Re: [libvirt] [PATCH v1 23/32] util: netlink: use VIR_AUTOPTR for aggregate types
On Sat, Jul 28, 2018 at 11:31:38PM +0530, Sukrit Bhatnagar wrote:
> By making use of GNU C's cleanup attribute handled by the
> VIR_AUTOPTR macro for declaring aggregate pointer variables,
> majority of the calls to *Free functions can be dropped, which
> in turn leads to getting rid of most of our cleanup sections.
>
> Signed-off-by: Sukrit Bhatnagar
> ---
> src/util/virnetlink.c | 48 +++-
> 1 file changed, 19 insertions(+), 29 deletions(-)
>
> diff --git a/src/util/virnetlink.c b/src/util/virnetlink.c
> index 8d28387..6b00559 100644
> --- a/src/util/virnetlink.c
> +++ b/src/util/virnetlink.c
> @@ -221,30 +221,31 @@ virNetlinkSendRequest(struct nl_msg *nl_msg, uint32_t
> src_pid,
> ssize_t nbytes;
> int fd;
> int n;
> -virNetlinkHandlePtr nlhandle = NULL;
> +VIR_AUTOPTR(virNetlinkHandle) nlhandle = NULL;
> +virNetlinkHandlePtr temp = NULL;
> struct pollfd fds[1];
> struct nlmsghdr *nlmsg = nlmsg_hdr(nl_msg);
>
> if (protocol >= MAX_LINKS) {
> virReportSystemError(EINVAL,
> _("invalid protocol argument: %d"), protocol);
> -goto error;
> +return NULL;
> }
>
> if (!(nlhandle = virNetlinkCreateSocket(protocol)))
> -goto error;
> +return NULL;
>
> fd = nl_socket_get_fd(nlhandle);
> if (fd < 0) {
> virReportSystemError(errno,
> "%s", _("cannot get netlink socket fd"));
> -goto error;
> +return NULL;
> }
>
> if (groups && nl_socket_add_membership(nlhandle, groups) < 0) {
> virReportSystemError(errno,
> "%s", _("cannot add netlink membership"));
> -goto error;
> +return NULL;
> }
>
> nlmsg_set_dst(nl_msg, &nladdr);
> @@ -255,7 +256,7 @@ virNetlinkSendRequest(struct nl_msg *nl_msg, uint32_t
> src_pid,
> if (nbytes < 0) {
> virReportSystemError(errno,
> "%s", _("cannot send to netlink socket"));
> -goto error;
> +return NULL;
> }
>
> memset(fds, 0, sizeof(fds));
> @@ -273,11 +274,9 @@ virNetlinkSendRequest(struct nl_msg *nl_msg, uint32_t
> src_pid,
> _("no valid netlink response was
> received"));
> }
>
> -return nlhandle;
> +VIR_STEAL_PTR(temp, nlhandle);
>
> - error:
> -virNetlinkFree(nlhandle);
> -return NULL;
> +return temp;
> }
Similarly to patch 16, we don't need to force the usage of the attribute
cleanup everywhere.
>
> /**
> @@ -307,7 +306,7 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
> .nl_groups = 0,
> };
> struct pollfd fds[1];
> -virNetlinkHandlePtr nlhandle = NULL;
> +VIR_AUTOPTR(virNetlinkHandle) nlhandle = NULL;
> int len = 0;
>
> memset(fds, 0, sizeof(fds));
> @@ -335,7 +334,6 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
> *respbuflen = 0;
> }
>
> -virNetlinkFree(nlhandle);
> return ret;
> }
>
> @@ -346,10 +344,8 @@ virNetlinkDumpCommand(struct nl_msg *nl_msg,
>unsigned int protocol, unsigned int groups,
>void *opaque)
> {
> -int ret = -1;
> bool end = false;
> int len = 0;
> -struct nlmsghdr *resp = NULL;
> struct nlmsghdr *msg = NULL;
>
> struct sockaddr_nl nladdr = {
> @@ -357,13 +353,14 @@ virNetlinkDumpCommand(struct nl_msg *nl_msg,
> .nl_pid= dst_pid,
> .nl_groups = 0,
> };
> -virNetlinkHandlePtr nlhandle = NULL;
> +VIR_AUTOPTR(virNetlinkHandle) nlhandle = NULL;
>
> if (!(nlhandle = virNetlinkSendRequest(nl_msg, src_pid, nladdr,
> protocol, groups)))
> -goto cleanup;
> +return -1;
>
> while (!end) {
> +VIR_AUTOFREE(struct nlmsghdr *) resp = NULL;
This patch is about VIR_AUTOPTR, therefore ^this should come in a separate
patch.
> len = nl_recv(nlhandle, &nladdr, (unsigned char **)&resp, NULL);
> VIR_WARNINGS_NO_CAST_ALIGN
> for (msg = resp; NLMSG_OK(msg, len); msg = NLMSG_NEXT(msg, len)) {
> @@ -372,20 +369,14 @@ virNetlinkDumpCommand(struct nl_msg *nl_msg,
> end = true;
>
> if (virNetlinkGetErrorCode(msg, len) < 0)
> -goto cleanup;
> +return -1;
>
> if (callback(msg, opaque) < 0)
> -goto cleanup;
> +return -1;
> }
> -VIR_FREE(resp);
> }
>
> -ret = 0;
> -
> - cleanup:
> -VIR_FREE(resp);
> -virNetlinkFree(nlhandle);
> -return ret;
> +return 0;
> }
>
> /**
> @@ -527,7 +518,7 @@ int
> virNetlinkDelLink(const char *ifname, virNetlinkDelLinkFallback fallback)
> {
> int rc = -1;
> -struct nlmsghdr *resp = NULL;
> +VIR_AUTOFREE(struct nlmsghdr *) resp = NULL;
...here too...
> struct nlmsgerr *err;
[libvirt] [PATCH v1 23/32] util: netlink: use VIR_AUTOPTR for aggregate types
By making use of GNU C's cleanup attribute handled by the
VIR_AUTOPTR macro for declaring aggregate pointer variables,
majority of the calls to *Free functions can be dropped, which
in turn leads to getting rid of most of our cleanup sections.
Signed-off-by: Sukrit Bhatnagar
---
src/util/virnetlink.c | 48 +++-
1 file changed, 19 insertions(+), 29 deletions(-)
diff --git a/src/util/virnetlink.c b/src/util/virnetlink.c
index 8d28387..6b00559 100644
--- a/src/util/virnetlink.c
+++ b/src/util/virnetlink.c
@@ -221,30 +221,31 @@ virNetlinkSendRequest(struct nl_msg *nl_msg, uint32_t
src_pid,
ssize_t nbytes;
int fd;
int n;
-virNetlinkHandlePtr nlhandle = NULL;
+VIR_AUTOPTR(virNetlinkHandle) nlhandle = NULL;
+virNetlinkHandlePtr temp = NULL;
struct pollfd fds[1];
struct nlmsghdr *nlmsg = nlmsg_hdr(nl_msg);
if (protocol >= MAX_LINKS) {
virReportSystemError(EINVAL,
_("invalid protocol argument: %d"), protocol);
-goto error;
+return NULL;
}
if (!(nlhandle = virNetlinkCreateSocket(protocol)))
-goto error;
+return NULL;
fd = nl_socket_get_fd(nlhandle);
if (fd < 0) {
virReportSystemError(errno,
"%s", _("cannot get netlink socket fd"));
-goto error;
+return NULL;
}
if (groups && nl_socket_add_membership(nlhandle, groups) < 0) {
virReportSystemError(errno,
"%s", _("cannot add netlink membership"));
-goto error;
+return NULL;
}
nlmsg_set_dst(nl_msg, &nladdr);
@@ -255,7 +256,7 @@ virNetlinkSendRequest(struct nl_msg *nl_msg, uint32_t
src_pid,
if (nbytes < 0) {
virReportSystemError(errno,
"%s", _("cannot send to netlink socket"));
-goto error;
+return NULL;
}
memset(fds, 0, sizeof(fds));
@@ -273,11 +274,9 @@ virNetlinkSendRequest(struct nl_msg *nl_msg, uint32_t
src_pid,
_("no valid netlink response was received"));
}
-return nlhandle;
+VIR_STEAL_PTR(temp, nlhandle);
- error:
-virNetlinkFree(nlhandle);
-return NULL;
+return temp;
}
/**
@@ -307,7 +306,7 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
.nl_groups = 0,
};
struct pollfd fds[1];
-virNetlinkHandlePtr nlhandle = NULL;
+VIR_AUTOPTR(virNetlinkHandle) nlhandle = NULL;
int len = 0;
memset(fds, 0, sizeof(fds));
@@ -335,7 +334,6 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
*respbuflen = 0;
}
-virNetlinkFree(nlhandle);
return ret;
}
@@ -346,10 +344,8 @@ virNetlinkDumpCommand(struct nl_msg *nl_msg,
unsigned int protocol, unsigned int groups,
void *opaque)
{
-int ret = -1;
bool end = false;
int len = 0;
-struct nlmsghdr *resp = NULL;
struct nlmsghdr *msg = NULL;
struct sockaddr_nl nladdr = {
@@ -357,13 +353,14 @@ virNetlinkDumpCommand(struct nl_msg *nl_msg,
.nl_pid= dst_pid,
.nl_groups = 0,
};
-virNetlinkHandlePtr nlhandle = NULL;
+VIR_AUTOPTR(virNetlinkHandle) nlhandle = NULL;
if (!(nlhandle = virNetlinkSendRequest(nl_msg, src_pid, nladdr,
protocol, groups)))
-goto cleanup;
+return -1;
while (!end) {
+VIR_AUTOFREE(struct nlmsghdr *) resp = NULL;
len = nl_recv(nlhandle, &nladdr, (unsigned char **)&resp, NULL);
VIR_WARNINGS_NO_CAST_ALIGN
for (msg = resp; NLMSG_OK(msg, len); msg = NLMSG_NEXT(msg, len)) {
@@ -372,20 +369,14 @@ virNetlinkDumpCommand(struct nl_msg *nl_msg,
end = true;
if (virNetlinkGetErrorCode(msg, len) < 0)
-goto cleanup;
+return -1;
if (callback(msg, opaque) < 0)
-goto cleanup;
+return -1;
}
-VIR_FREE(resp);
}
-ret = 0;
-
- cleanup:
-VIR_FREE(resp);
-virNetlinkFree(nlhandle);
-return ret;
+return 0;
}
/**
@@ -527,7 +518,7 @@ int
virNetlinkDelLink(const char *ifname, virNetlinkDelLinkFallback fallback)
{
int rc = -1;
-struct nlmsghdr *resp = NULL;
+VIR_AUTOFREE(struct nlmsghdr *) resp = NULL;
struct nlmsgerr *err;
struct ifinfomsg ifinfo = { .ifi_family = AF_UNSPEC };
unsigned int recvbuflen;
@@ -582,7 +573,6 @@ virNetlinkDelLink(const char *ifname,
virNetlinkDelLinkFallback fallback)
rc = 0;
cleanup:
nlmsg_free(nl_msg);
-VIR_FREE(resp);
return rc;
malformed_resp:
@@ -771,7 +761,7 @@ virNetlinkEventCallback(int watch,
void *opaque)
{
virNetlinkEventSrvPrivatePtr srv = opaque;
-struct nlmsghdr *msg;
+VIR_AUTOFREE(struct nlmsghdr *) msg = NULL;
struct sockaddr
