File content as of revision 20:13556e5bac04:

/*
<Copyright Header>
Copyright (c) 2012 Jordan "Earlz" Earls  <http://lastyearswishes.com>
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. The name of the author may not be used to endorse or promote products
   derived from this software without specific prior written permission.
   
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

This file is part of the MbedConsole project
*/

#include "mbedconsole.h"
#include "plEarlz.h"
#include <stdarg.h>
#include <stdint.h>
//Basically a non-conforming take on Forth, btw.

inline int internal_captureline(void* pBuffer, char const* pFormatString, ...)
{
    char*   pStringEnd = (char*)pBuffer + strlen((char*)pBuffer);
    va_list valist;
    
    va_start(valist, pFormatString);
    
    return vsprintf(pStringEnd, pFormatString, valist);
}
void printheapstats()
{
    char buffer[256];
    __heapstats(internal_captureline, buffer);
    vputs("Memory info: ");
    vputs(buffer);
}





BranchTarget *last_target=NULL;   

ErrorType pl_error=None;


enum WordType
{
    Unknown,
    Number,
    Word,
    Quote
};

uint8_t *pl_codeblock;
int pl_blockpos;
int pl_blocksize;

uint8_t* push_opcode_byte(uint8_t val)
{
    if(pl_blockpos>=pl_blocksize)
    {
        void* tmp=realloc(pl_codeblock, pl_blocksize+CODEBLOCKSTEP);
        if(tmp==NULL)
        {
            vputs("Out of memory!!");
            return;
        }
        pl_codeblock=(uint8_t*)tmp;
        pl_blocksize+=CODEBLOCKSTEP;
    }
    pl_codeblock[pl_blockpos]=val;
    pl_blockpos++;
    return &pl_codeblock[pl_blockpos-1];
}
Opcode* push_opcode(Opcode val)
{
    if(pl_blockpos>=pl_blocksize)
    {
        void* tmp=realloc(pl_codeblock, pl_blocksize+CODEBLOCKSTEP);
        if(tmp==NULL)
        {
            vputs("Out of memory!!");
            return;
        }
        pl_codeblock=(uint8_t*)tmp;
        pl_blocksize+=CODEBLOCKSTEP;
    }
    pl_codeblock[pl_blockpos]=(uint8_t)val;
    pl_blockpos++;
    return (Opcode*)&pl_codeblock[pl_blockpos-1];
}
uint16_t* push_opcode_word(uint16_t val)
{
    if(pl_blockpos>=pl_blocksize)
    {
        void* tmp=realloc(pl_codeblock, pl_blocksize+CODEBLOCKSTEP);
        if(tmp==NULL)
        {
            vputs("Out of memory!!");
            return;
        }
        pl_codeblock=(uint8_t*)tmp;
        pl_blocksize+=CODEBLOCKSTEP;
    }
    *(uint16_t*)&pl_codeblock[pl_blockpos]=val;
    pl_blockpos+=2;
    return (uint16_t*)(&pl_codeblock[pl_blockpos-2]);
}
uint32_t* push_opcode_dword(uint32_t val)
{
    if(pl_blockpos>=pl_blocksize)
    {
        void* tmp=realloc(pl_codeblock, pl_blocksize+CODEBLOCKSTEP);
        if(tmp==NULL)
        {
            vputs("Out of memory!!");
            return;
        }
        pl_codeblock=(uint8_t*)tmp;
        pl_blocksize+=CODEBLOCKSTEP;
    }
    *(uint32_t*)&pl_codeblock[pl_blockpos]=val;
    pl_blockpos+=4;
    return (uint32_t*)&pl_codeblock[pl_blockpos-4];
}
void new_codeblock(bool freeit)
{
    if(freeit)
    {
        free(pl_codeblock);
    }
    pl_codeblock=(uint8_t*)malloc(CODEBLOCKSTEP);
    pl_blockpos=0;
    pl_blocksize=CODEBLOCKSTEP;
    last_target=NULL;
}
int execute_codeblock()
{
    return forth_execute(pl_codeblock, pl_blockpos);
}
 

void push_target(int address)
{
    BranchTarget* target=(BranchTarget*)malloc(sizeof(BranchTarget));
    target->previous=last_target;
    target->target=address;
    last_target=target;
}
void pop_target()
{
    if(last_target==NULL)
    {
        vputs("Unmatched control statement!\n");
        return;
    }
    volatile void* tmp=last_target;
    last_target=last_target->previous;
    free((void*)tmp);
}
inline void write_blockword(int pos,uint16_t val)
{
    *(uint16_t*)&pl_codeblock[pos]=val;
}

int compile_word(char *word, WordType type) //returns 0 for success, 1 for ending word found, -1 for error
{
    if(type==Number){
        push_opcode(Push);
        push_opcode_dword(atoi(word));
    }else{
        if(word[1]==0) //check the quick builtins first
        {
            if(word[0]=='.'){
                push_opcode(CallInt);
                push_opcode_dword((uint32_t)&bi_print);
            }else if(word[0]==';')
            {
                push_opcode(Ret);
                //execute!
                return 1;
            }else if(word[0]=='+'){
                push_opcode(Add);
            }else if(word[0]=='/'){
                push_opcode(Div);
            }else if(word[0]=='-'){
                push_opcode(Sub);
            }else if(word[0]=='!'){
                //pl_push(pl_pop()-pl_pop());
            }else if(word[0]=='%'){
                push_opcode(Mod);
            }else if(word[0]=='*'){
                push_opcode(Mul);
            }else if(word[0]=='!'){
                //push_opcode(Store);
            }else if(word[0]=='?'){
                pl_push(*(int*)pl_pop());
            }else if(word[0]=='='){
                pl_push(pl_pop() == pl_pop());
            }else if(word[0]=='`'){
                pl_push(pl_pop()>0);
            }else if(word[0]=='$'){
                //print string (address on stack
            }else if(word[0]=='['){
                //begin quotation
                push_opcode(Push);
                push_opcode_word(pl_blockpos+3);
                push_opcode(Branch);
                push_target(pl_blockpos);
                push_opcode_word(0);
            }else if(word[0] == ']'){
                //end quotation
                push_opcode(Ret);
                write_blockword(last_target->target, pl_blockpos);
                pop_target();
            }
        }else if(strlcmp("if", word, 3)==0){
            push_opcode(BranchFalse);
            push_target(pl_blockpos);
            push_opcode_word(0);
        }else if(strlcmp("else", word, 5)==0){
            push_opcode(Branch);
            int tmp=pl_blockpos;
            push_opcode_word(0); 
            write_blockword(last_target->target,pl_blockpos);
            pop_target(); 
            push_target(tmp); //have to do it after we pop it or we fall into an infinite loop!
        }else if(strlcmp("end", word, 4)==0){
            write_blockword(last_target->target,(uint16_t)pl_blockpos);
            pop_target();
        }else if(strlcmp("tif", word, 4)==0){
            /**
            swap value 2 behind stack to front
            call.true 1 from stack
            call.false top of stack
            _label:
            **/
            //alloca(10);
            push_opcode(Push);
            push_opcode_dword(3);
            push_opcode(Pick);
            push_opcode(BranchFalse);
            //push_opcode_word(pl_blockpos+
            
        }else{
            vputs("I don't know the word '");
            vputs(word);
            vputs("'\n");
        }
    }
    return 0;
}



void parse_line(char *line)
{
    int len=strlen(line);
    char word[16];
    word[0]=0;
    int wordpos=0;
    WordType type=Unknown;
    for(int i=0;i<len;i++)
    {
        char c=line[i];
        if(is_whitespace(c) || c=='\\')
        {
            if(word[0]!=0)
            {
                word[wordpos]=0;
                
                int tmp=compile_word(word,type);
                if(tmp==1)
                {
                    execute_codeblock();
                    new_codeblock(true);
                }
                word[0]=0;
            }
            wordpos=0;
            type=Unknown;
            if(c=='\\'){
                return; //rest is a comment
            }
        }else if(is_numeric(c)){
            if(type==Unknown){
                type=Number;
            }
            word[wordpos]=c;
            wordpos++;
        }else if(is_quote(c)){
            push_opcode(LoadStr);
            for(;i<len;i++)
            {
                //char c=line[
            }
            vputs("This isn't supported yet foo!");
            return;
        }else{
            if(type==Number){
                vputs("Syntax Error! Unexpected symbol in the middle of a number");
                return;
            }
            type=Word;
            word[wordpos]=c;
            wordpos++;
        }
    }
}


void tester()
{
    printf("foo!");
}

int pl_shell()
{
    vputs(">>plEarlz -- A forth-ish shell<<\n");
    printheapstats();
    vputs("\n");
    char *line=(char*)malloc(MAXLINELENGTH);
    sprintf(line, "Stack Size: %i; Max Recursion Level %i; Loaded WORDs: %i", MAXSTACK, MAXTEMPSTACK, 0);
    vputs(line);
    sprintf(line, "Max line length: %i\n", MAXLINELENGTH);
    vputs(line);
    new_codeblock(false);
    char *tmp=(char*)malloc(32); //for constructing words/elements
    while(1)
    {
        vputs("cmd> ");
        vgetsl(line, MAXLINELENGTH);
        line[MAXLINELENGTH-1]=0;
        int len=strlen(line);
        line[len]='\n';
        line[len+1]=0;
        parse_line(line);
    
    }
    free(line);
    free(tmp);
    return 0;
}