Mon Jul 20 02:31:05 1998 Ross Johnson <rpj@ixobrychus.canberra.edu.au>

	* private.c (_pthread_getthreadindex): Implement.

	* pthread.h: Add application static data dependent on
	_PTHREADS_BUILD_DLL define. This is needed to avoid allocating
	non-sharable static data within the pthread DLL.

	* implement.h: Add _pthread_cleanup_stack_t, _pthread_cleanup_node_t
	and _PTHREAD_HASH_INDEX.

	* exit.c (pthread_exit): Begin work on cleanup and de-allocate
	thread-private storage.

	* create.c (pthread_create): Add thread to thread table.
	Keep a thread-private copy of the attributes with default values
	filled in when necessary. Same for the cleanup stack. Make
	pthread_create C run-time library friendly by using _beginthreadex()
	instead of CreateThread(). Fix error returns.

Sun Jul 19 16:26:23 1998  Ross Johnson  <rpj@ixobrychus.canberra.edu.au>

	* implement.h: Rename pthreads_thread_count to _pthread_threads_count.
	Create _pthread_threads_thread_t struct to keep thread specific data.

	* create.c: Rename pthreads_thread_count to _pthread_threads_count.
	(pthread_create): Handle errors from CreateThread().

1 files changed, 110 insertions, 32 deletions

diff --git a/create.c b/create.c
index 7a374bb..6897a9f 100644
--- a/create.c
+++ b/create.c
@@ -6,23 +6,24 @@
  * thread.
  */
 
+#include <windows.h>
+#include <process.h>
 #include "pthread.h"
 #include "implement.h"
 
-/* FIXME: There must be a Win32 routine to get this value. */
-DWORD pthread_threads_count = 0;
-
 int
 pthread_create(pthread_t *thread, const pthread_attr_t *attr,
 	       void * (*start_routine) (void *), void * arg)
 {
   /* Call Win32 CreateThread.
      Map attributes as correctly as possible.
+     The passed in attr structure will be modified by this routine
+     to reflect any default values used. This is POSIX semantics.
   */
-  HANDLE handle;
-  DWORD  flags = 0; /* Always 0 for POSIX threads */
-  DWORD  stack = PTHREAD_STACK_MIN;
-  LPSECURITY_ATTRIBUTES  security = NULL;
+  HANDLE   handle = NULL;
+  unsigned flags;
+  unsigned stack;
+  void *   security = NULL;
 
   /* FIXME: This needs to be moved into process space. 
      Perhaps into a structure that contains all
@@ -32,34 +33,111 @@ pthread_create(pthread_t *thread, const pthread_attr_t *attr,
    */
   SECURITY_ATTRIBUTES security_attr;
   DWORD  threadID;
+  int t;
+  int ret = 0; /* Success unless otherwise set */
+  char * privmem;
+  pthread_attr_t * attr_copy;
+  _pthread_cleanup_stack_t * cleanup_stack;
+
+  /* Use and modify attr_copy. Only after we've succeeded in creating the
+     new thread can we modify any passed-in structures.
 
-  if (pthread_threads_count >= PTHREAD_THREADS_MAX)
+     We use one malloc() to get all of our heap space and then allocate
+     it further.
+   */
+  if (NULL == (privmem = (char) malloc(sizeof(pthread_attr_t) + 
+				       sizeof(_pthread_cleanup_stack_t) +
+				       sizeof(DWORD)))) {
     return EAGAIN;
+  }
+
+  attr_copy = (pthread_attr_t *) privmem;
+  /* Force the next to a DWORD boundary. 
+     This is all compile time arithmetic. 
+   */
+  cleanup_stack = 
+    (_pthread_cleanup_stack_t *) &privmem[((sizeof(pthread_attr_t) / 
+					    sizeof(DWORD)) + 1) 
+					 * sizeof(DWORD)];
+
+  (void) memcpy(attr_copy, attr);
+  
+
+  /* CRITICAL SECTION */
+  pthread_mutex_lock(&_pthread_count_mutex);
+
+  if (_pthread_threads_count < PTHREAD_THREADS_MAX) {
+    switch (attr)
+      {
+      case NULL:
+	/* Use POSIX default attributes */
+	stack = attr_copy->stacksize = PTHREAD_STACK_MIN;
+	break;
+      default:
+	/* Map attributes */
+	if (attr_copy.stacksize != NULL)
+	  stack = (DWORD) attr_copy->stacksize;
+	else
+	  stack = attr_copy->stacksize = PTHREAD_STACK_MIN;
+	break;
+      }
+
+    flags = 1; /* Start suspended and resume at the last moment */
 
-  switch (attr)
-    {
-    case NULL:
-      /* Use POSIX default attributes */
-      break;
-    default:
-      /* Map attributes */
-      if (attr->stacksize != NULL)
-	stack = (DWORD) attr->stacksize;
-      break;
+    handle = (HANDLE) _beginthreadex(security,
+				   stack,
+				   (unsigned (_stdcall *)(void *)) start_routine,
+				   arg,
+				   flags,
+				   &threadID);
+
+    if (handle != NULL) {
+      /* We have a new thread */
+      _pthread_threads_count++;
+
+      /* The hash table works as follows:
+	 hash into the table,
+	 if the slot is occupied then start single stepping from there
+	 until we find an available slot.
+
+	 There is at least one slot available at this point.
+       */
+      t = _PTHREAD_HASH_INDEX(handle);
+      while ((_pthread_threads_table[t])->thread != NULL) {
+	t++;
+	if (t == PTHREAD_THREADS_MAX)
+	  t = 0; /* Wrap around to the first slot */
+      }
+      if ((_pthread_threads_table[t])->thread != NULL) {
+	/* INTERNAL ERROR */
+      } else {
+	(_pthread_threads_table[t])->thread = handle;
+	(_pthread_threads_table[t])->attr = attr_copy;
+	(_pthread_threads_table[t])->cleanupstack = cleanup_stack;
+      }
+    } else {
+      ret = EAGAIN;
     }
+  } else {
+    ret = EAGAIN;
+  }
 
-  /* FIXME: I don't have error return values to work with so
-     I'm assuming this always succeeds (obviously not).
-   */
-  handle = CreateThread(security,
-			stack,
-			start_routine,
-			arg,
-			flags,
-			&threadID);
-
-  *thread = (pthread_t) handle;
-  pthread_threads_count++;
-  return 0;
-}
+  /* Let others in as soon as possible. */
+  pthread_mutex_unlock(&_pthread_count_mutex);
+  /* END CRITICAL SECTION */
+
+  if (ret == 0) {
+    *thread = (pthread_t) handle;
+    (void) memcpy(attr, attr_copy);
 
+    /* POSIX threads are always running after creation.
+       Start the thread only after passed-in structures have been
+       modified to avoid race conditions.
+     */
+    ResumeThread(handle);
+  } else {
+    free(privmem);
+  }
+
+  return ret;
+}