From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33416) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gZ1cY-00070j-Dx for qemu-devel@nongnu.org; Mon, 17 Dec 2018 17:44:23 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gZ1cX-00068q-2P for qemu-devel@nongnu.org; Mon, 17 Dec 2018 17:44:18 -0500 From: Max Reitz Date: Mon, 17 Dec 2018 23:43:26 +0100 Message-Id: <20181217224348.14922-10-mreitz@redhat.com> In-Reply-To: <20181217224348.14922-1-mreitz@redhat.com> References: <20181217224348.14922-1-mreitz@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v12 09/31] block: Make path_combine() return the path List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Max Reitz , Kevin Wolf , Alberto Garcia , Eric Blake Besides being safe for arbitrary path lengths, after some follow-up patches all callers will want a freshly allocated buffer anyway. In the meantime, path_combine_deprecated() is added which has the same interface as path_combine() had before this patch. All callers to that function will be converted in follow-up patches. Signed-off-by: Max Reitz Reviewed-by: Alberto Garcia Reviewed-by: Kevin Wolf --- include/block/block.h | 4 +- block.c | 85 ++++++++++++++++++++++++------------------- block/vmdk.c | 3 +- 3 files changed, 49 insertions(+), 43 deletions(-) diff --git a/include/block/block.h b/include/block/block.h index 1e54c8f505..c69b08bef9 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -494,9 +494,7 @@ void bdrv_get_full_backing_filename_from_filename(con= st char *backed, =20 int path_has_protocol(const char *path); int path_is_absolute(const char *path); -void path_combine(char *dest, int dest_size, - const char *base_path, - const char *filename); +char *path_combine(const char *base_path, const char *filename); =20 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t= pos); int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_= t pos); diff --git a/block.c b/block.c index 22f91fb3ee..933a43c989 100644 --- a/block.c +++ b/block.c @@ -152,53 +152,62 @@ int path_is_absolute(const char *path) #endif } =20 -/* if filename is absolute, just copy it to dest. Otherwise, build a +/* if filename is absolute, just return its duplicate. Otherwise, build = a path to it by considering it is relative to base_path. URL are supported. */ -void path_combine(char *dest, int dest_size, - const char *base_path, - const char *filename) +char *path_combine(const char *base_path, const char *filename) { + const char *protocol_stripped =3D NULL; const char *p, *p1; + char *result; int len; =20 - if (dest_size <=3D 0) - return; if (path_is_absolute(filename)) { - pstrcpy(dest, dest_size, filename); - } else { - const char *protocol_stripped =3D NULL; + return g_strdup(filename); + } =20 - if (path_has_protocol(base_path)) { - protocol_stripped =3D strchr(base_path, ':'); - if (protocol_stripped) { - protocol_stripped++; - } + if (path_has_protocol(base_path)) { + protocol_stripped =3D strchr(base_path, ':'); + if (protocol_stripped) { + protocol_stripped++; } - p =3D protocol_stripped ?: base_path; + } + p =3D protocol_stripped ?: base_path; =20 - p1 =3D strrchr(base_path, '/'); + p1 =3D strrchr(base_path, '/'); #ifdef _WIN32 - { - const char *p2; - p2 =3D strrchr(base_path, '\\'); - if (!p1 || p2 > p1) - p1 =3D p2; + { + const char *p2; + p2 =3D strrchr(base_path, '\\'); + if (!p1 || p2 > p1) { + p1 =3D p2; } + } #endif - if (p1) - p1++; - else - p1 =3D base_path; - if (p1 > p) - p =3D p1; - len =3D p - base_path; - if (len > dest_size - 1) - len =3D dest_size - 1; - memcpy(dest, base_path, len); - dest[len] =3D '\0'; - pstrcat(dest, dest_size, filename); + if (p1) { + p1++; + } else { + p1 =3D base_path; + } + if (p1 > p) { + p =3D p1; } + len =3D p - base_path; + + result =3D g_malloc(len + strlen(filename) + 1); + memcpy(result, base_path, len); + strcpy(result + len, filename); + + return result; +} + +static void path_combine_deprecated(char *dest, int dest_size, + const char *base_path, + const char *filename) +{ + char *combined =3D path_combine(base_path, filename); + pstrcpy(dest, dest_size, combined); + g_free(combined); } =20 /* @@ -316,7 +325,7 @@ void bdrv_get_full_backing_filename_from_filename(con= st char *backed, error_setg(errp, "Cannot use relative backing file names for '%s= '", backed); } else { - path_combine(dest, sz, backed, backing); + path_combine_deprecated(dest, sz, backed, backing); } } =20 @@ -4445,8 +4454,8 @@ BlockDriverState *bdrv_find_backing_image(BlockDriv= erState *bs, } else { /* If not an absolute filename path, make it relative to the= current * image's filename path */ - path_combine(filename_tmp, PATH_MAX, curr_bs->filename, - backing_file); + path_combine_deprecated(filename_tmp, PATH_MAX, curr_bs->fil= ename, + backing_file); =20 /* We are going to compare absolute pathnames */ if (!realpath(filename_tmp, filename_full)) { @@ -4455,8 +4464,8 @@ BlockDriverState *bdrv_find_backing_image(BlockDriv= erState *bs, =20 /* We need to make sure the backing filename we are comparin= g against * is relative to the current image filename (or absolute) *= / - path_combine(filename_tmp, PATH_MAX, curr_bs->filename, - curr_bs->backing_file); + path_combine_deprecated(filename_tmp, PATH_MAX, curr_bs->fil= ename, + curr_bs->backing_file); =20 if (!realpath(filename_tmp, backing_file_full)) { continue; diff --git a/block/vmdk.c b/block/vmdk.c index c7484fddb6..3d3273e65b 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -873,8 +873,7 @@ static int vmdk_parse_extents(const char *desc, Block= DriverState *bs, return -EINVAL; } =20 - extent_path =3D g_malloc0(PATH_MAX); - path_combine(extent_path, PATH_MAX, desc_file_path, fname); + extent_path =3D path_combine(desc_file_path, fname); =20 ret =3D snprintf(extent_opt_prefix, 32, "extents.%d", s->num_ext= ents); assert(ret < 32); --=20 2.19.2