implemented cksum

src/cksum/Makefile

@@ -0,0 +1,5 @@
+OUT := cksum
+
+SRC := cksum.c
+
+include ../shared.mk

src/cksum/cksum.1

@@ -0,0 +1 @@
+\" TODO

src/cksum/cksum.c

@@ -0,0 +1,26 @@
+#include<stdint.h>
+#include<stdio.h>
+
+#define NAME "cksum (canoutils)"
+#define VERSION "0.0.1"
+#define AUTHOR "cospplredman"
+
+#include"../version_info.h"
+
+#define X(a,...) for(a)for(r=(r<<8)^(e&0xff)^__VA_ARGS__,e=0,i=31;i>23;i--)if(r&(1<<i))r^=(1<<i)|(q>>(32-i)),e^=q<<(i-24);
+
+uint32_t q=0x04c11db7,r,e;d,i=1,t,j,k,f=2;main(c,v)char**v;{
+	if(c<2)exit(1);
+	for(;++k<c;){
+		if(f&&(!strcmp(v[k], "--")|!strcmp(v[k], "-v"))){
+			if(v[k][1]=='-')f=0;
+			if(f==2){f=1;print_version();}
+			continue;
+		}
+		FILE*f=fopen(v[k],"r");
+		if(f==NULL)exit(1);
+		X(;(d=getc(f))>=0;t++,d)X(j=t;j;,(j&0xff),j>>=8)X(j=3;j--;,0)
+		if(printf("%u %d %s\n",~((r<<8)|(e&0xff)),t,v[k])<0)exit(1);
+		r=e=t=0;
+	}
+}