Add missing encode file.

1 files changed, 346 insertions, 0 deletions

diff --git a/src/backend/utils/adt/encode.c b/src/backend/utils/adt/encode.c
new file mode 100644
index 00000000000..89ba357aa57
--- /dev/null
+++ b/src/backend/utils/adt/encode.c
@@ -0,0 +1,346 @@
+/*-------------------------------------------------------------------------
+ *
+ * encode.c
+ *	  Various data encoding/decoding things.
+ *
+ * Copyright (c) 2001 PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/encode.c,v 1.1 2001/07/12 14:05:31 momjian Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <ctype.h>
+#include "utils/builtins.h"
+
+
+struct pg_encoding
+{
+	unsigned		(*encode_len) (unsigned dlen);
+	unsigned		(*decode_len) (unsigned dlen);
+	unsigned		(*encode) (const uint8 *data, unsigned dlen, uint8 *res);
+	unsigned		(*decode) (const uint8 *data, unsigned dlen, uint8 *res);
+};
+
+static struct pg_encoding * pg_find_encoding(const char *name);
+
+/*
+ * SQL functions.
+ */
+
+Datum
+binary_encode(PG_FUNCTION_ARGS)
+{
+	bytea	   *data = PG_GETARG_BYTEA_P(0);
+	Datum		name = PG_GETARG_DATUM(1);
+	text	   *result;
+	char	   *namebuf;
+	int		namelen, datalen, resultlen, res;
+	struct pg_encoding *enc;
+
+	datalen = VARSIZE(data) - VARHDRSZ;
+	namelen = VARSIZE(name) - VARHDRSZ;
+
+	namebuf = (char *)DirectFunctionCall1(textout, name);
+
+	enc = pg_find_encoding(namebuf);
+	if (enc == NULL)
+		elog(ERROR, "No such encoding");
+
+	resultlen = enc->encode_len(datalen);
+	result = palloc(VARHDRSZ + resultlen);
+
+	res = enc->encode(VARDATA(data), datalen, VARDATA(result));
+	if (res > resultlen)
+		elog(ERROR, "Overflow - encode estimate too small");
+
+	VARATT_SIZEP(result) = VARHDRSZ + res;
+
+	PG_RETURN_TEXT_P(result);
+}
+
+Datum
+binary_decode(PG_FUNCTION_ARGS)
+{
+	text	   *data = PG_GETARG_TEXT_P(0);
+	Datum		name = PG_GETARG_DATUM(1);
+	bytea	   *result;
+	char		*namebuf;
+	int			namelen, datalen, resultlen, res;
+	struct pg_encoding *enc;
+
+	datalen = VARSIZE(data) - VARHDRSZ;
+	namelen = VARSIZE(name) - VARHDRSZ;
+
+	namebuf = (char *)DirectFunctionCall1(textout, name);
+
+	enc = pg_find_encoding(namebuf);
+	if (enc == NULL)
+		elog(ERROR, "No such encoding");
+
+	resultlen = enc->decode_len(datalen);
+	result = palloc(VARHDRSZ + resultlen);
+
+	res = enc->decode(VARDATA(data), datalen, VARDATA(result));
+	if (res > resultlen)
+		elog(ERROR, "Overflow - decode estimate too small");
+
+	VARATT_SIZEP(result) = VARHDRSZ + res;
+
+	PG_RETURN_BYTEA_P(result);
+}
+
+
+/*
+ * HEX
+ */
+
+static const char *hextbl = "0123456789abcdef";
+
+static const int8 hexlookup[128] = {
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1,
+	-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+};
+
+static unsigned
+hex_encode(const uint8 * src, unsigned len, uint8 * dst)
+{
+	const uint8	   *end = src + len;
+
+	while (src < end)
+	{
+		*dst++ = hextbl[(*src >> 4) & 0xF];
+		*dst++ = hextbl[*src & 0xF];
+		src++;
+	}
+	return len * 2;
+}
+
+static uint8
+get_hex(unsigned c)
+{
+	int		res = -1;
+
+	if (c > 0 && c < 127)
+		res = hexlookup[c];
+
+	if (res < 0)
+		elog(ERROR, "Bad hex code: '%c'", c);
+
+	return (uint8)res;
+}
+
+static unsigned
+hex_decode(const uint8 * src, unsigned len, uint8 * dst)
+{
+	const uint8 *s,
+			   *srcend;
+	uint8		v1,
+				v2,
+			   *p = dst;
+
+	srcend = src + len;
+	s = src;
+	p = dst;
+	while (s < srcend)
+	{
+		if (*s == ' ' || *s == '\n' || *s == '\t' || *s == '\r')
+		{
+			s++;
+			continue;
+		}
+		v1 = get_hex(*s++) << 4;
+		if (s >= srcend)
+			elog(ERROR, "hex_decode: invalid data");
+		v2 = get_hex(*s++);
+		*p++ = v1 | v2;
+	}
+
+	return p - dst;
+}
+
+static unsigned
+hex_enc_len(unsigned srclen)
+{
+	return srclen << 1;
+}
+
+static unsigned
+hex_dec_len(unsigned srclen)
+{
+	return srclen >> 1;
+}
+
+/*
+ * BASE64
+ */
+
+static const unsigned char _base64[] =
+"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+static const int8 b64lookup[128] = {
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
+	52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
+	-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
+	15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
+	-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+	41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
+};
+
+static unsigned
+b64_encode(const uint8 * src, unsigned len, uint8 * dst)
+{
+	uint8	   *p,
+			   *lend = dst + 76;
+	const uint8 *s,
+			   *end = src + len;
+	int			pos = 2;
+	uint32		buf = 0;
+
+	s = src;
+	p = dst;
+
+	while (s < end)
+	{
+		buf |= *s << (pos << 3);
+		pos--;
+		s++;
+
+		/* write it out */
+		if (pos < 0)
+		{
+			*p++ = _base64[(buf >> 18) & 0x3f];
+			*p++ = _base64[(buf >> 12) & 0x3f];
+			*p++ = _base64[(buf >> 6) & 0x3f];
+			*p++ = _base64[buf & 0x3f];
+
+			pos = 2;
+			buf = 0;
+		}
+		if (p >= lend)
+		{
+			*p++ = '\n';
+			lend = p + 76;
+		}
+	}
+	if (pos != 2)
+	{
+		*p++ = _base64[(buf >> 18) & 0x3f];
+		*p++ = _base64[(buf >> 12) & 0x3f];
+		*p++ = (pos == 0) ? _base64[(buf >> 6) & 0x3f] : '=';
+		*p++ = '=';
+	}
+
+	return p - dst;
+}
+
+static unsigned
+b64_decode(const uint8 * src, unsigned len, uint8 * dst)
+{
+	const char	   *srcend = src + len,
+			   *s = src;
+	uint8	   *p = dst;
+	unsigned	c;
+	int			b = 0;
+	uint32		buf = 0;
+	int			pos = 0,
+				end = 0;
+
+	while (s < srcend)
+	{
+		c = *s++;
+
+		if (c == ' ' || c == '\t' || c == '\n' || c == '\r')
+			continue;
+
+		if (c == '=')
+		{
+			/* end sequence */
+			if (!end)
+			{
+				if (pos == 2)
+					end = 1;
+				else if (pos == 3)
+					end = 2;
+				else
+					elog(ERROR, "base64: unexpected '='");
+			}
+			b = 0;
+		}
+		else {
+			b = -1;
+			if (c > 0 && c < 127)
+				b = b64lookup[c];
+			if (b < 0)
+				elog(ERROR, "base64: Invalid symbol");
+		}
+		/* add it to buffer */
+		buf = (buf << 6) + b;
+		pos++;
+		if (pos == 4)
+		{
+			*p++ = (buf >> 16) & 255;
+			if (end == 0 || end > 1)
+				*p++ = (buf >> 8) & 255;
+			if (end == 0 || end > 2)
+				*p++ = buf & 255;
+			buf = 0;
+			pos = 0;
+		}
+	}
+
+	if (pos != 0)
+		elog(ERROR, "base64: invalid end sequence");
+
+	return p - dst;
+}
+
+
+static unsigned
+b64_enc_len(unsigned srclen)
+{
+	/* 3 bytes will be converted to 4, linefeed after 76 chars */
+	return (srclen + 2) * 4 / 3 + srclen / (76 * 3 / 4);
+}
+
+static unsigned
+b64_dec_len(unsigned srclen)
+{
+	return (srclen * 3) >> 2;
+}
+
+/*
+ * Common
+ */
+
+static struct {
+	const char *name;
+	struct pg_encoding enc;
+} enclist[] = {
+	{"hex", { hex_enc_len, hex_dec_len, hex_encode, hex_decode }},
+	{"base64", { b64_enc_len, b64_dec_len, b64_encode, b64_decode }},
+	{NULL, { NULL, NULL, NULL, NULL } }
+};
+
+static struct pg_encoding *
+pg_find_encoding(const char *name)
+{
+	int i;
+
+	for (i = 0; enclist[i].name; i++)
+		if (!strcasecmp(enclist[i].name, name))
+			return &enclist[i].enc;
+
+	return NULL;
+}