diff options
author | NAKAMURA Usaku <usa@ruby-lang.org> | 2022-03-19 22:41:16 +0900 |
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committer | NAKAMURA Usaku <usa@ruby-lang.org> | 2022-03-19 22:41:16 +0900 |
commit | 7eaec9a6b355a685a3a9503a005b91f4b3cb4f39 (patch) | |
tree | 696cb2af22077cfbe40519b86ed732d949a4ba01 /io.c | |
parent | 5da2a3e31699570ae1a951c8bbc489040051d19e (diff) |
merge revision(s) b555e659c4974acc423083b71b1bd5ec6a926046: [Backport #18388]
Do not use `fcopyfile` if appending to non-empty file [Bug #18388]
`fcopyfile` appends `src` to `to` and then truncates `to` to it's
original size.
---
io.c | 7 +++++++
test/ruby/test_io.rb | 12 ++++++++++++
2 files changed, 19 insertions(+)
Diffstat (limited to 'io.c')
-rw-r--r-- | io.c | 7 |
1 files changed, 7 insertions, 0 deletions
@@ -11022,6 +11022,13 @@ nogvl_fcopyfile(struct copy_stream_struct *stp) return 0; if (lseek(stp->dst_fd, 0, SEEK_CUR) > (off_t)0) /* if dst IO was already written */ return 0; + if (fcntl(stp->dst_fd, F_GETFL) & O_APPEND) { + /* fcopyfile(3) appends src IO to dst IO and then truncates + * dst IO to src IO's original size. */ + off_t end = lseek(stp->dst_fd, 0, SEEK_END); + lseek(stp->dst_fd, 0, SEEK_SET); + if (end > (off_t)0) return 0; + } if (src_offset > (off_t)0) { off_t r; |