The Datafile PD-CD 5

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Text File | 1996-01-17 | 21.3 KB | 778 lines

; ************************************************************************** ; Copyright 1995 David Allison ; ; VV VV IIIIII SSSSS TTTTTT AA ; VV VV II SS TT AA AA ; VV VV II SSSS TT AA AA ; VV VV II SS TT AAAAAAAA ; VV IIIIII SSSS TT AA AA ; ; C++ WIMP CLASS LIBRARY ; for RISC OS ; ************************************************************************** ; ; E A S Y C + + U S E R L I C E N C E ; ---------------------------------------- ; ; This library is copyright. It is supplied as part of Easy C++ as ; source. The library may NOT be copied nor placed in any publically ; accessible place (eg a Bulletin Board). You may not sell the ; library for profit, but you may sell products which use it providing ; those products are presented as executable code and are not ; libraries themselves. The library is supplied without any ; warranty and the copyright owner cannot be held responsible for ; damage resulting from failure of any part of this library. ; ; ************************************************************************* ; ; assembly language for thread package ; AREA |Threads$code|, CODE, READONLY XEasyDebug_RegisterThreads EQU 0x8304a + 0x20000 XEasyDebug_YieldThread EQU 0x8304b + 0x20000 R0 RN 0 R1 RN 1 R2 RN 2 R3 RN 3 R4 RN 4 R5 RN 5 R6 RN 6 R7 RN 7 R8 RN 8 R9 RN 9 R10 RN 10 R11 RN 11 R12 RN 12 R13 RN 13 R14 RN 14 R15 RN 15 PC RN 15 link RN 14 SP RN 13 vp RN 12 ; variable pointer F0 FN 0 F1 FN 1 F2 FN 2 F3 FN 3 F4 FN 4 F5 FN 5 F6 FN 6 F7 FN 7 ; SWI numbers OS_WriteC EQU 0 OS_WriteS EQU 1 OS_WriteO EQU 2 OS_Newline EQU 3 OS_ReadC EQU 4 OS_CLI EQU 5 OS_Byte EQU 6 OS_Word EQU 7 OS_File EQU 8 OS_Args EQU 9 OS_Bget EQU 10 OS_Bput EQU 11 OS_Gbpb EQU 12 OS_Find EQU 13 OS_ReadLine EQU 14 OS_Control EQU 15 OS_GetEnv EQU 16 OS_Exit EQU 17 OS_SetEnv EQU 18 OS_IntOn EQU 19 OS_IntOff EQU 20 OS_CallBack EQU 21 OS_EnterOS EQU 22 OS_BreakPt EQU 23 OS_BreakCntrl EQU 24 OS_UnusedSWI EQU 25 OS_UpdateMEMC EQU 26 OS_SetCallBack EQU 27 OS_Mouse EQU 28 OS_Heap EQU 29 OS_Module EQU 30 OS_Claim EQU 31 OS_Release EQU 32 OS_ReadUnsigned EQU 33 OS_GenerateEvent EQU 34 OS_ReadVarVal EQU 35 OS_SetVarVal EQU 36 OS_GSInit EQU 37 OS_GSRead EQU 38 OS_GSTrans EQU 39 OS_BinaryToDecimal EQU 40 OS_FSControl EQU 41 OS_ChangeDynamicArea EQU 42 OS_GenerateError EQU 43 OS_ReadEscapeState EQU 44 OS_EvaluateExpression EQU 45 OS_SpriteOp EQU 46 OS_ReadPalette EQU 47 OS_ServiceCall EQU 48 OS_ReadVduVariables EQU 49 OS_ReadPoint EQU 50 OS_UpCall EQU 51 OS_CallAVector EQU 52 OS_ReadModeVariable EQU 53 OS_RemoveCursors EQU 54 OS_RestoreCursors EQU 55 OS_SWINumberToString EQU 56 OS_SWINumberFromString EQU 57 OS_ValidateAddress EQU 58 OS_CallAfter EQU 59 OS_CallEvery EQU 60 OS_RemoveTickerEvent EQU 61 OS_InstallKeyHandler EQU 62 OS_CheckModeValid EQU 63 OS_ChangeEnvironment EQU 64 OS_ClaimScreenMemory EQU 65 OS_ReadMonotonicTime EQU 66 OS_PrettyPrint EQU &44 OS_Plot EQU &45 OS_WriteN EQU &46 OS_HeapSort EQU &4F OS_CRC EQU &5B OS_ConvertStandardDateAndTime EQU 192 OS_ConvertDateAndTime EQU 193 OS_ConvertHex1 EQU 208 OS_ConvertHex2 EQU 209 OS_ConvertHex4 EQU 210 OS_ConvertHex6 EQU 211 OS_ConvertHex8 EQU 212 OS_ConvertCardinal1 EQU 213 OS_ConvertCardinal2 EQU 214 OS_ConvertCardinal3 EQU 215 OS_ConvertCardinal4 EQU 216 OS_ConvertInteger1 EQU 217 OS_ConvertInteger2 EQU 218 OS_ConvertInteger3 EQU 219 OS_ConvertInteger4 EQU 220 OS_ConvertBinary1 EQU 221 OS_ConvertBinary2 EQU 222 OS_ConvertBinary3 EQU 223 OS_ConvertBinary4 EQU 224 OS_ConvertSpacedCardinal1 EQU 225 OS_ConvertSpacedCardinal2 EQU 226 OS_ConvertSpacedCardinal3 EQU 227 OS_ConvertSpacedCardinal4 EQU 228 OS_ConvertSpacedInteger1 EQU 229 OS_ConvertSpacedInteger2 EQU 230 OS_ConvertSpacedInteger3 EQU 231 OS_ConvertSpacedInteger4 EQU 232 OS_ConvertFixedNetStation EQU 233 OS_ConvertNetStation EQU 234 OS_WriteI EQU 256 XOS_WriteC EQU 2_100000000000000000+0 XOS_WriteS EQU 2_100000000000000000+1 XOS_WriteO EQU 2_100000000000000000+2 XOS_Newline EQU 2_100000000000000000+3 XOS_ReadC EQU 2_100000000000000000+4 XOS_CLI EQU 2_100000000000000000+5 XOS_Byte EQU 2_100000000000000000+6 XOS_Word EQU 2_100000000000000000+7 XOS_File EQU 2_100000000000000000+8 XOS_Args EQU 2_100000000000000000+9 XOS_Bget EQU 2_100000000000000000+10 XOS_Bput EQU 2_100000000000000000+11 XOS_Gbpb EQU 2_100000000000000000+12 XOS_Find EQU 2_100000000000000000+13 XOS_ReadLine EQU 2_100000000000000000+14 XOS_Control EQU 2_100000000000000000+15 XOS_GetEnv EQU 2_100000000000000000+16 XOS_Exit EQU 2_100000000000000000+17 XOS_SetEnv EQU 2_100000000000000000+18 XOS_IntOn EQU 2_100000000000000000+19 XOS_IntOff EQU 2_100000000000000000+20 XOS_CallBack EQU 2_100000000000000000+21 XOS_EnterOS EQU 2_100000000000000000+22 XOS_BreakPt EQU 2_100000000000000000+23 XOS_BreakCntrl EQU 2_100000000000000000+24 XOS_UnusedSWI EQU 2_100000000000000000+25 XOS_UpdateMEMC EQU 2_100000000000000000+26 XOS_SetCallBack EQU 2_100000000000000000+27 XOS_Mouse EQU 2_100000000000000000+28 XOS_Heap EQU 2_100000000000000000+29 XOS_Module EQU 2_100000000000000000+30 XOS_Claim EQU 2_100000000000000000+31 XOS_Release EQU 2_100000000000000000+32 XOS_ReadUnsigned EQU 2_100000000000000000+33 XOS_GenerateEvent EQU 2_100000000000000000+34 XOS_ReadVarVal EQU 2_100000000000000000+35 XOS_SetVarVal EQU 2_100000000000000000+36 XOS_GSInit EQU 2_100000000000000000+37 XOS_GSRead EQU 2_100000000000000000+38 XOS_GSTrans EQU 2_100000000000000000+39 XOS_BinaryToDecimal EQU 2_100000000000000000+40 XOS_FSControl EQU 2_100000000000000000+41 XOS_ChangeDynamicArea EQU 2_100000000000000000+42 XOS_GenerateError EQU 2_100000000000000000+43 XOS_ReadEscapeState EQU 2_100000000000000000+44 XOS_EvaluateExpression EQU 2_100000000000000000+45 XOS_SpriteOp EQU 2_100000000000000000+46 XOS_ReadPalette EQU 2_100000000000000000+47 XOS_ServiceCall EQU 2_100000000000000000+48 XOS_ReadVduVariables EQU 2_100000000000000000+49 XOS_ReadPoint EQU 2_100000000000000000+50 XOS_UpCall EQU 2_100000000000000000+51 XOS_CallAVector EQU 2_100000000000000000+52 XOS_ReadModeVariable EQU 2_100000000000000000+53 XOS_RemoveCursors EQU 2_100000000000000000+54 XOS_RestoreCursors EQU 2_100000000000000000+55 XOS_SWINumberToString EQU 2_100000000000000000+56 XOS_SWINumberFromString EQU 2_100000000000000000+57 XOS_ValidateAddress EQU 2_100000000000000000+58 XOS_CallAfter EQU 2_100000000000000000+59 XOS_CallEvery EQU 2_100000000000000000+60 XOS_RemoveTickerEvent EQU 2_100000000000000000+61 XOS_InstallKeyHandler EQU 2_100000000000000000+62 XOS_CheckModeValid EQU 2_100000000000000000+63 XOS_ChangeEnvironment EQU 2_100000000000000000+64 XOS_ClaimScreenMemory EQU 2_100000000000000000+65 XOS_ReadMonotonicTime EQU 2_100000000000000000+66 XOS_PrettyPrint EQU 2_100000000000000000+&44 XOS_Plot EQU 2_100000000000000000+&45 XOS_WriteN EQU 2_100000000000000000+&46 XOS_ConvertStandardDateAndTime EQU 2_100000000000000000+192 XOS_ConvertDateAndTime EQU 2_100000000000000000+193 XOS_ConvertHex1 EQU 2_100000000000000000+208 XOS_ConvertHex2 EQU 2_100000000000000000+209 XOS_ConvertHex4 EQU 2_100000000000000000+210 XOS_ConvertHex6 EQU 2_100000000000000000+211 XOS_ConvertHex8 EQU 2_100000000000000000+212 XOS_ConvertCardinal1 EQU 2_100000000000000000+213 XOS_ConvertCardinal2 EQU 2_100000000000000000+214 XOS_ConvertCardinal3 EQU 2_100000000000000000+215 XOS_ConvertCardinal4 EQU 2_100000000000000000+216 XOS_ConvertInteger1 EQU 2_100000000000000000+217 XOS_ConvertInteger2 EQU 2_100000000000000000+218 XOS_ConvertInteger3 EQU 2_100000000000000000+219 XOS_ConvertInteger4 EQU 2_100000000000000000+220 XOS_ConvertBinary1 EQU 2_100000000000000000+221 XOS_ConvertBinary2 EQU 2_100000000000000000+222 XOS_ConvertBinary3 EQU 2_100000000000000000+223 XOS_ConvertBinary4 EQU 2_100000000000000000+224 XOS_ConvertSpacedCardinal1 EQU 2_100000000000000000+225 XOS_ConvertSpacedCardinal2 EQU 2_100000000000000000+226 XOS_ConvertSpacedCardinal3 EQU 2_100000000000000000+227 XOS_ConvertSpacedCardinal4 EQU 2_100000000000000000+228 XOS_ConvertSpacedInteger1 EQU 2_100000000000000000+229 XOS_ConvertSpacedInteger2 EQU 2_100000000000000000+230 XOS_ConvertSpacedInteger3 EQU 2_100000000000000000+231 XOS_ConvertSpacedInteger4 EQU 2_100000000000000000+232 XOS_ConvertFixedNetStation EQU 2_100000000000000000+233 XOS_ConvertNetStation EQU 2_100000000000000000+234 XOS_WriteI EQU 2_100000000000000000+256 wimp_Initialise EQU &400c0 wimp_Poll EQU &400c7 wimp_Closedown EQU &400dd wimp_ReportError EQU &400df wimp_SendMessage EQU &400e7 wimp_BlockCopy EQU &400eb wimp_SlotSize EQU &400ec wimp_ClaimFreeMemory EQU &400ee wimp_CommandWindow EQU &400ef wimp_TransferBlock EQU &400f1 wimp_ReadSysInfo EQU &400f2 wimp_StartTask EQU &400de Xwimp_Initialise EQU 2_100000000000000000+&400c0 Xwimp_Poll EQU 2_100000000000000000+&400c7 Xwimp_Closedown EQU 2_100000000000000000+&400dd Xwimp_ReportError EQU 2_100000000000000000+&400df Xwimp_SendMessage EQU 2_100000000000000000+&400e7 Xwimp_BlockCopy EQU 2_100000000000000000+&400eb Xwimp_SlotSize EQU 2_100000000000000000+&400ec Xwimp_ClaimFreeMemory EQU 2_100000000000000000+&400ee Xwimp_CommandWindow EQU 2_100000000000000000+&400ef Xwimp_TransferBlock EQU 2_100000000000000000+&400f1 Xwimp_ReadSysInfo EQU 2_100000000000000000+&400f2 Xwimp_StartTask EQU 2_100000000000000000+&400de DDEUtils_ThrowbackStart EQU &42587 DDEUtils_ThrowbackSend EQU &42588 DDEUtils_ThrowbackEnd EQU &42589 XDDEUtils_ThrowbackStart EQU 2_100000000000000000+&42587 XDDEUtils_ThrowbackSend EQU 2_100000000000000000+&42588 XDDEUtils_ThrowbackEnd EQU 2_100000000000000000+&42589 Throwback_ReasonProcessing EQU 0 Throwback_ReasonErrorDetails EQU 1 Throwback_ReasonInfoDetails EQU 2 IMPORT context_switch__13ThreadManagerFv IMPORT start2__6ThreadFv ; ; call the start2 member function for a thread. This actually starts the thread ; running ; ; entry: ; R0 = thread thread_call_start2 EXPORT thread_call_start2 B start2__6ThreadFv thread_get_time EXPORT thread_get_time STMFD SP!,{link} ; may be called in SVC mode SWI OS_ReadMonotonicTime LDMFD SP!,{PC}^ Int_bit EQU (1 << 27) USR_mode EQU 0 FIQ_mode EQU 1 IRQ_mode EQU 2 SVC_mode EQU 3 ; ; claim the callback vector ; ; entry: ; R0 = thread manager address. This is passed to the callback in R12 thread_claim_callback EXPORT thread_claim_callback STMFD SP!,{R0-R3,link} MOV R2,R0 MOV R0,#7 ADR R1,callback LDR R3,thread_callback_regs SWI XOS_ChangeEnvironment STR R1,old_callback STR R2,old_callback_r12 STR R3,old_callback_regs LDMFD SP!,{R0-R3,PC}^ old_callback DCD 0 old_callback_r12 DCD 0 old_callback_regs DCD 0 ; ; release the callback vector ; thread_release_callback EXPORT thread_release_callback STMFD SP!,{R0-R3,link} MOV R0,#7 LDR R1,old_callback LDR R2,old_callback_r12 LDR R3,old_callback_regs SWI XOS_ChangeEnvironment LDMFD SP!,{R0-R3,PC}^ ; ; start a ticker which will set the callback flag every clock tick ; ; entry: ; R0 = address of thread manager thread_start_ticker EXPORT thread_start_ticker LDR R2,alien_control CMP R2,#0 MOVNES PC,link STMFD SP!,{R0-R2,link} MOV R2,R0 MOV R0,#1 STR R0,thread_worksemaphore LDR R0,thread_poll_rate ADR R1,call_every SWI XOS_CallEvery LDMFD SP!,{R0-R2,PC}^ ; ; stop the ticker running ; ; entry: ; R0 = thread manager thread_stop_ticker EXPORT thread_stop_ticker LDR R2,alien_control CMP R2,#0 MOVNES PC,link STMFD SP!,{R0-R1,link} MOV R1,R0 ADR R0,call_every SWI XOS_RemoveTickerEvent LDMFD SP!,{R0-R1,PC}^ ; ; init the thread system for use with a debugger ; ; entry: ; R0 = thread manager thread_init EXPORT thread_init STMFD SP!,{R0-R8,link} MOV R5,R0 BL claim_heap_modifiers ADR R0,thread_worksemaphore LDR R1,ctx_swtch ADR R2,thread_callback_regs LDR R3,thread_poll_rate ADR R4,thread_system_running SWI XEasyDebug_RegisterThreads MOVVS R1,#0 ; no SWI: not under control STRVS R1,alien_control LDMVSFD SP!,{R0-R8,PC}^ CMP R0,#2 ; module running? MOVEQ R0,#1 ; yes, under control MOVNE R0,#0 ; no, we're on our own STR R0,alien_control LDMFD SP!,{R0-R8,PC}^ ; this variable tells us whether we are being controlled by some outside influence ; EasyDebug controls the threads for us if so alien_control DCD 0 ctx_swtch DCD context_switch__13ThreadManagerFv thread_system_running EXPORT thread_system_running DCD 0 thread_worksemaphore ; flag for callbacks EXPORT thread_worksemaphore DCD 0 thread_callback_regs ; current register save area EXPORT thread_callback_regs DCD 0 thread_poll_rate ; quantum poll rate EXPORT thread_poll_rate DCD 0 ; ; disable interrupts by setting the semaphore to non zero ; thread_disable_ints EXPORT thread_disable_ints MOV R0,#1 B write_ints ; ; enable the interrupts by setting the semaphore to 0 ; thread_enable_ints EXPORT thread_enable_ints MOV R0,#0 write_ints STR R0,thread_worksemaphore MOVS PC,link int_state LDR R0,thread_worksemaphore MOVS PC,link ; ; the ticker calls this every clock tick ; call_every STMFD SP!,{R0,R1,link} LDR R0,thread_worksemaphore ADD R0,R0,#1 STR R0,thread_worksemaphore CMP R0,#1 LDMNEFD SP!,{R0,R1,PC}^ MOV R1,pc ; save current processor state TEQP pc,#Int_bit+SVC_mode ; disable processor interrupts MOV R0,R0 STMFD SP!,{link} MOV R0,R12 ; load thread manager BL thread_claim_callback ; claim the callbacks SWI XOS_SetCallBack ; set the OS callback flag LDMFD SP!,{link} TEQP R1,#0 ; restore processor state MOV R0,R0 LDMFD SP!,{R0,R1,PC}^ ; ; called in usr mode by a thread wishing to give up the processor ; ; entry: ; R0 = thread manager thread_yield EXPORT thread_yield LDR R1,alien_control CMP R1,#0 SWINE XEasyDebug_YieldThread MOVNES PC,link STMFD SP!,{R0-R2,link} MOV R1,#1 STR R1,thread_worksemaphore BL thread_claim_callback SWI XOS_SetCallBack MOV R0,#0 MOV R1,#1 SWI XOS_Byte ; force a callback LDMFD SP!,{R0-R2,PC}^ ; ; this is called when the OS is returning from SVC mode to USR mode ; callback MOV R0,#1 STR R0,thread_worksemaphore ; disable callbacks TEQP PC,#SVC_mode ; enable ints MOV R0,R0 MOV R4,R12 ; save thread manager BL thread_release_callback ; release the callback handler ; save floating point regs in save area LDR R1,thread_callback_regs ADD R1,R1,#16*4 STFE F0,[R1,#0] STFE F1,[R1,#12] STFE F2,[R1,#12*2] STFE F3,[R1,#12*3] STFE F4,[R1,#12*4] STFE F5,[R1,#12*5] STFE F6,[R1,#12*6] STFE F7,[R1,#12*7] RFS R0 ; read floating status STR R0,[R1,#12*8] TEQP PC,#USR_mode ; into user mode MOV R0,R0 MOV fp,#0 ; no frame pointer MOV R0,R4 ; get the thread manager into "this" pointer BL context_switch__13ThreadManagerFv ; switch to another thread SWI OS_EnterOS ; back to supervisor mode MOV R0,R0 ; now reload the registers from the save area LDR R1,thread_callback_regs ADD R1,R1,#16*4 LDFE F0,[R1,#0] LDFE F1,[R1,#12] LDFE F2,[R1,#12*2] LDFE F3,[R1,#12*3] LDFE F4,[R1,#12*4] LDFE F5,[R1,#12*5] LDFE F6,[R1,#12*6] LDFE F7,[R1,#12*7] LDR R0,[R1,#12*8] WFS R0 ; write floating status MOV R0,#0 STR R0,thread_worksemaphore ; enable the interrupts SUB R14,R1,#16*4 ; get address of USR mode integer registers LDMIA R14,{R0-R14}^ ; load USR mode regs MOV R0,R0 TEQP PC,#Int_bit+SVC_mode ; disable ints MOV R0,R0 LDR R14,[R14,#15*4] ; load the old PC value MOVS PC,R14 ; return ; entry: ; R0 = save area thread_init_save_area EXPORT thread_init_save_area STMFD SP!,{R0,R1,link} ADD R1,R0,#16*4 STFE F0,[R1,#0] STFE F1,[R1,#12] STFE F2,[R1,#12*2] STFE F3,[R1,#12*3] STFE F4,[R1,#12*4] STFE F5,[R1,#12*5] STFE F6,[R1,#12*6] STFE F7,[R1,#12*7] RFS R0 ; read floating status STR R0,[R1,#12*8] LDMFD SP!,{R0,R1,PC}^ ; ; claim the functions that modify the heap. ; ; this claims the following functions: ; malloc ; free ; calloc ; realloc ; and makes sure that the threads are diabled on each call claimed_malloc DCD 0 my_malloc STMFD SP!,{R4-R5,link} MOV R4,R0 BL int_state MOV R5,R0 BL thread_disable_ints MOV R0,R4 MOV R14,PC LDR PC,claimed_malloc MOV R4,R0 CMP R5,#0 BLEQ thread_enable_ints MOV R0,R4 LDMFD SP!,{R4-R5,PC}^ claimed_free DCD 0 my_free STMFD SP!,{R4-R5,link} MOV R4,R0 BL int_state MOV R5,R0 BL thread_disable_ints MOV R0,R4 MOV R14,PC LDR PC,claimed_free MOV R4,R0 CMP R5,#0 BLEQ thread_enable_ints MOV R0,R4 LDMFD SP!,{R4-R5,PC}^ claimed_calloc DCD 0 my_calloc STMFD SP!,{R4-R5,link} MOV R4,R0 BL int_state MOV R5,R0 BL thread_disable_ints MOV R0,R4 MOV R14,PC LDR PC,claimed_calloc MOV R4,R0 CMP R5,#0 BLEQ thread_enable_ints MOV R0,R4 LDMFD SP!,{R4-R5,PC}^ claimed_realloc DCD 0 my_realloc STMFD SP!,{R4-R5,link} MOV R4,R0 BL int_state MOV R5,R0 BL thread_disable_ints MOV R0,R4 MOV R14,PC LDR PC,claimed_realloc MOV R4,R0 CMP R5,#0 BLEQ thread_enable_ints MOV R0,R4 LDMFD SP!,{R4-R5,PC}^ IMPORT malloc IMPORT free IMPORT realloc IMPORT calloc malloc_addr DCD malloc free_addr DCD free realloc_addr DCD realloc calloc_addr DCD calloc claim_heap_modifiers STMFD SP!,{link} LDR R0,malloc_addr ; get address of malloc ADR R1,claimed_malloc ADR R2,my_malloc BL claim_vector LDR R0,free_addr ; get address of free ADR R1,claimed_free ADR R2,my_free BL claim_vector LDR R0,calloc_addr ; get address of calloc ADR R1,claimed_calloc ADR R2,my_calloc BL claim_vector LDR R0,realloc_addr ; get address of realloc ADR R1,claimed_realloc ADR R2,my_realloc BL claim_vector LDMFD SP!,{PC}^ ; ; claim a vector ; ; entry: ; R0 = address of vector to claim ; R1 = address of word to hold old vector address ; R2 = new vector address claim_vector STMFD SP!,{R0-R3,link} MOV R3,R0 LDR R0,[R3,#0] ; get B instruction BIC R0,R0,#0xff000000 ; offset in words MOV R0,R0,LSL #2 ; offset in bytes ADD R0,R0,R3 ; add to malloc address ADD R0,R0,#8 ; add for pipelining STR R0,[R1,#0] ; store in old place SUB R0,R2,R3 ; calc offset from branch to routine SUB R0,R0,#8 ; remove pipelining MOV R0,R0,LSR #2 ; in words ORR R0,R0,#0xEA000000 ; make branch STR R0,[R3,#0] ; store in vector position LDMFD SP!,{R0-R3,PC}^ END