From 8500b0cabadf7500bdccdf6b94ad3f36bf7a96c9 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sat, 14 Aug 2004 04:21:09 +0000 Subject: Update. * nis/nss_nis/nis-netgrp.c: Remove locking by using data in struct __netgrent object passed in instead of global variables. Optimize. * nis/nss_nisplus/nisplus-netgrp.c: Remove locking by using data in struct __netgrent object passed in instead of global variables. * inet/netgroup.h (struct __netgrent): Add service_user field. Move cursor in anonymous union, add new field location to that union. * inet/getnetgrent_r.c: Extensive rewrite to really enable concurrent uset of set/get/endnetgrent and innetgr. --- inet/getnetgrent_r.c | 96 ++++++++++++++++++++-------------------------------- 1 file changed, 36 insertions(+), 60 deletions(-) (limited to 'inet/getnetgrent_r.c') diff --git a/inet/getnetgrent_r.c b/inet/getnetgrent_r.c index 8785398..640210a 100644 --- a/inet/getnetgrent_r.c +++ b/inet/getnetgrent_r.c @@ -28,10 +28,6 @@ /* Protect above variable against multiple uses at the same time. */ __libc_lock_define_initialized (static, lock) -/* This handle for the NSS data base is shared between all - set/get/endXXXent functions. */ -static service_user *nip; - /* The whole information for the set/get/endnetgrent functions are kept in this structure. */ static struct __netgrent dataset; @@ -45,7 +41,7 @@ extern int __nss_netgroup_lookup (service_user **nip, const char *name, current location if it's not nil. Return nonzero if there are no services (left). */ static enum nss_status -setup (void **fctp, const char *func_name, int all) +setup (void **fctp, const char *func_name, int all, service_user **nipp) { /* Remember the first service_entry, it's always the same. */ static service_user *startp; @@ -53,19 +49,21 @@ setup (void **fctp, const char *func_name, int all) if (startp == NULL) { - no_more = __nss_netgroup_lookup (&nip, func_name, fctp); - startp = no_more ? (service_user *) -1 : nip; + /* Executing this more than once at the same time must yield the + same result every time. So we need no locking. */ + no_more = __nss_netgroup_lookup (nipp, func_name, fctp); + startp = no_more ? (service_user *) -1 : *nipp; } else if (startp == (service_user *) -1) /* No services at all. */ return 1; else { - if (all || !nip) + if (all || *nipp == NULL) /* Reset to the beginning of the service list. */ - nip = startp; + *nipp = startp; /* Look up the first function. */ - no_more = __nss_lookup (&nip, func_name, fctp); + no_more = __nss_lookup (nipp, func_name, fctp); } return no_more; } @@ -101,16 +99,15 @@ __internal_setnetgrent_reuse (const char *group, struct __netgrent *datap, } fct; enum nss_status status = NSS_STATUS_UNAVAIL; struct name_list *new_elem; - int no_more; /* Cycle through all the services and run their setnetgrent functions. */ - no_more = setup (&fct.ptr, "setnetgrent", 1); + int no_more = setup (&fct.ptr, "setnetgrent", 1, &datap->nip); while (! no_more) { /* Ignore status, we force check in `__nss_next'. */ status = (*fct.f) (group, datap); - no_more = __nss_next (&nip, "setnetgrent", &fct.ptr, status, 0); + no_more = __nss_next (&datap->nip, "setnetgrent", &fct.ptr, status, 0); } /* Add the current group to the list of known groups. */ @@ -173,20 +170,19 @@ internal_endnetgrent (struct __netgrent *datap) enum nss_status (*f) (struct __netgrent *); void *ptr; } fct; - int no_more; /* Remember which was the last used service. */ - old_nip = nip; + old_nip = datap->nip; /* Cycle through all the services and run their endnetgrent functions. */ - no_more = setup (&fct.ptr, "endnetgrent", 1); + int no_more = setup (&fct.ptr, "endnetgrent", 1, &datap->nip); while (! no_more) { /* Ignore status, we force check in `__nss_next'. */ (void) (*fct.f) (datap); - no_more = (nip == old_nip - || __nss_next (&nip, "endnetgrent", &fct.ptr, 0, 1)); + no_more = (datap->nip == old_nip + || __nss_next (&datap->nip, "endnetgrent", &fct.ptr, 0, 1)); } /* Now free list of all netgroup names from last run. */ @@ -222,7 +218,6 @@ internal_getnetgrent_r (char **hostp, char **userp, char **domainp, enum nss_status (*f) (struct __netgrent *, char *, size_t, int *); void *ptr; } fct; - int no_more; /* Initialize status to return if no more functions are found. */ enum nss_status status = NSS_STATUS_NOTFOUND; @@ -230,7 +225,7 @@ internal_getnetgrent_r (char **hostp, char **userp, char **domainp, /* Run through available functions, starting with the same function last run. We will repeat each function as long as it succeeds, and then go on to the next service action. */ - no_more = setup (&fct.ptr, "getnetgrent_r", 0); + int no_more = setup (&fct.ptr, "getnetgrent_r", 0, &datap->nip); while (! no_more) { status = (*fct.f) (datap, buffer, buflen, &errno); @@ -284,7 +279,7 @@ internal_getnetgrent_r (char **hostp, char **userp, char **domainp, } } - no_more = __nss_next (&nip, "getnetgrent_r", &fct.ptr, status, 0); + no_more = __nss_next (&datap->nip, "getnetgrent_r", &fct.ptr, status, 0); } if (status == NSS_STATUS_SUCCESS) @@ -337,14 +332,12 @@ innetgr (const char *netgroup, const char *host, const char *user, int (*f) (struct __netgrent *, char *, size_t, int *); void *ptr; } getfct; - struct name_list *known = NULL; - struct name_list *needed = NULL; + struct __netgrent entry; int result = 0; - int no_more; const char *current_group = netgroup; int real_entry = 0; - __libc_lock_lock (lock); + memset (&entry, '\0', sizeof (entry)); /* Walk through the services until we found an answer or we shall not work further. We can do some optimization here. Since all @@ -352,19 +345,14 @@ innetgr (const char *netgroup, const char *host, const char *user, the work during one walk through the service list. */ while (1) { - no_more = setup (&setfct.ptr, "setnetgrent", 1); + int no_more = setup (&setfct.ptr, "setnetgrent", 1, &entry.nip); while (! no_more) { - enum nss_status status; - struct __netgrent entry; - - /* Clear the space for the netgroup data. */ - __bzero (&entry, sizeof (entry)); - /* Open netgroup. */ - status = (*setfct.f) (current_group, &entry); + enum nss_status status = (*setfct.f) (current_group, &entry); + if (status == NSS_STATUS_SUCCESS - && __nss_lookup (&nip, "getnetgrent_r", &getfct.ptr) == 0) + && __nss_lookup (&entry.nip, "getnetgrent_r", &getfct.ptr) == 0) { char buffer[1024]; @@ -376,7 +364,8 @@ innetgr (const char *netgroup, const char *host, const char *user, /* Make sure we haven't seen the name before. */ struct name_list *namep; - for (namep = known; namep != NULL; namep = namep->next) + for (namep = entry.known_groups; namep != NULL; + namep = namep->next) if (strcmp (entry.val.group, namep->name) == 0) break; if (namep == NULL @@ -393,9 +382,9 @@ innetgr (const char *netgroup, const char *host, const char *user, break; } - namep->next = needed; + namep->next = entry.needed_groups; memcpy (namep->name, entry.val.group, group_len); - needed = namep; + entry.needed_groups = namep; } } else @@ -425,21 +414,21 @@ innetgr (const char *netgroup, const char *host, const char *user, } /* Free all resources of the service. */ - if (__nss_lookup (&nip, "endnetgrent", &endfct.ptr) == 0) + if (__nss_lookup (&entry.nip, "endnetgrent", &endfct.ptr) == 0) (*endfct.f) (&entry); /* Look for the next service. */ - no_more = __nss_next (&nip, "setnetgrent", + no_more = __nss_next (&entry.nip, "setnetgrent", &setfct.ptr, status, 0); } - if (result == 0 && needed != NULL) + if (result == 0 && entry.needed_groups != NULL) { - struct name_list *tmp = needed; - needed = tmp->next; - tmp->next = known; - known = tmp; - current_group = known->name; + struct name_list *tmp = entry.needed_groups; + entry.needed_groups = tmp->next; + tmp->next = entry.known_groups; + entry.known_groups = tmp; + current_group = entry.known_groups->name; continue; } @@ -447,22 +436,9 @@ innetgr (const char *netgroup, const char *host, const char *user, break; } - __libc_lock_unlock (lock); - /* Free the memory. */ - while (known != NULL) - { - struct name_list *tmp = known; - known = known->next; - free (tmp); - } - while (needed != NULL) - { - struct name_list *tmp = needed; - needed = needed->next; - free (tmp); - } + free_memory (&entry); - return result == 1; + return result; } libc_hidden_def (innetgr) -- cgit v1.1