diff options
Diffstat (limited to 'bfinter2.c')
-rw-r--r-- | bfinter2.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/bfinter2.c b/bfinter2.c new file mode 100644 index 0000000..8801090 --- /dev/null +++ b/bfinter2.c @@ -0,0 +1,253 @@ +#include <stdio.h> +#include <stdarg.h> +#include <stdlib.h> +#include <string.h> +#include <stdint.h> +#include <inttypes.h> +#include <fcntl.h> +#include <assert.h> +#include <sys/stat.h> + +typedef int8_t i8; +typedef uint8_t u8; +typedef int64_t i64; + +__attribute__((noreturn)) +static void dieperror(const char *func){ + perror(func); + exit(1); +} + +__attribute__((noreturn,format(printf,1,2))) +static void die(const char *format,...){ + va_list ap; + va_start(ap,format); + vfprintf(stderr,format,ap); + va_end(ap); + exit(1); +} + + +static int gcd(int a,int b){ + while(b!=0){ + int t=a%b; + a=b; + b=t; + } + return a; +} + + +static char* readfile(const char *fname,i64 *length){ + int fd=open(fname,O_RDONLY); + if(fd<0)dieperror("open"); + struct stat statbuf; + if(fstat(fd,&statbuf)<0)dieperror("fstat"); + *length=statbuf.st_size; + FILE *f=fdopen(fd,"r"); + assert(f); + char *mem=malloc(*length+1); + assert(mem); + if((i64)fread(mem,1,*length,f)<*length)die("Invalid file length"); + fclose(f); + return mem; +} + +enum instype { + IADD, + ISET, + ISLIDE, + ILOOP1, + ILOOP2, + IINPUT, + IOUTPUT, + IDEBUG, +}; + +struct ins { + enum instype type; + int off; + u8 value; +}; + +struct program { + struct ins *ins; + i64 len,cap; +}; + +static struct program p_make(void){ + struct program p; + p.cap=16; + p.len=0; + p.ins=malloc(p.cap*sizeof(struct ins)); + assert(p.ins); + return p; +} + +static void p_ensure(struct program *p,i64 len){ + if(len>p->cap){ + p->cap=len+16; + p->ins=realloc(p->ins,p->cap*sizeof(struct ins)); + assert(p->ins); + } +} + +static void p_insert(struct program *p,i64 i,struct ins ins){ + p_ensure(p,p->len+1); + memmove(p->ins+i+1,p->ins+i,(p->len-i)*sizeof(struct ins)); + p->ins[i]=ins; + p->len++; +} + +static void p_append(struct program *p,struct ins ins){ + p_ensure(p,p->len+1); + p->ins[p->len]=ins; + p->len++; +} + +static void p_erase(struct program *p,i64 i){ + memmove(p->ins+i,p->ins+i+1,(p->len-i)*sizeof(struct ins)); + p->len--; +} + +static void p_dump(const struct program p,FILE *f){ + for(i64 i=0;i<p.len;i++){ + switch(p.ins[i].type){ + case IADD: + fprintf(f,"+%d,%d ", + p.ins[i].off,(int)(i8)p.ins[i].value); + break; + case ISET: + fprintf(f,"S%d,%d ", + p.ins[i].off,(int)(i8)p.ins[i].value); + break; + case ISLIDE: + fprintf(f,"%c%d ", + p.ins[i].off<0?'<':'>',p.ins[i].off); + break; + case IINPUT: + fprintf(f,"I%d ",p.ins[i].off); + break; + case IOUTPUT: + fprintf(f,"O%d ",p.ins[i].off); + break; + case ILOOP1: + fprintf(f,"[%d ",p.ins[i].off); + break; + case ILOOP2: + fprintf(f,"] "); + break; + case IDEBUG: + fprintf(f,"# "); + break; + } + } + fputc('\n',f); +} + +static void p_run(const struct program p){ + i64 *jm=calloc(p.len,sizeof(i64)); + assert(jm); + { + i64 cap=16,len=0; + i64 *stk=malloc(cap*sizeof(i64)); + for(i64 i=0;i<p.len;i++){ + if(p.ins[i].type==ILOOP1){ + if(len==cap){ + cap*=2; + stk=realloc(stk,cap*sizeof(i64)); + assert(stk); + } + stk[len++]=i; + } else if(p.ins[i].type==ILOOP2){ + if(len==0)die("Jm: mismatched loops"); + jm[stk[len-1]]=i; + jm[i]=stk[len-1]; + len--; + } + } + free(stk); + } + + const i64 memsize=60000,startidx=30000; + u8 *mem=calloc(memsize,1); + assert(mem); + for(i64 ip=0,mp=startidx;ip<p.len;ip++){ + switch(p.ins[ip].type){ + case IADD: mem[mp+p.ins[ip].off]+=p.ins[ip].value; break; + case ISET: mem[mp+p.ins[ip].off]=p.ins[ip].value; break; + case ISLIDE: mp+=p.ins[ip].off; break; + case IINPUT: mem[mp+p.ins[ip].off]=getchar(); break; + case IOUTPUT: putchar(mem[mp+p.ins[ip].off]); break; + case ILOOP1: if(!mem[mp+p.ins[ip].off])ip=jm[ip]; break; + case ILOOP2: if(mem[mp+p.ins[ip].off])ip=jm[ip]; break; + case IDEBUG: { + int low=0,high=memsize-1; + while(low<startidx&&mem[low]==0)low++; + while(high>startidx&&mem[high]==0)high++; + for(int i=low;i<=high;i++){ + fprintf(stderr,"%3u ",(unsigned)mem[i]); + } + fputc('\n',stderr); + break; + } + } + } + + free(jm); + free(mem); +} + +static struct program parse(const char *source,i64 length){ + struct program p=p_make(); + int offset=0; + u8 addc=0; + i64 depth=0; + for(i64 i=0;i<length;i++){ + if(strchr("+-><,.[]#",source[i])==NULL)continue; + if(source[i]=='+'){addc++; continue;} + if(source[i]=='-'){addc--; continue;} + if(addc!=0)p_append(&p,(struct ins){IADD,offset,addc}); + addc=0; + if(source[i]=='>'){offset++; continue;} + if(source[i]=='<'){offset--; continue;} + if(source[i]==','){ + p_append(&p,(struct ins){IINPUT,offset,0}); + continue; + } + if(source[i]=='.'){ + p_append(&p,(struct ins){IOUTPUT,offset,0}); + continue; + } + if(offset!=0)p_append(&p,(struct ins){ISLIDE,offset,0}); + offset=0; + if(source[i]=='['){ + depth++; + p_append(&p,(struct ins){ILOOP1,offset,0}); + continue; + } + if(source[i]==']'){ + if(depth==0)die("Parse: mismatched loops"); + depth--; + p_append(&p,(struct ins){ILOOP2,0,0}); + continue; + } + if(source[i]=='#'){ + p_append(&p,(struct ins){IDEBUG,0,0}); + continue; + } + } + return p; +} + + +int main(int argc,char **argv){ + if(argc!=2){ + die("Usage: %s <file.bf>\n",argv[0]); + } + i64 length; + char *source=readfile(argv[1],&length); + struct program p=parse(source,length); + // p_dump(p,stdout); + p_run(p); +} |