From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:38037) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gyI5I-0000l6-M2 for qemu-devel@nongnu.org; Mon, 25 Feb 2019 10:22:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gyI5E-0001Nu-Ky for qemu-devel@nongnu.org; Mon, 25 Feb 2019 10:22:24 -0500 From: Kevin Wolf Date: Mon, 25 Feb 2019 16:20:17 +0100 Message-Id: <20190225152053.15976-36-kwolf@redhat.com> In-Reply-To: <20190225152053.15976-1-kwolf@redhat.com> References: <20190225152053.15976-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL 35/71] 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: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org From: Max Reitz 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 Message-id: 20190201192935.18394-10-mreitz@redhat.com Signed-off-by: Max Reitz --- 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 aaae900925..e233372a3a 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -496,9 +496,7 @@ 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 3b33941c5b..91859a928d 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 @@ -4657,8 +4666,8 @@ 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)) { @@ -4667,8 +4676,8 @@ 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 464b718352..32e4e7589a 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 2.20.1