--- Coro-Mysql/Mysql.xs	2011/02/17 02:05:15	1.7
+++ Coro-Mysql/Mysql.xs	2013/08/03 02:11:27	1.11
@@ -1,4 +1,4 @@
-#include <sys/errno.h>
+#include <errno.h>
 #include <unistd.h>
 #include <fcntl.h>
 
@@ -23,11 +23,13 @@
 
 #include "violite.h"
 
-#define DESC_OFFSET 22
-
 #define CoMy_MAGIC 0x436f4d79
 
 typedef struct {
+#if DESC_IS_PTR
+  char desc[30];
+  const char *old_desc;
+#endif
   int magic;
   SV *corohandle_sv, *corohandle;
   int bufofs, bufcnt;
@@ -37,10 +39,15 @@
   char buf[VIO_READ_BUFFER_SIZE];
 } ourdata;
 
-#define OURDATAPTR (*((ourdata **)((vio)->desc + DESC_OFFSET)))
+#if DESC_IS_PTR
+# define OURDATAPTR (*(ourdata **)&((vio)->desc))
+#else
+# define DESC_OFFSET 22
+# define OURDATAPTR (*((ourdata **)((vio)->desc + DESC_OFFSET)))
+#endif
 
-static int
-our_read (Vio *vio, xgptr p, int len)
+static xlen
+our_read (Vio *vio, xgptr p, xlen len)
 {
   ourdata *our = OURDATAPTR;
 
@@ -94,8 +101,8 @@
   return len;
 }
 
-static int
-our_write (Vio *vio, const xgptr p, int len)
+static xlen
+our_write (Vio *vio, cxgptr p, xlen len)
 {
   char *ptr = (char *)p;
   my_bool dummy;
@@ -167,6 +174,10 @@
   SvREFCNT_dec (our->corohandle);
   SvREFCNT_dec (our->corohandle_sv);
 
+#if DESC_IS_PTR
+  vio->desc = our->old_desc;
+#endif
+
   Safefree (our);
 
   vio->read     = vio_read;
@@ -215,13 +226,18 @@
 }
 
 void
-_patch (IV sock, int fd, SV *corohandle_sv, SV *corohandle)
+_patch (IV sock, int fd, unsigned long client_version, SV *corohandle_sv, SV *corohandle)
 	CODE:
 {
 	MYSQL *my = (MYSQL *)sock;
         Vio *vio = my->net.vio;
         ourdata *our;
 
+        /* matching versions are required but not sufficient */
+        if (client_version != mysql_get_client_version ())
+          croak ("DBD::mysql linked against different libmysqlclient library than Coro::Mysql (%lu vs. %lu).",
+                 client_version, mysql_get_client_version ());
+
         if (fd != my->net.fd)
           croak ("DBD::mysql fd and libmysql disagree - library mismatch, unsupported transport or API changes?");
 
@@ -229,7 +245,7 @@
           croak ("DBD::mysql fd and vio-sd disagree - library mismatch, unsupported transport or API changes?");
 
         if (vio->vioclose != vio_close)
-          croak ("vio.write has unexpected content - library mismatch, unsupported transport or API changes?");
+          croak ("vio.vioclose has unexpected content - library mismatch, unsupported transport or API changes?");
 
         if (vio->write != vio_write)
           croak ("vio.write has unexpected content - library mismatch, unsupported transport or API changes?");
@@ -249,8 +265,13 @@
             ev_io_init (&(our->ww), iocb, vio->sd, EV_WRITE);
           }
 #endif
-
+#if DESC_IS_PTR
+        our->old_desc = vio->desc;
+        strncpy (our->desc, vio->desc, sizeof (our->desc));
+        our->desc [sizeof (our->desc) - 1] = 0;
+#else
         vio->desc [DESC_OFFSET - 1] = 0;
+#endif
         OURDATAPTR = our;
 
         vio->vioclose = our_close;