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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 13:54:38 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 13:54:38 +0000 |
commit | 8c1ab65c0f548d20b7f177bdb736daaf603340e1 (patch) | |
tree | df55b7e75bf43f2bf500845b105afe3ac3a5157e /libc-top-half/musl/src/stdio/ftrylockfile.c | |
parent | Initial commit. (diff) | |
download | wasi-libc-b0f726bfa464c79fdf040fa7daed6094ddbffb4c.tar.xz wasi-libc-b0f726bfa464c79fdf040fa7daed6094ddbffb4c.zip |
Adding upstream version 0.0~git20221206.8b7148f.upstream/0.0_git20221206.8b7148f
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'libc-top-half/musl/src/stdio/ftrylockfile.c')
-rw-r--r-- | libc-top-half/musl/src/stdio/ftrylockfile.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/stdio/ftrylockfile.c b/libc-top-half/musl/src/stdio/ftrylockfile.c new file mode 100644 index 0000000..5065058 --- /dev/null +++ b/libc-top-half/musl/src/stdio/ftrylockfile.c @@ -0,0 +1,46 @@ +#include "stdio_impl.h" +#include "pthread_impl.h" +#include <limits.h> + +void __do_orphaned_stdio_locks() +{ + FILE *f; + for (f=__pthread_self()->stdio_locks; f; f=f->next_locked) + a_store(&f->lock, 0x40000000); +} + +void __unlist_locked_file(FILE *f) +{ + if (f->lockcount) { + if (f->next_locked) f->next_locked->prev_locked = f->prev_locked; + if (f->prev_locked) f->prev_locked->next_locked = f->next_locked; + else __pthread_self()->stdio_locks = f->next_locked; + } +} + +void __register_locked_file(FILE *f, pthread_t self) +{ + f->lockcount = 1; + f->prev_locked = 0; + f->next_locked = self->stdio_locks; + if (f->next_locked) f->next_locked->prev_locked = f; + self->stdio_locks = f; +} + +int ftrylockfile(FILE *f) +{ + pthread_t self = __pthread_self(); + int tid = self->tid; + int owner = f->lock; + if ((owner & ~MAYBE_WAITERS) == tid) { + if (f->lockcount == LONG_MAX) + return -1; + f->lockcount++; + return 0; + } + if (owner < 0) f->lock = owner = 0; + if (owner || a_cas(&f->lock, 0, tid)) + return -1; + __register_locked_file(f, self); + return 0; +} |