Commit f5da908c authored by Hallvard Furuseth's avatar Hallvard Furuseth
Browse files

thread_keys is a (poor) open-addessed hash table, but it lacked a

"deleted item" mark.  Add DELETED_THREAD_CTX.
Also improve the hash function a bit, and make the hash unsigned.
parent 8a928252
......@@ -56,15 +56,23 @@ typedef struct ldap_int_thread_userctx_s {
static ldap_pvt_thread_t tid_zero;
/* Thread ID -> context mapping.
/* Thread ID -> context mapping (poor open-addressed hash table).
* Protected by ldap_pvt_thread_pool_mutex except during pauses,
* when it is reserved for ldap_pvt_thread_pool_purgekey().
*/
static struct {
ldap_pvt_thread_t id;
ldap_int_thread_userctx_t *ctx;
ldap_int_thread_userctx_t *ctx; /* set when id != tid_zero */
# define DELETED_THREAD_CTX (&ldap_int_main_thrctx + 1) /* dummy addr */
} thread_keys[LDAP_MAXTHR];
#define TID_HASH(tid, hash) do { \
unsigned const char *ptr_ = (unsigned const char *)&(tid); \
unsigned i_; \
for (i_ = 0, (hash) = ptr_[0]; ++i_ < sizeof(tid);) \
(hash) += ((hash) << 5) ^ ptr_[i_]; \
} while(0)
typedef struct ldap_int_thread_ctx_s {
union {
......@@ -324,9 +332,6 @@ ldap_pvt_thread_pool_init (
return(0);
}
#define TID_HASH(tid, hash) do { unsigned i; \
unsigned char *ptr = (unsigned char *)&(tid); \
for (i=0, hash=0; i<sizeof(tid); i++) hash += ptr[i]; } while(0)
int
ldap_pvt_thread_pool_submit (
......@@ -634,7 +639,7 @@ ldap_int_thread_pool_wrapper (
struct ldap_int_thread_pool_s *pool = xpool;
ldap_int_thread_ctx_t *ctx;
ldap_int_thread_userctx_t uctx;
int i, keyslot, hash;
unsigned i, keyslot, hash;
if (pool == NULL)
return NULL;
......@@ -734,7 +739,7 @@ ldap_int_thread_pool_wrapper (
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
thread_keys[keyslot].ctx = NULL;
thread_keys[keyslot].ctx = DELETED_THREAD_CTX;
thread_keys[keyslot].id = tid_zero;
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
......@@ -876,8 +881,8 @@ void ldap_pvt_thread_pool_purgekey( void *key )
ldap_int_thread_userctx_t *ctx;
for ( i=0; i<LDAP_MAXTHR; i++ ) {
if ( thread_keys[i].ctx ) {
ctx = thread_keys[i].ctx;
ctx = thread_keys[i].ctx;
if ( ctx && ctx != DELETED_THREAD_CTX ) {
for ( j=0; j<MAXKEYS; j++ ) {
if ( ctx->ltu_key[j].ltk_key == key ) {
if (ctx->ltu_key[j].ltk_free)
......@@ -902,7 +907,7 @@ void ldap_pvt_thread_pool_purgekey( void *key )
void *ldap_pvt_thread_pool_context( )
{
ldap_pvt_thread_t tid;
int i, hash;
unsigned i, hash;
ldap_int_thread_userctx_t *ctx;
tid = ldap_pvt_thread_self();
......@@ -910,12 +915,16 @@ void *ldap_pvt_thread_pool_context( )
return &ldap_int_main_thrctx;
TID_HASH( tid, hash );
i = hash &= (LDAP_MAXTHR-1);
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
for (i = hash & (LDAP_MAXTHR-1);
!ldap_pvt_thread_equal(thread_keys[i].id, tid_zero) &&
!ldap_pvt_thread_equal(thread_keys[i].id, tid);
i = (i+1) & (LDAP_MAXTHR-1));
ctx = thread_keys[i].ctx;
do {
ctx = thread_keys[i].ctx;
if ( ctx != DELETED_THREAD_CTX )
if ( ldap_pvt_thread_equal(thread_keys[i].id, tid) || !ctx )
goto done;
} while ( (i = (i+1) & (LDAP_MAXTHR-1)) != hash );
ctx = NULL;
done:
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
return ctx;
......
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