for multithreaded set*id/setrlimit, handle case where callback does not run

in the current version of __synccall, the callback is always run, so
failure to handle this case did not matter. however, the upcoming
overhaul of __synccall will have failure cases, in which case the
callback does not run and errno is already set. the changes being
committed now are in preparation for that.

diff --git a/src/misc/setrlimit.c b/src/misc/setrlimit.c
index 8a1b8cc..7130d71 100644 (file)
--- a/src/misc/setrlimit.c
+++ b/src/misc/setrlimit.c
@@ -32,16 +32,16 @@ struct ctx {
 static void do_setrlimit(void *p)
 {
        struct ctx *c = p;
-       if (c->err) return;
+       if (c->err>0) return;
        c->err = -__setrlimit(c->res, c->rlim);
 }
 
 int setrlimit(int resource, const struct rlimit *rlim)
 {
-       struct ctx c = { .res = resource, .rlim = rlim };
+       struct ctx c = { .res = resource, .rlim = rlim, .err = -1 };
        __synccall(do_setrlimit, &c);
        if (c.err) {
-               errno = c.err;
+               if (c.err>0) errno = c.err;
                return -1;
        }
        return 0;

diff --git a/src/unistd/setxid.c b/src/unistd/setxid.c
index 9e37ddc..0239f8a 100644 (file)
--- a/src/unistd/setxid.c
+++ b/src/unistd/setxid.c
@@ -32,7 +32,7 @@ int __setxid(int nr, int id, int eid, int sid)
        struct ctx c = { .nr = nr, .id = id, .eid = eid, .sid = sid, .err = -1 };
        __synccall(do_setxid, &c);
        if (c.err) {
-               errno = c.err;
+               if (c.err>0) errno = c.err;
                return -1;
        }
        return 0;