om: "Martin J. Laubach" <mjl@CSlab.tuwien.ac.at>

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

src/include/libpq/pqcomm.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: pqcomm.h,v 1.8 1997/03/12 21:22:19 scrappy Exp $
+ * $Id: pqcomm.h,v 1.9 1997/03/16 18:50:47 scrappy Exp $
  *
  * NOTES
  *    Some of this should move to libpq.h
@@ -123,6 +123,11 @@ typedef struct Port {
 extern FILE *Pfout, *Pfin;
 extern int PQAsyncNotifyWaiting;
 
+/* in pqcompriv.c */
+int pqGetShort(int *, FILE *);
+int pqGetLong(int *, FILE *);
+int pqPutShort(int, FILE *);
+int pqPutLong(int, FILE *);
 /*
  * prototypes for functions in pqpacket.c
  */

src/interfaces/libpq/Makefile

@@ -7,7 +7,7 @@
 #
 #
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/interfaces/libpq/Makefile,v 1.29 1997/03/15 19:17:03 scrappy Exp $
+#    $Header: /cvsroot/pgsql/src/interfaces/libpq/Makefile,v 1.30 1997/03/16 18:51:13 scrappy Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -24,7 +24,7 @@ CFLAGS+= $(KRBFLAGS)
 endif
 
 OBJS= fe-auth.o fe-connect.o fe-exec.o fe-misc.o fe-lobj.o \
-         dllist.o pqsignal.o 
+      dllist.o pqsignal.o pqcomprim.o
 
 # Shared library stuff
 shlib := 
@@ -58,7 +58,10 @@ fe-lobj.o: ../backend/fmgr.h
 # We need to compile this with special options for shared libs,
 # so we can't use the object in ../backend
 dllist.c:	../backend/lib/dllist.c
-	-ln ../backend/lib/dllist.c
+	-ln -s ../backend/lib/dllist.c
+
+pqcomprim.c:	    ../backend/libpq/pqcomprim.c
+	-ln -s ../backend/libpq/pqcomprim.c
 
 # The following rules cause dependencies in the backend directory to 
 # get made if they don't exist, but don't cause them to get remade if they

src/interfaces/libpq/fe-misc.c

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.4 1996/12/31 07:29:17 bryanh Exp $
+ *    $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.5 1997/03/16 18:51:29 scrappy Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -23,76 +23,73 @@
 
 #include "libpq-fe.h"
 
+/* --------------------------------------------------------------------- */
 /* pqGetc:
    get a character from stream f
 
    if debug is set, also echo the character fetched
 */
-int
-pqGetc(FILE* fin, FILE* debug)
+int pqGetc(FILE* fin, FILE* debug)
 {
   int c;
 
   c = getc(fin);
+
   if (debug && c != EOF)
     fprintf(debug, "From backend> %c\n", c);
+    
   return c;
 }
 
+/* --------------------------------------------------------------------- */
 /* pqPutnchar:
    send a string of exactly len length into stream f 
 
    returns 1 if there was an error, 0 otherwise.
 */
-int
-pqPutnchar(const char* s, int len, FILE *f, FILE *debug)
+int pqPutnchar(const char* s, int len, FILE *f, FILE *debug)
 {
-    int status;
-
     if (f == NULL)
 	return 1;
 
-    if (debug) fputs("To backend>", debug);
-    while (len--) {
-	status = fputc(*s,f);
-	if (debug)
-	    fputc(*s,debug);
-	s++;
-	if (status == EOF)
+   if(debug)
+      fprintf(debug, "To backend> %s\n", s);
+
+   if(fwrite(s, 1, len, f) != len)
 	    return 1;
-    }
-    if (debug) fputc('\n', debug);
+
     return 0;
 }
 
+/* --------------------------------------------------------------------- */
 /* pqGetnchar:
    get a string of exactly len length from stream f 
 */
-int
-pqGetnchar(char* s, int len, FILE *f, FILE *debug)
+int pqGetnchar(char* s, int len, FILE *f, FILE *debug)
 {
-  int c;
+   int cnt;
 
   if (f == NULL)
     return 1;
   
-  while (len-- && (c = getc(f)) != EOF)
-    *s++ = c;
-  *s = '\0';
+   cnt = fread(s, 1, len, f);
+   s[cnt] = '\0';
+   /* mjl: actually needs up to len+1 bytes, is this okay? XXX */
+
+   if (debug)
+      fprintf(debug, "From backend (%d)> %s\n", len, s);
 
-  if (debug) {
-      fprintf(debug, "From backend> %s\n", s);
-  }
   return 0;
 }
 
+/* --------------------------------------------------------------------- */
 /* pqGets:
    get a string of up to length len from stream f
 */
-int
-pqGets(char* s, int len, FILE *f, FILE *debug)
+int pqGets(char* s, int len, FILE *f, FILE *debug)
 {
   int c;
+   const char *str = s;
 
   if (f == NULL)
     return 1;
@@ -100,104 +97,98 @@ pqGets(char* s, int len, FILE *f, FILE *debug)
   while (len-- && (c = getc(f)) != EOF && c)
     *s++ = c;
   *s = '\0';
+   /* mjl: actually needs up to len+1 bytes, is this okay? XXX */
+
+   if (debug)
+      fprintf(debug, "From backend> \"%s\"\n", str);
 
-  if (debug) {
-      fprintf(debug, "From backend> %s\n", s);
-  }
   return 0;
 }
 
-
+/* --------------------------------------------------------------------- */
 /* pgPutInt
-   send an integer of up to 4 bytesto the file stream
-   do this one byte at at time. 
-   This insures that machines with different ENDIANness can talk to each other
-   get a n-byte integer from the stream into result 
+   send an integer of 2 or 4 bytes to the file stream, compensate
+   for host endianness.
    returns 0 if successful, 1 otherwise
 */
-int
-pqPutInt(const int integer, int bytes, FILE* f, FILE *debug)
+int pqPutInt(const int integer, int bytes, FILE* f, FILE *debug)
 {
-    int i;
-    int status;
-
-    i = integer;
-
-    if (bytes > 4)
-	bytes = 4;
-
-    while (bytes--) {
-	status = fputc(i & 0xff, f);
-	i >>= 8;
-	if (status == EOF) {
-	    return 1;
-	}
-    }
-    if (debug) fprintf(debug, "To backend (#)> %d\n", integer);
-    return 0;
+    int retval = 0;
+
+    switch(bytes)
+    	{
+    	case 2:
+      	    retval = pqPutShort(integer, f);
+      	    break;
+    	case 4:
+      	    retval = pqPutLong(integer, f);
+      	    break;
+    	default:
+    	    fprintf(stderr, "** int size %d not supported\n", bytes);
+    	    retval = 1;
+    	}
+
+    if (debug) fprintf(debug, "To backend (%d#)> %d\n", bytes, integer);
+
+    return retval;
 }
 
+/* --------------------------------------------------------------------- */
 /* pgGetInt 
-   reconstructs the integer one byte at a time.
-   This insures that machines with different ENDIANness can talk to each other
-   get a n-byte integer from the stream into result 
+   read a 2 or 4 byte integer from the stream and swab it around
+   to compensate for different endianness
    returns 0 if successful 
 */
-int
-pqGetInt(int* result, int bytes, FILE* f, FILE *debug)
+int pqGetInt(int* result, int bytes, FILE* f, FILE *debug)
 {
-  int c;
-  int p;
-  int n;
-
-  if (f == NULL)
-    return 1;
+    int retval = 0;
   
-  p = 0;
-  n = 0;
-  while (bytes && (c = getc(f)) != EOF)
+    switch(bytes)
     {
-      n |= (c & 0xff) << p;
-      p += 8;
-      bytes--;
+      	case 2:
+      	    retval = pqGetShort(result, f);
+    	    break;
+    	case 4:
+    	    retval = pqGetLong(result, f);
+    	    break;
+    	 default:
+    	    fprintf(stderr, "** int size %d not supported\n", bytes);
+    	    retval = 1;
     }
 
-  if (bytes != 0)
-    return 1;
-
-  *result = n;
   if (debug)
-      fprintf(debug,"From backend (#)> %d\n",*result);
-  return 0;
-}
+    	fprintf(debug,"From backend (#%d)> %d\n", bytes, *result);
 
+    return retval;
+}
 
-int
-pqPuts(const char* s, FILE *f, FILE *debug)
+/* --------------------------------------------------------------------- */
+int pqPuts(const char* s, FILE *f, FILE *debug)
 {
   if (f == NULL)
     return 1;
   
-  if (fputs(s,f) == EOF)
+   if (fputs(s, f) == EOF)
     return 1;
 
-  fputc('\0',f); /* important to send an ending EOF since backend expects it */
+   fputc('\0', f); /* important to send an ending \0 since backend expects it */
   fflush(f);
 
   if (debug) {
       fprintf(debug, "To backend> %s\n", s);
   }
+  
   return 0;
 }
 
-
-void
-pqFlush(FILE *f, FILE *debug)
+/* --------------------------------------------------------------------- */
+void pqFlush(FILE *f, FILE *debug)
 {
     if (f)
 	fflush(f);
+
     if (debug)
 	fflush(debug);
 }
 
-
+/* --------------------------------------------------------------------- */