freebsd-src/contrib/top/utils.c
1998-07-06 21:01:54 +00:00

488 lines
10 KiB
C

/*
* Top users/processes display for Unix
* Version 3
*
* This program may be freely redistributed,
* but this entire comment MUST remain intact.
*
* Copyright (c) 1984, 1989, William LeFebvre, Rice University
* Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
*/
/*
* This file contains various handy utilities used by top.
*/
#include "top.h"
#include "os.h"
int atoiwi(str)
char *str;
{
register int len;
len = strlen(str);
if (len != 0)
{
if (strncmp(str, "infinity", len) == 0 ||
strncmp(str, "all", len) == 0 ||
strncmp(str, "maximum", len) == 0)
{
return(Infinity);
}
else if (str[0] == '-')
{
return(Invalid);
}
else
{
return(atoi(str));
}
}
return(0);
}
/*
* itoa - convert integer (decimal) to ascii string for positive numbers
* only (we don't bother with negative numbers since we know we
* don't use them).
*/
/*
* How do we know that 16 will suffice?
* Because the biggest number that we will
* ever convert will be 2^32-1, which is 10
* digits.
*/
char *itoa(val)
register int val;
{
register char *ptr;
static char buffer[16]; /* result is built here */
/* 16 is sufficient since the largest number
we will ever convert will be 2^32-1,
which is 10 digits. */
ptr = buffer + sizeof(buffer);
*--ptr = '\0';
if (val == 0)
{
*--ptr = '0';
}
else while (val != 0)
{
*--ptr = (val % 10) + '0';
val /= 10;
}
return(ptr);
}
/*
* itoa7(val) - like itoa, except the number is right justified in a 7
* character field. This code is a duplication of itoa instead of
* a front end to a more general routine for efficiency.
*/
char *itoa7(val)
register int val;
{
register char *ptr;
static char buffer[16]; /* result is built here */
/* 16 is sufficient since the largest number
we will ever convert will be 2^32-1,
which is 10 digits. */
ptr = buffer + sizeof(buffer);
*--ptr = '\0';
if (val == 0)
{
*--ptr = '0';
}
else while (val != 0)
{
*--ptr = (val % 10) + '0';
val /= 10;
}
while (ptr > buffer + sizeof(buffer) - 7)
{
*--ptr = ' ';
}
return(ptr);
}
/*
* digits(val) - return number of decimal digits in val. Only works for
* positive numbers. If val <= 0 then digits(val) == 0.
*/
int digits(val)
int val;
{
register int cnt = 0;
while (val > 0)
{
cnt++;
val /= 10;
}
return(cnt);
}
/*
* strecpy(to, from) - copy string "from" into "to" and return a pointer
* to the END of the string "to".
*/
char *strecpy(to, from)
register char *to;
register char *from;
{
while ((*to++ = *from++) != '\0');
return(--to);
}
/*
* string_index(string, array) - find string in array and return index
*/
int string_index(string, array)
char *string;
char **array;
{
register int i = 0;
while (*array != NULL)
{
if (strcmp(string, *array) == 0)
{
return(i);
}
array++;
i++;
}
return(-1);
}
/*
* argparse(line, cntp) - parse arguments in string "line", separating them
* out into an argv-like array, and setting *cntp to the number of
* arguments encountered. This is a simple parser that doesn't understand
* squat about quotes.
*/
char **argparse(line, cntp)
char *line;
int *cntp;
{
register char *from;
register char *to;
register int cnt;
register int ch;
int length;
int lastch;
register char **argv;
char **argarray;
char *args;
/* unfortunately, the only real way to do this is to go thru the
input string twice. */
/* step thru the string counting the white space sections */
from = line;
lastch = cnt = length = 0;
while ((ch = *from++) != '\0')
{
length++;
if (ch == ' ' && lastch != ' ')
{
cnt++;
}
lastch = ch;
}
/* add three to the count: one for the initial "dummy" argument,
one for the last argument and one for NULL */
cnt += 3;
/* allocate a char * array to hold the pointers */
argarray = (char **)malloc(cnt * sizeof(char *));
/* allocate another array to hold the strings themselves */
args = (char *)malloc(length+2);
/* initialization for main loop */
from = line;
to = args;
argv = argarray;
lastch = '\0';
/* create a dummy argument to keep getopt happy */
*argv++ = to;
*to++ = '\0';
cnt = 2;
/* now build argv while copying characters */
*argv++ = to;
while ((ch = *from++) != '\0')
{
if (ch != ' ')
{
if (lastch == ' ')
{
*to++ = '\0';
*argv++ = to;
cnt++;
}
*to++ = ch;
}
lastch = ch;
}
*to++ = '\0';
/* set cntp and return the allocated array */
*cntp = cnt;
return(argarray);
}
/*
* percentages(cnt, out, new, old, diffs) - calculate percentage change
* between array "old" and "new", putting the percentages i "out".
* "cnt" is size of each array and "diffs" is used for scratch space.
* The array "old" is updated on each call.
* The routine assumes modulo arithmetic. This function is especially
* useful on BSD mchines for calculating cpu state percentages.
*/
long percentages(cnt, out, new, old, diffs)
int cnt;
int *out;
register long *new;
register long *old;
long *diffs;
{
register int i;
register long change;
register long total_change;
register long *dp;
long half_total;
/* initialization */
total_change = 0;
dp = diffs;
/* calculate changes for each state and the overall change */
for (i = 0; i < cnt; i++)
{
if ((change = *new - *old) < 0)
{
/* this only happens when the counter wraps */
change = (int)
((unsigned long)*new-(unsigned long)*old);
}
total_change += (*dp++ = change);
*old++ = *new++;
}
/* avoid divide by zero potential */
if (total_change == 0)
{
total_change = 1;
}
/* calculate percentages based on overall change, rounding up */
half_total = total_change / 2l;
/* Do not divide by 0. Causes Floating point exception */
if(total_change) {
for (i = 0; i < cnt; i++)
{
*out++ = (int)((*diffs++ * 1000 + half_total) / total_change);
}
}
/* return the total in case the caller wants to use it */
return(total_change);
}
/*
* errmsg(errnum) - return an error message string appropriate to the
* error number "errnum". This is a substitute for the System V
* function "strerror" with one important difference: the string
* returned by this function does NOT end in a newline!
* N.B.: there appears to be no reliable way to determine if
* "strerror" exists at compile time, so I make do by providing
* something of similar functionality.
*/
/* externs referenced by errmsg */
char *errmsg(errnum)
int errnum;
{
if (errnum > 0 && errnum < sys_nerr)
{
return((char *)sys_errlist[errnum]);
}
return("No error");
}
/* format_time(seconds) - format number of seconds into a suitable
* display that will fit within 6 characters. Note that this
* routine builds its string in a static area. If it needs
* to be called more than once without overwriting previous data,
* then we will need to adopt a technique similar to the
* one used for format_k.
*/
/* Explanation:
We want to keep the output within 6 characters. For low values we use
the format mm:ss. For values that exceed 999:59, we switch to a format
that displays hours and fractions: hhh.tH. For values that exceed
999.9, we use hhhh.t and drop the "H" designator. For values that
exceed 9999.9, we use "???".
*/
char *format_time(seconds)
long seconds;
{
register int value;
register int digit;
register char *ptr;
static char result[10];
/* sanity protection */
if (seconds < 0 || seconds > (99999l * 360l))
{
strcpy(result, " ???");
}
else if (seconds >= (1000l * 60l))
{
/* alternate (slow) method displaying hours and tenths */
sprintf(result, "%5.1fH", (double)seconds / (double)(60l * 60l));
/* It is possible that the sprintf took more than 6 characters.
If so, then the "H" appears as result[6]. If not, then there
is a \0 in result[6]. Either way, it is safe to step on.
*/
result[6] = '\0';
}
else
{
/* standard method produces MMM:SS */
/* we avoid printf as must as possible to make this quick */
sprintf(result, "%3ld:%02ld",
(long)(seconds / 60), (long)(seconds % 60));
}
return(result);
}
/*
* format_k(amt) - format a kilobyte memory value, returning a string
* suitable for display. Returns a pointer to a static
* area that changes each call. "amt" is converted to a
* string with a trailing "K". If "amt" is 10000 or greater,
* then it is formatted as megabytes (rounded) with a
* trailing "M".
*/
/*
* Compromise time. We need to return a string, but we don't want the
* caller to have to worry about freeing a dynamically allocated string.
* Unfortunately, we can't just return a pointer to a static area as one
* of the common uses of this function is in a large call to sprintf where
* it might get invoked several times. Our compromise is to maintain an
* array of strings and cycle thru them with each invocation. We make the
* array large enough to handle the above mentioned case. The constant
* NUM_STRINGS defines the number of strings in this array: we can tolerate
* up to NUM_STRINGS calls before we start overwriting old information.
* Keeping NUM_STRINGS a power of two will allow an intelligent optimizer
* to convert the modulo operation into something quicker. What a hack!
*/
#define NUM_STRINGS 8
char *format_k(amt)
int amt;
{
static char retarray[NUM_STRINGS][16];
static int index = 0;
register char *p;
register char *ret;
register char tag = 'K';
p = ret = retarray[index];
index = (index + 1) % NUM_STRINGS;
if (amt >= 10000)
{
amt = (amt + 512) / 1024;
tag = 'M';
if (amt >= 10000)
{
amt = (amt + 512) / 1024;
tag = 'G';
}
}
p = strecpy(p, itoa(amt));
*p++ = tag;
*p = '\0';
return(ret);
}
char *format_k2(amt)
int amt;
{
static char retarray[NUM_STRINGS][16];
static int index = 0;
register char *p;
register char *ret;
register char tag = 'K';
p = ret = retarray[index];
index = (index + 1) % NUM_STRINGS;
if (amt >= 100000)
{
amt = (amt + 512) / 1024;
tag = 'M';
if (amt >= 100000)
{
amt = (amt + 512) / 1024;
tag = 'G';
}
}
p = strecpy(p, itoa(amt));
*p++ = tag;
*p = '\0';
return(ret);
}