diff --git a/object-file.c b/object-file.c index f84dcd2f2a7b88..aeca61b8ae3aad 100644 --- a/object-file.c +++ b/object-file.c @@ -1970,56 +1970,59 @@ static void write_object_file_prepare_literally(const struct git_hash_algo *algo hash_object_body(algo, &c, buf, len, oid, hdr, hdrlen); } -static int check_collision(const char *filename_a, const char *filename_b) +#define CHECK_COLLISION_DEST_VANISHED -2 + +static int check_collision(const char *source, const char *dest) { - char buf_a[4096], buf_b[4096]; - int fd_a = -1, fd_b = -1; + char buf_source[4096], buf_dest[4096]; + int fd_source = -1, fd_dest = -1; int ret = 0; - fd_a = open(filename_a, O_RDONLY); - if (fd_a < 0) { - if (errno != ENOENT) - ret = error_errno(_("unable to open %s"), filename_a); + fd_source = open(source, O_RDONLY); + if (fd_source < 0) { + ret = error_errno(_("unable to open %s"), source); goto out; } - fd_b = open(filename_b, O_RDONLY); - if (fd_b < 0) { + fd_dest = open(dest, O_RDONLY); + if (fd_dest < 0) { if (errno != ENOENT) - ret = error_errno(_("unable to open %s"), filename_b); + ret = error_errno(_("unable to open %s"), dest); + else + ret = CHECK_COLLISION_DEST_VANISHED; goto out; } while (1) { ssize_t sz_a, sz_b; - sz_a = read_in_full(fd_a, buf_a, sizeof(buf_a)); + sz_a = read_in_full(fd_source, buf_source, sizeof(buf_source)); if (sz_a < 0) { - ret = error_errno(_("unable to read %s"), filename_a); + ret = error_errno(_("unable to read %s"), source); goto out; } - sz_b = read_in_full(fd_b, buf_b, sizeof(buf_b)); + sz_b = read_in_full(fd_dest, buf_dest, sizeof(buf_dest)); if (sz_b < 0) { - ret = error_errno(_("unable to read %s"), filename_b); + ret = error_errno(_("unable to read %s"), dest); goto out; } - if (sz_a != sz_b || memcmp(buf_a, buf_b, sz_a)) { + if (sz_a != sz_b || memcmp(buf_source, buf_dest, sz_a)) { ret = error(_("files '%s' and '%s' differ in contents"), - filename_a, filename_b); + source, dest); goto out; } - if (sz_a < sizeof(buf_a)) + if (sz_a < sizeof(buf_source)) break; } out: - if (fd_a > -1) - close(fd_a); - if (fd_b > -1) - close(fd_b); + if (fd_source > -1) + close(fd_source); + if (fd_dest > -1) + close(fd_dest); return ret; } @@ -2034,8 +2037,11 @@ int finalize_object_file(const char *tmpfile, const char *filename) int finalize_object_file_flags(const char *tmpfile, const char *filename, enum finalize_object_file_flags flags) { - struct stat st; - int ret = 0; + unsigned retries = 0; + int ret; + +retry: + ret = 0; if (object_creation_mode == OBJECT_CREATION_USES_RENAMES) goto try_rename; @@ -2056,6 +2062,8 @@ int finalize_object_file_flags(const char *tmpfile, const char *filename, * left to unlink. */ if (ret && ret != EEXIST) { + struct stat st; + try_rename: if (!stat(filename, &st)) ret = EEXIST; @@ -2071,9 +2079,17 @@ int finalize_object_file_flags(const char *tmpfile, const char *filename, errno = saved_errno; return error_errno(_("unable to write file %s"), filename); } - if (!(flags & FOF_SKIP_COLLISION_CHECK) && - check_collision(tmpfile, filename)) + if (!(flags & FOF_SKIP_COLLISION_CHECK)) { + ret = check_collision(tmpfile, filename); + if (ret == CHECK_COLLISION_DEST_VANISHED) { + if (retries++ > 5) + return error(_("unable to write repeatedly vanishing file %s"), + filename); + goto retry; + } + else if (ret) return -1; + } unlink_or_warn(tmpfile); }