/****************************************************************************
*
*  This code is Public Domain.
*
*  ========================================================================
*
* Description:  directives END, .STARTUP and .EXIT
*
****************************************************************************/

#include <ctype.h>

#include "globals.h"
#include "memalloc.h"
#include "parser.h"
#include "segment.h"
#include "extern.h"
#include "fixup.h"
#include "lqueue.h"
#include "tokenize.h"
#include "expreval.h"
#include "types.h"
#include "listing.h"
#include "proc.h"
#include "omf.h"

#include "myassert.h"
#if DLLIMPORT
#include "mangle.h"
#endif
#if PE_SUPPORT
#include "bin.h"
#endif

/* prototypes */
extern ret_code idata_fixup( struct code_info *, unsigned, struct expr * );

struct code_line {
    const char *src;
    const short r1;
    const short r2;
};

/* startup code for 8086 */

static const struct code_line StartupDosNear0[] = {
    { "mov %r,DGROUP", T_DX, T_NULL },
    { "mov %r,%r", T_DS, T_DX       },
    { "mov %r,%r", T_BX, T_SS       },
    { "sub %r,%r", T_BX, T_DX       },
    { "shl %r,1",  T_BX, T_NULL     },
    { "shl %r,1",  T_BX, T_NULL     },
    { "shl %r,1",  T_BX, T_NULL     },
    { "shl %r,1",  T_BX, T_NULL     },
    { "cli",       T_NULL, T_NULL   },
    { "mov %r,%r", T_SS, T_DX       },
    { "add %r,%r", T_SP, T_BX       },
    { "sti",       T_NULL, T_NULL   },
};

/* startup code for 80186+ */

static const struct code_line StartupDosNear1[] = {
    { "mov %r,DGROUP", T_AX, T_NULL },
    { "mov %r,%r",     T_DS, T_AX   },
    { "mov %r,%r",     T_BX, T_SS   },
    { "sub %r,%r",     T_BX, T_AX   },
    { "shl %r,4",      T_BX, T_NULL },
    { "mov %r,%r",     T_SS, T_AX   },
    { "add %r,%r",     T_SP, T_BX   },
};

static const struct code_line StartupDosFar[] = {
    { "mov %r,DGROUP", T_DX, T_NULL },
    { "mov %r,%r"    , T_DS, T_DX   },
};

static const struct code_line ExitOS2[] = { /* mov al, retval  followed by: */
    { "mov %r,0",     T_AH,  T_NULL  },
    { "push 1",       T_NULL,T_NULL  },
    { "push %r",      T_AX,  T_NULL  },
    { "call DOSEXIT", T_NULL,T_NULL  },
};

static const struct code_line ExitDos[] = {
    { "mov %r,4ch",  T_AH,  T_NULL  },
    { "int 21h",     T_NULL,T_NULL  },
};

static const char szStartAddr[] = {"@Startup"};

/* .STARTUP and .EXIT directives */

ret_code StartupExitDirective( int i, struct asm_tok tokenarray[] )
/*****************************************************************/
{
    int         count;
    ret_code    rc = NOT_ERROR;
    int         j;
    const struct code_line *p;
    struct expr opndx;

    LstWriteSrcLine();

    if( ModuleInfo.model == MODEL_NONE ) {
        return( EmitError( MODEL_IS_NOT_DECLARED ) );
    }
    if ( ModuleInfo.Ofssize > USE16 ) {
        return( EmitErr( DOES_NOT_WORK_WITH_32BIT_SEGMENTS, tokenarray[i].string_ptr ) );
    }

    switch( tokenarray[i].tokval ) {
    case T_DOT_STARTUP:
        count = 0;
        /* for tiny model, set current PC to 100h. */
        if ( ModuleInfo.model == MODEL_TINY )
            AddLineQueue( "org 100h" );
        AddLineQueueX( "%s::", szStartAddr );
        if( ModuleInfo.ostype == OPSYS_DOS ) {
            if ( ModuleInfo.model == MODEL_TINY )
                ;
            else {
                if( ModuleInfo.distance == STACK_NEAR ) {
                    if ( ( ModuleInfo.cpu & M_CPUMSK ) <= M_8086 ) {
                        p = StartupDosNear0;
                        count = sizeof( StartupDosNear0 ) / sizeof( StartupDosNear0[0] );
                    } else {
                        p = StartupDosNear1;
                        count = sizeof( StartupDosNear1 ) / sizeof( StartupDosNear1[0] );
                    }
                } else {
                    p = StartupDosFar;
                    count = sizeof( StartupDosFar ) / sizeof( StartupDosFar[0] );
                }
                for ( ; count ; count--, p++ )
                    AddLineQueueX( (char *)p->src, p->r1, p->r2 );
            }
        }
        ModuleInfo.StartupDirectiveFound = TRUE;
        i++; /* skip directive token */
        break;
    case T_DOT_EXIT:
        if( ModuleInfo.ostype == OPSYS_DOS ) {
            p = ExitDos;
            count = sizeof( ExitDos ) / sizeof( ExitDos[0] );
        } else {
            p = ExitOS2;
            count = sizeof( ExitOS2 ) / sizeof( ExitOS2[0] );
        }
        i++; /* skip directive token */
        if ( tokenarray[i].token != T_FINAL ) {
            if( ModuleInfo.ostype == OPSYS_OS2 ) {
                AddLineQueueX( "mov %r,%s", T_AX, tokenarray[i].tokpos );
                i = Token_Count;
            } else {
                j = i;
                if ( EvalOperand( &i, tokenarray, Token_Count, &opndx, 0 ) == ERROR )
                    return( ERROR );
                if ( opndx.kind == EXPR_CONST && opndx.value < 0x100 ) {
                    AddLineQueueX( "mov %r,4C00h + %u", T_AX, opndx.value );
                } else {
                    AddLineQueueX( "mov %r,%s", T_AL, tokenarray[j].tokpos );
                    AddLineQueueX( "mov %r,4Ch", T_AH );
                }
            }
            p++;
            count--;
        }

        for( ; count ; count--, p++ ) {
            AddLineQueueX( (char *)p->src, p->r1, p->r2 );
        }
        break;
    }

    if ( tokenarray[i].token != T_FINAL ) {
        EmitErr( SYNTAX_ERROR_EX, tokenarray[i].tokpos );
        rc = ERROR;
    }

    RunLineQueue();

    return( rc );
}

/* END directive */

ret_code EndDirective( int i, struct asm_tok tokenarray[] )
/*********************************************************/
{
    struct expr         opndx;

    DebugMsg1(("EndDirective enter\n"));

    i++; /* skip directive */

    /* v2.08: END may generate code, so write listing first */
    LstWriteSrcLine();

    /* v2.05: first parse the arguments. this allows
     * SegmentModuleExit() later to run generated code.
     */
    if( ModuleInfo.StartupDirectiveFound ) {
        /* start label behind END ignored if .STARTUP has been found */
        if( i < Token_Count && Parse_Pass == PASS_1 ) {
            EmitWarn( 2, START_ADDRESS_IGNORED );
        }
        i = Token_Count + 1;
        tokenarray[i].token = T_ID;
        tokenarray[i].string_ptr = (char *)szStartAddr;
        tokenarray[i+1].token = T_FINAL;
        tokenarray[i+1].string_ptr = "";
        Token_Count = i+1;
    }
    /* v2.11: flag EXPF_NOUNDEF added - will return ERROR if start label isn't defined */
    if( EvalOperand( &i, tokenarray, Token_Count, &opndx, EXPF_NOUNDEF ) == ERROR ) {
        return( ERROR );
    }
    if( tokenarray[i].token != T_FINAL ) {
        return( EmitErr( SYNTAX_ERROR_EX, tokenarray[i].tokpos ) );
    }

    if ( CurrStruct ) {
        while ( CurrStruct->next )
            CurrStruct = CurrStruct->next;
        EmitErr( UNMATCHED_BLOCK_NESTING, CurrStruct->sym.name );
    }
    /* v2.10: check for open PROCedures */
    ProcCheckOpen();

    /* check type of start label. Must be a symbolic code label, internal or external */
    if ( opndx.kind == EXPR_ADDR && opndx.indirect == FALSE &&
        ( opndx.mem_type == MT_NEAR || opndx.mem_type == MT_FAR || ( opndx.mem_type == MT_EMPTY && opndx.instr == T_OFFSET ) ) &&
        opndx.sym && (  opndx.sym->state == SYM_INTERNAL || opndx.sym->state == SYM_EXTERNAL ) ) {

        DebugMsg(("EndDirective: start label=%s, add=%" I32_SPEC "Xh\n", opndx.sym->name, opndx.value ));

        if ( Options.output_format == OFORMAT_OMF ) {
            struct code_info    CodeInfo;
            /* fixme: no need to create the fixup here, should be done in omf_write_modend() */
            //CodeInfo.token = T_NULL; /* v2.09: T_NULL has no entry in optable_idx[] */
            //CodeInfo.pinstr = &InstrTable[IndexFromToken( T_NULL )];
            CodeInfo.opnd[0].InsFixup = NULL;
            CodeInfo.token = T_NOP;
            CodeInfo.pinstr = &InstrTable[IndexFromToken( T_NOP )];
            CodeInfo.flags = 0;
            CodeInfo.mem_type = MT_EMPTY;
            idata_fixup( &CodeInfo, 0, &opndx );
#if FASTMEM==0
            LclFree( ModuleInfo.g.start_fixup );
#endif
            ModuleInfo.g.start_fixup = CodeInfo.opnd[0].InsFixup;
            ModuleInfo.g.start_displ = opndx.value;
        } else {
            /* Masm silently ignores start for -coff if an offset was given */
            //if ( opndx.value )
            //   emit a warning

            if ( opndx.sym->state != SYM_EXTERNAL && opndx.sym->ispublic == FALSE ) {
                opndx.sym->ispublic = TRUE;
                AddPublicData( opndx.sym );
            }
            ModuleInfo.g.start_label = opndx.sym;
        }
    } else if ( opndx.kind != EXPR_EMPTY ) {
#ifdef DEBUG_OUT
        if ( opndx.kind != EXPR_ADDR || opndx.indirect == TRUE ) {
            DebugMsg(("EndDirective: start address invalid, opndx.kind=%X indirect=%u\n", opndx.kind, opndx.indirect ));
        } else if ( opndx.sym == NULL ) {
            DebugMsg(("EndDirective: start symbol=NULL\n" ));
        } else if ( opndx.sym->state != SYM_INTERNAL && opndx.sym->state != SYM_EXTERNAL ) {
            DebugMsg(("EndDirective: start address invalid, sym->state=%X\n", opndx.sym->state ));
        } else {
            DebugMsg(("EndDirective: start address not a code label, mem_type=%Xh\n", opndx.mem_type ));
        }
#endif
        return( EmitError( OPERAND_MUST_BE_RELOCATABLE ) );
    }

    /* close open segments */
    SegmentModuleExit();

    if ( ModuleInfo.g.EndDirHook )
        ModuleInfo.g.EndDirHook( &ModuleInfo );

    ModuleInfo.EndDirFound = TRUE;

    return( NOT_ERROR );
}