* threads.c
* - Thread and process handling
*/
+#define _SIGNAL_H_ // Stop the acess signal.h being used
+#define _HEAP_H_ // Stop heap.h being imported (collides with stdlib heap)
+#define _VFS_EXT_H // Stop vfs_ext.h being imported (collides with fd_set)
+#undef CLONE_VM // Such a hack
+#include <arch.h>
+#undef NULL // Remove acess definition
#include <acess.h>
+#include <mutex.h>
+#include <semaphore.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <stdint.h>
+#include "/usr/include/signal.h"
+#include <SDL/SDL.h>
+
+// === IMPORTS ===
+void VFS_CloneHandleList(int PID);
// === STRUCTURES ===
+#if 0
+typedef struct sState
+{
+ void *CurState;
+ Uint SP, BP, IP;
+} tState;
+#endif
+
typedef struct sThread
{
+ struct sThread *GlobalNext;
struct sThread *Next;
+
+ int KernelTID;
+
tTID TID, PID;
tUID UID, GID;
char *ThreadName;
+ int State; // 0: Dead, 1: Active, 2: Paused, 3: Asleep
+ int ExitStatus;
+ #if 0
+ tState CurState;
+ #endif
+
+ // Threads waiting for this thread to exit.
+ // Quit logic:
+ // - Wait for `WaitingThreads` to be non-null (maybe?)
+ // - Wake first in the queue, wait for it to be removed
+ // - Repeat
+ // - Free thread and quit kernel thread
+ struct sThread *WaitingThreads;
+ struct sThread *WaitingThreadsEnd;
+
// Config?
Uint Config[NUM_CFG_ENTRIES];
} tThread;
+// === PROTOTYPES ===
+ int Threads_Wake(tThread *Thread);
+
// === GLOBALS ===
-tThread *gpThreads;
-__thread tThread *gpCurrentThread;
+tThread gThreadZero = {
+ State: 1,
+ ThreadName: "ThreadZero"
+};
+tThread *gpThreads = &gThreadZero;
+__thread tThread *gpCurrentThread = &gThreadZero;
+ int giThreads_NextThreadID = 1;
// === CODE ===
+void Threads_Dump(void)
+{
+ tThread *thread;
+ for( thread = gpThreads; thread; thread = thread->GlobalNext )
+ {
+ Log_Log("Threads", "TID %i (%s), PID %i",
+ thread->TID, thread->ThreadName, thread->PID);
+ Log_Log("Threads", "User: %i, Group: %i",
+ thread->UID, thread->GID);
+ Log_Log("Threads", "Kernel Thread ID: %i",
+ thread->KernelTID);
+ }
+}
+
+tThread *Threads_GetThread(int TID)
+{
+ tThread *thread;
+ for( thread = gpThreads; thread; thread = thread->GlobalNext )
+ {
+ if( thread->TID == TID )
+ return thread;
+ }
+ return NULL;
+}
+
+/**
+ * \brief Clone a thread control block (with a different TID)
+ */
+tThread *Threads_CloneTCB(tThread *TemplateThread)
+{
+ tThread *ret = malloc(sizeof(tThread));
+
+ memcpy(ret, TemplateThread, sizeof(tThread));
+
+ ret->TID = giThreads_NextThreadID ++;
+
+ ret->ThreadName = strdup(TemplateThread->ThreadName);
+
+ ret->WaitingThreads = NULL;
+ ret->WaitingThreadsEnd = NULL;
+
+ // Add to the end of the queue
+ // TODO: Handle concurrency issues
+ ret->GlobalNext = gpThreads;
+ gpThreads = ret;
+
+ return ret;
+}
+
tUID Threads_GetUID() { return gpCurrentThread->UID; }
tGID Threads_GetGID() { return gpCurrentThread->GID; }
tTID Threads_GetTID() { return gpCurrentThread->TID; }
tPID Threads_GetPID() { return gpCurrentThread->PID; }
+int Threads_SetUID(int *Errno, tUID NewUID)
+{
+ if(Threads_GetUID() != 0) {
+ if(Errno) *Errno = -EACCES;
+ return -1;
+ }
+
+ gpCurrentThread->UID = NewUID;
+ return 0;
+}
+
+int Threads_SetGID(int *Errno, tGID NewGID)
+{
+ if(Threads_GetUID() != 0) {
+ if(Errno) *Errno = -EACCES;
+ return -1;
+ }
+
+ gpCurrentThread->GID = NewGID;
+ return 0;
+}
+
Uint *Threads_GetCfgPtr(int Index)
{
+ if( Index < 0 || Index >= NUM_CFG_ENTRIES )
+ return NULL;
+ if( !gpCurrentThread )
+ return NULL;
return &gpCurrentThread->Config[Index];
}
+
+int Threads_WaitTID(int TID, int *Status)
+{
+ // Any Child
+ if(TID == -1) {
+ Log_Error("Threads", "TODO: Threads_WaitTID(TID=-1) - Any Child");
+ return -1;
+ }
+
+ // Any peer/child thread
+ if(TID == 0) {
+ Log_Error("Threads", "TODO: Threads_WaitTID(TID=0) - Any Child/Sibling");
+ return -1;
+ }
+
+ // TGID = abs(TID)
+ if(TID < -1) {
+ Log_Error("Threads", "TODO: Threads_WaitTID(TID<0) - TGID");
+ return -1;
+ }
+
+ // Specific Thread
+ if(TID > 0) {
+
+ tThread *thread = Threads_GetThread(TID);
+ tThread *us = gpCurrentThread;
+ if(!thread) return -1;
+
+ us->Next = NULL;
+ us->State = 3;
+ if(thread->WaitingThreadsEnd)
+ {
+ thread->WaitingThreadsEnd->Next = us;
+ thread->WaitingThreadsEnd = us;
+ }
+ else
+ {
+ thread->WaitingThreads = us;
+ thread->WaitingThreadsEnd = us;
+ }
+
+ while(thread->State != 0)
+ pause();
+
+ if(Status) *Status = thread->ExitStatus;
+ thread->WaitingThreads = thread->WaitingThreads->Next;
+ us->Next = NULL;
+
+ return TID;
+ }
+
+ return 0;
+}
+
+void Threads_Sleep(void)
+{
+ // TODO: Add to a sleeping queue
+ pause();
+}
+
+void Threads_Yield(void)
+{
+// yield();
+}
+
+void Threads_Exit(int TID, int Status)
+{
+ tThread *toWake;
+
+// VFS_Handles_Cleanup();
+
+ #if 1
+ // Wait for the thread to be waited upon
+ while( gpCurrentThread->WaitingThreads == NULL )
+ SDL_Delay(10);
+ #endif
+
+ while( (toWake = gpCurrentThread->WaitingThreads) )
+ {
+ Threads_Wake(toWake);
+
+ while(gpCurrentThread->WaitingThreads == toWake)
+ SDL_Delay(10);
+ }
+}
+
+int Threads_Wake(tThread *Thread)
+{
+ kill( Thread->KernelTID, SIGUSR1 );
+ return 0;
+}
+
+int Threads_WakeTID(tTID TID)
+{
+ tThread *thread;
+ thread = Threads_GetThread(TID);
+ if( !thread ) return -1;
+ return Threads_Wake(thread);
+}
+
+int Threads_CreateRootProcess(void)
+{
+ tThread *thread = Threads_CloneTCB(&gThreadZero);
+ thread->PID = thread->TID;
+
+ // Handle list is created on first open
+
+ return thread->PID;
+}
+
+int Threads_Fork(void)
+{
+ tThread *thread = Threads_CloneTCB(gpCurrentThread);
+ thread->PID = thread->TID;
+ // Duplicate the VFS handles (and nodes) from vfs_handle.c
+
+ VFS_CloneHandleList(thread->PID);
+
+ return thread->PID;
+}
+
+int Mutex_Acquire(tMutex *Mutex)
+{
+ if(!Mutex->Protector.IsValid) {
+ pthread_mutex_init( &Mutex->Protector.Mutex, NULL );
+ Mutex->Protector.IsValid = 1;
+ }
+ pthread_mutex_lock( &Mutex->Protector.Mutex );
+ return 0;
+}
+
+void Mutex_Release(tMutex *Mutex)
+{
+ pthread_mutex_unlock( &Mutex->Protector.Mutex );
+}
+
+void Semaphore_Init(tSemaphore *Sem, int InitValue, int MaxValue, const char *Module, const char *Name)
+{
+ memset(Sem, 0, sizeof(tSemaphore));
+ // HACK: Use `Sem->Protector` as space for the semaphore pointer
+ *(void**)(&Sem->Protector) = SDL_CreateSemaphore(InitValue);
+}
+
+int Semaphore_Wait(tSemaphore *Sem, int MaxToTake)
+{
+ SDL_SemWait( *(void**)(&Sem->Protector) );
+ return 1;
+}
+
+int Semaphore_Signal(tSemaphore *Sem, int AmmountToAdd)
+{
+ int i;
+ for( i = 0; i < AmmountToAdd; i ++ )
+ SDL_SemPost( *(void**)(&Sem->Protector) );
+ return AmmountToAdd;
+}
+
+#if 0
+void Threads_Sleep()
+{
+ gpCurrentThread->State = 3;
+ if( setjmp(&gpCurrentThread->CurState) == 0 ) {
+ // Return to user wait
+ // Hmm... maybe I should have a "kernel" thread for every "user" thread
+ }
+ else {
+ // Just woken up, return
+ return ;
+ }
+}
+
+int SaveState(tState *To)
+{
+ Uint ip;
+ __asm__ __volatile__(
+ "call 1f;\n\t"
+ "1f:\n\t"
+ "pop %%eax"
+ : "=a" (ip)
+ : );
+ // If we just returned
+ if(!ip) return 1;
+
+ To->IP = ip;
+ __asm__ __volatile__ ("mov %%esp, %1" : "=r"(To->SP));
+ __asm__ __volatile__ ("mov %%ebp, %1" : "=r"(To->BP));
+}
+#endif
+