From ee289c241577a3553bfd73211cd81e137ab4fe40 Mon Sep 17 00:00:00 2001 From: cinap_lenrek Date: Sat, 1 May 2021 19:58:58 +0200 Subject: [PATCH] lib9p: remove Srv.srvfd, make postsrv() and threadpostsrv() return the mountable file descriptor, update documentation Now that we have these new functions, we can also make them return an error instead of calling sysfatal() like postmountsrv(). Remove the confusing Srv.srvfd, as it is only temporarily used and return it from postsrv() instead. --- sys/include/9p.h | 5 +-- sys/man/2/9p | 77 ++++++++++++++++++----------------- sys/src/cmd/aux/wacom.c | 3 +- sys/src/lib9p/listen.c | 2 +- sys/src/lib9p/mount.c | 11 +++-- sys/src/lib9p/post.c | 38 ++++++++--------- sys/src/lib9p/share.c | 11 ++--- sys/src/lib9p/threadpostsrv.c | 4 +- 8 files changed, 77 insertions(+), 74 deletions(-) diff --git a/sys/include/9p.h b/sys/include/9p.h index 1a51ffeab..bfbe0d7ec 100644 --- a/sys/include/9p.h +++ b/sys/include/9p.h @@ -214,7 +214,6 @@ struct Srv { int infd; int outfd; - int srvfd; char* keyspec; /* below is implementation-specific; don't use */ @@ -243,13 +242,13 @@ void srvforker(void (*)(void*), void*, int); void threadsrvforker(void (*)(void*), void*, int); void srv(Srv*); -void postsrv(Srv*, char*); +int postsrv(Srv*, char*); void postmountsrv(Srv*, char*, char*, int); void postsharesrv(Srv*, char*, char*, char*); void listensrv(Srv*, char*); void threadsrv(Srv*); -void threadpostsrv(Srv*, char*); +int threadpostsrv(Srv*, char*); void threadpostmountsrv(Srv*, char*, char*, int); void threadpostsharesrv(Srv*, char*, char*, char*); void threadlistensrv(Srv *s, char *addr); diff --git a/sys/man/2/9p b/sys/man/2/9p index d68fbaa2c..4fb831d09 100644 --- a/sys/man/2/9p +++ b/sys/man/2/9p @@ -63,7 +63,6 @@ typedef struct Srv { int infd; int outfd; - int srvfd; void (*forker)(void (*fn)(void*), void *arg, int flags); } Srv; @@ -73,12 +72,12 @@ typedef struct Srv { .ft L .ta \w'\fLvoid* 'u void srv(Srv *s) -void postsrv(Srv *s, char *name); +int postsrv(Srv *s, char *name); void postmountsrv(Srv *s, char *name, char *mtpt, int flag) void postsharesrv(Srv *s, char *name, char *mtpt, char *desc) void listensrv(Srv *s, char *addr) void threadsrv(Srv *s) -void threadpostsrv(Srv *s, char *name); +int threadpostsrv(Srv *s, char *name); void threadpostmountsrv(Srv *s, char *name, char *mtpt, int flag) void threadpostsharesrv(Srv *s, char *name, char *mtpt, char *desc) void threadlistensrv(Srv *s, char *addr) @@ -193,14 +192,26 @@ or (see .IR thread (2)). .PP -.I Postmountsrv + +.I Postsrv and -.I threadpostmountsrv +.I threadpostsrv are wrappers that create a separate process in which to run .IR srv . They do the following: .IP Initialize +.IB s -> infd +and +.IB s -> outfd +to be one end of a freshly allocated pipe. +.IP +If +.B name +is non-nil, post the other end file descriptor under the name +.BI /srv/ name . +.IP +Initialize .IB s -> forker to eigther .I srvforker @@ -208,24 +219,6 @@ or .I threadsrvforker unless already initialized to a non-nil value. .IP -Initialize -.IB s -> infd -and -.IB s -> outfd -to be one end of a freshly allocated pipe, -with -.IB s -> srvfd -initialized as the other end. -.IP -If -.B name -is non-nil, post the file descriptor -.IB s -> srvfd -under the name -.BI /srv/ name -using a call to -.IR postsrv . -.IP Fork a child process via .IB s -> forker using the @@ -248,27 +241,37 @@ flag. This way, the service loop will share the original file descriptor table with previously created child processes of the caller. .IP -The child process then calls -.IB close( s -> srvfd ) -and then -.IB srv( s ) \fR; -it will exit once -.I srv -returns. +The child process then closes the other end file descriptor +and calls +.IR srv . .IP -If +The parent process returns from the function with the +mountable file descriptor +.IR sfd . +On error, +.I postsrv +and +.I threadpostsrv +return a file descriptor of +.BR -1 +with error string set. +.PP +.I Postmountsrv +and +.I threadpostmntsrv +call +.I postsrv +with +.I name +and then if .I mtpt is non-nil, call -.BI amount( s -> srvfd, +.BI amount( sfd , .IB mtpt , .IB flag , \fB"")\fR; -otherwise, close -.IB s -> srvfd \fR. -.IP -The parent returns to the caller. -.LP +otherwise, close the file descriptor. If any error occurs during this process, the entire process is terminated by calling .I sysfatal diff --git a/sys/src/cmd/aux/wacom.c b/sys/src/cmd/aux/wacom.c index 5b076873c..876d4ab15 100644 --- a/sys/src/cmd/aux/wacom.c +++ b/sys/src/cmd/aux/wacom.c @@ -329,7 +329,6 @@ main() pipe(fd); tabletsrv.infd = tabletsrv.outfd = fd[0]; - tabletsrv.srvfd = fd[1]; tabletsrv.tree = alloctree(getuser(), getuser(), 0555, 0); tfile = createfile(tabletsrv.tree->root, "tablet", getuser(), 0400, 0); if(rfork(RFPROC | RFMEM | RFNOWAIT | RFNOTEG) > 0) exits(nil); @@ -349,4 +348,4 @@ main() sendout(m); msgdecref(m); } -} \ No newline at end of file +} diff --git a/sys/src/lib9p/listen.c b/sys/src/lib9p/listen.c index c7e8dd02c..b093bc287 100644 --- a/sys/src/lib9p/listen.c +++ b/sys/src/lib9p/listen.c @@ -18,7 +18,7 @@ listensrv(Srv *os, char *addr) *s = *os; s->addr = estrdup9p(addr); - s->infd = s->outfd = s->srvfd = -1; + s->infd = s->outfd = -1; s->fpool = nil; s->rpool = nil; s->msize = 0; diff --git a/sys/src/lib9p/mount.c b/sys/src/lib9p/mount.c index 1adc90bed..1ab41825c 100644 --- a/sys/src/lib9p/mount.c +++ b/sys/src/lib9p/mount.c @@ -8,12 +8,15 @@ void postmountsrv(Srv *s, char *name, char *mtpt, int flag) { - postsrv(s, name); + int sfd; + sfd = postsrv(s, name); + if(sfd < 0) + sysfatal("postsrv: %r"); if(mtpt != nil){ - if(amount(s->srvfd, mtpt, flag, "") == -1) + if(amount(sfd, mtpt, flag, "") == -1) sysfatal("mount %s: %r", mtpt); - /* mount closed s->srvfd */ + /* mount closed sfd */ } else - close(s->srvfd); + close(sfd); } diff --git a/sys/src/lib9p/post.c b/sys/src/lib9p/post.c index 18ded63ba..b2134968c 100644 --- a/sys/src/lib9p/post.c +++ b/sys/src/lib9p/post.c @@ -8,43 +8,41 @@ static void postproc(void *v) { Srv *s = v; - rendezvous(0, 0); - close(s->srvfd); + close((int)(uintptr)rendezvous(s, 0)); srv(s); } -void +int postsrv(Srv *s, char *name) { - char buf[80]; - int fd[2]; - int cfd; + int fd[2], cfd; if(pipe(fd) < 0) - sysfatal("pipe: %r"); - s->infd = s->outfd = fd[1]; - s->srvfd = fd[0]; - + return -1; if(name != nil){ + char buf[80]; + snprint(buf, sizeof buf, "/srv/%s", name); - if((cfd = create(buf, OWRITE|ORCLOSE|OCEXEC, 0600)) < 0) - sysfatal("create %s: %r", buf); - if(fprint(cfd, "%d", s->srvfd) < 0) - sysfatal("write %s: %r", buf); + if((cfd = create(buf, OWRITE|ORCLOSE|OCEXEC, 0600)) < 0 + || fprint(cfd, "%d", fd[0]) < 0){ + close(fd[0]); + fd[0] = -1; + goto Out; + } } else cfd = -1; + /* now we are commited */ + s->infd = s->outfd = fd[1]; if(s->forker == nil) s->forker = srvforker; (*s->forker)(postproc, s, RFNAMEG|RFNOTEG); rfork(RFFDG); - rendezvous(0, 0); - - close(s->infd); - if(s->infd != s->outfd) - close(s->outfd); - + rendezvous(s, (void*)(uintptr)fd[0]); +Out: if(cfd >= 0) close(cfd); + close(fd[1]); + return fd[0]; } diff --git a/sys/src/lib9p/share.c b/sys/src/lib9p/share.c index ff73e9c3e..afa01c2f2 100644 --- a/sys/src/lib9p/share.c +++ b/sys/src/lib9p/share.c @@ -8,7 +8,7 @@ void postsharesrv(Srv *s, char *name, char *mtpt, char *desc) { char buf[80]; - int cfd; + int cfd, sfd; if(mtpt != nil && desc != nil){ snprint(buf, sizeof buf, "#σc/%s", mtpt); @@ -21,12 +21,13 @@ postsharesrv(Srv *s, char *name, char *mtpt, char *desc) } else cfd = -1; - postsrv(s, name); - + sfd = postsrv(s, name); + if(sfd < 0) + sysfatal("postsrv: %r"); if(cfd >= 0){ - if(fprint(cfd, "%d\n", s->srvfd) < 0) + if(fprint(cfd, "%d\n", sfd) < 0) sysfatal("write %s: %r", buf); close(cfd); } - close(s->srvfd); + close(sfd); } diff --git a/sys/src/lib9p/threadpostsrv.c b/sys/src/lib9p/threadpostsrv.c index abdb882e8..b627a8653 100644 --- a/sys/src/lib9p/threadpostsrv.c +++ b/sys/src/lib9p/threadpostsrv.c @@ -4,10 +4,10 @@ #include #include <9p.h> -void +int threadpostsrv(Srv *s, char *name) { if(s->forker == nil) s->forker = threadsrvforker; - postsrv(s, name); + return postsrv(s, name); }