netconfig is not threadsafe
Steven Haber
shaber at isilon.com
Fri Aug 24 22:18:24 UTC 2012
Yeah, I definitely think it should support threading. It looks like we
only use netconfig a few places: RPC, and some sbin services like
mountd, yp, and keyserv. So we could just serialize correctly in
RPC/mountd/etc., but I think it's better to protect the whole thing.
Linux (Ubuntu) has a FreeBSD man page for netconfig with no mention of
_r routines; the APIs look pretty much like they do on FreeBSD. I can't
seem to find the source in my libc, however. For netgrent (similar to
netconfig) there is getnetgrent_r(), a GNU-specific call, which just
stores retrieved strings in a buffer you pass in, but near as I can tell
the calls aren't actually thread safe:
http://sourceware.org/git/?p=glibc.git;a=blob;f=inet/getnetgrent_r.c;h=8e69ec7b1135dc886a1cf0730001fd709a701b87;hb=HEAD
All the data is just stored in a static, and calls to
set/get/endnetgrent are serialized by a lock, but you could call them
out of order with multiple threads.
In Solaris 10, you get a handle back from setnetconfig() that is unique
to your session. This implementation sounds fully threadsafe. Haven't
tried it.
On OSX 10.7.2 the calls look the same as FreeBSD (no handle) and it does
not mention whether or not it is threadsafe, though in BUGS it mentions:
"The function getnetgrent() returns pointers to dynamically allocated
data areas that are freed when the function endnetgrent() is called."
I haven't tried threading it on OSX, either.
I'm pasting a better version of the patch since Outlook destroyed my
last one.
Steven
From f3639afbe7993f3c699f23f4d77749ea01e8e8c8 Mon Sep 17 00:00:00 2001
From: Steven Haber <shaber at isilon.com>
Date: Thu, 23 Aug 2012 17:45:51 -0700
Subject: [PATCH] Fix for bug 95757. Make netconfig threadsafe so we can make
lots of RPC clients concurrently. The original locking had
no effect; there is no point in protecting the static
members since you should never have two threads in the same
get/set/endnetconfig. The point of these functions is to be
called in sequence as a transaction. You can't have
multiple threads calling them if the state is stored as a
process global. This fix moves the static vars to thread-
specific storage so that each thread can have its own
transaction, and removes the existing locking.
---
src/lib/libc/rpc/getnetconfig.c | 74
+++++++++++----------------------------
1 file changed, 21 insertions(+), 53 deletions(-)
diff --git a/src/lib/libc/rpc/getnetconfig.c
b/src/lib/libc/rpc/getnetconfig.c
index 0f7168f..2957d14 100644
--- a/src/lib/libc/rpc/getnetconfig.c
+++ b/src/lib/libc/rpc/getnetconfig.c
@@ -119,22 +119,21 @@ struct netconfig_vars {
struct netconfig_list *nc_configs; /* pointer to the current
netconfig entry */
};
+struct nc_thread_vars {
+ int nc_error;
+ FILE *nc_file;
+ struct netconfig_info nc_ni;
+};
+
#define NC_VALID 0xfeed
#define NC_STORAGE 0xf00d
#define NC_INVALID 0
-static int *__nc_error(void);
static int parse_ncp(char *, struct netconfig *);
static struct netconfig *dup_ncp(struct netconfig *);
-static FILE *nc_file; /* for netconfig db */
-static mutex_t nc_file_lock = MUTEX_INITIALIZER;
-
-static struct netconfig_info ni = { 0, 0, NULL, NULL};
-static mutex_t ni_lock = MUTEX_INITIALIZER;
-
static thread_key_t nc_key;
static once_t nc_once = ONCE_INITIALIZER;
static int nc_key_error;
@@ -148,34 +147,37 @@ nc_key_init(void)
#define MAXNETCONFIGLINE 1000
-static int *
-__nc_error()
+static struct nc_thread_vars *
+__nc_thread()
{
- static int nc_error = 0;
- int *nc_addr;
+ static struct nc_thread_vars nc_vars = {0, NULL, {0, 0, NULL, NULL}};
+ struct nc_thread_vars *nc_addr;
/*
- * Use the static `nc_error' if we are the main thread
+ * Use the static `nc_vars' if we are the main thread
* (including non-threaded programs), or if an allocation
* fails.
*/
if (thr_main())
- return (&nc_error);
+ return (&nc_vars);
if (thr_once(&nc_once, nc_key_init) != 0 || nc_key_error != 0)
- return (&nc_error);
- if ((nc_addr = (int *)thr_getspecific(nc_key)) == NULL) {
- nc_addr = (int *)malloc(sizeof (int));
+ return (&nc_vars);
+ if ((nc_addr = (struct nc_thread_vars *)thr_getspecific(nc_key))
+ == NULL) {
+ nc_addr = (struct nc_thread_vars *)
+ calloc(1, sizeof(struct nc_thread_vars));
if (thr_setspecific(nc_key, (void *) nc_addr) != 0) {
if (nc_addr)
free(nc_addr);
- return (&nc_error);
+ return (&nc_vars);
}
- *nc_addr = 0;
}
return (nc_addr);
}
-#define nc_error (*(__nc_error()))
+#define nc_error (*(&(__nc_thread()->nc_error)))
+#define nc_file (*(&(__nc_thread()->nc_file)))
+#define ni (*(&(__nc_thread()->nc_ni)))
/*
* A call to setnetconfig() establishes a /etc/netconfig "session". A
session
* "handle" is returned on a successful call. At the start of a
session (after
@@ -209,23 +211,14 @@ setnetconfig()
* For multiple calls, i.e. nc_file is not NULL, we just return the
* handle without reopening the netconfig db.
*/
- mutex_lock(&ni_lock);
ni.ref++;
- mutex_unlock(&ni_lock);
-
- mutex_lock(&nc_file_lock);
if ((nc_file != NULL) || (nc_file = fopen(NETCONFIG, "r")) != NULL) {
nc_vars->valid = NC_VALID;
nc_vars->flag = 0;
nc_vars->nc_configs = ni.head;
- mutex_unlock(&nc_file_lock);
return ((void *)nc_vars);
}
- mutex_unlock(&nc_file_lock);
-
- mutex_lock(&ni_lock);
ni.ref--;
- mutex_unlock(&ni_lock);
nc_error = NC_NONETCONFIG;
free(nc_vars);
@@ -254,13 +247,10 @@ void *handlep;
/*
* Verify that handle is valid
*/
- mutex_lock(&nc_file_lock);
if (ncp == NULL || nc_file == NULL) {
nc_error = NC_NOTINIT;
- mutex_unlock(&nc_file_lock);
return (NULL);
}
- mutex_unlock(&nc_file_lock);
switch (ncp->valid) {
case NC_VALID:
@@ -274,9 +264,7 @@ void *handlep;
*/
if (ncp->flag == 0) { /* first time */
ncp->flag = 1;
- mutex_lock(&ni_lock);
ncp->nc_configs = ni.head;
- mutex_unlock(&ni_lock);
if (ncp->nc_configs != NULL) /* entry already exist */
return(ncp->nc_configs->ncp);
}
@@ -289,12 +277,9 @@ void *handlep;
* If we cannot find the entry in the list and is end of file,
* we give up.
*/
- mutex_lock(&ni_lock);
if (ni.eof == 1) {
- mutex_unlock(&ni_lock);
return(NULL);
}
- mutex_unlock(&ni_lock);
break;
default:
@@ -316,18 +301,13 @@ void *handlep;
/*
* Read a line from netconfig file.
*/
- mutex_lock(&nc_file_lock);
do {
if (fgets(stringp, MAXNETCONFIGLINE, nc_file) == NULL) {
free(stringp);
- mutex_lock(&ni_lock);
ni.eof = 1;
- mutex_unlock(&ni_lock);
- mutex_unlock(&nc_file_lock);
return (NULL);
}
} while (*stringp == '#');
- mutex_unlock(&nc_file_lock);
list = (struct netconfig_list *) malloc(sizeof (struct
netconfig_list));
if (list == NULL) {
@@ -357,7 +337,6 @@ void *handlep;
* Reposition the current pointer of the handle to the last entry
* in the list.
*/
- mutex_lock(&ni_lock);
if (ni.head == NULL) { /* first entry */
ni.head = ni.tail = list;
}
@@ -367,7 +346,6 @@ void *handlep;
}
ncp->nc_configs = ni.tail;
result = ni.tail->ncp;
- mutex_unlock(&ni_lock);
return(result);
}
}
@@ -402,9 +380,7 @@ void *handlep;
nc_handlep->valid = NC_INVALID;
nc_handlep->flag = 0;
nc_handlep->nc_configs = NULL;
- mutex_lock(&ni_lock);
if (--ni.ref > 0) {
- mutex_unlock(&ni_lock);
free(nc_handlep);
return(0);
}
@@ -417,7 +393,6 @@ void *handlep;
ni.eof = ni.ref = 0;
ni.head = NULL;
ni.tail = NULL;
- mutex_unlock(&ni_lock);
while (q != NULL) {
p = q->next;
@@ -429,10 +404,8 @@ void *handlep;
}
free(nc_handlep);
- mutex_lock(&nc_file_lock);
fclose(nc_file);
nc_file = NULL;
- mutex_unlock(&nc_file_lock);
return (0);
}
@@ -481,21 +454,16 @@ getnetconfigent(netid)
* If all the netconfig db has been read and placed into the list and
* there is no match for the netid, return NULL.
*/
- mutex_lock(&ni_lock);
if (ni.head != NULL) {
for (list = ni.head; list; list = list->next) {
if (strcmp(list->ncp->nc_netid, netid) == 0) {
- mutex_unlock(&ni_lock);
return(dup_ncp(list->ncp));
}
}
if (ni.eof == 1) { /* that's all the entries */
- mutex_unlock(&ni_lock);
return(NULL);
}
}
- mutex_unlock(&ni_lock);
-
if ((file = fopen(NETCONFIG, "r")) == NULL) {
nc_error = NC_NONETCONFIG;
--
1.7.9.5
On 08/24/2012 01:17 PM, Alfred Perlstein wrote:
> I did a bit of research and this manual page:
> http://www.unix.com/man-page/All/3n/setnetconfig/
>
> seems to indicate that this is the best that is "expected"
> for thread safety:
>
> MULTITHREAD USAGE
> Thread Safe: Yes
> Cancel Safe: Yes
> Fork Safe: No
> Async-cancel Safe: No
> Async-signal Safe: No
>
> These functions can be called safely in a multithreaded environment.
> They may be cancellation points in that they call functions that are
> cancel points.
>
> In a multithreaded environment, these functions are not safe to be
> called by a child process after and before These functions should not
> be called by a multithreaded application that supports asynchronous
> cancellation or asynchronous signals.
>
> So this is awesome. Thank you.
>
> -Alfred
>
> * Alfred Perlstein <alfred at freebsd.org> [120824 13:14] wrote:
>> I suppose it can be fixed like this and the idea is pretty sound,
>> however I was wondering if you can you look at how Linux/Solaris/OSX
>> handle this?
>>
>> I would think there would be some form of "_r" routines that they
>> would use instead. Or maybe thier libc avoids calling these routines
>> somehow?
>>
>> That said this is good work and should go in barring other
>> implementations that may make more sense.
>>
>> -Alfred
>>
>> * Steven Haber <steven.haber at isilon.com> [120824 13:00] wrote:
>>> netconfig (libc routines for reading the netconfig file) is currently
>>> not threadsafe. It is a transactional API set, that is, you call
>>> setnetconfig() to open the file, read from the file with getnetconfig(),
>>> and close/cleanup with endnetconfig(). The problem is that the order
>>> that these routines are called in is important, but the state of the
>>> current transaction is stored in a per-process static, so only a single
>>> thread can do a transaction at one time. A patch from five years ago
>>> attempted to fix this:
>>>
>>>
>>>
>>> http://lists.freebsd.org/mailman/confirm/freebsd-threads/292f06b38808587
>>> 41c9034fb4173a14740c63a9e
>>>
>>>
>>>
>>> This patch does not solve the problem. It adds protection for the
>>> statics so that concurrent calls into set/get/endnetgrent() don't trash
>>> the statics. However, there is no use case where you would want two
>>> threads accessing any of these statics concurrently. To solve this
>>> problem, I have stored the FILE and netconfig_info statics on a
>>> per-thread basis using the pthreads key setup that was already in place
>>> for the error code. Now threads have their own set of stored state data,
>>> so no statics are necessary. I removed the original locking that had no
>>> effect.
>>>
>>>
>>>
>>> My repro is to spawn 32 threads that all create an RPC client
>>> simultaneously using libc's clnt_create(), which calls into netconfig.
>>> After patching, I no longer see the issue. Here is the stack when a
>>> thread collision occurs (same as in the original bug from 2007):
>>>
>>>
>>>
>>> #0 fclose (fp=0x0) at
>>> /root/Source/onefs/git/src/lib/libc/stdio/fclose.c:52
>>>
>>> #1 0x0000000802c83a79 in endnetconfig (handlep=0x80b1030a0) at
>>> /root/Source/onefs/git/src/lib/libc/rpc/getnetconfig.c:433
>>>
>>> #2 0x0000000802c811d0 in __rpc_endconf (vhandle=0x80b103090) at
>>> /root/Source/onefs/git/src/lib/libc/rpc/rpc_generic.c:445
>>>
>>> #3 0x0000000802c7331a in clnt_create_timed (hostname=0x804d7cd9b
>>> "tgroup %s", prog=134420864, vers=1, netclass=Variable "netclass" is not
>>> available.
>>>
>>> ) at /root/Source/onefs/git/src/lib/libc/rpc/clnt_generic.c:271
>>>
>>>
>>>
>>> This issue is present in FreeBSD head, though I'm reproducing on 7.1.
>>>
>>>
>>>
>>> Does the patch make sense? Should I open a bug on this somehow? I'm
>>> relatively new to contributing to FreeBSD.
>>>
>>>
>>>
>>> Thanks,
>>>
>>> Steven
>>>
>>>
>>>
>>>
>>>
>>> >From f3639afbe7993f3c699f23f4d77749ea01e8e8c8 Mon Sep 17 00:00:00 2001
>>>
>>> From: Steven Haber <shaber at isilon.com>
>>>
>>> Date: Thu, 23 Aug 2012 17:45:51 -0700
>>>
>>> Subject: [PATCH] Fix for bug 95757. Make netconfig threadsafe so we can
>>> make
>>>
>>> lots of RPC clients concurrently. The original locking had
>>>
>>> no effect; there is no point in protecting the static
>>>
>>> members since you should never have two threads in the same
>>>
>>> get/set/endnetconfig. The point of these functions is to be
>>>
>>> called in sequence as a transaction. You can't have
>>>
>>> multiple threads calling them if the state is stored as a
>>>
>>> process global. This fix moves the static vars to thread-
>>>
>>> specific storage so that each thread can have its own
>>>
>>> transaction, and removes the exiting locking.
>>>
>>> ---
>>>
>>> src/lib/libc/rpc/getnetconfig.c | 74
>>> +++++++++++----------------------------
>>>
>>> 1 file changed, 21 insertions(+), 53 deletions(-)
>>>
>>>
>>>
>>> diff --git a/src/lib/libc/rpc/getnetconfig.c
>>> b/src/lib/libc/rpc/getnetconfig.c
>>>
>>> index 0f7168f..2957d14 100644
>>>
>>> --- a/src/lib/libc/rpc/getnetconfig.c
>>>
>>> +++ b/src/lib/libc/rpc/getnetconfig.c
>>>
>>> @@ -119,22 +119,21 @@ struct netconfig_vars {
>>>
>>> struct netconfig_list *nc_configs; /* pointer to the current
>>> netconfig entry */
>>>
>>> };
>>>
>>> +struct nc_thread_vars {
>>>
>>> + int nc_error;
>>>
>>> + FILE *nc_file;
>>>
>>> + struct netconfig_info nc_ni;
>>>
>>> +};
>>>
>>> +
>>>
>>> #define NC_VALID 0xfeed
>>>
>>> #define NC_STORAGE 0xf00d
>>>
>>> #define NC_INVALID 0
>>>
>>>
>>>
>>> -static int *__nc_error(void);
>>>
>>> static int parse_ncp(char *, struct netconfig *);
>>>
>>> static struct netconfig *dup_ncp(struct netconfig *);
>>>
>>>
>>>
>>> -static FILE *nc_file; /* for netconfig db */
>>>
>>> -static mutex_t nc_file_lock = MUTEX_INITIALIZER;
>>>
>>> -
>>>
>>> -static struct netconfig_info ni = { 0, 0, NULL, NULL};
>>>
>>> -static mutex_t ni_lock = MUTEX_INITIALIZER;
>>>
>>> -
>>>
>>> static thread_key_t nc_key;
>>>
>>> static once_t nc_once = ONCE_INITIALIZER;
>>>
>>> static int nc_key_error;
>>>
>>> @@ -148,34 +147,37 @@ nc_key_init(void)
>>>
>>> #define MAXNETCONFIGLINE 1000
>>>
>>> -static int *
>>>
>>> -__nc_error()
>>>
>>> +static struct nc_thread_vars *
>>>
>>> +__nc_thread()
>>>
>>> {
>>>
>>> - static int nc_error = 0;
>>>
>>> - int *nc_addr;
>>>
>>> + static struct nc_thread_vars nc_vars = {0, NULL, {0, 0,
>>> NULL, NULL}};
>>>
>>> + struct nc_thread_vars *nc_addr;
>>>
>>> /*
>>>
>>> - * Use the static `nc_error' if we are the main thread
>>>
>>> + * Use the static `nc_vars' if we are the main thread
>>>
>>> * (including non-threaded programs), or if an allocation
>>>
>>> * fails.
>>>
>>> */
>>>
>>> if (thr_main())
>>>
>>> - return (&nc_error);
>>>
>>> + return (&nc_vars);
>>>
>>> if (thr_once(&nc_once, nc_key_init) != 0 || nc_key_error
>>> != 0)
>>>
>>> - return (&nc_error);
>>>
>>> - if ((nc_addr = (int *)thr_getspecific(nc_key)) == NULL) {
>>>
>>> - nc_addr = (int *)malloc(sizeof (int));
>>>
>>> + return (&nc_vars);
>>>
>>> + if ((nc_addr = (struct nc_thread_vars
>>> *)thr_getspecific(nc_key))
>>>
>>> + == NULL) {
>>>
>>> + nc_addr = (struct nc_thread_vars *)
>>>
>>> + calloc(1, sizeof(struct
>>> nc_thread_vars));
>>>
>>> if (thr_setspecific(nc_key, (void *)
>>> nc_addr) != 0) {
>>>
>>> if (nc_addr)
>>>
>>>
>>> free(nc_addr);
>>>
>>> - return (&nc_error);
>>>
>>> + return (&nc_vars);
>>>
>>> }
>>>
>>> - *nc_addr = 0;
>>>
>>> }
>>>
>>> return (nc_addr);
>>>
>>> }
>>>
>>> -#define nc_error (*(__nc_error()))
>>>
>>> +#define nc_error (*(&(__nc_thread()->nc_error)))
>>>
>>> +#define nc_file (*(&(__nc_thread()->nc_file)))
>>>
>>> +#define ni (*(&(__nc_thread()->nc_ni)))
>>>
>>> /*
>>>
>>> * A call to setnetconfig() establishes a /etc/netconfig "session". A
>>> session
>>>
>>> * "handle" is returned on a successful call. At the start of a
>>> session (after
>>>
>>> @@ -209,23 +211,14 @@ setnetconfig()
>>>
>>> * For multiple calls, i.e. nc_file is not NULL, we just return the
>>>
>>> * handle without reopening the netconfig db.
>>>
>>> */
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> ni.ref++;
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> -
>>>
>>> - mutex_lock(&nc_file_lock);
>>>
>>> if ((nc_file != NULL) || (nc_file = fopen(NETCONFIG, "r")) != NULL)
>>> {
>>>
>>> nc_vars->valid = NC_VALID;
>>>
>>> nc_vars->flag = 0;
>>>
>>> nc_vars->nc_configs = ni.head;
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> return ((void *)nc_vars);
>>>
>>> }
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> -
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> ni.ref--;
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> nc_error = NC_NONETCONFIG;
>>>
>>> free(nc_vars);
>>>
>>> @@ -254,13 +247,10 @@ void *handlep;
>>>
>>> /*
>>>
>>> * Verify that handle is valid
>>>
>>> */
>>>
>>> - mutex_lock(&nc_file_lock);
>>>
>>> if (ncp == NULL || nc_file == NULL) {
>>>
>>> nc_error = NC_NOTINIT;
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> return (NULL);
>>>
>>> }
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> switch (ncp->valid) {
>>>
>>> case NC_VALID:
>>>
>>> @@ -274,9 +264,7 @@ void *handlep;
>>>
>>> */
>>>
>>> if (ncp->flag == 0) { /* first time */
>>>
>>> ncp->flag = 1;
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> ncp->nc_configs = ni.head;
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> if (ncp->nc_configs != NULL) /* entry already exist
>>> */
>>>
>>> return(ncp->nc_configs->ncp);
>>>
>>> }
>>>
>>> @@ -289,12 +277,9 @@ void *handlep;
>>>
>>> * If we cannot find the entry in the list and is end of
>>> file,
>>>
>>> * we give up.
>>>
>>> */
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> if (ni.eof == 1) {
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> return(NULL);
>>>
>>> }
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> break;
>>>
>>> default:
>>>
>>> @@ -316,18 +301,13 @@ void *handlep;
>>>
>>> /*
>>>
>>> * Read a line from netconfig file.
>>>
>>> */
>>>
>>> - mutex_lock(&nc_file_lock);
>>>
>>> do {
>>>
>>> if (fgets(stringp, MAXNETCONFIGLINE, nc_file) == NULL) {
>>>
>>> free(stringp);
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> ni.eof = 1;
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> return (NULL);
>>>
>>> }
>>>
>>> } while (*stringp == '#');
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> list = (struct netconfig_list *) malloc(sizeof (struct
>>> netconfig_list));
>>>
>>> if (list == NULL) {
>>>
>>> @@ -357,7 +337,6 @@ void *handlep;
>>>
>>> * Reposition the current pointer of the handle to the
>>> last entry
>>>
>>> * in the list.
>>>
>>> */
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> if (ni.head == NULL) { /* first entry */
>>>
>>> ni.head = ni.tail = list;
>>>
>>> }
>>>
>>> @@ -367,7 +346,6 @@ void *handlep;
>>>
>>> }
>>>
>>> ncp->nc_configs = ni.tail;
>>>
>>> result = ni.tail->ncp;
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> return(result);
>>>
>>> }
>>>
>>> }
>>>
>>> @@ -402,9 +380,7 @@ void *handlep;
>>>
>>> nc_handlep->valid = NC_INVALID;
>>>
>>> nc_handlep->flag = 0;
>>>
>>> nc_handlep->nc_configs = NULL;
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> if (--ni.ref > 0) {
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> free(nc_handlep);
>>>
>>> return(0);
>>>
>>> }
>>>
>>> @@ -417,7 +393,6 @@ void *handlep;
>>>
>>> ni.eof = ni.ref = 0;
>>>
>>> ni.head = NULL;
>>>
>>> ni.tail = NULL;
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> while (q != NULL) {
>>>
>>> p = q->next;
>>>
>>> @@ -429,10 +404,8 @@ void *handlep;
>>>
>>> }
>>>
>>> free(nc_handlep);
>>>
>>> - mutex_lock(&nc_file_lock);
>>>
>>> fclose(nc_file);
>>>
>>> nc_file = NULL;
>>>
>>> - mutex_unlock(&nc_file_lock);
>>>
>>> return (0);
>>>
>>> }
>>>
>>> @@ -481,21 +454,16 @@ getnetconfigent(netid)
>>>
>>> * If all the netconfig db has been read and placed into the list
>>> and
>>>
>>> * there is no match for the netid, return NULL.
>>>
>>> */
>>>
>>> - mutex_lock(&ni_lock);
>>>
>>> if (ni.head != NULL) {
>>>
>>> for (list = ni.head; list; list = list->next) {
>>>
>>> if (strcmp(list->ncp->nc_netid, netid) == 0) {
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> return(dup_ncp(list->ncp));
>>>
>>> }
>>>
>>> }
>>>
>>> if (ni.eof == 1) { /* that's all the entries */
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> return(NULL);
>>>
>>> }
>>>
>>> }
>>>
>>> - mutex_unlock(&ni_lock);
>>>
>>> -
>>>
>>> if ((file = fopen(NETCONFIG, "r")) == NULL) {
>>>
>>> nc_error = NC_NONETCONFIG;
>>>
>>> --
>>>
>>> 1.7.9.5
>>>
>>>
>>>
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>>
>> --
>> - Alfred Perlstein
>> .- VMOA #5191, 03 vmax, 92 gs500, 85 ch250, 07 zx10
>> .- FreeBSD committer
>> _______________________________________________
>> freebsd-threads at freebsd.org mailing list
>> http://lists.freebsd.org/mailman/listinfo/freebsd-threads
>> To unsubscribe, send any mail to "freebsd-threads-unsubscribe at freebsd.org"
>
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