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|
/* $OpenBSD: display.c,v 1.1 1997/08/14 14:00:21 downsj Exp $ */
/*
* 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 the routines that display information on the screen.
* Each section of the screen has two routines: one for initially writing
* all constant and dynamic text, and one for only updating the text that
* changes. The prefix "i_" is used on all the "initial" routines and the
* prefix "u_" is used for all the "updating" routines.
*
* ASSUMPTIONS:
* None of the "i_" routines use any of the termcap capabilities.
* In this way, those routines can be safely used on terminals that
* have minimal (or nonexistant) terminal capabilities.
*
* The routines are called in this order: *_loadave, i_timeofday,
* *_procstates, *_cpustates, *_memory, *_message, *_header,
* *_process, u_endscreen.
*/
#include "os.h"
#include <ctype.h>
#include <time.h>
#include "screen.h" /* interface to screen package */
#include "layout.h" /* defines for screen position layout */
#include "display.h"
#include "top.h"
#include "top.local.h"
#include "boolean.h"
#include "machine.h" /* we should eliminate this!!! */
#include "utils.h"
#ifdef DEBUG
FILE *debug;
#endif
/* imported from screen.c */
extern int overstrike;
static int lmpid = 0;
static int last_hi = 0; /* used in u_process and u_endscreen */
static int lastline = 0;
static int display_width = MAX_COLS;
#define lineindex(l) ((l)*display_width)
char *printable();
/* things initialized by display_init and used thruout */
/* buffer of proc information lines for display updating */
char *screenbuf = NULL;
static char **procstate_names;
static char **cpustate_names;
static char **memory_names;
static int num_procstates;
static int num_cpustates;
static int num_memory;
static int *lprocstates;
static int *lcpustates;
static int *lmemory;
static int *cpustate_columns;
static int cpustate_total_length;
static enum { OFF, ON, ERASE } header_status = ON;
static int string_count();
static void summary_format();
static void line_update();
int display_resize()
{
register int lines;
/* first, deallocate any previous buffer that may have been there */
if (screenbuf != NULL)
{
free(screenbuf);
}
/* calculate the current dimensions */
/* if operating in "dumb" mode, we only need one line */
lines = smart_terminal ? screen_length - Header_lines : 1;
/* we don't want more than MAX_COLS columns, since the machine-dependent
modules make static allocations based on MAX_COLS and we don't want
to run off the end of their buffers */
display_width = screen_width;
if (display_width >= MAX_COLS)
{
display_width = MAX_COLS - 1;
}
/* now, allocate space for the screen buffer */
screenbuf = (char *)malloc(lines * display_width);
if (screenbuf == (char *)NULL)
{
/* oops! */
return(-1);
}
/* return number of lines available */
/* for dumb terminals, pretend like we can show any amount */
return(smart_terminal ? lines : Largest);
}
int display_init(statics)
struct statics *statics;
{
register int lines;
register char **pp;
register int *ip;
register int i;
/* call resize to do the dirty work */
lines = display_resize();
/* only do the rest if we need to */
if (lines > -1)
{
/* save pointers and allocate space for names */
procstate_names = statics->procstate_names;
num_procstates = string_count(procstate_names);
lprocstates = (int *)malloc(num_procstates * sizeof(int));
cpustate_names = statics->cpustate_names;
num_cpustates = string_count(cpustate_names);
lcpustates = (int *)malloc(num_cpustates * sizeof(int));
cpustate_columns = (int *)malloc(num_cpustates * sizeof(int));
memory_names = statics->memory_names;
num_memory = string_count(memory_names);
lmemory = (int *)malloc(num_memory * sizeof(int));
/* calculate starting columns where needed */
cpustate_total_length = 0;
pp = cpustate_names;
ip = cpustate_columns;
while (*pp != NULL)
{
if ((i = strlen(*pp++)) > 0)
{
*ip++ = cpustate_total_length;
cpustate_total_length += i + 8;
}
}
}
/* return number of lines available */
return(lines);
}
i_loadave(mpid, avenrun)
int mpid;
double *avenrun;
{
register int i;
/* i_loadave also clears the screen, since it is first */
clear();
/* mpid == -1 implies this system doesn't have an _mpid */
if (mpid != -1)
{
printf("last pid: %5d; ", mpid);
}
printf("load averages");
for (i = 0; i < 3; i++)
{
printf("%c %5.2f",
i == 0 ? ':' : ',',
avenrun[i]);
}
lmpid = mpid;
}
u_loadave(mpid, avenrun)
int mpid;
double *avenrun;
{
register int i;
if (mpid != -1)
{
/* change screen only when value has really changed */
if (mpid != lmpid)
{
Move_to(x_lastpid, y_lastpid);
printf("%5d", mpid);
lmpid = mpid;
}
/* i remembers x coordinate to move to */
i = x_loadave;
}
else
{
i = x_loadave_nompid;
}
/* move into position for load averages */
Move_to(i, y_loadave);
/* display new load averages */
/* we should optimize this and only display changes */
for (i = 0; i < 3; i++)
{
printf("%s%5.2f",
i == 0 ? "" : ", ",
avenrun[i]);
}
}
i_timeofday(tod)
time_t *tod;
{
/*
* Display the current time.
* "ctime" always returns a string that looks like this:
*
* Sun Sep 16 01:03:52 1973
* 012345678901234567890123
* 1 2
*
* We want indices 11 thru 18 (length 8).
*/
if (smart_terminal)
{
Move_to(screen_width - 8, 0);
}
else
{
fputs(" ", stdout);
}
#ifdef DEBUG
{
char *foo;
foo = ctime(tod);
fputs(foo, stdout);
}
#endif
printf("%-8.8s\n", &(ctime(tod)[11]));
lastline = 1;
}
static int ltotal = 0;
static char procstates_buffer[128];
/*
* *_procstates(total, brkdn, names) - print the process summary line
*
* Assumptions: cursor is at the beginning of the line on entry
* lastline is valid
*/
i_procstates(total, brkdn)
int total;
int *brkdn;
{
register int i;
/* write current number of processes and remember the value */
printf("%d processes:", total);
ltotal = total;
/* put out enough spaces to get to column 15 */
i = digits(total);
while (i++ < 4)
{
putchar(' ');
}
/* format and print the process state summary */
summary_format(procstates_buffer, brkdn, procstate_names);
fputs(procstates_buffer, stdout);
/* save the numbers for next time */
memcpy(lprocstates, brkdn, num_procstates * sizeof(int));
}
u_procstates(total, brkdn)
int total;
int *brkdn;
{
static char new[128];
register int i;
/* update number of processes only if it has changed */
if (ltotal != total)
{
/* move and overwrite */
#if (x_procstate == 0)
Move_to(x_procstate, y_procstate);
#else
/* cursor is already there...no motion needed */
/* assert(lastline == 1); */
#endif
printf("%d", total);
/* if number of digits differs, rewrite the label */
if (digits(total) != digits(ltotal))
{
fputs(" processes:", stdout);
/* put out enough spaces to get to column 15 */
i = digits(total);
while (i++ < 4)
{
putchar(' ');
}
/* cursor may end up right where we want it!!! */
}
/* save new total */
ltotal = total;
}
/* see if any of the state numbers has changed */
if (memcmp(lprocstates, brkdn, num_procstates * sizeof(int)) != 0)
{
/* format and update the line */
summary_format(new, brkdn, procstate_names);
line_update(procstates_buffer, new, x_brkdn, y_brkdn);
memcpy(lprocstates, brkdn, num_procstates * sizeof(int));
}
}
/*
* *_cpustates(states, names) - print the cpu state percentages
*
* Assumptions: cursor is on the PREVIOUS line
*/
static int cpustates_column;
/* cpustates_tag() calculates the correct tag to use to label the line */
char *cpustates_tag()
{
register char *use;
static char *short_tag = "CPU: ";
static char *long_tag = "CPU states: ";
/* if length + strlen(long_tag) >= screen_width, then we have to
use the shorter tag (we subtract 2 to account for ": ") */
if (cpustate_total_length + (int)strlen(long_tag) - 2 >= screen_width)
{
use = short_tag;
}
else
{
use = long_tag;
}
/* set cpustates_column accordingly then return result */
cpustates_column = strlen(use);
return(use);
}
i_cpustates(states)
register int *states;
{
register int i = 0;
register int value;
register char **names = cpustate_names;
register char *thisname;
/* print tag and bump lastline */
printf("\n%s", cpustates_tag());
lastline++;
/* now walk thru the names and print the line */
while ((thisname = *names++) != NULL)
{
if (*thisname != '\0')
{
/* retrieve the value and remember it */
value = *states++;
/* if percentage is >= 1000, print it as 100% */
printf((value >= 1000 ? "%s%4.0f%% %s" : "%s%4.1f%% %s"),
i++ == 0 ? "" : ", ",
((float)value)/10.,
thisname);
}
}
/* copy over values into "last" array */
memcpy(lcpustates, states, num_cpustates * sizeof(int));
}
u_cpustates(states)
register int *states;
{
register int value;
register char **names = cpustate_names;
register char *thisname;
register int *lp;
register int *colp;
Move_to(cpustates_column, y_cpustates);
lastline = y_cpustates;
lp = lcpustates;
colp = cpustate_columns;
/* we could be much more optimal about this */
while ((thisname = *names++) != NULL)
{
if (*thisname != '\0')
{
/* did the value change since last time? */
if (*lp != *states)
{
/* yes, move and change */
Move_to(cpustates_column + *colp, y_cpustates);
lastline = y_cpustates;
/* retrieve value and remember it */
value = *states;
/* if percentage is >= 1000, print it as 100% */
printf((value >= 1000 ? "%4.0f" : "%4.1f"),
((double)value)/10.);
/* remember it for next time */
*lp = *states;
}
}
/* increment and move on */
lp++;
states++;
colp++;
}
}
z_cpustates()
{
register int i = 0;
register char **names = cpustate_names;
register char *thisname;
register int *lp;
/* show tag and bump lastline */
printf("\n%s", cpustates_tag());
lastline++;
while ((thisname = *names++) != NULL)
{
if (*thisname != '\0')
{
printf("%s %% %s", i++ == 0 ? "" : ", ", thisname);
}
}
/* fill the "last" array with all -1s, to insure correct updating */
lp = lcpustates;
i = num_cpustates;
while (--i >= 0)
{
*lp++ = -1;
}
}
/*
* *_memory(stats) - print "Memory: " followed by the memory summary string
*
* Assumptions: cursor is on "lastline"
* for i_memory ONLY: cursor is on the previous line
*/
char memory_buffer[MAX_COLS];
i_memory(stats)
int *stats;
{
fputs("\nMemory: ", stdout);
lastline++;
/* format and print the memory summary */
summary_format(memory_buffer, stats, memory_names);
fputs(memory_buffer, stdout);
}
u_memory(stats)
int *stats;
{
static char new[MAX_COLS];
/* format the new line */
summary_format(new, stats, memory_names);
line_update(memory_buffer, new, x_mem, y_mem);
}
/*
* *_message() - print the next pending message line, or erase the one
* that is there.
*
* Note that u_message is (currently) the same as i_message.
*
* Assumptions: lastline is consistent
*/
/*
* i_message is funny because it gets its message asynchronously (with
* respect to screen updates).
*/
static char next_msg[MAX_COLS + 5];
static int msglen = 0;
/* Invariant: msglen is always the length of the message currently displayed
on the screen (even when next_msg doesn't contain that message). */
i_message()
{
while (lastline < y_message)
{
fputc('\n', stdout);
lastline++;
}
if (next_msg[0] != '\0')
{
standout(next_msg);
msglen = strlen(next_msg);
next_msg[0] = '\0';
}
else if (msglen > 0)
{
(void) clear_eol(msglen);
msglen = 0;
}
}
u_message()
{
i_message();
}
static int header_length;
/*
* *_header(text) - print the header for the process area
*
* Assumptions: cursor is on the previous line and lastline is consistent
*/
i_header(text)
char *text;
{
header_length = strlen(text);
if (header_status == ON)
{
putchar('\n');
fputs(text, stdout);
lastline++;
}
else if (header_status == ERASE)
{
header_status = OFF;
}
}
/*ARGSUSED*/
u_header(text)
char *text; /* ignored */
{
if (header_status == ERASE)
{
putchar('\n');
lastline++;
clear_eol(header_length);
header_status = OFF;
}
}
/*
* *_process(line, thisline) - print one process line
*
* Assumptions: lastline is consistent
*/
i_process(line, thisline)
int line;
char *thisline;
{
register char *p;
register char *base;
/* make sure we are on the correct line */
while (lastline < y_procs + line)
{
putchar('\n');
lastline++;
}
/* truncate the line to conform to our current screen width */
thisline[display_width] = '\0';
/* write the line out */
fputs(thisline, stdout);
/* copy it in to our buffer */
base = smart_terminal ? screenbuf + lineindex(line) : screenbuf;
p = strecpy(base, thisline);
/* zero fill the rest of it */
memzero(p, display_width - (p - base));
}
u_process(line, newline)
int line;
char *newline;
{
register char *optr;
register int screen_line = line + Header_lines;
register char *bufferline;
/* remember a pointer to the current line in the screen buffer */
bufferline = &screenbuf[lineindex(line)];
/* truncate the line to conform to our current screen width */
newline[display_width] = '\0';
/* is line higher than we went on the last display? */
if (line >= last_hi)
{
/* yes, just ignore screenbuf and write it out directly */
/* get positioned on the correct line */
if (screen_line - lastline == 1)
{
putchar('\n');
lastline++;
}
else
{
Move_to(0, screen_line);
lastline = screen_line;
}
/* now write the line */
fputs(newline, stdout);
/* copy it in to the buffer */
optr = strecpy(bufferline, newline);
/* zero fill the rest of it */
memzero(optr, display_width - (optr - bufferline));
}
else
{
line_update(bufferline, newline, 0, line + Header_lines);
}
}
u_endscreen(hi)
register int hi;
{
register int screen_line = hi + Header_lines;
register int i;
if (smart_terminal)
{
if (hi < last_hi)
{
/* need to blank the remainder of the screen */
/* but only if there is any screen left below this line */
if (lastline + 1 < screen_length)
{
/* efficiently move to the end of currently displayed info */
if (screen_line - lastline < 5)
{
while (lastline < screen_line)
{
putchar('\n');
lastline++;
}
}
else
{
Move_to(0, screen_line);
lastline = screen_line;
}
if (clear_to_end)
{
/* we can do this the easy way */
putcap(clear_to_end);
}
else
{
/* use clear_eol on each line */
i = hi;
while ((void) clear_eol(strlen(&screenbuf[lineindex(i++)])), i < last_hi)
{
putchar('\n');
}
}
}
}
last_hi = hi;
/* move the cursor to a pleasant place */
Move_to(x_idlecursor, y_idlecursor);
lastline = y_idlecursor;
}
else
{
/* separate this display from the next with some vertical room */
fputs("\n\n", stdout);
}
}
display_header(t)
int t;
{
if (t)
{
header_status = ON;
}
else if (header_status == ON)
{
header_status = ERASE;
}
}
/*VARARGS2*/
new_message(type, msgfmt, a1, a2, a3)
int type;
char *msgfmt;
caddr_t a1, a2, a3;
{
register int i;
/* first, format the message */
(void) snprintf(next_msg, sizeof(next_msg), msgfmt, a1, a2, a3);
if (msglen > 0)
{
/* message there already -- can we clear it? */
if (!overstrike)
{
/* yes -- write it and clear to end */
i = strlen(next_msg);
if ((type & MT_delayed) == 0)
{
type & MT_standout ? standout(next_msg) :
fputs(next_msg, stdout);
(void) clear_eol(msglen - i);
msglen = i;
next_msg[0] = '\0';
}
}
}
else
{
if ((type & MT_delayed) == 0)
{
type & MT_standout ? standout(next_msg) : fputs(next_msg, stdout);
msglen = strlen(next_msg);
next_msg[0] = '\0';
}
}
}
clear_message()
{
if (clear_eol(msglen) == 1)
{
putchar('\r');
}
}
readline(buffer, size, numeric)
char *buffer;
int size;
int numeric;
{
register char *ptr = buffer;
register char ch;
register char cnt = 0;
register char maxcnt = 0;
/* allow room for null terminator */
size -= 1;
/* read loop */
while ((fflush(stdout), read(0, ptr, 1) > 0))
{
/* newline means we are done */
if ((ch = *ptr) == '\n')
{
break;
}
/* handle special editing characters */
if (ch == ch_kill)
{
/* kill line -- account for overstriking */
if (overstrike)
{
msglen += maxcnt;
}
/* return null string */
*buffer = '\0';
putchar('\r');
return(-1);
}
else if (ch == ch_erase)
{
/* erase previous character */
if (cnt <= 0)
{
/* none to erase! */
putchar('\7');
}
else
{
fputs("\b \b", stdout);
ptr--;
cnt--;
}
}
/* check for character validity and buffer overflow */
else if (cnt == size || (numeric && !isdigit(ch)) ||
!isprint(ch))
{
/* not legal */
putchar('\7');
}
else
{
/* echo it and store it in the buffer */
putchar(ch);
ptr++;
cnt++;
if (cnt > maxcnt)
{
maxcnt = cnt;
}
}
}
/* all done -- null terminate the string */
*ptr = '\0';
/* account for the extra characters in the message area */
/* (if terminal overstrikes, remember the furthest they went) */
msglen += overstrike ? maxcnt : cnt;
/* return either inputted number or string length */
putchar('\r');
return(cnt == 0 ? -1 : numeric ? atoi(buffer) : cnt);
}
/* internal support routines */
static int string_count(pp)
register char **pp;
{
register int cnt;
cnt = 0;
while (*pp++ != NULL)
{
cnt++;
}
return(cnt);
}
static void summary_format(str, numbers, names)
char *str;
int *numbers;
register char **names;
{
register char *p;
register int num;
register char *thisname;
register int useM = No;
/* format each number followed by its string */
p = str;
while ((thisname = *names++) != NULL)
{
/* get the number to format */
num = *numbers++;
/* display only non-zero numbers */
if (num > 0)
{
/* is this number in kilobytes? */
if (thisname[0] == 'K')
{
/* yes: format it as a memory value */
p = strecpy(p, format_k(num));
/* skip over the K, since it was included by format_k */
p = strecpy(p, thisname+1);
}
else
{
p = strecpy(p, itoa(num));
p = strecpy(p, thisname);
}
}
/* ignore negative numbers, but display corresponding string */
else if (num < 0)
{
p = strecpy(p, thisname);
}
}
/* if the last two characters in the string are ", ", delete them */
p -= 2;
if (p >= str && p[0] == ',' && p[1] == ' ')
{
*p = '\0';
}
}
static void line_update(old, new, start, line)
register char *old;
register char *new;
int start;
int line;
{
register int ch;
register int diff;
register int newcol = start + 1;
register int lastcol = start;
char cursor_on_line = No;
char *current;
/* compare the two strings and only rewrite what has changed */
current = old;
#ifdef DEBUG
fprintf(debug, "line_update, starting at %d\n", start);
fputs(old, debug);
fputc('\n', debug);
fputs(new, debug);
fputs("\n-\n", debug);
#endif
/* start things off on the right foot */
/* this is to make sure the invariants get set up right */
if ((ch = *new++) != *old)
{
if (line - lastline == 1 && start == 0)
{
putchar('\n');
}
else
{
Move_to(start, line);
}
cursor_on_line = Yes;
putchar(ch);
*old = ch;
lastcol = 1;
}
old++;
/*
* main loop -- check each character. If the old and new aren't the
* same, then update the display. When the distance from the
* current cursor position to the new change is small enough,
* the characters that belong there are written to move the
* cursor over.
*
* Invariants:
* lastcol is the column where the cursor currently is sitting
* (always one beyond the end of the last mismatch).
*/
do /* yes, a do...while */
{
if ((ch = *new++) != *old)
{
/* new character is different from old */
/* make sure the cursor is on top of this character */
diff = newcol - lastcol;
if (diff > 0)
{
/* some motion is required--figure out which is shorter */
if (diff < 6 && cursor_on_line)
{
/* overwrite old stuff--get it out of the old buffer */
printf("%.*s", diff, ¤t[lastcol-start]);
}
else
{
/* use cursor addressing */
Move_to(newcol, line);
cursor_on_line = Yes;
}
/* remember where the cursor is */
lastcol = newcol + 1;
}
else
{
/* already there, update position */
lastcol++;
}
/* write what we need to */
if (ch == '\0')
{
/* at the end--terminate with a clear-to-end-of-line */
(void) clear_eol(strlen(old));
}
else
{
/* write the new character */
putchar(ch);
}
/* put the new character in the screen buffer */
*old = ch;
}
/* update working column and screen buffer pointer */
newcol++;
old++;
} while (ch != '\0');
/* zero out the rest of the line buffer -- MUST BE DONE! */
diff = display_width - newcol;
if (diff > 0)
{
memzero(old, diff);
}
/* remember where the current line is */
if (cursor_on_line)
{
lastline = line;
}
}
/*
* printable(str) - make the string pointed to by "str" into one that is
* printable (i.e.: all ascii), by converting all non-printable
* characters into '?'. Replacements are done in place and a pointer
* to the original buffer is returned.
*/
char *printable(str)
char *str;
{
register char *ptr;
register char ch;
ptr = str;
while ((ch = *ptr) != '\0')
{
if (!isprint(ch))
{
*ptr = '?';
}
ptr++;
}
return(str);
}
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