[PATCH v5 04/13] csum-file: add CSUM_KEEP_OPEN flag
From: Derrick Stolee <hidden>
Date: 2018-02-27 02:33:27
Subsystem:
the rest · Maintainer:
Linus Torvalds
This patch is new to the series due to the interactions with the lockfile API and the hashfile API. I need to ensure the hashfile writes the hash value at the end of the file, but keep the file descriptor open so the lock is valid. I welcome any susggestions to this patch or to the way I use it in the commit that follows. -- >8 -- If we want to use a hashfile on the temporary file for a lockfile, then we need hashclose() to fully write the trailing hash but also keep the file descriptor open. Signed-off-by: Derrick Stolee <redacted> --- csum-file.c | 10 +++++++--- csum-file.h | 1 + 2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/csum-file.c b/csum-file.c
index 5eda7fb..302e6ae 100644
--- a/csum-file.c
+++ b/csum-file.c@@ -66,9 +66,13 @@ int hashclose(struct hashfile *f, unsigned char *result, unsigned int flags) flush(f, f->buffer, the_hash_algo->rawsz); if (flags & CSUM_FSYNC) fsync_or_die(f->fd, f->name); - if (close(f->fd)) - die_errno("%s: sha1 file error on close", f->name); - fd = 0; + if (flags & CSUM_KEEP_OPEN) + fd = f->fd; + else { + if (close(f->fd)) + die_errno("%s: sha1 file error on close", f->name); + fd = 0; + } } else fd = f->fd; if (0 <= f->check_fd) {
diff --git a/csum-file.h b/csum-file.h
index 992e5c0..b7c0e48 100644
--- a/csum-file.h
+++ b/csum-file.h@@ -29,6 +29,7 @@ extern int hashfile_truncate(struct hashfile *, struct hashfile_checkpoint *); /* hashclose flags */ #define CSUM_CLOSE 1 #define CSUM_FSYNC 2 +#define CSUM_KEEP_OPEN 4 extern struct hashfile *hashfd(int fd, const char *name); extern struct hashfile *hashfd_check(const char *name);
--
2.7.4