[PATCH v6 03/18] reftable/blocksource: stop using `xmmap()`
- From
Patrick Steinhardt <ps@pks.im>
- Date
- Feb 18, 2025, 09:20 UTC
- Message-ID
- <20250218-pks-reftable-drop-git-compat-util-v6-3-8c1f39fb4c02@pks.im>
- In-Reply-To
- <20250218-pks-reftable-drop-git-compat-util-v6-0-8c1f39fb4c02@pks.im>
We use `xmmap()` to map reftables into memory. This function has two problems:
- It causes us to die in case the mmap fails.
- It ties us to the Git codebase.
Refactor the code to use mmap(3p) instead with manual error checking. Note that this function may not be the system-provided mmap(3p), but may point to our `git_mmap()` wrapper that emulates the syscall on systems that do not have mmap(3p) available.
Fix `reftable_block_source_from_file()` to properly bubble up the error code in case the map(3p) call fails.
Signed-off-by: Patrick Steinhardt <ps@pks.im> --- reftable/blocksource.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/reftable/blocksource.c b/reftable/blocksource.c index bba4a45b98a..02972c46f4b 100644 --- a/reftable/blocksource.c +++ b/reftable/blocksource.c @@ -98,7 +98,7 @@ static struct reftable_block_source_vtable file_vtable = { int reftable_block_source_from_file(struct reftable_block_source *bs, const char *name) { - struct file_block_source *p; + struct file_block_source *p = NULL; struct stat st; int fd, err; @@ -122,7 +122,12 @@ int reftable_block_source_from_file(struct reftable_block_source *bs, } p->size = st.st_size; - p->data = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + p->data = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + if (p->data == MAP_FAILED) { + err = REFTABLE_IO_ERROR; + p->data = NULL; + goto out; + } assert(!bs->ops); bs->ops = &file_vtable; @@ -135,5 +140,5 @@ int reftable_block_source_from_file(struct reftable_block_source *bs, close(fd); if (err < 0) reftable_free(p); - return 0; + return err; }
-- 2.48.1.666.gff9fcf71b7.dirty