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fe-exec.c 42.66 KiB
/*-------------------------------------------------------------------------
*
* fe-exec.c--
* functions related to sending a query down to the backend
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-exec.c,v 1.49 1998/04/29 02:04:01 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include "postgres.h"
#include "libpq/pqcomm.h"
#include "libpq/pqsignal.h"
#include "libpq-fe.h"
#include <sys/ioctl.h>
#ifndef HAVE_TERMIOS_H
#include <sys/termios.h>
#else
#include <termios.h>
#endif
#ifdef TIOCGWINSZ
struct winsize screen_size;
#else
struct winsize
{
int ws_row;
int ws_col;
} screen_size;
#endif
/* the rows array in a PGresGroup has to grow to accommodate the rows */
/* returned. Each time, we grow by this much: */
#define TUPARR_GROW_BY 100
/* keep this in same order as ExecStatusType in pgtclCmds.h */
const char *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"
};
static PGresult *makePGresult(PGconn *conn, char *pname);
static void addTuple(PGresult *res, PGresAttValue *tup);
static PGresAttValue *getTuple(PGconn *conn, PGresult *res, int binary);
static PGresult *makeEmptyPGresult(PGconn *conn, ExecStatusType status);
static void fill(int length, int max, char filler, FILE *fp);
static char *
do_header(FILE *fout, PQprintOpt *po, const int nFields,
int fieldMax[], char *fieldNames[], unsigned char fieldNotNum[],
const int fs_len, PGresult *res);
/*
* PQclear -
* free's the memory associated with a PGresult
*
*/
void
PQclear(PGresult *res)
{
int i,
j;
if (!res)
return;
/* free all the rows */
for (i = 0; i < res->ntups; i++)
{
for (j = 0; j < res->numAttributes; j++)
{
if (res->tuples[i][j].value)
free(res->tuples[i][j].value);
}
if (res->tuples[i])
free(res->tuples[i]);
}
if (res->tuples)
free(res->tuples);
/* free all the attributes */
for (i = 0; i < res->numAttributes; i++)
{
if (res->attDescs[i].name)
free(res->attDescs[i].name);
}
if (res->attDescs)
free(res->attDescs);
/* free the structure itself */
free(res);
}
/*
* PGresult -
* returns a newly allocated, initialized PGresult
*
*/
static PGresult *
makeEmptyPGresult(PGconn *conn, ExecStatusType status)
{
PGresult *result;
result = (PGresult *) malloc(sizeof(PGresult));
result->conn = conn;
result->ntups = 0;
result->numAttributes = 0;
result->attDescs = NULL;
result->tuples = NULL;
result->tupArrSize = 0;
result->resultStatus = status;
result->cmdStatus[0] = '\0';
result->binary = 0;
return result;
}
/*
* getTuple -
* get the next row from the stream *
* the CALLER is responsible from freeing the PGresAttValue returned
*/
static PGresAttValue *
getTuple(PGconn *conn, PGresult *result, int binary)
{
char bitmap[MAX_FIELDS]; /* the backend sends us a bitmap
* of */
/* which attributes are null */
int bitmap_index = 0;
int i;
int nbytes; /* the number of bytes in bitmap */
char bmap; /* One byte of the bitmap */
int bitcnt = 0; /* number of bits examined in current byte */
int vlen; /* length of the current field value */
FILE *pfin = conn->Pfin;
FILE *pfdebug = conn->Pfdebug;
PGresAttValue *tup;
int nfields = result->numAttributes;
result->binary = binary;
tup = (PGresAttValue *) malloc(nfields * sizeof(PGresAttValue));
nbytes = nfields / BYTELEN;
if ((nfields % BYTELEN) > 0)
nbytes++;
if (nbytes >= MAX_FIELDS || pqGetnchar(bitmap, nbytes, pfin, pfdebug) == 1)
{
sprintf(conn->errorMessage,
"Error reading null-values bitmap from row data stream\n");
return NULL;
}
bmap = bitmap[bitmap_index];
for (i = 0; i < nfields; i++)
{
if (!(bmap & 0200))
{
/* if the field value is absent, make it '\0' */
tup[i].value = (char *) malloc(1);
tup[i].value[0] = '\0';
tup[i].len = NULL_LEN;
}
else
{
/* get the value length (the first four bytes are for length) */
pqGetInt(&vlen, 4, pfin, pfdebug);
if (binary == 0)
{
vlen = vlen - 4;
}
if (vlen < 0)
vlen = 0;
tup[i].len = vlen;
tup[i].value = (char *) malloc(vlen + 1);
/* read in the value; */
if (vlen > 0)
pqGetnchar((char *) (tup[i].value), vlen, pfin, pfdebug);
tup[i].value[vlen] = '\0';
}
/* get the appropriate bitmap */
bitcnt++;
if (bitcnt == BYTELEN) {
bitmap_index++;
bmap = bitmap[bitmap_index];
bitcnt = 0;
}
else
bmap <<= 1;
}
return tup;
}
/*
* addTuple
* add a row to the PGresult structure, growing it if necessary
* to accommodate
*
*/
static void
addTuple(PGresult *res, PGresAttValue *tup)
{
if (res->ntups == res->tupArrSize)
{
/* grow the array */
res->tupArrSize += TUPARR_GROW_BY;
if (res->ntups == 0)
res->tuples = (PGresAttValue **)
malloc(res->tupArrSize * sizeof(PGresAttValue *));
else
/*
* we can use realloc because shallow copying of the structure
* is okay
*/
res->tuples = (PGresAttValue **)
realloc(res->tuples, res->tupArrSize * sizeof(PGresAttValue *));
}
res->tuples[res->ntups] = tup;
res->ntups++;
}
/*
* PGresult
* fill out the PGresult structure with result rows from the backend
* this is called after query has been successfully run and we have
* a portal name
*
* ASSUMPTION: we assume only *1* row group is returned from the backend
*
* the CALLER is reponsible for free'ing the new PGresult allocated here
*
*/
static PGresult *
makePGresult(PGconn *conn, char *pname)
{
PGresult *result;
int id;
int nfields;
int i;
int done = 0;
PGresAttValue *newTup;
FILE *pfin = conn->Pfin;
FILE *pfdebug = conn->Pfdebug;
result = makeEmptyPGresult(conn, PGRES_TUPLES_OK);
/* makePGresult() should only be called when the */
/* id of the stream is 'T' to start with */
/* the next two bytes are the number of fields */
if (pqGetInt(&nfields, 2, pfin, pfdebug) == 1)
{
sprintf(conn->errorMessage,
"could not get the number of fields from the 'T' message\n");
goto makePGresult_badResponse_return;
}
else
result->numAttributes = nfields;
/* allocate space for the attribute descriptors */
if (nfields > 0)
{
result->attDescs = (PGresAttDesc *) malloc(nfields * sizeof(PGresAttDesc));
}
/* get type info */
for (i = 0; i < nfields; i++)
{
char typName[MAX_MESSAGE_LEN];
int adtid;
int adtsize;
if (pqGets(typName, MAX_MESSAGE_LEN, pfin, pfdebug) ||
pqGetInt(&adtid, 4, pfin, pfdebug) ||
pqGetInt(&adtsize, 2, pfin, pfdebug))
{
sprintf(conn->errorMessage,
"error reading type information from the 'T' message\n");
goto makePGresult_badResponse_return;
}
result->attDescs[i].name = malloc(strlen(typName) + 1);
strcpy(result->attDescs[i].name, typName);
result->attDescs[i].adtid = adtid;
result->attDescs[i].adtsize = adtsize; /* casting from int to
* int2 here */
}
id = pqGetc(pfin, pfdebug);
/* process the data stream until we're finished */
while (!done)
{
switch (id)
{
case 'T': /* a new row group */
sprintf(conn->errorMessage,
"makePGresult() -- "
"is not equipped to handle multiple row groups.\n");
goto makePGresult_badResponse_return;
case 'B': /* a row in binary format */
case 'D': /* a row in ASCII format */
newTup = getTuple(conn, result, (id == 'B'));
if (newTup == NULL)
goto makePGresult_badResponse_return;
addTuple(result, newTup);
break;
case 'C': /* end of portal row stream */
{
char command[MAX_MESSAGE_LEN];
pqGets(command, MAX_MESSAGE_LEN, pfin, pfdebug); /* read command tag */
done = 1;
}
break; case 'E': /* errors */
if (pqGets(conn->errorMessage, ERROR_MSG_LENGTH, pfin, pfdebug) == 1)
{
sprintf(conn->errorMessage,
"Error return detected from backend, "
"but error message cannot be read");
}
result->resultStatus = PGRES_FATAL_ERROR;
return result;
break;
case 'N': /* notices from the backend */
if (pqGets(conn->errorMessage, ERROR_MSG_LENGTH, pfin, pfdebug) == 1)
{
sprintf(conn->errorMessage,
"Notice return detected from backend, "
"but error message cannot be read");
}
else
/* XXXX send Notices to stderr for now */
fprintf(stderr, "%s\n", conn->errorMessage);
break;
default: /* uh-oh this should never happen but
* frequently does when the backend dumps
* core */
sprintf(conn->errorMessage,
"FATAL: unrecognized data from the backend. "
"It probably dumped core.\n");
fprintf(stderr, conn->errorMessage);
result->resultStatus = PGRES_FATAL_ERROR;
return result;
break;
}
if (!done)
id = getc(pfin);
} /* while (1) */
result->resultStatus = PGRES_TUPLES_OK;
return result;
makePGresult_badResponse_return:
result->resultStatus = PGRES_BAD_RESPONSE;
return result;
}
/*
* Assuming that we just sent a query to the backend, read the backend's
* response from stream <pfin> and respond accordingly.
*
* If <pfdebug> is non-null, write to that stream whatever we receive
* (it's a debugging trace).
*
* Return as <result> a pointer to a proper final PGresult structure,
* newly allocated, for the query based on the response we get. If the
* response we get indicates that the query didn't execute, return a
* null pointer and don't allocate any space, but also place a text
* string explaining the problem at <*reason>.
*/
static void
process_response_from_backend(FILE *pfin, FILE *pfout, FILE *pfdebug,
PGconn *conn,
PGresult **result_p, char *const reason)
{
int id;
/*
* The protocol character received from the backend. The protocol * character is the first character in the backend's response to our
* query. It defines the nature of the response.
*/
PGnotify *newNotify;
bool done;
/* We're all done with the query and ready to return the result. */
int emptiesSent;
/*
* Number of empty queries we have sent in order to flush out multiple
* responses, less the number of corresponding responses we have
* received.
*/
int errors;
/*
* If an error is received, we must still drain out the empty queries
* sent. So we need another flag.
*/
char cmdStatus[MAX_MESSAGE_LEN];
char pname[MAX_MESSAGE_LEN]; /* portal name */
/*
* loop because multiple messages, especially NOTICES, can come back
* from the backend. NOTICES are output directly to stderr
*/
emptiesSent = 0; /* No empty queries sent yet */
errors = 0; /* No errors received yet */
pname[0] = '\0';
done = false; /* initial value */
while (!done)
{
/* read the result id */
id = pqGetc(pfin, pfdebug);
if (id == EOF)
{
/* hmm, no response from the backend-end, that's bad */
(void) sprintf(reason, "PQexec() -- Request was sent to backend"
", but backend closed the channel before responding."
"\n\tThis probably means the backend terminated abnormally"
" before or while processing the request.\n");
conn->status = CONNECTION_BAD; /* No more connection to
* backend */
*result_p = (PGresult *) NULL;
done = true;
}
else
{
switch (id)
{
case 'A':
newNotify = (PGnotify *) malloc(sizeof(PGnotify));
pqGetInt(&(newNotify->be_pid), 4, pfin, pfdebug);
pqGets(newNotify->relname, NAMEDATALEN, pfin, pfdebug);
DLAddTail(conn->notifyList, DLNewElem(newNotify));
/*
* async messages are piggy'ed back on other messages,
* so we stay in the while loop for other messages
*/
break;
case 'C': /* portal query command, no rows returned */
if (pqGets(cmdStatus, MAX_MESSAGE_LEN, pfin, pfdebug) == 1)
{
sprintf(reason,
"PQexec() -- query command completed, "
"but return message from backend cannot be read."); *result_p = (PGresult *) NULL;
done = true;
}
else
{
/*
* since backend may produce more than one result
* for some commands need to poll until clear send
* an empty query down, and keep reading out of
* the pipe until an 'I' is received.
*/
pqPuts("Q ", pfout, pfdebug); /* send an empty query */
/*
* Increment a flag and process messages in the
* usual way because there may be async
* notifications pending. DZ - 31-8-1996
*/
emptiesSent++;
}
break;
case 'E': /* error return */
if (pqGets(conn->errorMessage, ERROR_MSG_LENGTH, pfin, pfdebug) == 1)
{
(void) sprintf(reason,
"PQexec() -- error return detected from backend, "
"but attempt to read the error message failed.");
}
*result_p = (PGresult *) NULL;
errors++;
if (emptiesSent == 0)
{
done = true;
}
break;
case 'I':
{ /* empty query */
/* read and throw away the closing '\0' */
int c;
if ((c = pqGetc(pfin, pfdebug)) != '\0')
{
fprintf(stderr, "error!, unexpected character %c following 'I'\n", c);
}
if (emptiesSent)
{
if (--emptiesSent == 0)
{ /* is this the last one? */
/*
* If this is the result of a portal query
* command set the command status and
* message accordingly. DZ - 31-8-1996
*/
if (!errors)
{
*result_p = makeEmptyPGresult(conn, PGRES_COMMAND_OK);
strncpy((*result_p)->cmdStatus, cmdStatus, CMDSTATUS_LEN - 1);
}
else
{
*result_p = (PGresult *) NULL;
}
done = true;
}
}
else
{
if (!errors) {
*result_p = makeEmptyPGresult(conn, PGRES_EMPTY_QUERY);
}
else
{
*result_p = (PGresult *) NULL;
}
done = true;
}
}
break;
case 'N': /* notices from the backend */
if (pqGets(reason, ERROR_MSG_LENGTH, pfin, pfdebug) == 1)
{
sprintf(reason,
"PQexec() -- Notice detected from backend, "
"but attempt to read the notice failed.");
*result_p = (PGresult *) NULL;
done = true;
}
else
/*
* Should we really be doing this? These notices
* are not important enough for us to presume to
* put them on stderr. Maybe the caller should
* decide whether to put them on stderr or not.
* BJH 96.12.27
*/
fprintf(stderr, "%s", reason);
break;
case 'P': /* synchronous (normal) portal */
pqGets(pname, MAX_MESSAGE_LEN, pfin, pfdebug); /* read in portal name */
break;
case 'T': /* actual row results: */
*result_p = makePGresult(conn, pname);
done = true;
break;
case 'D': /* copy command began successfully */
*result_p = makeEmptyPGresult(conn, PGRES_COPY_IN);
done = true;
break;
case 'B': /* copy command began successfully */
*result_p = makeEmptyPGresult(conn, PGRES_COPY_OUT);
done = true;
break;
default:
sprintf(reason,
"unknown protocol character '%c' read from backend. "
"(The protocol character is the first character the "
"backend sends in response to a query it receives).\n",
id);
*result_p = (PGresult *) NULL;
done = true;
} /* switch on protocol character */
} /* if character was received */
} /* while not done */
}
/*
* PQexec
* send a query to the backend and package up the result in a Pgresult
*
* if the query failed, return NULL, conn->errorMessage is set to
* a relevant message
* if query is successful, a new PGresult is returned
* the use is responsible for freeing that structure when done with it
* */
PGresult *
PQexec(PGconn *conn, const char *query)
{
PGresult *result;
char buffer[MAX_MESSAGE_LEN];
if (!conn)
return NULL;
if (!query)
{
sprintf(conn->errorMessage, "PQexec() -- query pointer is null.");
return NULL;
}
/* clear the error string */
conn->errorMessage[0] = '\0';
/* check to see if the query string is too long */
if (strlen(query) > MAX_MESSAGE_LEN)
{
sprintf(conn->errorMessage, "PQexec() -- query is too long. "
"Maximum length is %d\n", MAX_MESSAGE_LEN - 2);
return NULL;
}
/* Don't try to send if we know there's no live connection. */
if (conn->status != CONNECTION_OK)
{
sprintf(conn->errorMessage, "PQexec() -- There is no connection "
"to the backend.\n");
return NULL;
}
/* the frontend-backend protocol uses 'Q' to designate queries */
sprintf(buffer, "Q%s", query);
/* send the query to the backend; */
if (pqPuts(buffer, conn->Pfout, conn->Pfdebug) == 1)
{
(void) sprintf(conn->errorMessage,
"PQexec() -- while sending query: %s\n"
"-- fprintf to Pfout failed: errno=%d\n%s\n",
query, errno, strerror(errno));
return NULL;
}
process_response_from_backend(conn->Pfin, conn->Pfout, conn->Pfdebug, conn,
&result, conn->errorMessage);
return (result);
}
/*
* PQnotifies
* returns a PGnotify* structure of the latest async notification
* that has not yet been handled
*
* returns NULL, if there is currently
* no unhandled async notification from the backend
*
* the CALLER is responsible for FREE'ing the structure returned
*/
PGnotify *
PQnotifies(PGconn *conn)
{
Dlelem *e;
if (!conn) return NULL;
if (conn->status != CONNECTION_OK)
return NULL;
/* RemHead returns NULL if list is empy */
e = DLRemHead(conn->notifyList);
if (e)
return (PGnotify *) DLE_VAL(e);
else
return NULL;
}
/*
* PQgetline - gets a newline-terminated string from the backend.
*
* Chiefly here so that applications can use "COPY <rel> to stdout"
* and read the output string. Returns a null-terminated string in s.
*
* PQgetline reads up to maxlen-1 characters (like fgets(3)) but strips
* the terminating \n (like gets(3)).
*
* RETURNS:
* EOF if it is detected or invalid arguments are given
* 0 if EOL is reached (i.e., \n has been read)
* (this is required for backward-compatibility -- this
* routine used to always return EOF or 0, assuming that
* the line ended within maxlen bytes.)
* 1 in other cases
*/
int
PQgetline(PGconn *conn, char *s, int maxlen)
{
int c = '\0';
if (!conn)
return EOF;
if (!conn->Pfin || !s || maxlen <= 1)
return (EOF);
for (; maxlen > 1 &&
(c = pqGetc(conn->Pfin, conn->Pfdebug)) != '\n' &&
c != EOF;
--maxlen)
{
*s++ = c;
}
*s = '\0';
if (c == EOF)
{
return (EOF); /* error -- reached EOF before \n */
}
else if (c == '\n')
{
return (0); /* done with this line */
}
return (1); /* returning a full buffer */
}
/*
* PQputline -- sends a string to the backend.
*
* Chiefly here so that applications can use "COPY <rel> from stdin".
*
*/
void
PQputline(PGconn *conn, const char *s)
{
if (conn && (conn->Pfout)) {
(void) fputs(s, conn->Pfout);
fflush(conn->Pfout);
}
}
/*
* PQendcopy
* called while waiting for the backend to respond with success/failure
* to a "copy".
*
* RETURNS:
* 0 on success
* 1 on failure
*/
int
PQendcopy(PGconn *conn)
{
FILE *pfin,
*pfdebug;
bool valid = true;
if (!conn)
return (int) NULL;
pfin = conn->Pfin;
pfdebug = conn->Pfdebug;
if (pqGetc(pfin, pfdebug) == 'C')
{
char command[MAX_MESSAGE_LEN];
pqGets(command, MAX_MESSAGE_LEN, pfin, pfdebug); /* read command tag */
}
else
valid = false;
if (valid)
return (0);
else
{
sprintf(conn->errorMessage,
"Error return detected from backend, "
"but attempt to read the message failed.");
fprintf(stderr, "resetting connection\n");
PQreset(conn);
return (1);
}
}
/* simply send out max-length number of filler characters to fp */
static void
fill(int length, int max, char filler, FILE *fp)
{
int count;
char filltmp[2];
filltmp[0] = filler;
filltmp[1] = 0;
count = max - length;
while (count-- >= 0)
{
fprintf(fp, "%s", filltmp);
}
}
/*
* PQdisplayTuples()
* kept for backward compatibility
*/void
PQdisplayTuples(PGresult *res,
FILE *fp, /* where to send the output */
int fillAlign, /* pad the fields with spaces */
const char *fieldSep, /* field separator */
int printHeader,/* display headers? */
int quiet
)
{
#define DEFAULT_FIELD_SEP " "
int i,
j;
int nFields;
int nTuples;
int fLength[MAX_FIELDS];
if (fieldSep == NULL)
fieldSep = DEFAULT_FIELD_SEP;
/* Get some useful info about the results */
nFields = PQnfields(res);
nTuples = PQntuples(res);
if (fp == NULL)
fp = stdout;
/* Zero the initial field lengths */
for (j = 0; j < nFields; j++)
{
fLength[j] = strlen(PQfname(res, j));
}
/* Find the max length of each field in the result */
/* will be somewhat time consuming for very large results */
if (fillAlign)
{
for (i = 0; i < nTuples; i++)
{
for (j = 0; j < nFields; j++)
{
if (PQgetlength(res, i, j) > fLength[j])
fLength[j] = PQgetlength(res, i, j);
}
}
}
if (printHeader)
{
/* first, print out the attribute names */
for (i = 0; i < nFields; i++)
{
fputs(PQfname(res, i), fp);
if (fillAlign)
fill(strlen(PQfname(res, i)), fLength[i], ' ', fp);
fputs(fieldSep, fp);
}
fprintf(fp, "\n");
/* Underline the attribute names */
for (i = 0; i < nFields; i++)
{
if (fillAlign)
fill(0, fLength[i], '-', fp);
fputs(fieldSep, fp);
}
fprintf(fp, "\n");
}
/* next, print out the instances */
for (i = 0; i < nTuples; i++) {
for (j = 0; j < nFields; j++)
{
fprintf(fp, "%s", PQgetvalue(res, i, j));
if (fillAlign)
fill(strlen(PQgetvalue(res, i, j)), fLength[j], ' ', fp);
fputs(fieldSep, fp);
}
fprintf(fp, "\n");
}
if (!quiet)
fprintf(fp, "\nQuery returned %d row%s.\n", PQntuples(res),
(PQntuples(res) == 1) ? "" : "s");
fflush(fp);
}
/*
* PQprintTuples()
*
* kept for backward compatibility
*
*/
void
PQprintTuples(PGresult *res,
FILE *fout, /* output stream */
int PrintAttNames,/* print attribute names or not */
int TerseOutput, /* delimiter bars or not? */
int colWidth /* width of column, if 0, use variable
* width */
)
{
int nFields;
int nTups;
int i,
j;
char formatString[80];
char *tborder = NULL;
nFields = PQnfields(res);
nTups = PQntuples(res);
if (colWidth > 0)
{
sprintf(formatString, "%%s %%-%ds", colWidth);
}
else
sprintf(formatString, "%%s %%s");
if (nFields > 0)
{ /* only print rows with at least 1 field. */
if (!TerseOutput)
{
int width;
width = nFields * 14;
tborder = malloc(width + 1);
for (i = 0; i <= width; i++)
tborder[i] = '-';
tborder[i] = '\0';
fprintf(fout, "%s\n", tborder);
}
for (i = 0; i < nFields; i++)
{ if (PrintAttNames)
{
fprintf(fout, formatString,
TerseOutput ? "" : "|",
PQfname(res, i));
}
}
if (PrintAttNames)
{
if (TerseOutput)
fprintf(fout, "\n");
else
fprintf(fout, "|\n%s\n", tborder);
}
for (i = 0; i < nTups; i++)
{
for (j = 0; j < nFields; j++)
{
char *pval = PQgetvalue(res, i, j);
fprintf(fout, formatString,
TerseOutput ? "" : "|",
pval ? pval : "");
}
if (TerseOutput)
fprintf(fout, "\n");
else
fprintf(fout, "|\n%s\n", tborder);
}
}
}
static void
do_field(PQprintOpt *po, PGresult *res,
const int i, const int j, char *buf, const int fs_len,
char *fields[],
const int nFields, char *fieldNames[],
unsigned char fieldNotNum[], int fieldMax[],
const int fieldMaxLen, FILE *fout
)
{
char *pval,
*p,
*o;
int plen;
bool skipit;
plen = PQgetlength(res, i, j);
pval = PQgetvalue(res, i, j);
if (plen < 1 || !pval || !*pval)
{
if (po->align || po->expanded)
skipit = true;
else
{
skipit = false;
goto efield;
}
}
else
skipit = false;
if (!skipit)
{ for (p = pval, o = buf; *p; *(o++) = *(p++))
{
if ((fs_len == 1 && (*p == *(po->fieldSep))) || *p == '\\' || *p == '\n')
*(o++) = '\\';
if (po->align && (*pval == 'E' || *pval == 'e' ||
!((*p >= '0' && *p <= '9') ||
*p == '.' ||
*p == 'E' ||
*p == 'e' ||
*p == ' ' ||
*p == '-')))
fieldNotNum[j] = 1;
}
*o = '\0';
if (!po->expanded && (po->align || po->html3))
{
int n = strlen(buf);
if (n > fieldMax[j])
fieldMax[j] = n;
if (!(fields[i * nFields + j] = (char *) malloc(n + 1)))
{
perror("malloc");
exit(1);
}
strcpy(fields[i * nFields + j], buf);
}
else
{
if (po->expanded)
{
if (po->html3)
fprintf(fout,
"<tr><td align=left><b>%s</b></td>"
"<td align=%s>%s</td></tr>\n",
fieldNames[j],
fieldNotNum[j] ? "left" : "right",
buf);
else
{
if (po->align)
fprintf(fout,
"%-*s%s %s\n",
fieldMaxLen - fs_len, fieldNames[j], po->fieldSep,
buf);
else
fprintf(fout, "%s%s%s\n", fieldNames[j], po->fieldSep, buf);
}
}
else
{
if (!po->html3)
{
fputs(buf, fout);
efield:
if ((j + 1) < nFields)
fputs(po->fieldSep, fout);
else
fputc('\n', fout);
}
}
}
}
}
static char *
do_header(FILE *fout, PQprintOpt *po, const int nFields, int fieldMax[],
char *fieldNames[], unsigned char fieldNotNum[],
const int fs_len, PGresult *res){
int j; /* for loop index */
char *border = NULL;
if (po->html3)
fputs("<tr>", fout);
else
{
int j; /* for loop index */
int tot = 0;
int n = 0;
char *p = NULL;
for (; n < nFields; n++)
tot += fieldMax[n] + fs_len + (po->standard ? 2 : 0);
if (po->standard)
tot += fs_len * 2 + 2;
border = malloc(tot + 1);
if (!border)
{
perror("malloc");
exit(1);
}
p = border;
if (po->standard)
{
char *fs = po->fieldSep;
while (*fs++)
*p++ = '+';
}
for (j = 0; j < nFields; j++)
{
int len;
for (len = fieldMax[j] + (po->standard ? 2 : 0); len--; *p++ = '-');
if (po->standard || (j + 1) < nFields)
{
char *fs = po->fieldSep;
while (*fs++)
*p++ = '+';
}
}
*p = '\0';
if (po->standard)
fprintf(fout, "%s\n", border);
}
if (po->standard)
fputs(po->fieldSep, fout);
for (j = 0; j < nFields; j++)
{
char *s = PQfname(res, j);
if (po->html3)
{
fprintf(fout, "<th align=%s>%s</th>",
fieldNotNum[j] ? "left" : "right", fieldNames[j]);
}
else
{
int n = strlen(s);
if (n > fieldMax[j])
fieldMax[j] = n;
if (po->standard)
fprintf(fout,
fieldNotNum[j] ? " %-*s " : " %*s ",
fieldMax[j], s); else
fprintf(fout, fieldNotNum[j] ? "%-*s" : "%*s", fieldMax[j], s);
if (po->standard || (j + 1) < nFields)
fputs(po->fieldSep, fout);
}
}
if (po->html3)
fputs("</tr>\n", fout);
else
fprintf(fout, "\n%s\n", border);
return border;
}
static void
output_row(FILE *fout, PQprintOpt *po, const int nFields, char *fields[],
unsigned char fieldNotNum[], int fieldMax[], char *border,
const int row_index)
{
int field_index; /* for loop index */
if (po->html3)
fputs("<tr>", fout);
else if (po->standard)
fputs(po->fieldSep, fout);
for (field_index = 0; field_index < nFields; field_index++)
{
char *p = fields[row_index * nFields + field_index];
if (po->html3)
fprintf(fout, "<td align=%s>%s</td>",
fieldNotNum[field_index] ? "left" : "right", p ? p : "");
else
{
fprintf(fout,
fieldNotNum[field_index] ?
(po->standard ? " %-*s " : "%-*s") :
(po->standard ? " %*s " : "%*s"),
fieldMax[field_index],
p ? p : "");
if (po->standard || field_index + 1 < nFields)
fputs(po->fieldSep, fout);
}
if (p)
free(p);
}
if (po->html3)
fputs("</tr>", fout);
else if (po->standard)
fprintf(fout, "\n%s", border);
fputc('\n', fout);
}
/*
* PQprint()
*
* Format results of a query for printing.
*
* PQprintOpt is a typedef (structure) that containes
* various flags and options. consult libpq-fe.h for
* details
*
* Obsoletes PQprintTuples.
*/
voidPQprint(FILE *fout,
PGresult *res,
PQprintOpt *po
)
{
int nFields;
nFields = PQnfields(res);
if (nFields > 0)
{ /* only print rows with at least 1 field. */
int i,
j;
int nTups;
int *fieldMax = NULL; /* in case we don't use them */
unsigned char *fieldNotNum = NULL;
char *border = NULL;
char **fields = NULL;
char **fieldNames;
int fieldMaxLen = 0;
int numFieldName;
int fs_len = strlen(po->fieldSep);
int total_line_length = 0;
int usePipe = 0;
char *pagerenv;
char buf[8192 * 2 + 1];
nTups = PQntuples(res);
if (!(fieldNames = (char **) calloc(nFields, sizeof(char *))))
{
perror("calloc");
exit(1);
}
if (!(fieldNotNum = (unsigned char *) calloc(nFields, 1)))
{
perror("calloc");
exit(1);
}
if (!(fieldMax = (int *) calloc(nFields, sizeof(int))))
{
perror("calloc");
exit(1);
}
for (numFieldName = 0;
po->fieldName && po->fieldName[numFieldName];
numFieldName++)
;
for (j = 0; j < nFields; j++)
{
int len;
char *s =
(j < numFieldName && po->fieldName[j][0]) ?
po->fieldName[j] : PQfname(res, j);
fieldNames[j] = s;
len = s ? strlen(s) : 0;
fieldMax[j] = len;
len += fs_len;
if (len > fieldMaxLen)
fieldMaxLen = len;
total_line_length += len;
}
total_line_length += nFields * strlen(po->fieldSep) + 1;
if (fout == NULL)
fout = stdout;
if (po->pager && fout == stdout &&
isatty(fileno(stdin)) &&
isatty(fileno(stdout))) {
/* try to pipe to the pager program if possible */
#ifdef TIOCGWINSZ
if (ioctl(fileno(stdout), TIOCGWINSZ, &screen_size) == -1 ||
screen_size.ws_col == 0 ||
screen_size.ws_row == 0)
{
#endif
screen_size.ws_row = 24;
screen_size.ws_col = 80;
#ifdef TIOCGWINSZ
}
#endif
pagerenv = getenv("PAGER");
if (pagerenv != NULL &&
pagerenv[0] != '\0' &&
!po->html3 &&
((po->expanded &&
nTups * (nFields + 1) >= screen_size.ws_row) ||
(!po->expanded &&
nTups * (total_line_length / screen_size.ws_col + 1) *
(1 + (po->standard != 0)) >=
screen_size.ws_row -
(po->header != 0) *
(total_line_length / screen_size.ws_col + 1) * 2
- (po->header != 0) * 2 /* row count and newline */
)))
{
fout = popen(pagerenv, "w");
if (fout)
{
usePipe = 1;
pqsignal(SIGPIPE, SIG_IGN);
}
else
fout = stdout;
}
}
if (!po->expanded && (po->align || po->html3))
{
if (!(fields = (char **) calloc(nFields * (nTups + 1), sizeof(char *))))
{
perror("calloc");
exit(1);
}
}
else if (po->header && !po->html3)
{
if (po->expanded)
{
if (po->align)
fprintf(fout, "%-*s%s Value\n",
fieldMaxLen - fs_len, "Field", po->fieldSep);
else
fprintf(fout, "%s%sValue\n", "Field", po->fieldSep);
}
else
{
int len = 0;
for (j = 0; j < nFields; j++)
{
char *s = fieldNames[j];
fputs(s, fout);
len += strlen(s) + fs_len;
if ((j + 1) < nFields)
fputs(po->fieldSep, fout);
} fputc('\n', fout);
for (len -= fs_len; len--; fputc('-', fout));
fputc('\n', fout);
}
}
if (po->expanded && po->html3)
{
if (po->caption)
fprintf(fout, "<centre><h2>%s</h2></centre>\n", po->caption);
else
fprintf(fout,
"<centre><h2>"
"Query retrieved %d rows * %d fields"
"</h2></centre>\n",
nTups, nFields);
}
for (i = 0; i < nTups; i++)
{
if (po->expanded)
{
if (po->html3)
fprintf(fout,
"<table %s><caption align=high>%d</caption>\n",
po->tableOpt ? po->tableOpt : "", i);
else
fprintf(fout, "-- RECORD %d --\n", i);
}
for (j = 0; j < nFields; j++)
do_field(po, res, i, j, buf, fs_len, fields, nFields,
fieldNames, fieldNotNum,
fieldMax, fieldMaxLen, fout);
if (po->html3 && po->expanded)
fputs("</table>\n", fout);
}
if (!po->expanded && (po->align || po->html3))
{
if (po->html3)
{
if (po->header)
{
if (po->caption)
fprintf(fout,
"<table %s><caption align=high>%s</caption>\n",
po->tableOpt ? po->tableOpt : "",
po->caption);
else
fprintf(fout,
"<table %s><caption align=high>"
"Retrieved %d rows * %d fields"
"</caption>\n",
po->tableOpt ? po->tableOpt : "", nTups, nFields);
}
else
fprintf(fout, "<table %s>", po->tableOpt ? po->tableOpt : "");
}
if (po->header)
border = do_header(fout, po, nFields, fieldMax, fieldNames,
fieldNotNum, fs_len, res);
for (i = 0; i < nTups; i++)
output_row(fout, po, nFields, fields,
fieldNotNum, fieldMax, border, i);
free(fields);
if (border)
free(border);
}
if (po->header && !po->html3)
fprintf(fout, "(%d row%s)\n\n", PQntuples(res),
(PQntuples(res) == 1) ? "" : "s");
free(fieldMax);
free(fieldNotNum); free(fieldNames);
if (usePipe)
{
pclose(fout);
pqsignal(SIGPIPE, SIG_DFL);
}
if (po->html3 && !po->expanded)
fputs("</table>\n", fout);
}
}
/* ----------------
* PQfn - Send a function call to the POSTGRES backend.
*
* conn : backend connection
* fnid : function id
* result_buf : pointer to result buffer (&int if integer)
* result_len : length of return value.
* actual_result_len: actual length returned. (differs from result_len
* for varlena structures.)
* result_type : If the result is an integer, this must be 1,
* otherwise this should be 0
* args : pointer to a NULL terminated arg array.
* (length, if integer, and result-pointer)
* nargs : # of arguments in args array.
*
* RETURNS
* NULL on failure. PQerrormsg will be set.
* "G" if there is a return value.
* "V" if there is no return value.
* ----------------
*/
PGresult *
PQfn(PGconn *conn,
int fnid,
int *result_buf,
int *actual_result_len,
int result_is_int,
PQArgBlock *args,
int nargs)
{
FILE *pfin,
*pfout,
*pfdebug;
int id;
int i;
if (!conn)
return NULL;
pfin = conn->Pfin;
pfout = conn->Pfout;
pfdebug = conn->Pfdebug;
/* clear the error string */
conn->errorMessage[0] = '\0';
pqPuts("F ", pfout, pfdebug); /* function */
pqPutInt(fnid, 4, pfout, pfdebug); /* function id */
pqPutInt(nargs, 4, pfout, pfdebug); /* # of args */
for (i = 0; i < nargs; ++i)
{ /* len.int4 + contents */
pqPutInt(args[i].len, 4, pfout, pfdebug);
if (args[i].isint)
{
pqPutInt(args[i].u.integer, 4, pfout, pfdebug);
} else
{
pqPutnchar((char *) args[i].u.ptr, args[i].len, pfout, pfdebug);
}
}
pqFlush(pfout, pfdebug);
while ((id = pqGetc(pfin, pfdebug)) != 'V')
{
if (id == 'E')
{
pqGets(conn->errorMessage, ERROR_MSG_LENGTH, pfin, pfdebug);
}
else if (id == 'N')
{
/* print notice and go back to processing return
values */
if (pqGets(conn->errorMessage, ERROR_MSG_LENGTH,
pfin, pfdebug) == 1)
{
sprintf(conn->errorMessage,
"Notice return detected from backend, but "
"message cannot be read");
}
else
fprintf(stderr, "%s\n", conn->errorMessage);
continue;
}
else
sprintf(conn->errorMessage,
"PQfn: expected a 'V' from the backend. Got '%c' instead",
id);
return makeEmptyPGresult(conn, PGRES_FATAL_ERROR);
}
id = pqGetc(pfin, pfdebug);
for (;;)
{
int c;
switch (id)
{
case 'G': /* function returned properly */
pqGetInt(actual_result_len, 4, pfin, pfdebug);
if (result_is_int)
{
pqGetInt(result_buf, 4, pfin, pfdebug);
}
else
{
pqGetnchar((char *) result_buf, *actual_result_len,
pfin, pfdebug);
}
c = pqGetc(pfin, pfdebug); /* get the last '0' */
return makeEmptyPGresult(conn, PGRES_COMMAND_OK);
case 'E':
sprintf(conn->errorMessage,
"PQfn: returned an error");
return makeEmptyPGresult(conn, PGRES_FATAL_ERROR);
case 'N':
/* print notice and go back to processing return values */
if (pqGets(conn->errorMessage, ERROR_MSG_LENGTH, pfin, pfdebug)
== 1)
{
sprintf(conn->errorMessage,
"Notice return detected from backend, but message "
"cannot be read");
}
else
fprintf(stderr, "%s\n", conn->errorMessage); /* keep iterating */
break;
case '0': /* no return value */
return makeEmptyPGresult(conn, PGRES_COMMAND_OK);
default:
/* The backend violates the protocol. */
sprintf(conn->errorMessage,
"FATAL: PQfn: protocol error: id=%x\n", id);
return makeEmptyPGresult(conn, PGRES_FATAL_ERROR);
}
}
}
/* ====== accessor funcs for PGresult ======== */
ExecStatusType
PQresultStatus(PGresult *res)
{
if (!res)
{
fprintf(stderr, "PQresultStatus() -- pointer to PQresult is null");
return PGRES_NONFATAL_ERROR;
}
return res->resultStatus;
}
int
PQntuples(PGresult *res)
{
if (!res)
{
fprintf(stderr, "PQntuples() -- pointer to PQresult is null");
return (int) NULL;
}
return res->ntups;
}
int
PQnfields(PGresult *res)
{
if (!res)
{
fprintf(stderr, "PQnfields() -- pointer to PQresult is null");
return (int) NULL;
}
return res->numAttributes;
}
/*
returns NULL if the field_num is invalid
*/
char *
PQfname(PGresult *res, int field_num)
{
if (!res)
{
fprintf(stderr, "PQfname() -- pointer to PQresult is null");
return NULL;
}
if (field_num > (res->numAttributes - 1))
{
fprintf(stderr,
"PQfname: ERROR! name of field %d(of %d) is not available",
field_num, res->numAttributes - 1);
return NULL;
}
if (res->attDescs)
{ return res->attDescs[field_num].name;
}
else
return NULL;
}
/*
returns -1 on a bad field name
*/
int
PQfnumber(PGresult *res, const char *field_name)
{
int i;
char *field_case;
if (!res)
{
fprintf(stderr, "PQfnumber() -- pointer to PQresult is null");
return -1;
}
if (field_name == NULL ||
field_name[0] == '\0' ||
res->attDescs == NULL)
return -1;
field_case = strdup(field_name);
if (*field_case == '"')
{
strcpy(field_case, field_case + 1);
*(field_case + strlen(field_case) - 1) = '\0';
}
else
for (i = 0; field_case[i]; i++)
if (isupper(field_case[i]))
field_case[i] = tolower(field_case[i]);
for (i = 0; i < res->numAttributes; i++)
{
if (strcmp(field_name, res->attDescs[i].name) == 0)
{
free(field_case);
return i;
}
}
free(field_case);
return -1;
}
Oid
PQftype(PGresult *res, int field_num)
{
if (!res)
{
fprintf(stderr, "PQftype() -- pointer to PQresult is null");
return InvalidOid;
}
if (field_num > (res->numAttributes - 1))
{
fprintf(stderr,
"PQftype: ERROR! type of field %d(of %d) is not available",
field_num, res->numAttributes - 1);
}
if (res->attDescs)
{
return res->attDescs[field_num].adtid;
}
else
return InvalidOid;}
int2
PQfsize(PGresult *res, int field_num)
{
if (!res)
{
fprintf(stderr, "PQfsize() -- pointer to PQresult is null");
return (int2) NULL;
}
if (field_num > (res->numAttributes - 1))
{
fprintf(stderr,
"PQfsize: ERROR! size of field %d(of %d) is not available",
field_num, res->numAttributes - 1);
}
if (res->attDescs)
{
return res->attDescs[field_num].adtsize;
}
else
return 0;
}
char *
PQcmdStatus(PGresult *res)
{
if (!res)
{
fprintf(stderr, "PQcmdStatus() -- pointer to PQresult is null");
return NULL;
}
return res->cmdStatus;
}
/*
PQoidStatus -
if the last command was an INSERT, return the oid string
if not, return ""
*/
static char oidStatus[32] = {0};
const char *
PQoidStatus(PGresult *res)
{
if (!res)
{
fprintf(stderr, "PQoidStatus () -- pointer to PQresult is null");
return NULL;
}
oidStatus[0] = 0;
if (!res->cmdStatus)
return oidStatus;
if (strncmp(res->cmdStatus, "INSERT", 6) == 0)
{
char *p = res->cmdStatus + 7;
char *e;
for (e = p; *e != ' ' && *e;)
e++;
sprintf(oidStatus, "%.*s", e - p, p);
}
return oidStatus;
}
/*
PQcmdTuples -
if the last command was an INSERT/UPDATE/DELETE, return number of inserted/affected tuples, if not, return ""
*/
const char *
PQcmdTuples(PGresult *res)
{
if (!res)
{
fprintf(stderr, "PQcmdTuples () -- pointer to PQresult is null");
return NULL;
}
if (!res->cmdStatus)
return "";
if (strncmp(res->cmdStatus, "INSERT", 6) == 0 ||
strncmp(res->cmdStatus, "DELETE", 6) == 0 ||
strncmp(res->cmdStatus, "UPDATE", 6) == 0)
{
char *p = res->cmdStatus + 6;
if (*p == 0)
{
fprintf(stderr, "PQcmdTuples (%s) -- short input from server",
res->cmdStatus);
return NULL;
}
p++;
if (*(res->cmdStatus) != 'I') /* UPDATE/DELETE */
return (p);
while (*p != ' ' && *p)
p++; /* INSERT: skip oid */
if (*p == 0)
{
fprintf(stderr, "PQcmdTuples (INSERT) -- there's no # of tuples");
return NULL;
}
p++;
return (p);
}
return "";
}
/*
PQgetvalue:
return the value of field 'field_num' of row 'tup_num'
If res is binary, then the value returned is NOT a null-terminated
ASCII string, but the binary representation in the server's native
format.
if res is not binary, a null-terminated ASCII string is returned.
*/
char *
PQgetvalue(PGresult *res, int tup_num, int field_num)
{
if (!res)
{
fprintf(stderr, "PQgetvalue: pointer to PQresult is null\n");
return NULL;
}
else if (tup_num > (res->ntups - 1))
{
fprintf(stderr,
"PQgetvalue: There is no row %d in the query results. "
"The highest numbered row is %d.\n",
tup_num, res->ntups - 1);
return NULL;
}
else if (field_num > (res->numAttributes - 1))
{ fprintf(stderr,
"PQgetvalue: There is no field %d in the query results. "
"The highest numbered field is %d.\n",
field_num, res->numAttributes - 1);
return NULL;
}
return res->tuples[tup_num][field_num].value;
}
/* PQgetlength:
returns the length of a field value in bytes. If res is binary,
i.e. a result of a binary portal, then the length returned does
NOT include the size field of the varlena.
*/
int
PQgetlength(PGresult *res, int tup_num, int field_num)
{
if (!res)
{
fprintf(stderr, "PQgetlength() -- pointer to PQresult is null");
return (int) NULL;
}
if (tup_num > (res->ntups - 1) ||
field_num > (res->numAttributes - 1))
{
fprintf(stderr,
"PQgetlength: ERROR! field %d(of %d) of row %d(of %d) "
"is not available",
field_num, res->numAttributes - 1, tup_num, res->ntups);
}
if (res->tuples[tup_num][field_num].len != NULL_LEN)
return res->tuples[tup_num][field_num].len;
else
return 0;
}
/* PQgetisnull:
returns the null status of a field value.
*/
int
PQgetisnull(PGresult *res, int tup_num, int field_num)
{
if (!res)
{
fprintf(stderr, "PQgetisnull() -- pointer to PQresult is null");
return (int) NULL;
}
if (tup_num > (res->ntups - 1) ||
field_num > (res->numAttributes - 1))
{
fprintf(stderr,
"PQgetisnull: ERROR! field %d(of %d) of row %d(of %d) "
"is not available",
field_num, res->numAttributes - 1, tup_num, res->ntups);
}
if (res->tuples[tup_num][field_num].len == NULL_LEN)
return 1;
else
return 0;
}