ptos: ps: Add process init logic

Signed-off-by: Chloe M <chloe@mensia.org>

service/ptos/head/ps/process.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: Process management
+ * Author:      Chloe M.
+ */
+
+#ifndef _PS_PROCESS_H_
+#define _PS_PROCESS_H_ 1
+
+#include <ptapi/status.h>
+#include <ptdef.h>
+
+/* Maximum length of process name */
+#define PS_NAME_MAX 64
+
+/* Pool tag for process allocations */
+#define PS_POOL_TAG 'PS'
+
+/* Process flags */
+#define PS_USER BIT(0)   /* Set if user-level */
+
+/*
+ * Represents a running process on the machine
+ *
+ * @Name:       Name of process
+ * @Pid:        Process ID
+ * @Flags:      Initialization flags
+ */
+typedef struct {
+    CHAR Name[PS_NAME_MAX];
+    UQUAD Pid;
+    ULONG Flags;
+} PROCESS;
+
+/*
+ * Allocate and create a new process descriptor
+ *
+ * @Name:   Name of process
+ * @Flags:  Initialization flags of process
+ * @Result: Result is written here
+ */
+PT_STATUS PsCreateProcess(const CHAR *Name, ULONG Flags, PROCESS **Result);
+
+#endif  /* !_PS_PROCESS_H_ */

service/ptos/ps/process.c

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: Process management
+ * Author:      Chloe M.
+ */
+
+#include <ps/process.h>
+#include <ex/pool.h>
+#include <string.h>
+#include <atomic.h>
+
+static UQUAD ProcessId = 0;
+
+PT_STATUS
+PsCreateProcess(const CHAR *Name, ULONG Flags, PROCESS **Result)
+{
+    USIZE NameLen;
+    PROCESS *Process;
+
+    if (Name == NULL || Result == NULL) {
+        return STATUS_INVALID_PARAM;
+    }
+
+    /* TODO: Support user-level processes */
+    if (ISSET(Flags, PS_USER)) {
+        return STATUS_NOT_SUPPORTED;
+    }
+
+    NameLen = RtlStrLen(Name);
+    if (NameLen >= PS_NAME_MAX - 1) {
+        return STATUS_NAME_TOO_LONG;
+    }
+
+    Process = ExAllocatePoolWithTag(
+        POOL_NON_PAGED,
+        sizeof(*Process),
+        PS_POOL_TAG
+    );
+
+    if (Process == NULL) {
+        return STATUS_NO_MEMORY;
+    }
+
+    RtlMemCpy(Process->Name, Name, NameLen);
+    Process->Pid = AtomicIncQuad(&ProcessId);
+    Process->Flags = Flags;
+    *Result = Process;
+    return STATUS_SUCCESS;
+}