sl@0: // Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of the License "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // e32\klib\arm\ckdes8.cia
sl@0: // 
sl@0: //
sl@0: 
sl@0: #include <e32cia.h>
sl@0: #include <arm.h>
sl@0: #include <kernel/kernel.h>
sl@0: 
sl@0: #ifdef __DES8_MACHINE_CODED__
sl@0: 
sl@0: GLREF_C void KUDesInfoPanicBadDesType();
sl@0: GLREF_C void KUDesSetLengthPanicBadDesType();
sl@0: GLREF_C void KUDesSetLengthPanicOverflow();
sl@0: GLREF_C void Des8PanicBadDesType();
sl@0: 
sl@0: /**
sl@0: Gets information about the specified descriptor.
sl@0: 
sl@0: If the current thread is a user thread, i.e. if the mode in spsr_svc is 'User',
sl@0: then the descriptor is read using user mode privileges.
sl@0: 
sl@0: @param aSrc The descriptor for which information is to be fetched.
sl@0: @param aLength On return, set to the length of the descriptor.
sl@0: @param aMaxLength On return, set to the maximum length of the descriptor,
sl@0:                   or 1 if the descriptor is not writable.
sl@0: 
sl@0: @return Address of first byte in descriptor.
sl@0: 
sl@0: @panic KERN-EXEC 33, if aSrc is not a valid descriptor type.
sl@0: 
sl@0: @pre  Do not call from User thread if in a critical section.
sl@0: @pre  Interrupts must be enabled.
sl@0: @pre  Kernel must be unlocked.
sl@0: @pre  No fast mutex can be held.
sl@0: @pre  Call in a thread context.
sl@0: @pre  Can be used in a device driver.
sl@0: */
sl@0: EXPORT_C __NAKED__ const TUint8* Kern::KUDesInfo(const TDesC8& /*aSrc*/, TInt& /*aLength*/, TInt& /*aMaxLength*/)
sl@0: //
sl@0: // Get information about a user descriptor
sl@0: //
sl@0: 	{
sl@0: 	ASM_CHECK_PRECONDITIONS(MASK_NO_CRITICAL_IF_USER|MASK_INTERRUPTS_ENABLED|MASK_KERNEL_UNLOCKED|MASK_NOT_ISR|MASK_NOT_IDFC|MASK_NO_FAST_MUTEX);
sl@0: 	ASM_ASSERT_DATA_PAGING_SAFE		// todo: should this be ASM_ASSERT_PAGING_SAFE?
sl@0: 
sl@0: 	asm("mrs ip, spsr ");
sl@0: 	asm("tst ip, #0x0f ");			// test for user or supervisor
sl@0: 	USER_MEMORY_GUARD_OFF(eq,r12,r12);
sl@0: 	asm("ldreqt r3, [r0], #4 ");	// if user r3=type/len
sl@0: 	USER_MEMORY_GUARD_ON(eq,r12,r12);
sl@0: 	asm("bne 1f ");					// branch if supervisor
sl@0: 	asm("bic ip, r3, #0xf0000000 ");	// ip=length
sl@0: 	asm("str ip, [r1] ");			// store length
sl@0: 	asm("mvn ip, #0 ");				// ip=max length=-1 if not writeable
sl@0: 	asm("cmp r3, #0x50000000 ");
sl@0: 	asm("bcs  " CSM_Z24KUDesInfoPanicBadDesTypev);
sl@0: 	asm("eor r3, r3, r3, lsr #1 ");
sl@0: 	asm("msr cpsr_flg, r3 ");
sl@0: 	USER_MEMORY_GUARD_OFF(,r1,r1);
sl@0: 	asm("ldrcst ip, [r0], #4 ");	// if writeable ip=max length and r0+=4
sl@0: 	asm("mov r1, r0 ");				// NB can't use ldrlet r0, [r0] - see ARM ARM
sl@0: 	asm("ldrlet r0, [r1] ");		// if pointer, r0=pointer field
sl@0: 	USER_MEMORY_GUARD_ON(,r1,r1);
sl@0: 
sl@0: 	asm("2: ");
sl@0: 	asm("str ip, [r2] ");			// store max length
sl@0: 	asm("addeq r0, r0, #4 ");		// if BufCPtr, step r0 past TBufC length
sl@0: 	__JUMP(,lr);
sl@0: 
sl@0: 	asm("1: ");
sl@0: 	asm("ldr r3, [r0], #4 ");		// r3=type/len
sl@0: 	asm("bic ip, r3, #0xf0000000 ");	// ip=length
sl@0: 	asm("str ip, [r1] ");			// store length
sl@0: 	asm("mvn ip, #0 ");				// ip=max length=-1 if not writeable
sl@0: 	asm("cmp r3, #0x50000000 ");
sl@0: 	asm("bcs  " CSM_Z24KUDesInfoPanicBadDesTypev);
sl@0: 	asm("eor r3, r3, r3, lsr #1 ");
sl@0: 	asm("msr cpsr_flg, r3 ");
sl@0: 	asm("ldrcs ip, [r0], #4 ");		// if writeable ip=max length and r0+=4
sl@0: 	asm("ldrle r0, [r0] ");			// if pointer, r0=pointer field
sl@0: 	asm("b 2b ");
sl@0: 	}
sl@0: 
sl@0: 
sl@0: /**
sl@0: Sets the length of the specified descriptor.
sl@0: 
sl@0: If the current thread is a user thread, i.e. if the mode in spsr_svc is 'User',
sl@0: then the length is written using user mode privileges.
sl@0: 
sl@0: @param aDes The descriptor.
sl@0: @param aLength The new descriptor length.
sl@0: 
sl@0: @panic KERN-EXEC 34, if aDes is not a modifiable descriptor type.
sl@0: @panic KERN-EXEC 35, if aLength is longer that the maximum length of aDes.
sl@0: 
sl@0: @pre  Do not call from User thread if in a critical section.
sl@0: @pre  Interrupts must be enabled.
sl@0: @pre  Kernel must be unlocked.
sl@0: @pre  No fast mutex can be held.
sl@0: @pre  Call in a thread context.
sl@0: @pre  Can be used in a device driver.
sl@0: 
sl@0: @post The length of aDes is equal to aLength.
sl@0: @post If aDes is a TPtr type then its maximum length is equal its new length.
sl@0: */
sl@0: EXPORT_C __NAKED__ void Kern::KUDesSetLength(TDes8& /*aDes*/, TInt /*aLength*/)
sl@0: //
sl@0: // Set the length of a user descriptor, checking the length is O.K.
sl@0: //
sl@0: 	{
sl@0: 	ASM_CHECK_PRECONDITIONS(MASK_NO_CRITICAL_IF_USER|MASK_INTERRUPTS_ENABLED|MASK_KERNEL_UNLOCKED|MASK_NOT_ISR|MASK_NOT_IDFC|MASK_NO_FAST_MUTEX);
sl@0: 	ASM_ASSERT_DATA_PAGING_SAFE
sl@0: 
sl@0: 	asm("mrs ip, spsr ");
sl@0: 	asm("tst ip, #0x0f ");
sl@0: 	asm("bne  " CSM_ZN5TDes89SetLengthEi);
sl@0: 	USER_MEMORY_GUARD_OFF(,r12,r12);
sl@0: 	asm("ldrt r2, [r0], #4 ");			// r2=length/type, r0->maxlength
sl@0: 	asm("ldrt r3, [r0], #-4 ");			// r3=maxlength, r0->length/type
sl@0: 	asm("and r2, r2, #0xf0000000 ");	// r2=type field
sl@0: 	asm("cmp r2, #0x20000000 ");		// check for writeable descriptor
sl@0: 	USER_MEMORY_GUARD_ON(cc,r12,r12);
sl@0: 	asm("bcc  " CSM_Z29KUDesSetLengthPanicBadDesTypev);
sl@0: 	asm("cmp r1, r3 ");					// check length
sl@0: 	USER_MEMORY_GUARD_ON(hi,r12,r12);
sl@0: 	asm("bhi  " CSM_Z27KUDesSetLengthPanicOverflowv);
sl@0: 	asm("cmp r2, #0x40000000 ");		// check for EBufCPtr
sl@0: 	asm("orr r2, r2, r1 ");				// r2=type + new length
sl@0: 	asm("strt r2, [r0], #8 ");			// store new length, r0->ptr if EBufCPtr
sl@0: 	USER_MEMORY_GUARD_ON(ne,r12,r12);
sl@0: 	__JUMP(ne,lr);						// if not EBufCPtr finished
sl@0: 	asm("ldrt r2, [r0] ");				// r2=pointer to TBufCBase
sl@0: 	asm("strt r1, [r2] ");				// update length of TBufCBase
sl@0: 	USER_MEMORY_GUARD_ON(,r12,r12);
sl@0: 	__JUMP(,lr);
sl@0:   	}
sl@0: 
sl@0: 
sl@0: /**
sl@0: Checks whether the specified name is a valid Kernel-side object name.
sl@0: 
sl@0: A name is invalid, if it contains non-ascii characters, or any of
sl@0: the three characters: "*", "?", ":".
sl@0: 
sl@0: @param  aName The name to be checked.
sl@0: 
sl@0: @return KErrNone, if the name is valid; KErrBadName, if the name is invalid.
sl@0: 
sl@0: @pre Calling thread can be either in a critical section or not.
sl@0: @pre Interrupts must be enabled.
sl@0: @pre Kernel must be unlocked.
sl@0: @pre No fast mutex can be held.
sl@0: @pre Call in a thread context.
sl@0: @pre Can be used in a device driver.
sl@0: */
sl@0: #ifndef __KERNEL_MODE__
sl@0: #error "TDesC is not 8-bit as __KERNEL_MODE__ is not defined (see e32cmn.h)"
sl@0: #endif
sl@0: __NAKED__ EXPORT_C TInt Kern::ValidateName(const TDesC& /*aName*/)
sl@0: //
sl@0: // Check for : * or ? in descriptor, return KErrBadName if found
sl@0: //
sl@0: 	{
sl@0: 	ASM_CHECK_PRECONDITIONS(MASK_INTERRUPTS_ENABLED|MASK_KERNEL_UNLOCKED|MASK_NOT_ISR|MASK_NOT_IDFC|MASK_NO_FAST_MUTEX);
sl@0: 
sl@0: 	asm("ldr r2, [r0], #4 ");			// r2=length/type
sl@0: 	asm("cmp r2, #0x50000000 ");
sl@0: 	asm("bcs " CSM_Z19Des8PanicBadDesTypev );
sl@0: 	asm("bics r3, r2, #0xF0000000 ");	// r3=length
sl@0: 	asm("moveq r0, #0 ");				// if length=0, return KErrNone
sl@0: 	__JUMP(eq,lr);
sl@0: 	asm("eor r2, r2, r2, lsr #1 ");
sl@0: 	asm("msr cpsr_flg, r2 ");
sl@0: 	asm("addcs r0, r0, #4 ");
sl@0: 	asm("ldrle r0, [r0] ");
sl@0: 	asm("addeq r0, r0, #4 ");			// r0=this.Ptr()
sl@0: 	asm("1: ");
sl@0: 	asm("ldrb r1, [r0], #1 ");			// r1=*r0++
sl@0: 	asm("cmp r1, #0x20 ");				// is it < 0x20 ?
sl@0: 	asm("rsbhss r2, r1, #0x7f ");		// if not, compare 0x7f with char
sl@0: 	asm("bls 2f ");						// if char < 0x20 or 0x7f <= char, error
sl@0: 	asm("cmp r1, #'*' ");				// is it *
sl@0: 	asm("cmpne r1, #':' ");				// if not, is it :
sl@0: 	asm("cmpne r1, #'?' ");				// if not, is it ?
sl@0: 	asm("subnes r3, r3, #1 ");			// if none of these, decrement length
sl@0: 	asm("bne 1b ");
sl@0: 	asm("2: ");
sl@0: 	asm("cmp r3, #0 ");					// reached end of string?
sl@0: 	asm("moveq r0, #0 ");				// if we did, return KErrNone
sl@0: 	asm("mvnne r0, #%a0" : : "i" (~KErrBadName));	// else return KErrBadName
sl@0: 	__JUMP(,lr);
sl@0: 	}
sl@0: 
sl@0: extern "C" EXPORT_C __NAKED__ TInt memicmp(const TAny* /*aLeft*/, const TAny* /*aRight*/, TUint /*aLength*/)
sl@0:     {
sl@0: 	// r0 = aLeft, r1 = aRight, r2 = aLength
sl@0: 	asm("str r4, [sp, #-4]! ");
sl@0: 	asm("add r2, r2, #1 ");
sl@0: 
sl@0: 	asm("1: ");
sl@0: 	asm("subs r2, r2, #1 ");
sl@0: 	asm("ldrneb r3, [r0], #1 ");
sl@0: 	asm("beq 0f ");
sl@0: 	asm("ldrb r4, [r1], #1 ");
sl@0: 	asm("orr ip, r3, #0x20 ");
sl@0: 	asm("cmp ip, #0x61 ");
sl@0: 	asm("rsbcss ip, ip, #0x7a ");
sl@0: 	asm("eors ip, r3, r4 ");
sl@0: 	asm("andcss ip, ip, #0xdf ");
sl@0: 	asm("beq 1b ");
sl@0: 	asm("orrcs r3, r3, #0x20 ");
sl@0: 	asm("cmp r4, #0x41 ");
sl@0: 	asm("rsbcss ip, r4, #0x5a ");
sl@0: 	asm("orrcs r4, r4, #0x20 ");
sl@0: 	asm("subs r0, r3, r4 ");
sl@0: 	asm("0: ");
sl@0: 	asm("moveq r0, #0 ");
sl@0: 	asm("ldr r4, [sp], #4 ");
sl@0: 	__JUMP(,lr);
sl@0: 	}
sl@0: #endif
sl@0: 
sl@0: 
sl@0: 
sl@0: