/*
* Attempt to read an Error or Notice response message.
* This is possible in several places, so we break it out as a subroutine.
* Entry: 'E' or 'N' message type has already been consumed.
* Exit: returns 0 if successfully consumed message.
* returns EOF if not enough data.
*/
static int
pqGetErrorNotice2(PGconn *conn, bool isError)
{
PGresult *res = NULL;
PQExpBufferData workBuf;
char *startp;
char *splitp;
/*
* Since the message might be pretty long, we create a temporary
* PQExpBuffer rather than using conn->workBuffer. workBuffer is intended
* for stuff that is expected to be short.
*/
initPQExpBuffer(&workBuf);
if (pqGets(&workBuf, conn))
goto failure;
/*
* Make a PGresult to hold the message. We temporarily lie about the
* result status, so that PQmakeEmptyPGresult doesn't uselessly copy
* conn->errorMessage.
*
* NB: This allocation can fail, if you run out of memory. The rest of the
* function handles that gracefully, and we still try to set the error
* message as the connection's error message.
*/
res = PQmakeEmptyPGresult(conn, PGRES_EMPTY_QUERY);
if (res)
{
res->resultStatus = isError ? PGRES_FATAL_ERROR : PGRES_NONFATAL_ERROR;
res->errMsg = pqResultStrdup(res, workBuf.data);
}
/*
* Break the message into fields. We can't do very much here, but we can
* split the severity code off, and remove trailing newlines. Also, we use
* the heuristic that the primary message extends only to the first
* newline --- anything after that is detail message. (In some cases it'd
* be better classed as hint, but we can hardly be expected to guess that
* here.)
*/
while (workBuf.len > 0 && workBuf.data[workBuf.len - 1] == '\n')
workBuf.data[--workBuf.len] = '\0';
splitp = strstr(workBuf.data, ": ");
if (splitp)
{
/* what comes before the colon is severity */
*splitp = '\0';
pqSaveMessageField(res, PG_DIAG_SEVERITY, workBuf.data);
startp = splitp + 3;
}
else
{
/* can't find a colon? oh well... */
startp = workBuf.data;
}
splitp = strchr(startp, '\n');
if (splitp)
{
/* what comes before the newline is primary message */
*splitp++ = '\0';
pqSaveMessageField(res, PG_DIAG_MESSAGE_PRIMARY, startp);
/* the rest is detail; strip any leading whitespace */
while (*splitp && isspace((unsigned char) *splitp))
splitp++;
pqSaveMessageField(res, PG_DIAG_MESSAGE_DETAIL, splitp);
}
else
{
/* single-line message, so all primary */
pqSaveMessageField(res, PG_DIAG_MESSAGE_PRIMARY, startp);
}
/*
* Either save error as current async result, or just emit the notice.
* Also, if it's an error and we were in a transaction block, assume the
* server has now gone to error-in-transaction state.
*/
if (isError)
{
pqClearAsyncResult(conn);
conn->result = res;
resetPQExpBuffer(&conn->errorMessage);
if (res && !PQExpBufferDataBroken(workBuf) && res->errMsg)
appendPQExpBufferStr(&conn->errorMessage, res->errMsg);
else
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory"));
if (conn->xactStatus == PQTRANS_INTRANS)
conn->xactStatus = PQTRANS_INERROR;
}
else
{
if (res)
{
if (res->noticeHooks.noticeRec != NULL)
(*res->noticeHooks.noticeRec) (res->noticeHooks.noticeRecArg, res);
PQclear(res);
}
}
termPQExpBuffer(&workBuf);
return 0;
failure:
if (res)
PQclear(res);
termPQExpBuffer(&workBuf);
return EOF;
}
/*
* parseInput subroutine to read a 'B' or 'D' (row data) message.
* We fill rowbuf with column pointers and then call the row processor.
* Returns: 0 if completed message, EOF if error or not enough data
* received yet.
*
* Note that if we run out of data, we have to suspend and reprocess
* the message after more data is received. Otherwise, conn->inStart
* must get advanced past the processed data.
*/
static int
getAnotherTuple(PGconn *conn, bool binary)
{
PGresult *result = conn->result;
int nfields = result->numAttributes;
const char *errmsg;
PGdataValue *rowbuf;
/* the backend sends us a bitmap of which attributes are null */
char std_bitmap[64]; /* used unless it doesn't fit */
char *bitmap = std_bitmap;
int i;
size_t nbytes; /* the number of bytes in bitmap */
char bmap; /* One byte of the bitmap */
int bitmap_index; /* Its index */
int bitcnt; /* number of bits examined in current byte */
int vlen; /* length of the current field value */
/* Resize row buffer if needed */
rowbuf = conn->rowBuf;
if (nfields > conn->rowBufLen)
{
rowbuf = (PGdataValue *) realloc(rowbuf,
nfields * sizeof(PGdataValue));
if (!rowbuf)
{
errmsg = NULL; /* means "out of memory", see below */
goto advance_and_error;
}
conn->rowBuf = rowbuf;
conn->rowBufLen = nfields;
}
/* Save format specifier */
result->binary = binary;
/*
* If it's binary, fix the column format indicators. We assume the
* backend will consistently send either B or D, not a mix.
*/
if (binary)
{
for (i = 0; i < nfields; i++)
result->attDescs[i].format = 1;
}
/* Get the null-value bitmap */
nbytes = (nfields + BITS_PER_BYTE - 1) / BITS_PER_BYTE;
/* malloc() only for unusually large field counts... */
if (nbytes > sizeof(std_bitmap))
{
bitmap = (char *) malloc(nbytes);
if (!bitmap)
{
errmsg = NULL; /* means "out of memory", see below */
goto advance_and_error;
}
}
if (pqGetnchar(bitmap, nbytes, conn))
goto EOFexit;
/* Scan the fields */
bitmap_index = 0;
bmap = bitmap[bitmap_index];
bitcnt = 0;
for (i = 0; i < nfields; i++)
{
/* get the value length */
if (!(bmap & 0200))
vlen = NULL_LEN;
else if (pqGetInt(&vlen, 4, conn))
goto EOFexit;
else
{
if (!binary)
vlen = vlen - 4;
if (vlen < 0)
vlen = 0;
}
rowbuf[i].len = vlen;
/*
* rowbuf[i].value always points to the next address in the data
* buffer even if the value is NULL. This allows row processors to
* estimate data sizes more easily.
*/
rowbuf[i].value = conn->inBuffer + conn->inCursor;
/* Skip over the data value */
if (vlen > 0)
{
if (pqSkipnchar(vlen, conn))
goto EOFexit;
}
/* advance the bitmap stuff */
bitcnt++;
if (bitcnt == BITS_PER_BYTE)
{
bitmap_index++;
bmap = bitmap[bitmap_index];
bitcnt = 0;
}
else
bmap <<= 1;
}
/* Release bitmap now if we allocated it */
if (bitmap != std_bitmap)
free(bitmap);
bitmap = NULL;
/* Advance inStart to show that the "D" message has been processed. */
conn->inStart = conn->inCursor;
/* Process the collected row */
errmsg = NULL;
if (pqRowProcessor(conn, &errmsg))
return 0; /* normal, successful exit */
goto set_error_result; /* pqRowProcessor failed, report it */
advance_and_error:
/*
* Discard the failed message. Unfortunately we don't know for sure where
* the end is, so just throw away everything in the input buffer. This is
* not very desirable but it's the best we can do in protocol v2.
*/
conn->inStart = conn->inEnd;
set_error_result:
/*
* Replace partially constructed result with an error result. First
* discard the old result to try to win back some memory.
*/
pqClearAsyncResult(conn);
/*
* If preceding code didn't provide an error message, assume "out of
* memory" was meant. The advantage of having this special case is that
* freeing the old result first greatly improves the odds that gettext()
* will succeed in providing a translation.
*/
if (!errmsg)
errmsg = libpq_gettext("out of memory for query result");
printfPQExpBuffer(&conn->errorMessage, "%s\n", errmsg);
/*
* XXX: if PQmakeEmptyPGresult() fails, there's probably not much we can
* do to recover...
*/
conn->result = PQmakeEmptyPGresult(conn, PGRES_FATAL_ERROR);
conn->asyncStatus = PGASYNC_READY;
EOFexit:
if (bitmap != NULL && bitmap != std_bitmap)
free(bitmap);
return EOF;
}
/*
* parseInput subroutine to read a 'T' (row descriptions) message.
* We build a PGresult structure containing the attribute data.
* Returns: 0 if completed message, EOF if error or not enough data
* received yet.
*
* Note that if we run out of data, we have to suspend and reprocess
* the message after more data is received. Otherwise, conn->inStart
* must get advanced past the processed data.
*/
static int
getRowDescriptions(PGconn *conn)
{
PGresult *result;
int nfields;
const char *errmsg;
int i;
result = PQmakeEmptyPGresult(conn, PGRES_TUPLES_OK);
if (!result)
{
errmsg = NULL; /* means "out of memory", see below */
goto advance_and_error;
}
/* parseInput already read the 'T' label. */
/* the next two bytes are the number of fields */
if (pqGetInt(&(result->numAttributes), 2, conn))
goto EOFexit;
nfields = result->numAttributes;
/* allocate space for the attribute descriptors */
if (nfields > 0)
{
result->attDescs = (PGresAttDesc *)
pqResultAlloc(result, nfields * sizeof(PGresAttDesc), TRUE);
if (!result->attDescs)
{
errmsg = NULL; /* means "out of memory", see below */
goto advance_and_error;
}
MemSet(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
}
/* get type info */
for (i = 0; i < nfields; i++)
{
int typid;
int typlen;
int atttypmod;
if (pqGets(&conn->workBuffer, conn) ||
pqGetInt(&typid, 4, conn) ||
pqGetInt(&typlen, 2, conn) ||
pqGetInt(&atttypmod, 4, conn))
goto EOFexit;
/*
* Since pqGetInt treats 2-byte integers as unsigned, we need to
* coerce the result to signed form.
*/
typlen = (int) ((int16) typlen);
result->attDescs[i].name = pqResultStrdup(result,
conn->workBuffer.data);
if (!result->attDescs[i].name)
{
errmsg = NULL; /* means "out of memory", see below */
goto advance_and_error;
}
result->attDescs[i].tableid = 0;
result->attDescs[i].columnid = 0;
result->attDescs[i].format = 0;
result->attDescs[i].typid = typid;
result->attDescs[i].typlen = typlen;
result->attDescs[i].atttypmod = atttypmod;
}
/* Success! */
conn->result = result;
/* Advance inStart to show that the "T" message has been processed. */
conn->inStart = conn->inCursor;
/*
* We could perform additional setup for the new result set here, but for
* now there's nothing else to do.
*/
/* And we're done. */
return 0;
advance_and_error:
/*
* Discard the failed message. Unfortunately we don't know for sure where
* the end is, so just throw away everything in the input buffer. This is
* not very desirable but it's the best we can do in protocol v2.
*/
conn->inStart = conn->inEnd;
/*
* Replace partially constructed result with an error result. First
* discard the old result to try to win back some memory.
*/
pqClearAsyncResult(conn);
/*
* If preceding code didn't provide an error message, assume "out of
* memory" was meant. The advantage of having this special case is that
* freeing the old result first greatly improves the odds that gettext()
* will succeed in providing a translation.
*/
if (!errmsg)
errmsg = libpq_gettext("out of memory for query result");
printfPQExpBuffer(&conn->errorMessage, "%s\n", errmsg);
/*
* XXX: if PQmakeEmptyPGresult() fails, there's probably not much we can
* do to recover...
*/
conn->result = PQmakeEmptyPGresult(conn, PGRES_FATAL_ERROR);
conn->asyncStatus = PGASYNC_READY;
EOFexit:
if (result && result != conn->result)
PQclear(result);
return EOF;
}
/*
* Attempt to read an Error or Notice response message.
* This is possible in several places, so we break it out as a subroutine.
* Entry: 'E' or 'N' message type and length have already been consumed.
* Exit: returns 0 if successfully consumed message.
* returns EOF if not enough data.
*/
int
pqGetErrorNotice3(PGconn *conn, bool isError)
{
PGresult *res = NULL;
PQExpBufferData workBuf;
char id;
const char *val;
const char *querytext = NULL;
int querypos = 0;
/*
* Since the fields might be pretty long, we create a temporary
* PQExpBuffer rather than using conn->workBuffer. workBuffer is intended
* for stuff that is expected to be short. We shouldn't use
* conn->errorMessage either, since this might be only a notice.
*/
initPQExpBuffer(&workBuf);
/*
* Make a PGresult to hold the accumulated fields. We temporarily lie
* about the result status, so that PQmakeEmptyPGresult doesn't uselessly
* copy conn->errorMessage.
*/
res = PQmakeEmptyPGresult(conn, PGRES_EMPTY_QUERY);
if (!res)
goto fail;
res->resultStatus = isError ? PGRES_FATAL_ERROR : PGRES_NONFATAL_ERROR;
/*
* Read the fields and save into res.
*/
for (;;)
{
if (pqGetc(&id, conn))
goto fail;
if (id == '\0')
break; /* terminator found */
if (pqGets(&workBuf, conn))
goto fail;
pqSaveMessageField(res, id, workBuf.data);
}
/*
* Now build the "overall" error message for PQresultErrorMessage.
*/
resetPQExpBuffer(&workBuf);
val = PQresultErrorField(res, PG_DIAG_SEVERITY);
if (val)
appendPQExpBuffer(&workBuf, "%s: ", val);
if (conn->verbosity == PQERRORS_VERBOSE)
{
val = PQresultErrorField(res, PG_DIAG_SQLSTATE);
if (val)
appendPQExpBuffer(&workBuf, "%s: ", val);
}
val = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
if (val)
appendPQExpBufferStr(&workBuf, val);
val = PQresultErrorField(res, PG_DIAG_STATEMENT_POSITION);
if (val)
{
if (conn->verbosity != PQERRORS_TERSE && conn->last_query != NULL)
{
/* emit position as a syntax cursor display */
querytext = conn->last_query;
querypos = atoi(val);
}
else
{
/* emit position as text addition to primary message */
/* translator: %s represents a digit string */
appendPQExpBuffer(&workBuf, libpq_gettext(" at character %s"),
val);
}
}
else
{
val = PQresultErrorField(res, PG_DIAG_INTERNAL_POSITION);
if (val)
{
querytext = PQresultErrorField(res, PG_DIAG_INTERNAL_QUERY);
if (conn->verbosity != PQERRORS_TERSE && querytext != NULL)
{
/* emit position as a syntax cursor display */
querypos = atoi(val);
}
else
{
/* emit position as text addition to primary message */
/* translator: %s represents a digit string */
appendPQExpBuffer(&workBuf, libpq_gettext(" at character %s"),
val);
}
}
}
appendPQExpBufferChar(&workBuf, '\n');
if (conn->verbosity != PQERRORS_TERSE)
{
if (querytext && querypos > 0)
reportErrorPosition(&workBuf, querytext, querypos,
conn->client_encoding);
val = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
if (val)
appendPQExpBuffer(&workBuf, libpq_gettext("DETAIL: %s\n"), val);
val = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
if (val)
appendPQExpBuffer(&workBuf, libpq_gettext("HINT: %s\n"), val);
val = PQresultErrorField(res, PG_DIAG_INTERNAL_QUERY);
if (val)
appendPQExpBuffer(&workBuf, libpq_gettext("QUERY: %s\n"), val);
val = PQresultErrorField(res, PG_DIAG_CONTEXT);
if (val)
appendPQExpBuffer(&workBuf, libpq_gettext("CONTEXT: %s\n"), val);
}
if (conn->verbosity == PQERRORS_VERBOSE)
{
const char *valf;
const char *vall;
valf = PQresultErrorField(res, PG_DIAG_SOURCE_FILE);
vall = PQresultErrorField(res, PG_DIAG_SOURCE_LINE);
val = PQresultErrorField(res, PG_DIAG_SOURCE_FUNCTION);
if (val || valf || vall)
{
appendPQExpBufferStr(&workBuf, libpq_gettext("LOCATION: "));
if (val)
appendPQExpBuffer(&workBuf, libpq_gettext("%s, "), val);
if (valf && vall) /* unlikely we'd have just one */
appendPQExpBuffer(&workBuf, libpq_gettext("%s:%s"),
valf, vall);
appendPQExpBufferChar(&workBuf, '\n');
}
}
/*
* Either save error as current async result, or just emit the notice.
*/
if (isError)
{
res->errMsg = pqResultStrdup(res, workBuf.data);
if (!res->errMsg)
goto fail;
pqClearAsyncResult(conn);
conn->result = res;
resetPQExpBuffer(&conn->errorMessage);
appendPQExpBufferStr(&conn->errorMessage, workBuf.data);
}
else
{
/* We can cheat a little here and not copy the message. */
res->errMsg = workBuf.data;
if (res->noticeHooks.noticeRec != NULL)
(*res->noticeHooks.noticeRec) (res->noticeHooks.noticeRecArg, res);
PQclear(res);
}
termPQExpBuffer(&workBuf);
return 0;
fail:
PQclear(res);
termPQExpBuffer(&workBuf);
return EOF;
}
/*
* parseInput subroutine to read a 'D' (row data) message.
* We add another tuple to the existing PGresult structure.
* Returns: 0 if completed message, EOF if error or not enough data yet.
*
* Note that if we run out of data, we have to suspend and reprocess
* the message after more data is received. We keep a partially constructed
* tuple in conn->curTuple, and avoid reallocating already-allocated storage.
*/
static int
getAnotherTuple(PGconn *conn, int msgLength)
{
PGresult *result = conn->result;
int nfields = result->numAttributes;
PGresAttValue *tup;
int tupnfields; /* # fields from tuple */
int vlen; /* length of the current field value */
int i;
/* Allocate tuple space if first time for this data message */
if (conn->curTuple == NULL)
{
conn->curTuple = (PGresAttValue *)
pqResultAlloc(result, nfields * sizeof(PGresAttValue), TRUE);
if (conn->curTuple == NULL)
goto outOfMemory;
MemSet(conn->curTuple, 0, nfields * sizeof(PGresAttValue));
}
tup = conn->curTuple;
/* Get the field count and make sure it's what we expect */
if (pqGetInt(&tupnfields, 2, conn))
return EOF;
if (tupnfields != nfields)
{
/* Replace partially constructed result with an error result */
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("unexpected field count in \"D\" message\n"));
pqSaveErrorResult(conn);
/* Discard the failed message by pretending we read it */
conn->inCursor = conn->inStart + 5 + msgLength;
return 0;
}
/* Scan the fields */
for (i = 0; i < nfields; i++)
{
/* get the value length */
if (pqGetInt(&vlen, 4, conn))
return EOF;
if (vlen == -1)
{
/* null field */
tup[i].value = result->null_field;
tup[i].len = NULL_LEN;
continue;
}
if (vlen < 0)
vlen = 0;
if (tup[i].value == NULL)
{
bool isbinary = (result->attDescs[i].format != 0);
tup[i].value = (char *) pqResultAlloc(result, vlen + 1, isbinary);
if (tup[i].value == NULL)
goto outOfMemory;
}
tup[i].len = vlen;
/* read in the value */
if (vlen > 0)
if (pqGetnchar((char *) (tup[i].value), vlen, conn))
return EOF;
/* we have to terminate this ourselves */
tup[i].value[vlen] = '\0';
}
/* Success! Store the completed tuple in the result */
if (!pqAddTuple(result, tup))
goto outOfMemory;
/* and reset for a new message */
conn->curTuple = NULL;
return 0;
outOfMemory:
/*
* Replace partially constructed result with an error result. First
* discard the old result to try to win back some memory.
*/
pqClearAsyncResult(conn);
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory for query result\n"));
pqSaveErrorResult(conn);
/* Discard the failed message by pretending we read it */
conn->inCursor = conn->inStart + 5 + msgLength;
return 0;
}
/*
* parseInput subroutine to read a 'B' or 'D' (row data) message.
* We add another tuple to the existing PGresult structure.
* Returns: 0 if completed message, EOF if error or not enough data yet.
*
* Note that if we run out of data, we have to suspend and reprocess
* the message after more data is received. We keep a partially constructed
* tuple in conn->curTuple, and avoid reallocating already-allocated storage.
*/
static int
getAnotherTuple(PGconn *conn, bool binary)
{
PGresult *result = conn->result;
int nfields = result->numAttributes;
PGresAttValue *tup;
/* the backend sends us a bitmap of which attributes are null */
char std_bitmap[64]; /* used unless it doesn't fit */
char *bitmap = std_bitmap;
int i;
size_t nbytes; /* the number of bytes in bitmap */
char bmap; /* One byte of the bitmap */
int bitmap_index; /* Its index */
int bitcnt; /* number of bits examined in current byte */
int vlen; /* length of the current field value */
result->binary = binary;
/* Allocate tuple space if first time for this data message */
if (conn->curTuple == NULL)
{
conn->curTuple = (PGresAttValue *)
pqResultAlloc(result, nfields * sizeof(PGresAttValue), TRUE);
if (conn->curTuple == NULL)
goto outOfMemory;
MemSet(conn->curTuple, 0, nfields * sizeof(PGresAttValue));
/*
* If it's binary, fix the column format indicators. We assume the
* backend will consistently send either B or D, not a mix.
*/
if (binary)
{
for (i = 0; i < nfields; i++)
result->attDescs[i].format = 1;
}
}
tup = conn->curTuple;
/* Get the null-value bitmap */
nbytes = (nfields + BITS_PER_BYTE - 1) / BITS_PER_BYTE;
/* malloc() only for unusually large field counts... */
if (nbytes > sizeof(std_bitmap))
{
bitmap = (char *) malloc(nbytes);
if (!bitmap)
goto outOfMemory;
}
if (pqGetnchar(bitmap, nbytes, conn))
goto EOFexit;
/* Scan the fields */
bitmap_index = 0;
bmap = bitmap[bitmap_index];
bitcnt = 0;
for (i = 0; i < nfields; i++)
{
if (!(bmap & 0200))
{
/* if the field value is absent, make it a null string */
tup[i].value = result->null_field;
tup[i].len = NULL_LEN;
}
else
{
/* get the value length (the first four bytes are for length) */
if (pqGetInt(&vlen, 4, conn))
goto EOFexit;
if (!binary)
vlen = vlen - 4;
if (vlen < 0)
vlen = 0;
if (tup[i].value == NULL)
{
tup[i].value = (char *) pqResultAlloc(result, vlen + 1, binary);
if (tup[i].value == NULL)
goto outOfMemory;
}
tup[i].len = vlen;
/* read in the value */
if (vlen > 0)
if (pqGetnchar((char *) (tup[i].value), vlen, conn))
goto EOFexit;
/* we have to terminate this ourselves */
tup[i].value[vlen] = '\0';
}
/* advance the bitmap stuff */
bitcnt++;
if (bitcnt == BITS_PER_BYTE)
{
bitmap_index++;
bmap = bitmap[bitmap_index];
bitcnt = 0;
}
else
bmap <<= 1;
}
/* Success! Store the completed tuple in the result */
if (!pqAddTuple(result, tup))
goto outOfMemory;
/* and reset for a new message */
conn->curTuple = NULL;
if (bitmap != std_bitmap)
free(bitmap);
return 0;
outOfMemory:
/* Replace partially constructed result with an error result */
/*
* we do NOT use pqSaveErrorResult() here, because of the likelihood that
* there's not enough memory to concatenate messages...
*/
pqClearAsyncResult(conn);
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory for query result\n"));
/*
* XXX: if PQmakeEmptyPGresult() fails, there's probably not much we can
* do to recover...
*/
conn->result = PQmakeEmptyPGresult(conn, PGRES_FATAL_ERROR);
conn->asyncStatus = PGASYNC_READY;
/* Discard the failed message --- good idea? */
conn->inStart = conn->inEnd;
EOFexit:
if (bitmap != NULL && bitmap != std_bitmap)
free(bitmap);
return EOF;
}
