Index: /trunk/Ohana/src/kapa2/doc/base85.c
===================================================================
--- /trunk/Ohana/src/kapa2/doc/base85.c	(revision 41328)
+++ /trunk/Ohana/src/kapa2/doc/base85.c	(revision 41328)
@@ -0,0 +1,190 @@
+/* base85.c : encode numbers using two different techniques for Base-85 
+ * PUBLIC DOMAIN - Jon Mayo - September 10, 2008 */
+#include <assert.h>
+#include <stdio.h>
+#include <limits.h>
+#include <string.h>
+
+/* define this to use PDF/adobe Ascii85 encoding
+ * default is to use an encoding derived from RFC1924, except 32-bits at a time instead of 128-bits
+ * yes, I realize that RFC1924 is a joke RFC
+ */
+#define USE_ASCII85
+
+#define NR(x) (sizeof(x)/sizeof*(x))
+
+#define BASETYPE unsigned int
+
+#define BASE85_DIGITS	5	 /* log85 (2^32) is 4.9926740807112 */
+#ifndef USE_ASCII85
+/* rfc1924 :) */
+static const unsigned char base85[85] =  "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{|}~";
+#else
+/* ascii85 (adobe) */
+static const unsigned char base85[85] =  "!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstu";
+#endif
+static signed char decode_table[UCHAR_MAX];
+
+/* create a look up table suitable for convering characters to base85 digits */
+static void base85_init(void) {
+	unsigned char ch;
+
+	assert((sizeof base85 == 85) && (base85[84] != 0)); /* make sure the array is exactly the right size */
+
+	for(ch=0;ch<UCHAR_MAX;ch++) {
+		decode_table[ch]=-1;
+	}
+	for(ch=0;ch<85;ch++) {
+		decode_table[base85[ch]]=ch;
+	}
+}
+
+/* convert a list of 32-bit values into a base85 string.
+ * if you wish to encode 8-bit values, load them into 32-bit values in Big Endian order
+ * example:
+ *   input: "Lion"
+ *   ascii85: 9PJE_
+ *   base85: !aflO
+ */
+static int base85_encode(char *out, size_t max, const BASETYPE *data, size_t count) {
+	size_t i;
+	BASETYPE n;
+
+	fprintf (stderr, "data[0]: %x, %d\n", data[0], (int)(data[0] % 85));
+
+	while(count) {
+		if(max<1) return 0; /* failure */
+		n=*data++;
+		count--;
+#ifndef USE_ASCII85
+		/* rfc1924 :) */
+		for(i=0;max>0 && i<BASE85_DIGITS;i++) {
+			*out++=base85[n%85];
+			max--;
+			n/=85;
+		}
+#else
+		/* Ascii85 (adobe) */
+		if(n==0) {
+			*out++='z'; /* this is a special zero character */
+			max--;
+		} else {
+			if(max<5) return 0; /* no room */
+			for(i=BASE85_DIGITS;i--;) {
+				out[i]=base85[n%85];
+				n/=85;
+			}
+			max-=5;
+			out+=5;
+		}
+#endif
+	}
+	*out=0;
+	return 1; /* success */
+}
+
+/* convert a base85 string into a list of 32-bit values
+ * treats string as if it were padded with 0s */
+static int base85_decode(BASETYPE *out, size_t out_count, const char *in) {
+	unsigned in_count;
+	BASETYPE n, k;
+
+	if(*in==0) return 0; /* nothing to decode */
+	while(*in) {
+		if(out_count<=0) return 0; /* failure - not enough space in destination */
+		n=0;
+#ifndef USE_ASCII85
+		/* rfc1924 :) */
+		for(in_count=0,k=1;*in && in_count<BASE85_DIGITS;in_count++) {
+			signed d; /* digit */
+			d=decode_table[(unsigned char)*in++];
+			if(d<0) return 0; /* failure - invalid character */
+			n+=k*d;
+			k*=85;
+		}
+#else
+		/* Ascii85 (adobe) */
+		/* 'z' is a special way to encode 4 bytes of 0s */
+		if(*in=='z') {
+			in++;
+		} else for(in_count=0,k=1;*in && in_count<BASE85_DIGITS;in_count++) {
+			signed d; /* digit */
+			d=decode_table[(unsigned char)*in++];
+			if(d<0)  return 0; /* failure - invalid character */
+			n=n*85+d;
+		}
+
+#endif
+		*out++=n;
+		out_count--;
+	}
+	return 1; /* success */
+}
+
+// ~0UL is long long, so probably not valid
+static int base85_test(int verbose) {
+	const BASETYPE testdata[] = {
+		0x4c696f6e, 0x0ddba11, 0xba5eba11, 0xbeef, 0xcafe, 0xb00b, 0xdeadbea7, 0xdefec8, 0xbedabb1e, 0xf01dab1e, 0xf005ba11, 0xb01dface,
+		0x5ca1ab1e, 0xcab005e, 0xdeadfa11, 0x1eadf007, 0xdefea7, 0, 1, (unsigned)-8, (unsigned)-9, 0x4d616e20, 0x206e614d, 0xffffffff, ~0UL,
+	};
+	char buf[5*NR(testdata)+1];
+	BASETYPE testout[NR(testdata)];
+	size_t i;
+
+	base85_init();
+
+	if(!base85_encode(buf, sizeof buf, testdata, NR(testdata))) return 0;
+
+	if(verbose) printf("base85 = %s\n", buf);
+	if(verbose) fwrite ((char *) testdata, 1, sizeof(testdata), stdout);
+
+	if(!base85_decode(testout, NR(testout), buf)) return 0;
+
+	for(i=0;i<NR(testdata);i++) {
+		if(verbose) {
+			printf("in[%zu] = %u 0x%x\n", i, testdata[i], testdata[i]);
+			printf("out[%zu] = %u 0x%x\n", i, testout[i], testout[i]);
+		}
+		if(testdata[i]!=testout[i]) {
+			return 0; /* failure */
+		}
+	}
+
+	if(!base85_decode(&testout[0], 1, "Ll100")) return 0;
+	if(!base85_decode(&testout[1], 1, "Ll1")) return 0;
+	if(!base85_decode(&testout[2], 1, "00Ll1")) return 0;
+	for(i=0;i<3;i++) {
+		if(verbose) printf("misc[%zu] = %u 0x%x\n", i, testout[i], testout[i]);
+	}
+	
+	return 1; /* pass */
+}
+
+int main(void) {
+  if(base85_test(1)) {
+    printf("base85 passed\n");
+  } else {
+    printf("base85 failed\n");
+  }
+
+  // char quote[] = "Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.";
+  // int Nout = 5*((int)(strlen(quote)/4));
+
+  // char quote[16];
+  // memset (quote, 0, 16);
+  // strcpy (quote, "noiL");
+
+  // fprintf (stderr, "sizeof input %d\n", (int) sizeof(input));
+
+  char quote[5];
+  strcpy (quote, "noiL");
+
+  int Nout = 5;
+  char output[Nout];
+
+  base85_init();
+  if (!base85_encode (output, Nout, (BASETYPE *) quote, 1)) { fprintf (stderr, "failure\n"); }
+  fwrite (output, 1, Nout, stdout);
+
+  return 0;
+}