NetBSD/usr.sbin/pkg_install/lib/pen.c

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/* $NetBSD: pen.c,v 1.18 2000/11/26 03:12:01 hubertf Exp $ */
1997-10-17 18:53:18 +04:00
#include <sys/cdefs.h>
#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 1.18 2000/11/26 03:12:01 hubertf 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".
*
*/
#include <err.h>
#include "lib.h"
#include <sys/signal.h>
#include <sys/param.h>
#include <sys/mount.h>
/* For keeping track of where we are */
static char Current[FILENAME_MAX];
static char Previous[FILENAME_MAX];
static int CurrentSet; /* rm -rf 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 */
/*
* Backup Current and Previous into temp. strings that are later
* restored & freed by restore_dirs
* This is to make nested calls to makeplaypen/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 makeplaypen/leave_playpen work
*/
void
restore_dirs(char *c, char *p)
{
CurrentSet = 0; /* prevent from deleting */
strcpy(Current, c);
CurrentSet = 1; /* rm -fr Current is safe now */
free(c);
strcpy(Previous, p);
free(p);
}
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)
strcpy(pen, "/var/tmp/instmp.XXXXXX");
else if (stat("/tmp", &sb) != FAIL && min_free("/tmp") >= sz)
strcpy(pen, "/tmp/instmp.XXXXXX");
else if (stat("/usr/tmp", &sb) != FAIL && min_free("/usr/tmp") >= sz)
strcpy(pen, "/usr/tmp/instmp.XXXXXX");
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;
1999-03-02 06:04:06 +03:00
#if (defined(NetBSD1_3) || (NetBSD <= 199713)) && (NetBSD1_3 <9)
/* values from 1.3.2/1.3I */
/* mkdtemp(3) is not present on 1.3.3 and below */
if (!mktemp(pen)) {
cleanup(0);
errx(2, "can't mktemp '%s'", pen);
}
if (mkdir(pen, 0755) == FAIL) {
cleanup(0);
errx(2, "can't mkdir '%s'", pen);
}
1999-01-19 20:01:56 +03:00
#else
if (!mkdtemp(pen)) {
cleanup(0);
errx(2, "can't mkdtemp '%s'", pen);
}
1999-01-19 20:01:56 +03:00
#endif
if (Verbose) {
if (sz)
fprintf(stderr, "Requested space: %lu bytes, free space: %qd 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])
strcpy(Previous, Current);
else if (!getcwd(Previous, FILENAME_MAX)) {
cleanup(0);
err(1, "fatal error during execution: getcwd");
}
if (chdir(pen) == FAIL) {
cleanup(0);
errx(2, "can't chdir to '%s'", pen);
}
strcpy(Current, pen); 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 -rf / (not doing so, aborting)\n");
abort();
}
if (vsystem("rm -rf %s", Current))
warnx("couldn't remove temporary dir '%s'", Current);
strcpy(Current, Previous);
}
if (save)
strcpy(Previous, save);
else
Previous[0] = '\0';
signal(SIGINT, oldsig);
}
/*
* Return free disk space (in bytes) on given file system
*/
off_t
min_free(char *tmpdir)
{
struct statfs buf;
if (statfs(tmpdir, &buf) != 0) {
warn("statfs");
return -1;
}
return (off_t) buf.f_bavail * (off_t) buf.f_bsize;
}