| Message ID | 20230901180235.23980-16-mwilck@suse.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | christophe varoqui |
| Headers | show |
| Series | multipath-tools: user-friendly names rework | expand |
On Fri, Sep 01, 2023 at 08:02:28PM +0200, mwilck@suse.com wrote: > From: Martin Wilck <mwilck@suse.com> > > Save code and syscalls by assembling the content in memory first. > write() may return less bytes written than expected. Deal with it. > Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com> > Signed-off-by: Martin Wilck <mwilck@suse.com> > --- > libmultipath/alias.c | 26 +++++++++++++++++--------- > 1 file changed, 17 insertions(+), 9 deletions(-) > > diff --git a/libmultipath/alias.c b/libmultipath/alias.c > index 76d852f..c26f37c 100644 > --- a/libmultipath/alias.c > +++ b/libmultipath/alias.c > @@ -118,22 +118,30 @@ static int add_binding(Bindings *bindings, const char *alias, const char *wwid) > static int write_bindings_file(const Bindings *bindings, int fd) > { > struct binding *bnd; > - STRBUF_ON_STACK(line); > + STRBUF_ON_STACK(content); > int i; > + size_t len; > > - if (write(fd, BINDINGS_FILE_HEADER, sizeof(BINDINGS_FILE_HEADER) - 1) > - != sizeof(BINDINGS_FILE_HEADER) - 1) > + if (__append_strbuf_str(&content, BINDINGS_FILE_HEADER, > + sizeof(BINDINGS_FILE_HEADER) - 1) == -1) > return -1; > > vector_foreach_slot(bindings, bnd, i) { > - int len; > + if (print_strbuf(&content, "%s %s\n", > + bnd->alias, bnd->wwid) < 0) > + return -1; > + } > + len = get_strbuf_len(&content); > + while (len > 0) { > + ssize_t n = write(fd, get_strbuf_str(&content), len); > > - if ((len = print_strbuf(&line, "%s %s\n", > - bnd->alias, bnd->wwid)) < 0) > + if (n < 0) > + return n; > + else if (n == 0) { > + condlog(2, "%s: short write", __func__); > return -1; > - if (write(fd, get_strbuf_str(&line), len) != len) > - return -1; > - truncate_strbuf(&line, 0); > + } > + len -= n; > } > return 0; > } > -- > 2.41.0 -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
diff --git a/libmultipath/alias.c b/libmultipath/alias.c index 76d852f..c26f37c 100644 --- a/libmultipath/alias.c +++ b/libmultipath/alias.c @@ -118,22 +118,30 @@ static int add_binding(Bindings *bindings, const char *alias, const char *wwid) static int write_bindings_file(const Bindings *bindings, int fd) { struct binding *bnd; - STRBUF_ON_STACK(line); + STRBUF_ON_STACK(content); int i; + size_t len; - if (write(fd, BINDINGS_FILE_HEADER, sizeof(BINDINGS_FILE_HEADER) - 1) - != sizeof(BINDINGS_FILE_HEADER) - 1) + if (__append_strbuf_str(&content, BINDINGS_FILE_HEADER, + sizeof(BINDINGS_FILE_HEADER) - 1) == -1) return -1; vector_foreach_slot(bindings, bnd, i) { - int len; + if (print_strbuf(&content, "%s %s\n", + bnd->alias, bnd->wwid) < 0) + return -1; + } + len = get_strbuf_len(&content); + while (len > 0) { + ssize_t n = write(fd, get_strbuf_str(&content), len); - if ((len = print_strbuf(&line, "%s %s\n", - bnd->alias, bnd->wwid)) < 0) + if (n < 0) + return n; + else if (n == 0) { + condlog(2, "%s: short write", __func__); return -1; - if (write(fd, get_strbuf_str(&line), len) != len) - return -1; - truncate_strbuf(&line, 0); + } + len -= n; } return 0; }