freebsd-skq/usr.sbin/pkg_install/lib/pen.c
2002-04-01 09:39:07 +00:00

177 lines
4.3 KiB
C

/*
* 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "lib.h"
#include <err.h>
#include <libgen.h>
#include <sys/signal.h>
#include <sys/param.h>
#include <sys/mount.h>
/* For keeping track of where we are */
static char PenLocation[FILENAME_MAX];
static char Previous[FILENAME_MAX];
char *
where_playpen(void)
{
return PenLocation;
}
/* Find a good place to play. */
static char *
find_play_pen(char *pen, off_t sz)
{
char *cp;
struct stat sb;
if (pen[0] && isdir(dirname(pen)) == TRUE && (min_free(dirname(pen)) >= sz))
return pen;
else if ((cp = getenv("PKG_TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz))
sprintf(pen, "%s/instmp.XXXXXX", cp);
else if ((cp = getenv("TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz))
sprintf(pen, "%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) == SUCCESS || mkdir("/usr/tmp", 01777) == SUCCESS) && min_free("/usr/tmp") >= sz)
strcpy(pen, "/usr/tmp/instmp.XXXXXX");
else {
cleanup(0);
errx(2, __FUNCTION__
": can't find enough temporary space to extract the files, please set your\n"
"PKG_TMPDIR environment variable to a location with at least %ld bytes\n"
"free", (long)sz);
return NULL;
}
return pen;
}
#define MAX_STACK 20
static char *pstack[MAX_STACK];
static int pdepth = -1;
static void
pushPen(const char *pen)
{
if (++pdepth == MAX_STACK)
errx(2, __FUNCTION__ ": stack overflow.\n");
pstack[pdepth] = strdup(pen);
}
static void
popPen(char *pen)
{
if (pdepth == -1) {
pen[0] = '\0';
return;
}
strcpy(pen, pstack[pdepth]);
free(pstack[pdepth--]);
}
/*
* Make a temporary directory to play in and chdir() to it, returning
* pathname of previous working directory.
*/
char *
make_playpen(char *pen, off_t sz)
{
if (!find_play_pen(pen, sz))
return NULL;
if (!mkdtemp(pen)) {
cleanup(0);
errx(2, __FUNCTION__ ": can't mktemp '%s'", pen);
}
if (chmod(pen, 0700) == FAIL) {
cleanup(0);
errx(2, __FUNCTION__ ": can't mkdir '%s'", pen);
}
if (Verbose) {
if (sz)
fprintf(stderr, "Requested space: %d bytes, free space: %qd bytes in %s\n", (int)sz, (long long)min_free(pen), pen);
}
if (min_free(pen) < sz) {
rmdir(pen);
cleanup(0);
errx(2, __FUNCTION__ ": 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 (!getcwd(Previous, FILENAME_MAX)) {
upchuck("getcwd");
return NULL;
}
if (chdir(pen) == FAIL) {
cleanup(0);
errx(2, __FUNCTION__ ": can't chdir to '%s'", pen);
}
if (PenLocation[0])
pushPen(PenLocation);
strcpy(PenLocation, pen);
return Previous;
}
/* Convenience routine for getting out of playpen */
void
leave_playpen()
{
void (*oldsig)(int);
/* Don't interrupt while we're cleaning up */
oldsig = signal(SIGINT, SIG_IGN);
if (Previous[0]) {
if (chdir(Previous) == FAIL) {
cleanup(0);
errx(2, __FUNCTION__ ": can't chdir back to '%s'", Previous);
}
Previous[0] = '\0';
}
if (PenLocation[0]) {
if (PenLocation[0] == '/' && vsystem("rm -rf %s", PenLocation))
warnx("couldn't remove temporary dir '%s'", PenLocation);
popPen(PenLocation);
}
signal(SIGINT, oldsig);
}
off_t
min_free(const 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;
}