1/* 2 * FreeBSD install - a package for the installation and maintenance 3 * of non-core utilities. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * Jordan K. Hubbard 15 * 18 July 1993 16 * 17 * Routines for managing the "play pen". 18 * 19 */ 20 21#include <sys/cdefs.h> 22__FBSDID("$FreeBSD: releng/10.2/usr.sbin/pkg_install/lib/pen.c 228990 2011-12-30 10:58:14Z uqs $"); 23 24#include "lib.h" 25#include <err.h> 26#include <libutil.h> 27#include <libgen.h> 28#include <sys/signal.h> 29#include <sys/param.h> 30#include <sys/mount.h> 31 32/* For keeping track of where we are */ 33static char PenLocation[FILENAME_MAX]; 34 35char * 36where_playpen(void) 37{ 38 return PenLocation; 39} 40 41/* Find a good place to play. */ 42static char * 43find_play_pen(char *pen, off_t sz) 44{ 45 char *cp; 46 struct stat sb; 47 char humbuf[6]; 48 49 if (pen[0] && isdir(dirname(pen)) == TRUE && (min_free(dirname(pen)) >= sz)) 50 return pen; 51 else if ((cp = getenv("PKG_TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz)) 52 sprintf(pen, "%s/instmp.XXXXXX", cp); 53 else if ((cp = getenv("TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz)) 54 sprintf(pen, "%s/instmp.XXXXXX", cp); 55 else if (stat("/var/tmp", &sb) != FAIL && min_free("/var/tmp") >= sz) 56 strcpy(pen, "/var/tmp/instmp.XXXXXX"); 57 else if (stat("/tmp", &sb) != FAIL && min_free("/tmp") >= sz) 58 strcpy(pen, "/tmp/instmp.XXXXXX"); 59 else if ((stat("/usr/tmp", &sb) == SUCCESS || mkdir("/usr/tmp", 01777) == SUCCESS) && min_free("/usr/tmp") >= sz) 60 strcpy(pen, "/usr/tmp/instmp.XXXXXX"); 61 else { 62 cleanup(0); 63 humanize_number(humbuf, sizeof humbuf, sz, "", HN_AUTOSCALE, 64 HN_NOSPACE); 65 errx(2, 66"%s: can't find enough temporary space to extract the files, please set your\n" 67"PKG_TMPDIR environment variable to a location with at least %s bytes\n" 68"free", __func__, humbuf); 69 return NULL; 70 } 71 return pen; 72} 73 74#define MAX_STACK 20 75static char *pstack[MAX_STACK]; 76static int pdepth = -1; 77 78static const char * 79pushPen(const char *pen) 80{ 81 if (++pdepth == MAX_STACK) 82 errx(2, "%s: stack overflow.\n", __func__); 83 pstack[pdepth] = strdup(pen); 84 85 return pstack[pdepth]; 86} 87 88static void 89popPen(char *pen) 90{ 91 if (pdepth == -1) { 92 pen[0] = '\0'; 93 return; 94 } 95 strcpy(pen, pstack[pdepth]); 96 free(pstack[pdepth--]); 97} 98 99/* 100 * Make a temporary directory to play in and chdir() to it, returning 101 * pathname of previous working directory. 102 */ 103const char * 104make_playpen(char *pen, off_t sz) 105{ 106 char humbuf1[6], humbuf2[6]; 107 char cwd[FILENAME_MAX]; 108 109 if (!find_play_pen(pen, sz)) 110 return NULL; 111 112 if (!mkdtemp(pen)) { 113 cleanup(0); 114 errx(2, "%s: can't mktemp '%s'", __func__, pen); 115 } 116 117 if (Verbose) { 118 if (sz) { 119 humanize_number(humbuf1, sizeof humbuf1, sz, "", HN_AUTOSCALE, 120 HN_NOSPACE); 121 humanize_number(humbuf2, sizeof humbuf2, min_free(pen), 122 "", HN_AUTOSCALE, HN_NOSPACE); 123 fprintf(stderr, "Requested space: %s bytes, free space: %s bytes in %s\n", humbuf1, humbuf2, pen); 124 } 125 } 126 127 if (min_free(pen) < sz) { 128 rmdir(pen); 129 cleanup(0); 130 errx(2, "%s: not enough free space to create '%s'.\n" 131 "Please set your PKG_TMPDIR environment variable to a location\n" 132 "with more space and\ntry the command again", __func__, pen); 133 } 134 135 if (!getcwd(cwd, FILENAME_MAX)) { 136 upchuck("getcwd"); 137 return NULL; 138 } 139 140 if (chdir(pen) == FAIL) { 141 cleanup(0); 142 errx(2, "%s: can't chdir to '%s'", __func__, pen); 143 } 144 145 strcpy(PenLocation, pen); 146 return pushPen(cwd); 147} 148 149/* Convenience routine for getting out of playpen */ 150int 151leave_playpen() 152{ 153 static char left[FILENAME_MAX]; 154 void (*oldsig)(int); 155 156 if (!PenLocation[0]) 157 return 0; 158 159 /* Don't interrupt while we're cleaning up */ 160 oldsig = signal(SIGINT, SIG_IGN); 161 strcpy(left, PenLocation); 162 popPen(PenLocation); 163 164 if (chdir(PenLocation) == FAIL) { 165 cleanup(0); 166 errx(2, "%s: can't chdir back to '%s'", __func__, PenLocation); 167 } 168 169 if (left[0] == '/' && vsystem("/bin/rm -rf %s", left)) 170 warnx("couldn't remove temporary dir '%s'", left); 171 signal(SIGINT, oldsig); 172 173 return 1; 174} 175 176off_t 177min_free(const char *tmpdir) 178{ 179 struct statfs buf; 180 181 if (statfs(tmpdir, &buf) != 0) { 182 warn("statfs"); 183 return -1; 184 } 185 return (off_t)buf.f_bavail * (off_t)buf.f_bsize; 186} 187