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ea58f28ee8
Subject: [HACKERS] Patch for io routines
I am currently trying to improve on the front-backend communication
routines; and noticed that lots of code are duplicated for libpq and
the backend. This is a first patch that tries to share code between
the two, more to follow.
mjl
194 lines
4.2 KiB
C
194 lines
4.2 KiB
C
/*-------------------------------------------------------------------------
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*
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* FILE
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* fe-misc.c
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*
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* DESCRIPTION
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* miscellaneous useful functions
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* these routines are analogous to the ones in libpq/pqcomm.c
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*
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* Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.5 1997/03/16 18:51:29 scrappy Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include <stdlib.h>
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#include <stdio.h>
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#include "postgres.h"
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#include "libpq-fe.h"
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/* --------------------------------------------------------------------- */
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/* pqGetc:
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get a character from stream f
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if debug is set, also echo the character fetched
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*/
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int pqGetc(FILE* fin, FILE* debug)
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{
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int c;
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c = getc(fin);
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if (debug && c != EOF)
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fprintf(debug, "From backend> %c\n", c);
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return c;
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}
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/* --------------------------------------------------------------------- */
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/* pqPutnchar:
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send a string of exactly len length into stream f
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returns 1 if there was an error, 0 otherwise.
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*/
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int pqPutnchar(const char* s, int len, FILE *f, FILE *debug)
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{
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if (f == NULL)
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return 1;
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if(debug)
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fprintf(debug, "To backend> %s\n", s);
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if(fwrite(s, 1, len, f) != len)
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return 1;
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return 0;
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}
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/* --------------------------------------------------------------------- */
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/* pqGetnchar:
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get a string of exactly len length from stream f
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*/
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int pqGetnchar(char* s, int len, FILE *f, FILE *debug)
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{
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int cnt;
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if (f == NULL)
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return 1;
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cnt = fread(s, 1, len, f);
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s[cnt] = '\0';
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/* mjl: actually needs up to len+1 bytes, is this okay? XXX */
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if (debug)
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fprintf(debug, "From backend (%d)> %s\n", len, s);
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return 0;
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}
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/* --------------------------------------------------------------------- */
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/* pqGets:
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get a string of up to length len from stream f
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*/
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int pqGets(char* s, int len, FILE *f, FILE *debug)
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{
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int c;
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const char *str = s;
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if (f == NULL)
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return 1;
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while (len-- && (c = getc(f)) != EOF && c)
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*s++ = c;
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*s = '\0';
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/* mjl: actually needs up to len+1 bytes, is this okay? XXX */
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if (debug)
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fprintf(debug, "From backend> \"%s\"\n", str);
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return 0;
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}
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/* --------------------------------------------------------------------- */
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/* pgPutInt
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send an integer of 2 or 4 bytes to the file stream, compensate
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for host endianness.
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returns 0 if successful, 1 otherwise
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*/
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int pqPutInt(const int integer, int bytes, FILE* f, FILE *debug)
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{
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int retval = 0;
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switch(bytes)
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{
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case 2:
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retval = pqPutShort(integer, f);
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break;
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case 4:
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retval = pqPutLong(integer, f);
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break;
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default:
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fprintf(stderr, "** int size %d not supported\n", bytes);
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retval = 1;
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}
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if (debug) fprintf(debug, "To backend (%d#)> %d\n", bytes, integer);
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return retval;
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}
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/* --------------------------------------------------------------------- */
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/* pgGetInt
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read a 2 or 4 byte integer from the stream and swab it around
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to compensate for different endianness
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returns 0 if successful
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*/
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int pqGetInt(int* result, int bytes, FILE* f, FILE *debug)
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{
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int retval = 0;
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switch(bytes)
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{
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case 2:
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retval = pqGetShort(result, f);
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break;
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case 4:
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retval = pqGetLong(result, f);
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break;
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default:
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fprintf(stderr, "** int size %d not supported\n", bytes);
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retval = 1;
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}
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if (debug)
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fprintf(debug,"From backend (#%d)> %d\n", bytes, *result);
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return retval;
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}
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/* --------------------------------------------------------------------- */
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int pqPuts(const char* s, FILE *f, FILE *debug)
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{
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if (f == NULL)
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return 1;
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if (fputs(s, f) == EOF)
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return 1;
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fputc('\0', f); /* important to send an ending \0 since backend expects it */
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fflush(f);
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if (debug) {
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fprintf(debug, "To backend> %s\n", s);
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}
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return 0;
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}
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/* --------------------------------------------------------------------- */
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void pqFlush(FILE *f, FILE *debug)
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{
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if (f)
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fflush(f);
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if (debug)
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fflush(debug);
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}
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/* --------------------------------------------------------------------- */
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