make open file handles thread-safe. Fixes RT #57517 when using threads.

diff --git a/Fuse.xs b/Fuse.xs
index 285d1de..dab88bb 100755 (executable)
--- a/Fuse.xs
+++ b/Fuse.xs
@@ -21,6 +21,7 @@
 
 typedef struct {
        SV *callback[N_CALLBACKS];
+       HV *handles;
        tTHX self;
        int threaded;
        perl_mutex mutex;
@@ -51,6 +52,45 @@ tTHX master_interp = NULL;
 #define DEBUGf(a...)
 #endif
 
+#define FH_KEY(fi) sv_2mortal(newSViv((fi)->fh))
+#define FH_GETHANDLE(fi) S_fh_get_handle(aTHX_ aMY_CXT_ fi)
+#define FH_STOREHANDLE(fi,sv) S_fh_store_handle(aTHX_ aMY_CXT_ fi, sv)
+#define FH_RELEASEHANDLE(fi) S_fh_release_handle(aTHX_ aMY_CXT_ fi)
+
+SV *S_fh_get_handle(pTHX_ pMY_CXT_ struct fuse_file_info *fi) {
+       SV *val;
+       val = &PL_sv_undef;
+       if(fi->fh != 0) {
+               HE *he;
+               if((he = hv_fetch_ent(MY_CXT.handles, FH_KEY(fi), 0, 0))) {
+                       val = HeVAL(he);
+                       mg_get(val);
+               }
+       }
+       return val;
+}
+
+void S_fh_release_handle(pTHX_ pMY_CXT_ struct fuse_file_info *fi) {
+       if(fi->fh != 0) {
+               (void)hv_delete_ent(MY_CXT.handles, FH_KEY(fi), 0, G_DISCARD);
+               fi->fh = 0;
+       }
+}
+
+void S_fh_store_handle(pTHX_ pMY_CXT_ struct fuse_file_info *fi, SV *sv) {
+       if(SvOK(sv)) {
+#ifdef FUSE_USE_ITHREADS
+               if(MY_CXT.threaded) {
+                       SvSHARE(sv);
+               }
+#endif
+               MAGIC *mg = mg_find(sv, PERL_MAGIC_shared_scalar);
+               fi->fh = mg ? PTR2IV(mg->mg_ptr) : PTR2IV(sv);
+               (void)hv_store_ent(MY_CXT.handles, FH_KEY(fi), sv, 0);
+               mg_set(sv);
+       }
+}
+
 int _PLfuse_getattr(const char *file, struct stat *result) {
        int rv;
        FUSE_CONTEXT_PRE;
@@ -466,20 +506,9 @@ int _PLfuse_open (const char *file, struct fuse_file_info *fi) {
        /* Open called with filename, flags */
        rv = call_sv(MY_CXT.callback[14],G_ARRAY);
        SPAGAIN;
-       if(rv)
-       {
-               SV *sv;
-               if (rv > 1)
-               {
-                       sv = POPs;
-                       if (SvOK(sv))
-                       {
-                               /* We're holding on to the sv reference until
-                                * after exit of this function, so we need to
-                                * increment its reference count
-                                */
-                               fi->fh = SvREFCNT_inc(sv);
-                       }
+       if(rv) {
+               if(rv > 1) {
+                       FH_STOREHANDLE(fi,POPs);
                }
                rv = POPi;
        }
@@ -536,7 +565,7 @@ int _PLfuse_read (const char *file, char *buf, size_t buflen, off_t off, struct
        XPUSHs(sv_2mortal(newSVpv(temp, 0)));
        free(temp);
 #endif
-       XPUSHs(fi->fh==0 ? &PL_sv_undef : (SV *)fi->fh);
+       XPUSHs(FH_GETHANDLE(fi));
        PUTBACK;
        rv = call_sv(MY_CXT.callback[15],G_SCALAR);
        SPAGAIN;
@@ -585,7 +614,7 @@ int _PLfuse_write (const char *file, const char *buf, size_t buflen, off_t off,
        XPUSHs(sv_2mortal(newSVpv(temp, 0)));
        free(temp);
 #endif
-       XPUSHs(fi->fh==0 ? &PL_sv_undef : (SV *)fi->fh);
+       XPUSHs(FH_GETHANDLE(fi));
        PUTBACK;
        rv = call_sv(MY_CXT.callback[16],G_SCALAR);
        SPAGAIN;
@@ -654,7 +683,7 @@ int _PLfuse_flush (const char *file, struct fuse_file_info *fi) {
        SAVETMPS;
        PUSHMARK(SP);
        XPUSHs(sv_2mortal(newSVpv(file,0)));
-       XPUSHs(fi->fh==0 ? &PL_sv_undef : (SV *)fi->fh);
+       XPUSHs(FH_GETHANDLE(fi));
        PUTBACK;
        rv = call_sv(MY_CXT.callback[18],G_SCALAR);
        SPAGAIN;
@@ -680,7 +709,7 @@ int _PLfuse_release (const char *file, struct fuse_file_info *fi) {
        PUSHMARK(SP);
        XPUSHs(sv_2mortal(newSVpv(file,0)));
        XPUSHs(sv_2mortal(newSViv(flags)));
-       XPUSHs(fi->fh==0 ? &PL_sv_undef : (SV *)fi->fh);
+       XPUSHs(FH_GETHANDLE(fi));
        PUTBACK;
        rv = call_sv(MY_CXT.callback[19],G_SCALAR);
        SPAGAIN;
@@ -688,14 +717,7 @@ int _PLfuse_release (const char *file, struct fuse_file_info *fi) {
                rv = POPi;
        else
                rv = 0;
-       /* We're now finished with the handle that we were given, so
-        * we should decrement its count so that it can be freed.
-        */
-       if (fi->fh != 0)
-       {
-               SvREFCNT_dec((SV *)fi->fh);
-               fi->fh = 0;
-       }
+       FH_RELEASEHANDLE(fi);
        FREETMPS;
        LEAVE;
        PUTBACK;
@@ -714,7 +736,7 @@ int _PLfuse_fsync (const char *file, int datasync, struct fuse_file_info *fi) {
        PUSHMARK(SP);
        XPUSHs(sv_2mortal(newSVpv(file,0)));
        XPUSHs(sv_2mortal(newSViv(flags)));
-       XPUSHs(fi->fh==0 ? &PL_sv_undef : (SV *)fi->fh);
+       XPUSHs(FH_GETHANDLE(fi));
        PUTBACK;
        rv = call_sv(MY_CXT.callback[20],G_SCALAR);
        SPAGAIN;
@@ -991,10 +1013,12 @@ perl_fuse_main(...)
        CODE:
        debug = SvIV(ST(0));
        MY_CXT.threaded = SvIV(ST(1));
+       MY_CXT.handles = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV())));
        if(MY_CXT.threaded) {
 #ifdef FUSE_USE_ITHREADS
                master_interp = aTHX;
                MUTEX_INIT(&MY_CXT.mutex);
+               SvSHARE(MUTABLE_SV(MY_CXT.handles));
 #else
                fprintf(stderr,"FUSE warning: Your script has requested multithreaded "
                               "mode, but your perl was not built with a supported "