#include "stdio_impl.h"
+#include <stdlib.h>
+
+static void dummy(FILE *f) { }
+weak_alias(dummy, __unlist_locked_file);
int fclose(FILE *f)
{
int r;
- int perm;
- FFINALLOCK(f);
-
- if (!(perm = f->flags & F_PERM)) {
- OFLLOCK();
- if (f->prev) f->prev->next = f->next;
- if (f->next) f->next->prev = f->prev;
- if (libc.ofl_head == f) libc.ofl_head = f->next;
- OFLUNLOCK();
- }
-
+ FLOCK(f);
r = fflush(f);
r |= f->close(f);
+ FUNLOCK(f);
+
+ /* Past this point, f is closed and any further explict access
+ * to it is undefined. However, it still exists as an entry in
+ * the open file list and possibly in the thread's locked files
+ * list, if it was closed while explicitly locked. Functions
+ * which process these lists must tolerate dead FILE objects
+ * (which necessarily have inactive buffer pointers) without
+ * producing any side effects. */
+
+ if (f->flags & F_PERM) return r;
+
+ __unlist_locked_file(f);
+
+ FILE **head = __ofl_lock();
+ if (f->prev) f->prev->next = f->next;
+ if (f->next) f->next->prev = f->prev;
+ if (*head == f) *head = f->next;
+ __ofl_unlock();
+
+ free(f->getln_buf);
+ free(f);
- if (f->getln_buf) free(f->getln_buf);
- if (!perm) free(f);
-
return r;
}