minix/commands/pax/cache.c
2006-01-20 14:45:27 +00:00

430 lines
9.5 KiB
C

/*-
* Copyright (c) 1992 Keith Muller.
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Keith Muller of the University of California, San Diego.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)cache.c 8.1 (Berkeley) 5/31/93";
#endif
#endif /* not lint */
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <stdio.h>
#include <pwd.h>
#include <grp.h>
#include <unistd.h>
#include <stdlib.h>
#include "pax.h"
#include "cache.h"
#include "extern.h"
/*
* routines that control user, group, uid and gid caches (for the archive
* member print routine).
* IMPORTANT:
* these routines cache BOTH hits and misses, a major performance improvement
*/
static int pwopn = 0; /* is password file open */
static int gropn = 0; /* is group file open */
static UIDC **uidtb = NULL; /* uid to name cache */
static GIDC **gidtb = NULL; /* gid to name cache */
static UIDC **usrtb = NULL; /* user name to uid cache */
static GIDC **grptb = NULL; /* group name to gid cache */
/*
* uidtb_start
* creates an an empty uidtb
* Return:
* 0 if ok, -1 otherwise
*/
int
uidtb_start(void)
{
static int fail = 0;
if (uidtb != NULL)
return(0);
if (fail)
return(-1);
if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
++fail;
paxwarn(1, "Unable to allocate memory for user id cache table");
return(-1);
}
return(0);
}
/*
* gidtb_start
* creates an an empty gidtb
* Return:
* 0 if ok, -1 otherwise
*/
int
gidtb_start(void)
{
static int fail = 0;
if (gidtb != NULL)
return(0);
if (fail)
return(-1);
if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
++fail;
paxwarn(1, "Unable to allocate memory for group id cache table");
return(-1);
}
return(0);
}
/*
* usrtb_start
* creates an an empty usrtb
* Return:
* 0 if ok, -1 otherwise
*/
int
usrtb_start(void)
{
static int fail = 0;
if (usrtb != NULL)
return(0);
if (fail)
return(-1);
if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
++fail;
paxwarn(1, "Unable to allocate memory for user name cache table");
return(-1);
}
return(0);
}
/*
* grptb_start
* creates an an empty grptb
* Return:
* 0 if ok, -1 otherwise
*/
int
grptb_start(void)
{
static int fail = 0;
if (grptb != NULL)
return(0);
if (fail)
return(-1);
if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
++fail;
paxwarn(1,"Unable to allocate memory for group name cache table");
return(-1);
}
return(0);
}
/*
* name_uid()
* caches the name (if any) for the uid. If frc set, we always return the
* the stored name (if valid or invalid match). We use a simple hash table.
* Return
* Pointer to stored name (or an empty string).
*/
const char *
name_uid(uid_t uid, int frc)
{
struct passwd *pw;
UIDC *ptr;
if ((uidtb == NULL) && (uidtb_start() < 0))
return("");
/*
* see if we have this uid cached
*/
ptr = uidtb[uid % UID_SZ];
if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
/*
* have an entry for this uid
*/
if (frc || (ptr->valid == VALID))
return(ptr->name);
return("");
}
/*
* No entry for this uid, we will add it
*/
if (!pwopn) {
setpassent(1);
++pwopn;
}
if (ptr == NULL)
ptr = uidtb[uid % UID_SZ] = (UIDC *)malloc(sizeof(UIDC));
if ((pw = getpwuid(uid)) == NULL) {
/*
* no match for this uid in the local password file
* a string that is the uid in numeric format
*/
if (ptr == NULL)
return("");
ptr->uid = uid;
ptr->valid = INVALID;
# ifdef NET2_STAT
(void)snprintf(ptr->name, sizeof(ptr->name), "%u", uid);
# else
(void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
(unsigned long)uid);
# endif
if (frc == 0)
return("");
} else {
/*
* there is an entry for this uid in the password file
*/
if (ptr == NULL)
return(pw->pw_name);
ptr->uid = uid;
(void)strncpy(ptr->name, pw->pw_name, UNMLEN - 1);
ptr->name[UNMLEN-1] = '\0';
ptr->valid = VALID;
}
return(ptr->name);
}
/*
* name_gid()
* caches the name (if any) for the gid. If frc set, we always return the
* the stored name (if valid or invalid match). We use a simple hash table.
* Return
* Pointer to stored name (or an empty string).
*/
const char *
name_gid(gid_t gid, int frc)
{
struct group *gr;
GIDC *ptr;
if ((gidtb == NULL) && (gidtb_start() < 0))
return("");
/*
* see if we have this gid cached
*/
ptr = gidtb[gid % GID_SZ];
if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
/*
* have an entry for this gid
*/
if (frc || (ptr->valid == VALID))
return(ptr->name);
return("");
}
/*
* No entry for this gid, we will add it
*/
if (!gropn) {
setgroupent(1);
++gropn;
}
if (ptr == NULL)
ptr = gidtb[gid % GID_SZ] = (GIDC *)malloc(sizeof(GIDC));
if ((gr = getgrgid(gid)) == NULL) {
/*
* no match for this gid in the local group file, put in
* a string that is the gid in numeric format
*/
if (ptr == NULL)
return("");
ptr->gid = gid;
ptr->valid = INVALID;
# ifdef NET2_STAT
(void)snprintf(ptr->name, sizeof(ptr->name), "%u", gid);
# else
(void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
(unsigned long)gid);
# endif
if (frc == 0)
return("");
} else {
/*
* there is an entry for this group in the group file
*/
if (ptr == NULL)
return(gr->gr_name);
ptr->gid = gid;
(void)strncpy(ptr->name, gr->gr_name, GNMLEN - 1);
ptr->name[GNMLEN-1] = '\0';
ptr->valid = VALID;
}
return(ptr->name);
}
/*
* uid_name()
* caches the uid for a given user name. We use a simple hash table.
* Return
* the uid (if any) for a user name, or a -1 if no match can be found
*/
int
uid_name(char *name, uid_t *uid)
{
struct passwd *pw;
UIDC *ptr;
int namelen;
/*
* return -1 for mangled names
*/
if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
return(-1);
if ((usrtb == NULL) && (usrtb_start() < 0))
return(-1);
/*
* look up in hash table, if found and valid return the uid,
* if found and invalid, return a -1
*/
ptr = usrtb[st_hash(name, namelen, UNM_SZ)];
if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
if (ptr->valid == INVALID)
return(-1);
*uid = ptr->uid;
return(0);
}
if (!pwopn) {
setpassent(1);
++pwopn;
}
if (ptr == NULL)
ptr = usrtb[st_hash(name, namelen, UNM_SZ)] =
(UIDC *)malloc(sizeof(UIDC));
/*
* no match, look it up, if no match store it as an invalid entry,
* or store the matching uid
*/
if (ptr == NULL) {
if ((pw = getpwnam(name)) == NULL)
return(-1);
*uid = pw->pw_uid;
return(0);
}
(void)strncpy(ptr->name, name, UNMLEN - 1);
ptr->name[UNMLEN-1] = '\0';
if ((pw = getpwnam(name)) == NULL) {
ptr->valid = INVALID;
return(-1);
}
ptr->valid = VALID;
*uid = ptr->uid = pw->pw_uid;
return(0);
}
/*
* gid_name()
* caches the gid for a given group name. We use a simple hash table.
* Return
* the gid (if any) for a group name, or a -1 if no match can be found
*/
int
gid_name(char *name, gid_t *gid)
{
struct group *gr;
GIDC *ptr;
int namelen;
/*
* return -1 for mangled names
*/
if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
return(-1);
if ((grptb == NULL) && (grptb_start() < 0))
return(-1);
/*
* look up in hash table, if found and valid return the uid,
* if found and invalid, return a -1
*/
ptr = grptb[st_hash(name, namelen, GID_SZ)];
if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
if (ptr->valid == INVALID)
return(-1);
*gid = ptr->gid;
return(0);
}
if (!gropn) {
setgroupent(1);
++gropn;
}
if (ptr == NULL)
ptr = grptb[st_hash(name, namelen, GID_SZ)] =
(GIDC *)malloc(sizeof(GIDC));
/*
* no match, look it up, if no match store it as an invalid entry,
* or store the matching gid
*/
if (ptr == NULL) {
if ((gr = getgrnam(name)) == NULL)
return(-1);
*gid = gr->gr_gid;
return(0);
}
(void)strncpy(ptr->name, name, GNMLEN - 1);
ptr->name[GNMLEN-1] = '\0';
if ((gr = getgrnam(name)) == NULL) {
ptr->valid = INVALID;
return(-1);
}
ptr->valid = VALID;
*gid = ptr->gid = gr->gr_gid;
return(0);
}