# DL.callback as free function causes errors **URL:** \ **Category:** Development\ **Created:** [March 18, 2007, 2:43am UTC](https://www.ruby-forum.com/t/dl-callback-as-free-function-causes-errors/89170 "2007-03-18T02:43:28Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![sheepman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/d07c76/32.png) [@sheepman](https://www.ruby-forum.com/u/sheepman)\ **Post date:** [March 18, 2007, 2:43am UTC](https://www.ruby-forum.com/t/dl-callback-as-free-function-causes-errors/89170/1 "2007-03-18T02:43:28Z")
こんにちは、sheepman です。 DL::PtrData オブジェクトでは ruby が GC をする時に呼ぶ free function を指定することができます。 で、たとえば regex ライブラリだと regfree したあとに、 free を呼びたいので、以下のような DL.callback を使ったコードを 書きたくなります。 require ‘dl’ include DL h = dlopen(nil) regcomp = h.sym(‘regcomp’, ‘IPSI’) regfree = h.sym(‘regfree’, ‘0P’) free = callback(‘0P’){|ptr| regfree[ptr] FREE[ptr] } 100000.times do |i| ptr = PtrData.malloc(50, free) regcomp.call(ptr, ‘123’, 0) end しかし、これは segv ã—ã¾ã™ã€‚åŽŸå› ã‚’æ­£ç¢ºã«è¿½ã†ã“ã¨ãŒã§ãã¦ã„ãªã„ã®ã§ã™ãŒã€ おそらく GC の真最中にブロックが呼ばれることで起きているんだと思います。 というわけで、DL::Symbol オブジェクトにcallbackかどうかのフラグを持たせて、 callback は PtrData の free 関数として指定できないようにパッチを書いてみました。 segv ã—ã¦ã„ã‚‹åŽŸå› ãŒé•ã£ã¦ã„ã‚‹ãªã‚‰ã€ã“ã®ãƒ‘ãƒƒãƒã¯ç„¡ç”¨ã®ã‚‚ã®ã«ãªã‚Šã¾ã™ã€‚ ---
**Author:** ![sheepman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/d07c76/32.png) [@sheepman](https://www.ruby-forum.com/u/sheepman)\ **Post date:** [March 18, 2007, 3:47am UTC](https://www.ruby-forum.com/t/dl-callback-as-free-function-causes-errors/89170/2 "2007-03-18T03:47:33Z")
e$B$J$+$@$G$9!#e(B At Sun, 18 Mar 2007 10:43:11 +0900, sheepman wrote in [ruby-dev:30620]: > DL::PtrData e$B%\*%V%8%’%/%H$G$Oe(B ruby e$B$,e(B GC e$B$r$9$k;~$K8F$Ve(B > free function e$B$r;XDj$9$k$3$H$,$G$-$^$9!#e(B e$BJ9$/$+$i$K4m81$=$&$J5!G=$G$9$,!#e(B > e$B$7$+$7!"$3$l$Oe(B segv e$B$7$^$9!#860x$r@53N$KDI$&$3$H$,$G$-$F$$$J$$$N$G$9$,!"e(B > e$B$\*$=$i$/e(B GC e$B$N??:GCf$K%V%m%C%/$,8F$P$l$k$3$H$G5/$-$F$$$k$s$@$H;W$$$^$9!#e(B > > e$B$H$$$&$o$1$G!"e(BDL::Symbol e$B%\*%V%8%’%/%H$Ke(Bcallbacke$B$+$I$&$+$N%U%i%0$r;}$?$;$F!"e(B > callback e$B$Oe(B PtrData e$B$Ne(B free e$B4X?t$H$7$F;XDj$G$-$J$$$h$&$K%Q%C%A$r=q$$$F$\_$^$7$?!#e(B callbacke$B$Oe(Bfinalizere$B$KJQ49$7$FEPO?$9$k!"$H$$$&$N$O$I$&$G$7$g$&$+!#e(B finalizere$B$Oe(BGCe$B=\*N;D\>8e$K\ **Author:** ![sheepman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/d07c76/32.png) [@sheepman](https://www.ruby-forum.com/u/sheepman)\ **Post date:** [March 18, 2007, 10:31am UTC](https://www.ruby-forum.com/t/dl-callback-as-free-function-causes-errors/89170/3 "2007-03-18T10:31:55Z") e$B$3$s$P$s$O!"e(Bsheepman e$B$G$9!#e(B On Sun, 18 Mar 2007 11:46:59 +0900 Nobuyoshi N. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > callbacke$B$Oe(Bfinalizere$B$KJQ49$7$FEPO?$9$k!"$H$$$&$N$O$I$&$G$7$g$&$+!#e(B > finalizere$B$Oe(BGCe$B=\*N;D\>8e$K\ **Author:** ![sheepman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/d07c76/32.png) [@sheepman](https://www.ruby-forum.com/u/sheepman)\ **Post date:** [March 20, 2007, 3:07pm UTC](https://www.ruby-forum.com/t/dl-callback-as-free-function-causes-errors/89170/4 "2007-03-20T15:07:48Z") sheepman wrote: > DL::PtrData e$B%\*%V%8%’%/%H$G$Oe(B ruby e$B$,e(B GC e$B$r$9$k;~$K8F$Ve(B > free function e$B$r;XDj$9$k$3$H$,$G$-$^$9!#e(B > > e$B$G!"$?$H$($Pe(B regex e$B%i%$%V%i%j$@$He(B regfree e$B$7$?$"$H$K!"e(B > free e$B$r8F$S$?$$$N$G!"0J2\<$N$h$&$Je(B DL.callback e$B$r;H$C$?%3!\<%I$re(B > e$B=q$-$?$/$J$j$^$9!#e(B e$B$J$k$[$I!#e(B > e$B$H$$$&$o$1$G!"e(BDL::Symbol e$B%\*%V%8%’%/%H$Ke(Bcallbacke$B$+$I$&$+$N%U%i%0$r;}$?$;$F!“e(B > callback e$B$Oe(B PtrData e$B$Ne(B free e$B4X?t$H$7$F;XDj$G$-$J$$$h$&$K%Q%C%A$r=q$$$F$\_$^$7$?!#e(B > segv e$B$7$F$$$k860x$,0c$C$F$$$k$J$i!”$3$N%Q%C%A$OL5MQ$N$b$N$K$J$j$^$9!#e(B e$B9\*$/2r7h$G$-$k$^$G$O!"$R$H$^$:%Q%C%A$r\