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Commit5ecd4e3

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committed
Binary send/receive routines for a few basic datatypes --- enough for
testing purposes.
1 parent4207d6b commit5ecd4e3

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13 files changed

+691
-184
lines changed

13 files changed

+691
-184
lines changed

‎src/backend/libpq/pqformat.c

Lines changed: 181 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -15,10 +15,16 @@
1515
* pq_getmessage, and then parsed and converted from that using the routines
1616
* in this module.
1717
*
18+
* These same routines support reading and writing of external binary formats
19+
* (typsend/typreceive routines). The conversion routines for individual
20+
* data types are exactly the same, only initialization and completion
21+
* are different.
22+
*
23+
*
1824
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
1925
* Portions Copyright (c) 1994, Regents of the University of California
2026
*
21-
*$Header: /cvsroot/pgsql/src/backend/libpq/pqformat.c,v 1.29 2003/05/08 18:16:36 tgl Exp $
27+
*$Header: /cvsroot/pgsql/src/backend/libpq/pqformat.c,v 1.30 2003/05/09 15:44:40 tgl Exp $
2228
*
2329
*-------------------------------------------------------------------------
2430
*/
@@ -28,23 +34,31 @@
2834
*pq_beginmessage - initialize StringInfo buffer
2935
*pq_sendbyte- append a raw byte to a StringInfo buffer
3036
*pq_sendint- append a binary integer to a StringInfo buffer
37+
*pq_sendint64- append a binary 8-byte int to a StringInfo buffer
3138
*pq_sendbytes- append raw data to a StringInfo buffer
32-
*pq_sendcountedtext - append a text string (with character set conversion)
39+
*pq_sendcountedtext - append a counted text string (with character set conversion)
40+
*pq_sendtext- append a text string (with conversion)
3341
*pq_sendstring- append a null-terminated text string (with conversion)
3442
*pq_endmessage- send the completed message to the frontend
3543
* Note: it is also possible to append data to the StringInfo buffer using
3644
* the regular StringInfo routines, but this is discouraged since required
3745
* character set conversion may not occur.
3846
*
47+
* typsend support (construct a bytea value containing external binary data):
48+
*pq_begintypsend - initialize StringInfo buffer
49+
*pq_endtypsend- return the completed string as a "bytea*"
50+
*
3951
* Special-case message output:
4052
*pq_puttextmessage - generate a character set-converted message in one step
4153
*pq_putemptymessage - convenience routine for message with empty body
4254
*
4355
* Message parsing after input:
4456
*pq_getmsgbyte- get a raw byte from a message buffer
4557
*pq_getmsgint- get a binary integer from a message buffer
58+
*pq_getmsgint64- get a binary 8-byte int from a message buffer
4659
*pq_getmsgbytes- get raw data from a message buffer
4760
*pq_copymsgbytes- copy raw data from a message buffer
61+
*pq_getmsgtext- get a counted text string (with conversion)
4862
*pq_getmsgstring- get a null-terminated text string (with conversion)
4963
*pq_getmsgend- verify message fully consumed
5064
*/
@@ -101,7 +115,7 @@ pq_sendbytes(StringInfo buf, const char *data, int datalen)
101115
}
102116

103117
/* --------------------------------
104-
*pq_sendcountedtext - append a text string (with character set conversion)
118+
*pq_sendcountedtext - append acountedtext string (with character set conversion)
105119
*
106120
* The data sent to the frontend by this routine is a 4-byte count field
107121
* followed by the string. The count includes itself or not, as per the
@@ -132,6 +146,34 @@ pq_sendcountedtext(StringInfo buf, const char *str, int slen,
132146
}
133147
}
134148

149+
/* --------------------------------
150+
*pq_sendtext- append a text string (with conversion)
151+
*
152+
* The passed text string need not be null-terminated, and the data sent
153+
* to the frontend isn't either. Note that this is not actually useful
154+
* for direct frontend transmissions, since there'd be no way for the
155+
* frontend to determine the string length. But it is useful for binary
156+
* format conversions.
157+
* --------------------------------
158+
*/
159+
void
160+
pq_sendtext(StringInfobuf,constchar*str,intslen)
161+
{
162+
char*p;
163+
164+
p= (char*)pg_server_to_client((unsignedchar*)str,slen);
165+
if (p!=str)/* actual conversion has been done? */
166+
{
167+
slen=strlen(p);
168+
appendBinaryStringInfo(buf,p,slen);
169+
pfree(p);
170+
}
171+
else
172+
{
173+
appendBinaryStringInfo(buf,str,slen);
174+
}
175+
}
176+
135177
/* --------------------------------
136178
*pq_sendstring- append a null-terminated text string (with conversion)
137179
*
@@ -152,9 +194,11 @@ pq_sendstring(StringInfo buf, const char *str)
152194
slen=strlen(p);
153195
appendBinaryStringInfo(buf,p,slen+1);
154196
pfree(p);
155-
return;
156197
}
157-
appendBinaryStringInfo(buf,str,slen+1);
198+
else
199+
{
200+
appendBinaryStringInfo(buf,str,slen+1);
201+
}
158202
}
159203

160204
/* --------------------------------
@@ -188,6 +232,35 @@ pq_sendint(StringInfo buf, int i, int b)
188232
}
189233
}
190234

235+
/* --------------------------------
236+
*pq_sendint64- append a binary 8-byte int to a StringInfo buffer
237+
*
238+
* It is tempting to merge this with pq_sendint, but we'd have to make the
239+
* argument int64 for all data widths --- that could be a big performance
240+
* hit on machines where int64 isn't efficient.
241+
* --------------------------------
242+
*/
243+
void
244+
pq_sendint64(StringInfobuf,int64i)
245+
{
246+
uint32n32;
247+
248+
/* High order half first, since we're doing MSB-first */
249+
#ifdefINT64_IS_BUSTED
250+
/* don't try a right shift of 32 on a 32-bit word */
251+
n32= (i<0) ?-1 :0;
252+
#else
253+
n32= (uint32) (i >>32);
254+
#endif
255+
n32=htonl(n32);
256+
appendBinaryStringInfo(buf, (char*)&n32,4);
257+
258+
/* Now the low order half */
259+
n32= (uint32)i;
260+
n32=htonl(n32);
261+
appendBinaryStringInfo(buf, (char*)&n32,4);
262+
}
263+
191264
/* --------------------------------
192265
*pq_endmessage- send the completed message to the frontend
193266
*
@@ -205,6 +278,44 @@ pq_endmessage(StringInfo buf)
205278
buf->data=NULL;
206279
}
207280

281+
282+
/* --------------------------------
283+
*pq_begintypsend- initialize for constructing a bytea result
284+
* --------------------------------
285+
*/
286+
void
287+
pq_begintypsend(StringInfobuf)
288+
{
289+
initStringInfo(buf);
290+
/* Reserve four bytes for the bytea length word */
291+
appendStringInfoCharMacro(buf,'\0');
292+
appendStringInfoCharMacro(buf,'\0');
293+
appendStringInfoCharMacro(buf,'\0');
294+
appendStringInfoCharMacro(buf,'\0');
295+
}
296+
297+
/* --------------------------------
298+
*pq_endtypsend- finish constructing a bytea result
299+
*
300+
* The data buffer is returned as the palloc'd bytea value. (We expect
301+
* that it will be suitably aligned for this because it has been palloc'd.)
302+
* We assume the StringInfoData is just a local variable in the caller and
303+
* need not be pfree'd.
304+
* --------------------------------
305+
*/
306+
bytea*
307+
pq_endtypsend(StringInfobuf)
308+
{
309+
bytea*result= (bytea*)buf->data;
310+
311+
/* Insert correct length into bytea length word */
312+
Assert(buf->len >=VARHDRSZ);
313+
VARATT_SIZEP(result)=buf->len;
314+
315+
returnresult;
316+
}
317+
318+
208319
/* --------------------------------
209320
*pq_puttextmessage - generate a character set-converted message in one step
210321
*
@@ -289,6 +400,38 @@ pq_getmsgint(StringInfo msg, int b)
289400
returnresult;
290401
}
291402

403+
/* --------------------------------
404+
*pq_getmsgint64- get a binary 8-byte int from a message buffer
405+
*
406+
* It is tempting to merge this with pq_getmsgint, but we'd have to make the
407+
* result int64 for all data widths --- that could be a big performance
408+
* hit on machines where int64 isn't efficient.
409+
* --------------------------------
410+
*/
411+
int64
412+
pq_getmsgint64(StringInfomsg)
413+
{
414+
int64result;
415+
uint32h32;
416+
uint32l32;
417+
418+
pq_copymsgbytes(msg, (char*)&h32,4);
419+
pq_copymsgbytes(msg, (char*)&l32,4);
420+
h32=ntohl(h32);
421+
l32=ntohl(l32);
422+
423+
#ifdefINT64_IS_BUSTED
424+
/* just lose the high half */
425+
result=l32;
426+
#else
427+
result=h32;
428+
result <<=32;
429+
result |=l32;
430+
#endif
431+
432+
returnresult;
433+
}
434+
292435
/* --------------------------------
293436
*pq_getmsgbytes- get raw data from a message buffer
294437
*
@@ -323,6 +466,39 @@ pq_copymsgbytes(StringInfo msg, char *buf, int datalen)
323466
msg->cursor+=datalen;
324467
}
325468

469+
/* --------------------------------
470+
*pq_getmsgtext- get a counted text string (with conversion)
471+
*
472+
*Always returns a pointer to a freshly palloc'd result.
473+
*The result has a trailing null, *and* we return its strlen in *nbytes.
474+
* --------------------------------
475+
*/
476+
char*
477+
pq_getmsgtext(StringInfomsg,intrawbytes,int*nbytes)
478+
{
479+
char*str;
480+
char*p;
481+
482+
if (rawbytes<0||rawbytes> (msg->len-msg->cursor))
483+
elog(ERROR,"pq_getmsgtext: insufficient data left in message");
484+
str=&msg->data[msg->cursor];
485+
msg->cursor+=rawbytes;
486+
487+
p= (char*)pg_client_to_server((unsignedchar*)str,rawbytes);
488+
if (p!=str)/* actual conversion has been done? */
489+
{
490+
*nbytes=strlen(p);
491+
}
492+
else
493+
{
494+
p= (char*)palloc(rawbytes+1);
495+
memcpy(p,str,rawbytes);
496+
p[rawbytes]='\0';
497+
*nbytes=rawbytes;
498+
}
499+
returnp;
500+
}
501+
326502
/* --------------------------------
327503
*pq_getmsgstring- get a null-terminated text string (with conversion)
328504
*

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