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/* $NetBSD: pen.c,v 1.17 2005/02/20 09:17:25 grant Exp $ */
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <nbcompat.h>
#if HAVE_SYS_CDEFS_H
#include <sys/cdefs.h>
#endif
#ifndef lint
#if 0
static const char *rcsid = "from FreeBSD Id: pen.c,v 1.25 1997/10/08 07:48:12 charnier Exp";
#else
__RCSID("$NetBSD: pen.c,v 1.17 2005/02/20 09:17:25 grant Exp $");
#endif
#endif
/*
* FreeBSD install - a package for the installation and maintainance
* of non-core utilities.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* Jordan K. Hubbard
* 18 July 1993
*
* Routines for managing the "play pen".
*
*/
#if HAVE_ERR_H
#include <err.h>
#endif
#include "lib.h"
#if HAVE_SYS_SIGNAL_H
#include <sys/signal.h>
#endif
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#if HAVE_SYS_MOUNT_H
#include <sys/mount.h>
#endif
#if HAVE_SYS_VFS_H
#include <sys/vfs.h>
#endif
#if HAVE_SYS_STATVFS_H
#include <sys/statvfs.h>
#endif
/* For keeping track of where we are */
static char Current[MaxPathSize];
static char Previous[MaxPathSize];
static int CurrentSet; /* rm -fr Current only if it's really set! */
/* CurrentSet is set to 0 before strcpy()s
* to prevent rm'ing of a partial string
* when interrupted by ^C */
#if 0
/*
* Backup Current and Previous into temp. strings that are later
* restored & freed by restore_dirs
* This is to make nested calls to make_playpen/leave_playpen work
*/
void
save_dirs(char **c, char **p)
{
*c = strdup(Current); /* XXX */
*p = strdup(Previous);
}
/*
* Restore Current and Previous from temp strings that were created
* by safe_dirs.
* This is to make nested calls to make_playpen/leave_playpen work
*/
void
restore_dirs(char *c, char *p)
{
CurrentSet = 0; /* prevent from deleting */
strlcpy(Current, c, sizeof(Current));
CurrentSet = 1; /* rm -fr Current is safe now */
free(c);
strlcpy(Previous, p, sizeof(Previous));
free(p);
}
#endif
char *
where_playpen(void)
{
return Current;
}
/*
* Find a good place to play.
*/
static char *
find_play_pen(char *pen, size_t pensize, size_t sz)
{
char *cp;
struct stat sb;
if (pen && pen[0] && stat(pen, &sb) != FAIL && (min_free(pen) >= sz))
return pen;
else if ((cp = getenv("PKG_TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz))
(void) snprintf(pen, pensize, "%s/instmp.XXXXXX", cp);
else if ((cp = getenv("TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz))
(void) snprintf(pen, pensize, "%s/instmp.XXXXXX", cp);
else if (stat("/var/tmp", &sb) != FAIL && min_free("/var/tmp") >= sz)
strlcpy(pen, "/var/tmp/instmp.XXXXXX", pensize);
else if (stat("/tmp", &sb) != FAIL && min_free("/tmp") >= sz)
strlcpy(pen, "/tmp/instmp.XXXXXX", pensize);
else if (stat("/usr/tmp", &sb) != FAIL && min_free("/usr/tmp") >= sz)
strlcpy(pen, "/usr/tmp/instmp.XXXXXX", pensize);
else {
cleanup(0);
errx(2,
"can't find enough temporary space to extract the files, please set your\n"
"PKG_TMPDIR environment variable to a location with at least %lu bytes\n"
"free", (u_long) sz);
return NULL;
}
return pen;
}
/*
* Make a temporary directory to play in and chdir() to it, returning
* pathname of previous working directory.
*/
char *
make_playpen(char *pen, size_t pensize, size_t sz)
{
if (!find_play_pen(pen, pensize, sz))
return NULL;
if (!mkdtemp(pen)) {
cleanup(0);
errx(2, "can't mkdtemp '%s'", pen);
}
if (Verbose) {
if (sz)
fprintf(stderr,
"Requested space: %lu bytes, free space: %lld bytes in %s\n",
(u_long) sz, (long long) min_free(pen), pen);
}
if (min_free(pen) < sz) {
rmdir(pen);
cleanup(0);
errx(2, "not enough free space to create '%s'.\n"
"Please set your PKG_TMPDIR environment variable to a location\n"
"with more space and\ntry the command again", pen);
}
if (Current[0])
strlcpy(Previous, Current, sizeof(Previous));
else if (!getcwd(Previous, MaxPathSize)) {
cleanup(0);
err(EXIT_FAILURE, "fatal error during execution: getcwd");
}
if (chdir(pen) == FAIL) {
cleanup(0);
errx(2, "can't chdir to '%s'", pen);
}
CurrentSet = 0; strlcpy(Current, pen, sizeof(Current)); CurrentSet = 1;
return Previous;
}
/*
* Convenience routine for getting out of playpen
*/
void
leave_playpen(char *save)
{
void (*oldsig) (int);
/* Make us interruptable while we're cleaning up - just in case... */
oldsig = signal(SIGINT, SIG_DFL);
if (Previous[0] && chdir(Previous) == FAIL) {
cleanup(0);
errx(2, "can't chdir back to '%s'", Previous);
} else if (CurrentSet && Current[0] && strcmp(Current, Previous)) {
if (strcmp(Current, "/") == 0) {
fprintf(stderr, "PANIC: About to rm -fr / (not doing so, aborting)\n");
abort();
}
if (fexec("rm", "-fr", Current, NULL))
warnx("couldn't remove temporary dir '%s'", Current);
strlcpy(Current, Previous, sizeof(Current));
}
if (save)
strlcpy(Previous, save, sizeof(Previous));
else
Previous[0] = '\0';
signal(SIGINT, oldsig);
}
/*
* Return free disk space (in bytes) on given file system.
* Returns size in a uint64_t since off_t isn't 64 bits on all
* operating systems.
*/
uint64_t
min_free(char *tmpdir)
{
struct statvfs buf;
if (statvfs(tmpdir, &buf) != 0) {
warn("statvfs");
return 0;
}
return (uint64_t)buf.f_bavail * buf.f_bsize;
}
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