NetBSD/usr.bin/top/commands.c

520 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 the routines that implement some of the interactive
* mode commands. Note that some of the commands are implemented in-line
* in "main". This is necessary because they change the global state of
* "top" (i.e.: changing the number of processes to display).
*/
#include "os.h"
#include <ctype.h>
#include <signal.h>
#include <errno.h>
#include <sys/time.h>
#include <sys/resource.h>
#include "top.h"
#include "top.local.h"
#include "sigdesc.h" /* generated automatically */
#include "boolean.h"
#include "machine.h"
#include "utils.h"
extern int errno;
extern char *copyright;
/* imported from screen.c */
extern int overstrike;
int err_compar();
char *err_string();
/*
* show_help() - display the help screen; invoked in response to
* either 'h' or '?'.
*/
show_help(statics)
struct statics *statics;
{
printf("Top version %s, %s\n", version_string(), copyright);
fputs("\n\n\
A top users display for Unix\n\
\n\
These single-character commands are available:\n\
\n\
^L - redraw screen\n\
q - quit\n\
h or ? - help; show this text\n", stdout);
/* not all commands are availalbe with overstrike terminals */
if (overstrike)
{
fputs("\n\
Other commands are also available, but this terminal is not\n\
sophisticated enough to handle those commands gracefully.\n\n", stdout);
}
else
{
fputs("\
d - change number of displays to show\n\
e - list errors generated by last \"kill\" or \"renice\" command\n\
i - toggle the displaying of idle processes\n\
I - same as 'i'\n\
k - kill processes; send a signal to a list of processes\n\
n or # - change number of processes to display\n", stdout);
#ifdef ORDER
{
int i;
fputs("\
o - specify sort order (", stdout);
for (i = 0; statics->order_names[i] != NULL; i++)
printf("%s%s", i == 0 ? "" : ", ", statics->order_names[i]);
puts(")");
}
#endif
fputs("\
r - renice a process\n\
s - change number of seconds to delay between updates\n\
u - display processes for only one user (+ selects all users)\n\
\n\
\n", stdout);
}
}
/*
* Utility routines that help with some of the commands.
*/
char *next_field(str)
register char *str;
{
if ((str = strchr(str, ' ')) == NULL)
{
return(NULL);
}
*str = '\0';
while (*++str == ' ') /* loop */;
/* if there is nothing left of the string, return NULL */
/* This fix is dedicated to Greg Earle */
return(*str == '\0' ? NULL : str);
}
scanint(str, intp)
char *str;
int *intp;
{
register int val = 0;
register char ch;
/* if there is nothing left of the string, flag it as an error */
/* This fix is dedicated to Greg Earle */
if (*str == '\0')
{
return(-1);
}
while ((ch = *str++) != '\0')
{
if (isdigit(ch))
{
val = val * 10 + (ch - '0');
}
else if (isspace(ch))
{
break;
}
else
{
return(-1);
}
}
*intp = val;
return(0);
}
/*
* Some of the commands make system calls that could generate errors.
* These errors are collected up in an array of structures for later
* contemplation and display. Such routines return a string containing an
* error message, or NULL if no errors occurred. The next few routines are
* for manipulating and displaying these errors. We need an upper limit on
* the number of errors, so we arbitrarily choose 20.
*/
#define ERRMAX 20
struct errs /* structure for a system-call error */
{
int errnum; /* value of errno (that is, the actual error) */
char *arg; /* argument that caused the error */
};
static struct errs errs[ERRMAX];
static int errcnt;
static char *err_toomany = " too many errors occurred";
static char *err_listem =
" Many errors occurred. Press `e' to display the list of errors.";
/* These macros get used to reset and log the errors */
#define ERR_RESET errcnt = 0
#define ERROR(p, e) if (errcnt >= ERRMAX) \
{ \
return(err_toomany); \
} \
else \
{ \
errs[errcnt].arg = (p); \
errs[errcnt++].errnum = (e); \
}
/*
* err_string() - return an appropriate error string. This is what the
* command will return for displaying. If no errors were logged, then
* return NULL. The maximum length of the error string is defined by
* "STRMAX".
*/
#define STRMAX 80
char *err_string()
{
register struct errs *errp;
register int cnt = 0;
register int first = Yes;
register int currerr = -1;
int stringlen; /* characters still available in "string" */
static char string[STRMAX];
/* if there are no errors, return NULL */
if (errcnt == 0)
{
return(NULL);
}
/* sort the errors */
qsort((char *)errs, errcnt, sizeof(struct errs), err_compar);
/* need a space at the front of the error string */
string[0] = ' ';
string[1] = '\0';
stringlen = STRMAX - 2;
/* loop thru the sorted list, building an error string */
while (cnt < errcnt)
{
errp = &(errs[cnt++]);
if (errp->errnum != currerr)
{
if (currerr != -1)
{
if ((stringlen = str_adderr(string, stringlen, currerr)) < 2)
{
return(err_listem);
}
(void) strcat(string, "; "); /* we know there's more */
}
currerr = errp->errnum;
first = Yes;
}
if ((stringlen = str_addarg(string, stringlen, errp->arg, first)) ==0)
{
return(err_listem);
}
first = No;
}
/* add final message */
stringlen = str_adderr(string, stringlen, currerr);
/* return the error string */
return(stringlen == 0 ? err_listem : string);
}
/*
* str_adderr(str, len, err) - add an explanation of error "err" to
* the string "str".
*/
str_adderr(str, len, err)
char *str;
int len;
int err;
{
register char *msg;
register int msglen;
msg = err == 0 ? "Not a number" : errmsg(err);
msglen = strlen(msg) + 2;
if (len <= msglen)
{
return(0);
}
(void) strcat(str, ": ");
(void) strcat(str, msg);
return(len - msglen);
}
/*
* str_addarg(str, len, arg, first) - add the string argument "arg" to
* the string "str". This is the first in the group when "first"
* is set (indicating that a comma should NOT be added to the front).
*/
str_addarg(str, len, arg, first)
char *str;
int len;
char *arg;
int first;
{
register int arglen;
arglen = strlen(arg);
if (!first)
{
arglen += 2;
}
if (len <= arglen)
{
return(0);
}
if (!first)
{
(void) strcat(str, ", ");
}
(void) strcat(str, arg);
return(len - arglen);
}
/*
* err_compar(p1, p2) - comparison routine used by "qsort"
* for sorting errors.
*/
err_compar(p1, p2)
register struct errs *p1, *p2;
{
register int result;
if ((result = p1->errnum - p2->errnum) == 0)
{
return(strcmp(p1->arg, p2->arg));
}
return(result);
}
/*
* error_count() - return the number of errors currently logged.
*/
error_count()
{
return(errcnt);
}
/*
* show_errors() - display on stdout the current log of errors.
*/
show_errors()
{
register int cnt = 0;
register struct errs *errp = errs;
printf("%d error%s:\n\n", errcnt, errcnt == 1 ? "" : "s");
while (cnt++ < errcnt)
{
printf("%5s: %s\n", errp->arg,
errp->errnum == 0 ? "Not a number" : errmsg(errp->errnum));
errp++;
}
}
/*
* kill_procs(str) - send signals to processes, much like the "kill"
* command does; invoked in response to 'k'.
*/
char *kill_procs(str)
char *str;
{
register char *nptr;
int signum = SIGTERM; /* default */
int procnum;
struct sigdesc *sigp;
int uid;
/* reset error array */
ERR_RESET;
/* remember our uid */
uid = getuid();
/* skip over leading white space */
while (isspace(*str)) str++;
if (str[0] == '-')
{
/* explicit signal specified */
if ((nptr = next_field(str)) == NULL)
{
return(" kill: no processes specified");
}
if (isdigit(str[1]))
{
(void) scanint(str + 1, &signum);
if (signum <= 0 || signum >= NSIG)
{
return(" invalid signal number");
}
}
else
{
/* translate the name into a number */
for (sigp = sigdesc; sigp->name != NULL; sigp++)
{
if (strcmp(sigp->name, str + 1) == 0)
{
signum = sigp->number;
break;
}
}
/* was it ever found */
if (sigp->name == NULL)
{
return(" bad signal name");
}
}
/* put the new pointer in place */
str = nptr;
}
/* loop thru the string, killing processes */
do
{
if (scanint(str, &procnum) == -1)
{
ERROR(str, 0);
}
else
{
/* check process owner if we're not root */
if (uid && (uid != proc_owner(procnum)))
{
ERROR(str, EACCES);
}
/* go in for the kill */
else if (kill(procnum, signum) == -1)
{
/* chalk up an error */
ERROR(str, errno);
}
}
} while ((str = next_field(str)) != NULL);
/* return appropriate error string */
return(err_string());
}
/*
* renice_procs(str) - change the "nice" of processes, much like the
* "renice" command does; invoked in response to 'r'.
*/
char *renice_procs(str)
char *str;
{
register char negate;
int prio;
int procnum;
int uid;
ERR_RESET;
uid = getuid();
/* allow for negative priority values */
if ((negate = (*str == '-')) != 0)
{
/* move past the minus sign */
str++;
}
/* use procnum as a temporary holding place and get the number */
procnum = scanint(str, &prio);
/* negate if necessary */
if (negate)
{
prio = -prio;
}
#if defined(PRIO_MIN) && defined(PRIO_MAX)
/* check for validity */
if (procnum == -1 || prio < PRIO_MIN || prio > PRIO_MAX)
{
return(" bad priority value");
}
#endif
/* move to the first process number */
if ((str = next_field(str)) == NULL)
{
return(" no processes specified");
}
/* loop thru the process numbers, renicing each one */
do
{
if (scanint(str, &procnum) == -1)
{
ERROR(str, 0);
}
/* check process owner if we're not root */
else if (uid && (uid != proc_owner(procnum)))
{
ERROR(str, EACCES);
}
else if (setpriority(PRIO_PROCESS, procnum, prio) == -1)
{
ERROR(str, errno);
}
} while ((str = next_field(str)) != NULL);
/* return appropriate error string */
return(err_string());
}