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/*-------------------------------------------------------------------------
*
* fe-exec.c
* functions related to sending a query down to the backend
*
* Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/interfaces/libpq/fe-exec.c
*
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <ctype.h>
#include <fcntl.h>
#include "libpq-fe.h"
#include "libpq-int.h"
#include "mb/pg_wchar.h"
#ifdef WIN32
#include "win32.h"
#else
#include <unistd.h>
#endif
/* keep this in same order as ExecStatusType in libpq-fe.h */
char *const pgresStatus[] = {
"PGRES_EMPTY_QUERY",
"PGRES_COMMAND_OK",
"PGRES_TUPLES_OK",
"PGRES_COPY_OUT",
"PGRES_COPY_IN",
"PGRES_BAD_RESPONSE",
"PGRES_NONFATAL_ERROR",
"PGRES_FATAL_ERROR",
"PGRES_COPY_BOTH",
"PGRES_SINGLE_TUPLE"
};
/*
* static state needed by PQescapeString and PQescapeBytea; initialize to
* values that result in backward-compatible behavior
*/
static int static_client_encoding = PG_SQL_ASCII;
static bool static_std_strings = false;
static PGEvent *dupEvents(PGEvent *events, int count);
static bool pqAddTuple(PGresult *res, PGresAttValue *tup);
static bool PQsendQueryStart(PGconn *conn);
static int PQsendQueryGuts(PGconn *conn,
const char *command,
const char *stmtName,
int nParams,
const Oid *paramTypes,
const char *const * paramValues,
const int *paramLengths,
const int *paramFormats,
int resultFormat);
static void parseInput(PGconn *conn);
static PGresult *getCopyResult(PGconn *conn, ExecStatusType copytype);
static bool PQexecStart(PGconn *conn);
static PGresult *PQexecFinish(PGconn *conn);
static int PQsendDescribe(PGconn *conn, char desc_type,
const char *desc_target);
static int check_field_number(const PGresult *res, int field_num);
/* ----------------
* Space management for PGresult.
*
* Formerly, libpq did a separate malloc() for each field of each tuple
* returned by a query. This was remarkably expensive --- malloc/free
* consumed a sizable part of the application's runtime. And there is
* no real need to keep track of the fields separately, since they will
* all be freed together when the PGresult is released. So now, we grab
* large blocks of storage from malloc and allocate space for query data
* within these blocks, using a trivially simple allocator. This reduces
* the number of malloc/free calls dramatically, and it also avoids
* fragmentation of the malloc storage arena.
* The PGresult structure itself is still malloc'd separately. We could
* combine it with the first allocation block, but that would waste space
* for the common case that no extra storage is actually needed (that is,
* the SQL command did not return tuples).
*
* We also malloc the top-level array of tuple pointers separately, because
* we need to be able to enlarge it via realloc, and our trivial space
* allocator doesn't handle that effectively. (Too bad the FE/BE protocol
* doesn't tell us up front how many tuples will be returned.)
* All other subsidiary storage for a PGresult is kept in PGresult_data blocks
* of size PGRESULT_DATA_BLOCKSIZE. The overhead at the start of each block
* is just a link to the next one, if any. Free-space management info is
* kept in the owning PGresult.
* A query returning a small amount of data will thus require three malloc
* calls: one for the PGresult, one for the tuples pointer array, and one
* PGresult_data block.
*
* Only the most recently allocated PGresult_data block is a candidate to
* have more stuff added to it --- any extra space left over in older blocks
* is wasted. We could be smarter and search the whole chain, but the point
* here is to be simple and fast. Typical applications do not keep a PGresult
* around very long anyway, so some wasted space within one is not a problem.
*
* Tuning constants for the space allocator are:
* PGRESULT_DATA_BLOCKSIZE: size of a standard allocation block, in bytes
* PGRESULT_ALIGN_BOUNDARY: assumed alignment requirement for binary data
* PGRESULT_SEP_ALLOC_THRESHOLD: objects bigger than this are given separate
* blocks, instead of being crammed into a regular allocation block.
* Requirements for correct function are:
* PGRESULT_ALIGN_BOUNDARY must be a multiple of the alignment requirements
* of all machine data types. (Currently this is set from configure
* tests, so it should be OK automatically.)
* PGRESULT_SEP_ALLOC_THRESHOLD + PGRESULT_BLOCK_OVERHEAD <=
* PGRESULT_DATA_BLOCKSIZE
* pqResultAlloc assumes an object smaller than the threshold will fit
* in a new block.
* The amount of space wasted at the end of a block could be as much as
* PGRESULT_SEP_ALLOC_THRESHOLD, so it doesn't pay to make that too large.
* ----------------
*/
#define PGRESULT_DATA_BLOCKSIZE 2048
#define PGRESULT_ALIGN_BOUNDARY MAXIMUM_ALIGNOF /* from configure */
#define PGRESULT_BLOCK_OVERHEAD Max(sizeof(PGresult_data), PGRESULT_ALIGN_BOUNDARY)
#define PGRESULT_SEP_ALLOC_THRESHOLD (PGRESULT_DATA_BLOCKSIZE / 2)
/*
* PQmakeEmptyPGresult
* returns a newly allocated, initialized PGresult with given status.
* If conn is not NULL and status indicates an error, the conn's
* errorMessage is copied. Also, any PGEvents are copied from the conn.
*/
PGresult *
PQmakeEmptyPGresult(PGconn *conn, ExecStatusType status)
{
PGresult *result;
result = (PGresult *) malloc(sizeof(PGresult));
if (!result)
return NULL;
result->ntups = 0;
result->numAttributes = 0;
result->attDescs = NULL;
result->tuples = NULL;
result->tupArrSize = 0;
result->numParameters = 0;
result->paramDescs = NULL;
result->resultStatus = status;
result->cmdStatus[0] = '\0';
result->binary = 0;
result->events = NULL;
result->nEvents = 0;
result->errMsg = NULL;
result->errFields = NULL;
result->null_field[0] = '\0';
result->curBlock = NULL;
result->curOffset = 0;
result->spaceLeft = 0;
if (conn)
{
/* copy connection data we might need for operations on PGresult */
result->noticeHooks = conn->noticeHooks;
result->client_encoding = conn->client_encoding;
/* consider copying conn's errorMessage */
switch (status)
{
case PGRES_EMPTY_QUERY:
case PGRES_COMMAND_OK:
case PGRES_TUPLES_OK:
case PGRES_COPY_OUT:
case PGRES_COPY_IN:
case PGRES_COPY_BOTH:
case PGRES_SINGLE_TUPLE:
/* non-error cases */
break;
default:
pqSetResultError(result, conn->errorMessage.data);
break;
}
/* copy events last; result must be valid if we need to PQclear */
if (conn->nEvents > 0)
{
result->events = dupEvents(conn->events, conn->nEvents);
if (!result->events)
{
PQclear(result);
return NULL;
}
result->nEvents = conn->nEvents;
}
}
else
{
/* defaults... */
result->noticeHooks.noticeRec = NULL;
result->noticeHooks.noticeRecArg = NULL;
result->noticeHooks.noticeProc = NULL;
result->noticeHooks.noticeProcArg = NULL;
result->client_encoding = PG_SQL_ASCII;
}
return result;
}
/*
* PQsetResultAttrs
*
* Set the attributes for a given result. This function fails if there are
* already attributes contained in the provided result. The call is
* ignored if numAttributes is zero or attDescs is NULL. If the
* function fails, it returns zero. If the function succeeds, it
* returns a non-zero value.
*/
int
PQsetResultAttrs(PGresult *res, int numAttributes, PGresAttDesc *attDescs)
{
int i;
/* If attrs already exist, they cannot be overwritten. */
if (!res || res->numAttributes > 0)
return FALSE;
/* ignore no-op request */
if (numAttributes <= 0 || !attDescs)
return TRUE;
res->attDescs = (PGresAttDesc *)
PQresultAlloc(res, numAttributes * sizeof(PGresAttDesc));
if (!res->attDescs)
return FALSE;
res->numAttributes = numAttributes;
memcpy(res->attDescs, attDescs, numAttributes * sizeof(PGresAttDesc));
/* deep-copy the attribute names, and determine format */
res->binary = 1;
for (i = 0; i < res->numAttributes; i++)
{
if (res->attDescs[i].name)
res->attDescs[i].name = pqResultStrdup(res, res->attDescs[i].name);
else
res->attDescs[i].name = res->null_field;
if (!res->attDescs[i].name)
return FALSE;
if (res->attDescs[i].format == 0)
res->binary = 0;
}
return TRUE;
}
/*
* PQcopyResult
*
* Returns a deep copy of the provided 'src' PGresult, which cannot be NULL.
* The 'flags' argument controls which portions of the result will or will
* NOT be copied. The created result is always put into the
* PGRES_TUPLES_OK status. The source result error message is not copied,
* although cmdStatus is.
*
* To set custom attributes, use PQsetResultAttrs. That function requires
* that there are no attrs contained in the result, so to use that
* function you cannot use the PG_COPYRES_ATTRS or PG_COPYRES_TUPLES
* options with this function.
*
* Options:
* PG_COPYRES_ATTRS - Copy the source result's attributes
*
* PG_COPYRES_TUPLES - Copy the source result's tuples. This implies
* copying the attrs, seeing how the attrs are needed by the tuples.
*
* PG_COPYRES_EVENTS - Copy the source result's events.
*
* PG_COPYRES_NOTICEHOOKS - Copy the source result's notice hooks.
*/
PGresult *
PQcopyResult(const PGresult *src, int flags)
{
PGresult *dest;
int i;
if (!src)
return NULL;
dest = PQmakeEmptyPGresult(NULL, PGRES_TUPLES_OK);
if (!dest)
return NULL;
/* Always copy these over. Is cmdStatus really useful here? */
dest->client_encoding = src->client_encoding;
strcpy(dest->cmdStatus, src->cmdStatus);
/* Wants attrs? */
if (flags & (PG_COPYRES_ATTRS | PG_COPYRES_TUPLES))
{
if (!PQsetResultAttrs(dest, src->numAttributes, src->attDescs))
{
PQclear(dest);
return NULL;
}
}
/* Wants to copy tuples? */
if (flags & PG_COPYRES_TUPLES)
{
int tup,
field;
for (tup = 0; tup < src->ntups; tup++)
{
for (field = 0; field < src->numAttributes; field++)
{
if (!PQsetvalue(dest, tup, field,
src->tuples[tup][field].value,
src->tuples[tup][field].len))
{
PQclear(dest);
return NULL;
}
}
}
}
/* Wants to copy notice hooks? */
if (flags & PG_COPYRES_NOTICEHOOKS)
dest->noticeHooks = src->noticeHooks;
/* Wants to copy PGEvents? */
if ((flags & PG_COPYRES_EVENTS) && src->nEvents > 0)
{
dest->events = dupEvents(src->events, src->nEvents);
if (!dest->events)
{
PQclear(dest);
return NULL;
}
dest->nEvents = src->nEvents;
}
/* Okay, trigger PGEVT_RESULTCOPY event */
for (i = 0; i < dest->nEvents; i++)
{
if (src->events[i].resultInitialized)
{
PGEventResultCopy evt;
evt.src = src;
evt.dest = dest;
if (!dest->events[i].proc(PGEVT_RESULTCOPY, &evt,
dest->events[i].passThrough))
{
PQclear(dest);
return NULL;
}
dest->events[i].resultInitialized = TRUE;
}
}
return dest;
}
/*
* Copy an array of PGEvents (with no extra space for more).
* Does not duplicate the event instance data, sets this to NULL.
* Also, the resultInitialized flags are all cleared.
*/
static PGEvent *
dupEvents(PGEvent *events, int count)
{
PGEvent *newEvents;
int i;
if (!events || count <= 0)
return NULL;
newEvents = (PGEvent *) malloc(count * sizeof(PGEvent));
if (!newEvents)
return NULL;
for (i = 0; i < count; i++)
{
newEvents[i].proc = events[i].proc;
newEvents[i].passThrough = events[i].passThrough;
newEvents[i].data = NULL;
newEvents[i].resultInitialized = FALSE;
newEvents[i].name = strdup(events[i].name);
if (!newEvents[i].name)
{
while (--i >= 0)
free(newEvents[i].name);
free(newEvents);
return NULL;
}
}
return newEvents;
}
/*
* Sets the value for a tuple field. The tup_num must be less than or
* equal to PQntuples(res). If it is equal, a new tuple is created and
* added to the result.
* Returns a non-zero value for success and zero for failure.
*/
int
PQsetvalue(PGresult *res, int tup_num, int field_num, char *value, int len)
{
PGresAttValue *attval;
if (!check_field_number(res, field_num))
return FALSE;
/* Invalid tup_num, must be <= ntups */
if (tup_num < 0 || tup_num > res->ntups)
return FALSE;
/* need to allocate a new tuple? */
if (tup_num == res->ntups)
{
PGresAttValue *tup;
int i;
tup = (PGresAttValue *)
pqResultAlloc(res, res->numAttributes * sizeof(PGresAttValue),
TRUE);
if (!tup)
return FALSE;
/* initialize each column to NULL */
for (i = 0; i < res->numAttributes; i++)
{
tup[i].len = NULL_LEN;
tup[i].value = res->null_field;
}
/* add it to the array */
if (!pqAddTuple(res, tup))
return FALSE;
}
attval = &res->tuples[tup_num][field_num];
/* treat either NULL_LEN or NULL value pointer as a NULL field */
if (len == NULL_LEN || value == NULL)
{
attval->len = NULL_LEN;
attval->value = res->null_field;
}
else if (len <= 0)
{
attval->len = 0;
attval->value = res->null_field;
}
else
{
attval->value = (char *) pqResultAlloc(res, len + 1, TRUE);
if (!attval->value)
return FALSE;
attval->len = len;
memcpy(attval->value, value, len);
attval->value[len] = '\0';
}
return TRUE;
}
/*
* pqResultAlloc - exported routine to allocate local storage in a PGresult.
*
* We force all such allocations to be maxaligned, since we don't know
* whether the value might be binary.
*/
void *
PQresultAlloc(PGresult *res, size_t nBytes)
{
return pqResultAlloc(res, nBytes, TRUE);
}
/*
* pqResultAlloc -
* Allocate subsidiary storage for a PGresult.
*
* nBytes is the amount of space needed for the object.
* If isBinary is true, we assume that we need to align the object on
* a machine allocation boundary.
* If isBinary is false, we assume the object is a char string and can
* be allocated on any byte boundary.
*/
void *
pqResultAlloc(PGresult *res, size_t nBytes, bool isBinary)
{
char *space;
PGresult_data *block;
if (!res)
return NULL;
if (nBytes <= 0)
return res->null_field;
/*
* If alignment is needed, round up the current position to an alignment
* boundary.
*/
if (isBinary)
{
int offset = res->curOffset % PGRESULT_ALIGN_BOUNDARY;
if (offset)
{
res->curOffset += PGRESULT_ALIGN_BOUNDARY - offset;
res->spaceLeft -= PGRESULT_ALIGN_BOUNDARY - offset;
}
}
/* If there's enough space in the current block, no problem. */
if (nBytes <= (size_t) res->spaceLeft)
{
space = res->curBlock->space + res->curOffset;
res->curOffset += nBytes;
res->spaceLeft -= nBytes;
return space;
}
/*
* If the requested object is very large, give it its own block; this
* avoids wasting what might be most of the current block to start a new
* block. (We'd have to special-case requests bigger than the block size
* anyway.) The object is always given binary alignment in this case.
*/
if (nBytes >= PGRESULT_SEP_ALLOC_THRESHOLD)
{
block = (PGresult_data *) malloc(nBytes + PGRESULT_BLOCK_OVERHEAD);
if (!block)
return NULL;
space = block->space + PGRESULT_BLOCK_OVERHEAD;
if (res->curBlock)
{
/*
* Tuck special block below the active block, so that we don't
* have to waste the free space in the active block.
*/
block->next = res->curBlock->next;
res->curBlock->next = block;
}
else
{
/* Must set up the new block as the first active block. */
block->next = NULL;
res->curBlock = block;
res->spaceLeft = 0; /* be sure it's marked full */
}
return space;
}
/* Otherwise, start a new block. */
block = (PGresult_data *) malloc(PGRESULT_DATA_BLOCKSIZE);
if (!block)
return NULL;
block->next = res->curBlock;
res->curBlock = block;
if (isBinary)
{
/* object needs full alignment */
res->curOffset = PGRESULT_BLOCK_OVERHEAD;
res->spaceLeft = PGRESULT_DATA_BLOCKSIZE - PGRESULT_BLOCK_OVERHEAD;
}
else
{
/* we can cram it right after the overhead pointer */
res->curOffset = sizeof(PGresult_data);
res->spaceLeft = PGRESULT_DATA_BLOCKSIZE - sizeof(PGresult_data);
}
space = block->space + res->curOffset;
res->curOffset += nBytes;
res->spaceLeft -= nBytes;
return space;
}
/*
* pqResultStrdup -
* Like strdup, but the space is subsidiary PGresult space.
*/
char *
pqResultStrdup(PGresult *res, const char *str)
{
char *space = (char *) pqResultAlloc(res, strlen(str) + 1, FALSE);
if (space)
strcpy(space, str);
return space;
}
/*
* pqSetResultError -
* assign a new error message to a PGresult
*/
void
pqSetResultError(PGresult *res, const char *msg)
{
if (!res)
return;
if (msg && *msg)
res->errMsg = pqResultStrdup(res, msg);
else
res->errMsg = NULL;
}
/*
* pqCatenateResultError -
* concatenate a new error message to the one already in a PGresult
*/
void
pqCatenateResultError(PGresult *res, const char *msg)
{
PQExpBufferData errorBuf;
if (!res || !msg)
return;
initPQExpBuffer(&errorBuf);
if (res->errMsg)
appendPQExpBufferStr(&errorBuf, res->errMsg);
appendPQExpBufferStr(&errorBuf, msg);
pqSetResultError(res, errorBuf.data);
termPQExpBuffer(&errorBuf);
}
/*
* PQclear -
* free's the memory associated with a PGresult
*/
void
PQclear(PGresult *res)
{
PGresult_data *block;
int i;
if (!res)
return;
for (i = 0; i < res->nEvents; i++)
{
/* only send DESTROY to successfully-initialized event procs */
if (res->events[i].resultInitialized)
{
PGEventResultDestroy evt;
evt.result = res;
(void) res->events[i].proc(PGEVT_RESULTDESTROY, &evt,
res->events[i].passThrough);
}
free(res->events[i].name);
}
if (res->events)
free(res->events);
/* Free all the subsidiary blocks */
while ((block = res->curBlock) != NULL)
{
res->curBlock = block->next;
free(block);
}
/* Free the top-level tuple pointer array */
if (res->tuples)
free(res->tuples);
/* zero out the pointer fields to catch programming errors */
res->attDescs = NULL;
res->tuples = NULL;
res->paramDescs = NULL;
res->errFields = NULL;
res->events = NULL;
res->nEvents = 0;
/* res->curBlock was zeroed out earlier */
/* Free the PGresult structure itself */
free(res);
}
/*
* Handy subroutine to deallocate any partially constructed async result.
*
* Any "next" result gets cleared too.
*/
void
pqClearAsyncResult(PGconn *conn)
{
if (conn->result)
PQclear(conn->result);
conn->result = NULL;
if (conn->next_result)
PQclear(conn->next_result);
conn->next_result = NULL;
}
/*
* This subroutine deletes any existing async result, sets conn->result
* to a PGresult with status PGRES_FATAL_ERROR, and stores the current
* contents of conn->errorMessage into that result. It differs from a
* plain call on PQmakeEmptyPGresult() in that if there is already an
* async result with status PGRES_FATAL_ERROR, the current error message
* is APPENDED to the old error message instead of replacing it. This
* behavior lets us report multiple error conditions properly, if necessary.
* (An example where this is needed is when the backend sends an 'E' message
* and immediately closes the connection --- we want to report both the
* backend error and the connection closure error.)
*/
void
pqSaveErrorResult(PGconn *conn)
{
/*
* If no old async result, just let PQmakeEmptyPGresult make one. Likewise
* if old result is not an error message.
*/
if (conn->result == NULL ||
conn->result->resultStatus != PGRES_FATAL_ERROR ||
conn->result->errMsg == NULL)
{
pqClearAsyncResult(conn);
conn->result = PQmakeEmptyPGresult(conn, PGRES_FATAL_ERROR);
}
else
{
/* Else, concatenate error message to existing async result. */
pqCatenateResultError(conn->result, conn->errorMessage.data);
}
}
/*
* This subroutine prepares an async result object for return to the caller.
* If there is not already an async result object, build an error object
* using whatever is in conn->errorMessage. In any case, clear the async
* result storage and make sure PQerrorMessage will agree with the result's
* error string.
*/
PGresult *
pqPrepareAsyncResult(PGconn *conn)
{
PGresult *res;
/*
* conn->result is the PGresult to return. If it is NULL (which probably
* shouldn't happen) we assume there is an appropriate error message in
* conn->errorMessage.
*/
res = conn->result;
if (!res)
res = PQmakeEmptyPGresult(conn, PGRES_FATAL_ERROR);
else
{
/*
* Make sure PQerrorMessage agrees with result; it could be different
* if we have concatenated messages.
*/
resetPQExpBuffer(&conn->errorMessage);
appendPQExpBufferStr(&conn->errorMessage,
PQresultErrorMessage(res));
}
/*
* Replace conn->result with next_result, if any. In the normal case
* there isn't a next result and we're just dropping ownership of the
* current result. In single-row mode this restores the situation to what
* it was before we created the current single-row result.
*/
conn->result = conn->next_result;
conn->next_result = NULL;
return res;
}
/*
* pqInternalNotice - produce an internally-generated notice message
*
* A format string and optional arguments can be passed. Note that we do
* libpq_gettext() here, so callers need not.
*
* The supplied text is taken as primary message (ie., it should not include
* a trailing newline, and should not be more than one line).
*/
void
pqInternalNotice(const PGNoticeHooks *hooks, const char *fmt,...)
{
char msgBuf[1024];
va_list args;
PGresult *res;
if (hooks->noticeRec == NULL)
return; /* nobody home to receive notice? */
/* Format the message */
va_start(args, fmt);
vsnprintf(msgBuf, sizeof(msgBuf), libpq_gettext(fmt), args);
va_end(args);
msgBuf[sizeof(msgBuf) - 1] = '\0'; /* make real sure it's terminated */
/* Make a PGresult to pass to the notice receiver */
res = PQmakeEmptyPGresult(NULL, PGRES_NONFATAL_ERROR);
if (!res)
return;
res->noticeHooks = *hooks;
/*
* Set up fields of notice.
*/
pqSaveMessageField(res, PG_DIAG_MESSAGE_PRIMARY, msgBuf);
pqSaveMessageField(res, PG_DIAG_SEVERITY, libpq_gettext("NOTICE"));
/* XXX should provide a SQLSTATE too? */
/*
* Result text is always just the primary message + newline. If we can't
* allocate it, don't bother invoking the receiver.
*/
res->errMsg = (char *) pqResultAlloc(res, strlen(msgBuf) + 2, FALSE);
if (res->errMsg)
{
sprintf(res->errMsg, "%s\n", msgBuf);
/*
* Pass to receiver, then free it.
*/
(*res->noticeHooks.noticeRec) (res->noticeHooks.noticeRecArg, res);
}
PQclear(res);
}
/*
* pqAddTuple
* add a row pointer to the PGresult structure, growing it if necessary
* Returns TRUE if OK, FALSE if not enough memory to add the row
*/
static bool
pqAddTuple(PGresult *res, PGresAttValue *tup)
{
if (res->ntups >= res->tupArrSize)
{
/*
* Try to grow the array.
*
* We can use realloc because shallow copying of the structure is
* okay. Note that the first time through, res->tuples is NULL. While
* ANSI says that realloc() should act like malloc() in that case,
* some old C libraries (like SunOS 4.1.x) coredump instead. On
* failure realloc is supposed to return NULL without damaging the
* existing allocation. Note that the positions beyond res->ntups are
* garbage, not necessarily NULL.
*/
int newSize = (res->tupArrSize > 0) ? res->tupArrSize * 2 : 128;
PGresAttValue **newTuples;
if (res->tuples == NULL)
newTuples = (PGresAttValue **)
malloc(newSize * sizeof(PGresAttValue *));
else
newTuples = (PGresAttValue **)
realloc(res->tuples, newSize * sizeof(PGresAttValue *));
if (!newTuples)
return FALSE; /* malloc or realloc failed */
res->tupArrSize = newSize;
res->tuples = newTuples;
}
res->tuples[res->ntups] = tup;
res->ntups++;
return TRUE;
}
/*
* pqSaveMessageField - save one field of an error or notice message
*/
void
pqSaveMessageField(PGresult *res, char code, const char *value)
{
PGMessageField *pfield;
pfield = (PGMessageField *)
pqResultAlloc(res,
sizeof(PGMessageField) + strlen(value),
TRUE);
if (!pfield)
return; /* out of memory? */
pfield->code = code;
strcpy(pfield->contents, value);
pfield->next = res->errFields;
res->errFields = pfield;
}
/*
* pqSaveParameterStatus - remember parameter status sent by backend
*/
void
pqSaveParameterStatus(PGconn *conn, const char *name, const char *value)
{
pgParameterStatus *pstatus;
pgParameterStatus *prev;
if (conn->Pfdebug)
fprintf(conn->Pfdebug, "pqSaveParameterStatus: '%s' = '%s'\n",
name, value);
/*
* Forget any old information about the parameter
*/
for (pstatus = conn->pstatus, prev = NULL;
pstatus != NULL;
prev = pstatus, pstatus = pstatus->next)
{
if (strcmp(pstatus->name, name) == 0)
{
if (prev)
prev->next = pstatus->next;
else
conn->pstatus = pstatus->next;
free(pstatus); /* frees name and value strings too */
break;
}
}
/*
* Store new info as a single malloc block
*/
pstatus = (pgParameterStatus *) malloc(sizeof(pgParameterStatus) +
strlen(name) +strlen(value) + 2);
if (pstatus)
{
char *ptr;
ptr = ((char *) pstatus) + sizeof(pgParameterStatus);
pstatus->name = ptr;
strcpy(ptr, name);
ptr += strlen(name) + 1;
pstatus->value = ptr;
strcpy(ptr, value);
pstatus->next = conn->pstatus;
conn->pstatus = pstatus;
}
/*
* Special hacks: remember client_encoding and
* standard_conforming_strings, and convert server version to a numeric
* form. We keep the first two of these in static variables as well, so
* that PQescapeString and PQescapeBytea can behave somewhat sanely (at
* least in single-connection-using programs).
*/
if (strcmp(name, "client_encoding") == 0)
{
conn->client_encoding = pg_char_to_encoding(value);
/* if we don't recognize the encoding name, fall back to SQL_ASCII */
if (conn->client_encoding < 0)
conn->client_encoding = PG_SQL_ASCII;
static_client_encoding = conn->client_encoding;
}
else if (strcmp(name, "standard_conforming_strings") == 0)
{
conn->std_strings = (strcmp(value, "on") == 0);
static_std_strings = conn->std_strings;
}
else if (strcmp(name, "server_version") == 0)
{
int cnt;
int vmaj,
vmin,
vrev;
cnt = sscanf(value, "%d.%d.%d", &vmaj, &vmin, &vrev);
if (cnt < 2)
conn->sversion = 0; /* unknown */
else
{
if (cnt == 2)
vrev = 0;
conn->sversion = (100 * vmaj + vmin) * 100 + vrev;
}
}
}
/*
* pqRowProcessor
* Add the received row to the current async result (conn->result).
* Returns 1 if OK, 0 if error occurred.
*