add base64 scanner

t.c

@@ -17,30 +17,18 @@
      __asm__ __volatile__ ("rdtsc" : "=a" (low) : : "edx")
 
 int main(int argc,char* argv[]) {
-  unsigned long size;
+  char buf[100];
-  char* buf=mmap_read(argv[1],&size);
+  char buf2[100];
-  if (buf) {
+  unsigned int len,len2;
-    const char* c=buf;
+  buf[fmt_base64(buf,"foo:bar",7)]=0;
-    const char* max=buf+size;
+  buffer_puts(buffer_1,buf);
-    while (c<max) {
+  buffer_putsflush(buffer_1,"\n");
-      char tmp[100];
+  if ((buf[len2=scan_base64(buf,buf2,&len)])!=0) {
-      unsigned int scanned;
+    buffer_putsflush(buffer_2,"parse error!\n");
-      unsigned int x=scan_uuencoded(c,tmp,&scanned);
+    return 1;
-      if (!x) {
-	if (!strncmp(c,"end\n",4))
-	  return 0;
-	else {
-parseerror:
-	  buffer_putsflush(buffer_2,"parse error!\n");
-	  exit(1);
-	}
-      }
-      write(1,tmp,scanned);
-      c+=x;
-      if (*c!='\n') goto parseerror;
-      ++c;
-    }
   }
+  buffer_put(buffer_1,buf2,len2);
+  buffer_putsflush(buffer_1,"\n");
   return 0;
 #if 0
   unsigned long size;

textcode/fmt_base64.c

@@ -2,10 +2,6 @@
 #include "textcode.h"
 #include "haveinline.h"
 
-static inline unsigned int enc(unsigned char x) {
-  return ((x-1)&077)+'!';
-}
-
 unsigned int fmt_base64(char* dest,const char* src,unsigned int len) {
   register const unsigned char* s=(const unsigned char*) src;
   unsigned short bits=0,temp=0;

textcode/scan_base64.c

@@ -0,0 +1,34 @@
+#include "textcode.h"
+#include "haveinline.h"
+
+static inline int dec(unsigned char x) {
+  if (x>='A' && x<='Z') return x-'A';
+  if (x>='a' && x<='z') return x-'a'+26;
+  if (x>='0' && x<='9') return x-'0'+26+26;
+  switch (x) {
+  case '+': return 62;
+  case '/': return 63;
+  default: return -1;
+  }
+}
+
+unsigned int scan_base64(const char *src,char *dest,unsigned int *destlen) {
+  unsigned short tmp=0,bits=0;
+  register const unsigned char* s=(const unsigned char*) src;
+  const char* orig=dest;
+  for (;;) {
+    int a=dec(*s);
+    if (a<0) {
+      while (*s=='=') ++s;
+      break;
+    }
+    tmp=(tmp<<6)|a; bits+=6;
+    ++s;
+    if (bits>=8) {
+      *dest=(tmp>>(bits-=8));
+      ++dest;
+    }
+  }
+  *destlen=dest-orig;
+  return (const char*)s-src;
+}

textcode/scan_uuencoded.c

@@ -1,5 +1,4 @@
 #include "textcode.h"
-#include "haveinline.h"
 
 unsigned int scan_uuencoded(const char *src,char *dest,unsigned int *destlen) {
   unsigned int len;