From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51561) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aQEtt-00062z-4s for qemu-devel@nongnu.org; Mon, 01 Feb 2016 08:52:18 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aQEtr-0003MV-Sx for qemu-devel@nongnu.org; Mon, 01 Feb 2016 08:52:17 -0500 Received: from mail-wm0-x22c.google.com ([2a00:1450:400c:c09::22c]:34427) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aQEtr-0003M9-IV for qemu-devel@nongnu.org; Mon, 01 Feb 2016 08:52:15 -0500 Received: by mail-wm0-x22c.google.com with SMTP id 128so72018347wmz.1 for ; Mon, 01 Feb 2016 05:52:15 -0800 (PST) From: Eric Auger Date: Mon, 1 Feb 2016 13:51:48 +0000 Message-Id: <1454334712-12360-5-git-send-email-eric.auger@linaro.org> In-Reply-To: <1454334712-12360-1-git-send-email-eric.auger@linaro.org> References: <1454334712-12360-1-git-send-email-eric.auger@linaro.org> Subject: [Qemu-devel] [PATCH v6 4/8] device_tree: qemu_fdt_getprop converted to use the error API List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: eric.auger@st.com, eric.auger@linaro.org, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, alex.williamson@redhat.com, david@gibson.dropbear.id.au Cc: thomas.lendacky@amd.com, thuth@redhat.com, b.reynal@virtualopensystems.com, patches@linaro.org, crosthwaitepeter@gmail.com, suravee.suthikulpanit@amd.com, pbonzini@redhat.com, alex.bennee@linaro.org, christoffer.dall@linaro.org Current qemu_fdt_getprop exits if the property is not found. It is sometimes needed to read an optional property, in which case we do not wish to exit but simply returns a null value. This patch converts qemu_fdt_getprop to accept an Error **, and existing users are converted to pass &error_fatal. This preserves the existing behaviour. Then to use the API with your optional semantic a null parameter can be conveyed. Signed-off-by: Eric Auger Reviewed-by: Peter Crosthwaite --- v4 -> v5: - add Peter's R-b - remove comment about error_fatal v1 -> v2: - add a doc comment in the header file RFC -> v1: - get rid of qemu_fdt_getprop_optional and implement Peter's suggestion that consists in using the error API Signed-off-by: Eric Auger --- device_tree.c | 11 ++++++----- include/sysemu/device_tree.h | 13 ++++++++++++- 2 files changed, 18 insertions(+), 6 deletions(-) diff --git a/device_tree.c b/device_tree.c index a89b838..2c44a3d 100644 --- a/device_tree.c +++ b/device_tree.c @@ -334,18 +334,18 @@ int qemu_fdt_setprop_string(void *fdt, const char *node_path, } const void *qemu_fdt_getprop(void *fdt, const char *node_path, - const char *property, int *lenp) + const char *property, int *lenp, Error **errp) { int len; const void *r; + if (!lenp) { lenp = &len; } r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp); if (!r) { - error_report("%s: Couldn't get %s/%s: %s", __func__, - node_path, property, fdt_strerror(*lenp)); - exit(1); + error_setg(errp, "%s: Couldn't get %s/%s: %s", __func__, + node_path, property, fdt_strerror(*lenp)); } return r; } @@ -354,7 +354,8 @@ uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path, const char *property) { int len; - const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len); + const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len, + &error_fatal); if (len != 4) { error_report("%s: %s/%s not 4 bytes long (not a cell?)", __func__, node_path, property); diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h index 552df21..48bf3b5 100644 --- a/include/sysemu/device_tree.h +++ b/include/sysemu/device_tree.h @@ -54,8 +54,19 @@ int qemu_fdt_setprop_string(void *fdt, const char *node_path, int qemu_fdt_setprop_phandle(void *fdt, const char *node_path, const char *property, const char *target_node_path); +/** + * qemu_fdt_getprop: retrieve the value of a given property + * @fdt: pointer to the device tree blob + * @node_path: node path + * @property: name of the property to find + * @lenp: fdt error if any or length of the property on success + * @errp: handle to an error object + * + * returns a pointer to the property on success and NULL on failure + */ const void *qemu_fdt_getprop(void *fdt, const char *node_path, - const char *property, int *lenp); + const char *property, int *lenp, + Error **errp); uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path, const char *property); uint32_t qemu_fdt_get_phandle(void *fdt, const char *path); -- 1.9.1