FreeTDS Development Group

["Brandon M. Reynolds" <bmr AT comtime.com>]

Brian Bruns wrote:
> 
> Actually, BUFSIZ is used only once in the code which is to do a malloc.
> That needs to be cleaned up but it's not causing any problems.

Well, a little more than once, tds/login.c is probably OK, not sure
about
tds/read.c.  What's that stuff under the server directory get used for
anyway?

[w3]freetds> grep -r BUFSIZ *
samples/debug.c:unsigned char    buf[BUFSIZ];
samples/debug.c:        while ((len = read(fd, buf, BUFSIZ)) > 0) {
src/server/login.c:unsigned char buf[BUFSIZ];
src/server/login.c:     tds = tds_alloc_socket(BUFSIZ);
src/server/query.c:static unsigned char query[BUFSIZ];
src/tds/login.c:        tds = tds_alloc_socket(BUFSIZ);
src/tds/read.c:unsigned char buf[BUFSIZ];

> I think you've hit on the real problem here:
> 
> > +     if (tds->out_pos>=8192) {
> 
> It appears that TDS 7.0 does not allow multiple query packets!?
> 
> I'm guessing if you made the query larger than 8192 bytes this would again
> fail.  I'll try to throw a permanent patch together (this one will break
> TDS 4.2 and 5.0) if somebody is willing to test it.

Here's what I changed it to:
-       if (tds->out_pos>=512) {
+       if (!IS_TDS70(tds) && tds->out_pos>=512) {

I think SQL Server 7 can't handle queries longer than 8k, but I'm not
sure.

While we're at it there's a couple of other things I'd like added...
1.  I changed the dbbuf to be dynamic.

2.  In dbbind(), I changed one line to prevent dereferencing a NULL
pointer.

3.  I Changed dbsqlexec so that you don't have to do a fetch and make it
fail in
    order to not have your program crash!

I have tested these changes for some time and they work for me.  I have
programs written in C and PHP.

Notice: these are not acurate diff's because I can't keep up with the
CVS!

--- freetds/include/sybdb.h     Sat Oct  7 15:32:32 2000
+++ freetds.good/include/sybdb.h        Fri Oct  6 11:28:21 2000
    int             noautofree;
    int             more_results; /* boolean.  Are we expecting results?
*/
    BYTE           *user_data;   /* see dbsetuserdata() and
dbgetuserdata() */
-   unsigned char   dbbuf[8192]; /* XXX should be
dynamic                   */
+   unsigned char  *dbbuf; /* is dynamic!                   */
+   int             dbbufsz;
    int             empty_res_hack;
    TDS_INT         text_size;
    TDS_INT         text_sent;
@@ -293,6 +296,7 @@
 extern RETCODE    dbinit();
 extern LOGINREC  *dblogin();
 extern RETCODE    DBSETLPACKET(LOGINREC *login, short packet_size);
+extern RETCODE    DBSETLCHARSET(LOGINREC *login, char *charset);
 extern RETCODE    DBSETLPWD(LOGINREC *login, char *password);
 extern RETCODE    DBSETLUSER(LOGINREC *login, char *username);
 extern RETCODE    DBSETLHOST(LOGINREC *login, char *hostname);

--- freetds/src/dblib/dblib.c   Sun Oct  8 22:19:09 2000
+++ freetds.good/src/dblib/dblib.c      Fri Oct  6 11:30:22 2000
@@ -449,11 +448,13 @@
        }

    dbproc->tds_socket = (void *) tds_connect(login->tds_login);
-   dbproc->dbbuf[0]='\0'; /* initialize query buffer */
+   dbproc->dbbuf = NULL;
+   dbproc->dbbufsz = 0;

 RETCODE        dbcmd(DBPROCESS *dbproc, char *cmdstring)
 {
-       /* here is one of those large static buffers that should be
malloced
-       ** but in the interest of time i kludged :)   */
-       strcat(dbproc->dbbuf,cmdstring);
-       return SUCCEED;
+  if(dbproc->dbbufsz == 0) {
+    if((dbproc->dbbuf =
+       (unsigned char *)malloc(strlen(cmdstring)+1)) == NULL) {
+      return FAIL;
+    }
+    strcpy(dbproc->dbbuf,cmdstring);
+    dbproc->dbbufsz = strlen(cmdstring) + 1;
+  } else {
+    int newsz;
+    void *p;
+
+    newsz = strlen(cmdstring) + dbproc->dbbufsz;
+    if((p=realloc(dbproc->dbbuf,newsz)) == NULL) {
+      return FAIL;
+    }
+    dbproc->dbbuf = (unsigned char *)p;
+    strcat(dbproc->dbbuf,cmdstring);
+    dbproc->dbbufsz = newsz;
+  }
+
+  return SUCCEED;
 }
 RETCODE dbsqlexec(DBPROCESS *dbproc)
 {
@@ -478,7 +507,9 @@
    tds = (TDSSOCKET *) dbproc->tds_socket;
    if (!tds || !tds->s) return FAIL;

-   if (tds->res_info && tds->res_info->more_results)
+   if (tds->res_info && tds->res_info->more_results || tds->state ==
TDS_PENDING)
    /* if (dbproc->more_results &&
tds_is_end_of_results(dbproc->tds_socket)) */
    {
       dbresults(dbproc);

@@ -833,8 +851,9 @@
       tds     = (TDSSOCKET *) dbproc->tds_socket;
       resinfo = tds->res_info;
    }

-   okay = okay && ((column >= 1) && (column <= resinfo->num_cols));
+   okay = okay && ((column >= 1) && (column <=
(resinfo?resinfo->num_cols:0)));

    if (okay)
    {
@@ -1618,7 +1637,13 @@

 void dbfreebuf(DBPROCESS *dbproc)
 {
-   dbproc->dbbuf[0] = '\0';
+  // bmr: 10-06-2000
+  //   dbproc->dbbuf[0] = '\0';
+  if(dbproc->dbbuf) {
+    free(dbproc->dbbuf);
+    dbproc->dbbuf = NULL;
+  }
+  dbproc->dbbufsz = 0;
 } /* dbfreebuf()  */

 RETCODE dbclropt(DBPROCESS *dbproc,int option, char *param)
@@ -1895,7 +1920,9 @@
       }
       if (! dbproc->noautofree)
       {
-         dbproc->dbbuf[0]='\0';
+       dbfreebuf(dbproc);
       }
       result = SUCCEED;
    }

-- 
Brandon Reynolds                  Phone: (330) 644-3059
Systems Engineer                    Fax: (330) 644-8110
Commercial Timesharing Inc.      E-mail: bmr AT comtime.com