if (c == KEYCODE_HOME) {
  			G_scroll_ofs = 0;
  			break;
  		}
  		if (c == KEYCODE_END) {
  			G_scroll_ofs = ntop - G.lines / 2;
  			goto normalize_ofs;
  		}
  		if (c == KEYCODE_PAGEUP) {
  			G_scroll_ofs -= G.lines / 2;
  			goto normalize_ofs;
  		}
  		if (c == KEYCODE_PAGEDOWN) {
  			G_scroll_ofs += G.lines / 2;
   normalize_ofs:
  			if (G_scroll_ofs >= ntop)
  				G_scroll_ofs = ntop - 1;
  			if (G_scroll_ofs < 0)
  				G_scroll_ofs = 0;
  			break;
  		}
  
  		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;)
  			sort_function[0] = mem_sort;
  # if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  			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
  		if (c == 'p') {
  			IF_FEATURE_TOPMEM(scan_mask = TOP_MASK;)
  			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') {
  			scan_mask = TOPMEM_MASK;
  			free(prev_hist);
  			prev_hist = NULL;
  			prev_hist_count = 0;
  			sort_field = (sort_field + 1) % NUM_SORT_FIELD;
  			continue;
  		}
  #  endif
  		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') {
  			/* User wants to toggle per cpu <> aggregate */
  			if (smp_cpu_info) {
  				free(cpu_prev_jif);
  				free(cpu_jif);
  				cpu_jif = &cur_jif;
  				cpu_prev_jif = &prev_jif;
  			} else {
  				/* Prepare for xrealloc() */
  				cpu_jif = cpu_prev_jif = NULL;
  			}
  			num_cpus = 0;
  			smp_cpu_info = !smp_cpu_info;
  			get_jiffy_counts();
  			continue;
  		}
  #  endif
  # endif
  		break; /* unknown key -> force refresh */
  	}
  
  	return scan_mask;
  }
  #endif
  
  //usage:#if ENABLE_FEATURE_SHOW_THREADS || ENABLE_FEATURE_TOP_SMP_CPU
  //usage:# define IF_SHOW_THREADS_OR_TOP_SMP(...) __VA_ARGS__
  //usage:#else
  //usage:# define IF_SHOW_THREADS_OR_TOP_SMP(...)
  //usage:#endif
  //usage:#define top_trivial_usage
  //usage:       "[-b] [-nCOUNT] [-dSECONDS]" IF_FEATURE_TOPMEM(" [-m]")
  //usage:#define top_full_usage "\n\n"
  //usage:       "Provide a view of process activity in real time."
  //usage:   "\n""Read the status of all processes from /proc each SECONDS"
  //usage:   "\n""and display a screenful of them."
  //usage:   "\n"
  //usage:	IF_FEATURE_TOP_INTERACTIVE(
  //usage:       "Keys:"
  //usage:   "\n""	N/M"
  //usage:                IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE("/P")
  //usage:                IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE("/T")
  //usage:           ": " IF_FEATURE_TOPMEM("show CPU usage, ") "sort by pid/mem"
  //usage:                IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE("/cpu")
  //usage:                IF_FEATURE_TOP_CPU_USAGE_PERCENTAGE("/time")
  //usage:	IF_FEATURE_TOPMEM(
  //usage:   "\n""	S: show memory"
  //usage:	)
  //usage:   "\n""	R: reverse sort"
  //usage:	IF_SHOW_THREADS_OR_TOP_SMP(
  //usage:   "\n""	"
  //usage:                IF_FEATURE_SHOW_THREADS("H: toggle threads")
  //usage:                IF_FEATURE_SHOW_THREADS(IF_FEATURE_TOP_SMP_CPU(", "))
  //usage:                IF_FEATURE_TOP_SMP_CPU("1: toggle SMP")
  //usage:	)
  //usage:   "\n""	Q,^C: exit"
  //usage:   "\n"
  //usage:   "\n""Options:"
  //usage:	)
  //usage:   "\n""	-b	Batch mode"
  //usage:   "\n""	-n N	Exit after N iterations"
  //usage:   "\n""	-d N	Delay between updates"
  //usage:	IF_FEATURE_TOPMEM(
  //usage:   "\n""	-m	Same as 's' key"
  //usage:	)
  
  /* Interactive testing:
   * echo sss | ./busybox top
   * - shows memory screen
   * echo sss | ./busybox top -bn1 >mem
   * - 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?
   */
  
  int top_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  int top_main(int argc UNUSED_PARAM, char **argv)
  {
  	int iterations;
  	unsigned col;
  	unsigned interval;
  	char *str_interval, *str_iterations;
  	unsigned scan_mask = TOP_MASK;
  
  	INIT_G();
  
  	interval = 5; /* default update interval is 5 seconds */
  	iterations = 0; /* infinite */
  #if ENABLE_FEATURE_TOP_SMP_CPU
  	/*num_cpus = 0;*/
  	/*smp_cpu_info = 0;*/  /* to start with show aggregate */
  	cpu_jif = &cur_jif;
  	cpu_prev_jif = &prev_jif;
  #endif
  
  	/* all args are options; -n NUM */
  	make_all_argv_opts(argv); /* options can be specified w/o dash */
  	col = getopt32(argv, "d:n:b"IF_FEATURE_TOPMEM("m"), &str_interval, &str_iterations);
  #if ENABLE_FEATURE_TOPMEM
  	if (col & OPT_m) /* -m (busybox specific) */
  		scan_mask = TOPMEM_MASK;
  #endif
  	if (col & OPT_d) {
  		/* work around for "-d 1" -> "-d -1" done by make_all_argv_opts() */
  		if (str_interval[0] == '-')
  			str_interval++;
  		/* Need to limit it to not overflow poll timeout */
  		interval = xatou16(str_interval);
  	}
  	if (col & OPT_n) {
  		if (str_iterations[0] == '-')
  			str_iterations++;
  		iterations = xatou(str_iterations);
  	}
  
  	/* change to /proc */
  	xchdir("/proc");
  
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  	sort_function[0] = pcpu_sort;
  	sort_function[1] = mem_sort;
  	sort_function[2] = time_sort;
  #else
  	sort_function[0] = mem_sort;
  #endif
  
  	if (OPT_BATCH_MODE) {
  		option_mask32 |= OPT_EOF;
  	}
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  	else {
  		/* Turn on unbuffered input; turn off echoing, ^C ^Z etc */
  		set_termios_to_raw(STDIN_FILENO, &initial_settings, TERMIOS_CLEAR_ISIG);
  		die_func = reset_term;
  	}
  
  	bb_signals(BB_FATAL_SIGS, sig_catcher);
  
  	/* Eat initial input, if any */
  	scan_mask = handle_input(scan_mask, 0);
  #endif
  
  	while (scan_mask != EXIT_MASK) {
  		procps_status_t *p = NULL;
  
  		if (OPT_BATCH_MODE) {
  			G.lines = INT_MAX;
  			col = LINE_BUF_SIZE - 2; /* +2 bytes for '\n', NUL */
  		} else {
  			G.lines = 24; /* default */
  			col = 79;
  			/* We output to stdout, we need size of stdout (not stdin)! */
  			get_terminal_width_height(STDOUT_FILENO, &col, &G.lines);
  			if (G.lines < 5 || col < 10) {
  				sleep(interval);
  				continue;
  			}
  			if (col > LINE_BUF_SIZE - 2)
  				col = LINE_BUF_SIZE - 2;
  		}
  
  		/* read process IDs & status for all the processes */
  		ntop = 0;
  		while ((p = procps_scan(p, scan_mask)) != NULL) {
  			int n;
  
  			IF_FEATURE_TOPMEM(if (scan_mask != TOPMEM_MASK)) {
  				n = ntop;
  				top = xrealloc_vector(top, 6, ntop++);
  				top[n].pid = p->pid;
  				top[n].ppid = p->ppid;
  				top[n].vsz = p->vsz;
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  				top[n].ticks = p->stime + p->utime;
  #endif
  				top[n].uid = p->uid;
  				strcpy(top[n].state, p->state);
  				strcpy(top[n].comm, p->comm);
  #if ENABLE_FEATURE_TOP_SMP_PROCESS
  				top[n].last_seen_on_cpu = p->last_seen_on_cpu;
  #endif
  			}
  #if ENABLE_FEATURE_TOPMEM
  			else { /* TOPMEM */
  				if (!(p->smaps.mapped_ro | p->smaps.mapped_rw))
  					continue; /* kernel threads are ignored */
  				n = ntop;
  				/* No bug here - top and topmem are the same */
  				top = xrealloc_vector(topmem, 6, ntop++);
  				strcpy(topmem[n].comm, p->comm);
  				topmem[n].pid      = p->pid;
  				topmem[n].vsz      = p->smaps.mapped_rw + p->smaps.mapped_ro;
  				topmem[n].vszrw    = p->smaps.mapped_rw;
  				topmem[n].rss_sh   = p->smaps.shared_clean + p->smaps.shared_dirty;
  				topmem[n].rss      = p->smaps.private_clean + p->smaps.private_dirty + topmem[n].rss_sh;
  				topmem[n].dirty    = p->smaps.private_dirty + p->smaps.shared_dirty;
  				topmem[n].dirty_sh = p->smaps.shared_dirty;
  				topmem[n].stack    = p->smaps.stack;
  			}
  #endif
  		} /* end of "while we read /proc" */
  		if (ntop == 0) {
  			bb_error_msg("no process info in /proc");
  			break;
  		}
  
  		IF_FEATURE_TOPMEM(if (scan_mask != TOPMEM_MASK)) {
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  			if (!prev_hist_count) {
  				do_stats();
  				usleep(100000);
  				clearmems();
  				continue;
  			}
  			do_stats();
  			/* TODO: we don't need to sort all 10000 processes, we need to find top 24! */
  			qsort(top, ntop, sizeof(top_status_t), (void*)mult_lvl_cmp);
  #else
  			qsort(top, ntop, sizeof(top_status_t), (void*)(sort_function[0]));
  #endif
  			display_process_list(G.lines, col);
  		}
  #if ENABLE_FEATURE_TOPMEM
  		else { /* TOPMEM */
  			qsort(topmem, ntop, sizeof(topmem_status_t), (void*)topmem_sort);
  			display_topmem_process_list(G.lines, col);
  		}
  #endif
  		clearmems();
  		if (iterations >= 0 && !--iterations)
  			break;
  #if !ENABLE_FEATURE_TOP_INTERACTIVE
  		sleep(interval);
  #else
  		scan_mask = handle_input(scan_mask, interval);
  #endif
  	} /* end of "while (not Q)" */
  
  	bb_putchar('\n');
  #if ENABLE_FEATURE_TOP_INTERACTIVE
  	reset_term();
  #endif
  	if (ENABLE_FEATURE_CLEAN_UP) {
  		clearmems();
  #if ENABLE_FEATURE_TOP_CPU_USAGE_PERCENTAGE
  		free(prev_hist);
  #endif
  	}
  	return EXIT_SUCCESS;
  }
  