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/*
* A swapon(8)/swapoff(8) for Linux 0.99.
* swapon.c,v 1.1.1.1 1993/11/18 08:40:51 jrs Exp
* Added '-s' (Summary option) <Vincent.Renardias@waw.com> 02/1997.
*/
#include <stdlib.h>
#include <stdio.h>
#include <getopt.h>
#include <string.h>
#include <mntent.h>
#include <errno.h>
#include <sys/stat.h>
#include "swap_constants.h"
#include "swapargs.h"
#define streq(s, t) (strcmp ((s), (t)) == 0)
#define _PATH_FSTAB "/etc/fstab"
#define PROC_SWAPS "/proc/swaps"
#define SWAPON_NEEDS_TWO_ARGS
/* Nonzero for chatty (-v). This is a nonstandard flag (not in BSD). */
int verbose = 0;
int priority = -1; /* non-prioritized swap by default */
extern char version[];
static char *program_name;
static struct option longopts[] =
{
{ "all", 0, 0, 'a' },
{ "help", 0, 0, 'h' },
{ "priority", required_argument, 0, 'p' },
{ "summary", 0, 0, 's' },
{ "verbose", 0, 0, 'v' },
{ "version", 0, 0, 'V' },
{ NULL, 0, 0, 0 }
};
const char *usage_string = "\
usage: %s [-hV]\n\
%s -a [-v]\n\
%s [-v] [-p priority] special ...\n\
%s [-s]\n\
";
static void
usage (FILE *fp, int n)
{
fprintf (fp, usage_string, program_name, program_name, program_name, program_name);
exit (n);
}
#ifdef SWAPON_HAS_TWO_ARGS
#define SWAPON_NEEDS_TWO_ARGS
#endif
#ifdef SWAPON_NEEDS_TWO_ARGS
#ifdef SWAPON_HAS_TWO_ARGS
/* libc is OK */
#include <unistd.h>
#else
/* We want a swapon with two args, but have an old libc.
Build the kernel call by hand. */
#include <linux/unistd.h>
static
_syscall2(int, swapon, const char *, path, int, flags);
static
_syscall1(int, swapoff, const char *, path);
#endif
#else
/* just do as libc says */
#include <unistd.h>
#endif
static int
swap (const char *special, int prio)
{
int status;
struct stat st;
if (verbose)
printf("%s on %s\n", program_name, special);
if (streq (program_name, "swapon")) {
if (stat(special, &st) < 0) {
fprintf (stderr, "swapon: cannot stat %s: %s\n", special, strerror (errno));
return -1;
}
if ((st.st_mode & 07077) != 0) {
fprintf(stderr, "swapon: warning: %s has insecure permissions %04o, "
"0600 suggested\n", special, st.st_mode & 07777);
}
/* test for holes by LBT */
if (S_ISREG(st.st_mode)) {
if (st.st_blocks * 512 < st.st_size) {
fprintf(stderr,
"swapon: Skipping file %s - it appears to have holes.\n",
special);
return -1;
}
}
#ifdef SWAPON_NEEDS_TWO_ARGS
{
int flags = 0;
#ifdef SWAP_FLAG_PREFER
if (prio >= 0) {
if (prio > SWAP_FLAG_PRIO_MASK)
prio = SWAP_FLAG_PRIO_MASK;
flags = SWAP_FLAG_PREFER
| ((prio & SWAP_FLAG_PRIO_MASK) << SWAP_FLAG_PRIO_SHIFT);
}
#endif
status = swapon (special, flags);
}
#else
status = swapon (special);
#endif
} else
status = swapoff (special);
if (status < 0)
fprintf (stderr, "%s: %s: %s\n", program_name, special, strerror (errno));
return status;
}
static int
display_summary(void)
{
FILE *swaps;
char line[200] ;
if ((swaps = fopen(PROC_SWAPS, "r")) == NULL) {
fprintf (stderr, "%s: %s: %s\n", program_name, PROC_SWAPS,
strerror (errno));
return -1 ;
}
while ( fgets(line, sizeof(line), swaps))
printf ("%s", line);
return 0 ;
}
int
main (int argc, char *argv[])
{
struct mntent *fstab;
int status;
int all = 0;
int c;
if (strrchr (argv[0], '/') != NULL)
program_name = strrchr (argv[0], '/') + 1;
else
program_name = argv[0];
while ((c = getopt_long (argc, argv, "ahp:svV", longopts, NULL)) != EOF)
switch (c)
{
case 'a': /* all */
++all;
break;
case 'h': /* help */
usage (stdout, 0);
break;
case 'p': /* priority */
priority = atoi(optarg);
break;
case 's': /* tell about current use of swap areas */
status = display_summary();
exit(status);
case 'v': /* be chatty */
++verbose;
break;
case 'V': /* version */
printf ("%s: %s\n", program_name, version);
exit (0);
case 0:
break;
case '?':
default:
usage (stderr, 1);
}
argv += optind;
status = 0;
if (all) {
FILE *fp = setmntent(_PATH_FSTAB, "r");
if (fp == NULL) {
fprintf(stderr, "%s: cannot open %s: %s\n", program_name,
_PATH_FSTAB, strerror(errno));
exit(2);
}
while ((fstab = getmntent(fp)) != NULL) {
if (streq (fstab->mnt_type, MNTTYPE_SWAP)) {
/* parse mount options; */
char *opt, *opts = strdup(fstab->mnt_opts);
for (opt = strtok (opts, ","); opt != NULL;
opt = strtok (NULL, ","))
if (strncmp(opt, "pri=", 4) == 0)
priority = atoi(opt+4);
status |= swap (fstab->mnt_fsname, priority);
}
}
} else if (*argv == NULL) {
usage (stderr, 2);
} else {
while (*argv != NULL)
status |= swap (*argv++,priority);
}
return status;
}
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