support/download: protect from custom commands with spaces in args

Some users may provide custom download commands with spaces in their
arguments, like so:
    BR2_HG="hg --config foo.bar='some space-separated value'"

However, the way we currently call those commands does not account
for the extra quotes, and each space-separated part of the command is
interpreted as separate arguments.

Fix that by calling 'eval' on the commands.

Because of the eval, we must further quote our own arguments, to avoid
the eval further splitting them in case there are spaces (even though
we do not support paths with spaces, better be clean from the onset to
avoid breakage in the future).

We change all the wrappers to use a wrapper-function, even those with
a single call, so they all look alike.

Note that we do not single-quote some of the variables, like ${verbose}
because it can be empty and we really do not want to generate an
empty-string argument. That's not a problem, as ${verbose} would not
normally contain space-separated values (it could get set to something
like '-q -v' but in that case we'd still want two arguments, so that's
fine).

Reported-by: Thomas De Schampheleire <patrickdepinguin@gmail.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas De Schampheleire <patrickdepinguin@gmail.com>
Reviewed-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Tested-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

support/download/bzr

@@ -26,4 +26,10 @@ repo="${2}"
 rev="${3}"
 basename="${4}"
 
-${BZR} export ${verbose} --root="${basename}/" --format=tgz "${output}" "${repo}" -r "${rev}"
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_bzr() {
+    eval ${BZR} "${@}"
+}
+
+_bzr export ${verbose} --root="'${basename}/'" --format=tgz "'${output}'" "'${repo}'" -r "'${rev}'"

support/download/cp

@@ -28,4 +28,10 @@ shift $((OPTIND-1))
 output="${1}"
 source="${2}"
 
-${LOCALFILES} ${verbose} "${source}" "${output}"
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_localfiles() {
+    eval ${LOCALFILES} "${@}"
+}
+
+_localfiles ${verbose} "'${source}'" "'${output}'"

support/download/cvs

@@ -26,6 +26,12 @@ rev="${3}"
 rawname="${4}"
 basename="${5}"
 
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_cvs() {
+    eval ${CVS} "${@}"
+}
+
 if [[ ${rev} =~ ^[0-9] ]]; then
     # Date, because a tag or a branch cannot begin with a number
     select="-D"
@@ -35,7 +41,7 @@ else
 fi
 
 export TZ=UTC
-${CVS} ${verbose} -z3 -d":pserver:anonymous@${repo}" \
-       co -d "${basename}" ${select} "${rev}" -P "${rawname}"
+_cvs ${verbose} -z3 -d"':pserver:anonymous@${repo}'" \
+     co -d "'${basename}'" ${select} "'${rev}'" -P "'${rawname}'"
 
 tar czf "${output}" "${basename}"

support/download/git

@@ -25,6 +25,12 @@ repo="${2}"
 cset="${3}"
 basename="${4}"
 
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_git() {
+    eval ${GIT} "${@}"
+}
+
 # Try a shallow clone, since it is faster than a full clone - but that only
 # works if the version is a ref (tag or branch). Before trying to do a shallow
 # clone we check if ${cset} is in the list provided by git ls-remote. If not
@@ -33,9 +39,9 @@ basename="${4}"
 # Messages for the type of clone used are provided to ease debugging in case of
 # problems
 git_done=0
-if [ -n "$(${GIT} ls-remote "${repo}" "${cset}" 2>&1)" ]; then
+if [ -n "$(_git ls-remote "'${repo}'" "'${cset}'" 2>&1)" ]; then
     printf "Doing shallow clone\n"
-    if ${GIT} clone ${verbose} --depth 1 -b "${cset}" --bare "${repo}" "${basename}"; then
+    if _git clone ${verbose} --depth 1 -b "'${cset}'" --bare "'${repo}'" "'${basename}'"; then
         git_done=1
     else
         printf "Shallow clone failed, falling back to doing a full clone\n"
@@ -43,10 +49,10 @@ if [ -n "$(${GIT} ls-remote "${repo}" "${cset}" 2>&1)" ]; then
 fi
 if [ ${git_done} -eq 0 ]; then
     printf "Doing full clone\n"
-    ${GIT} clone ${verbose} --mirror "${repo}" "${basename}"
+    _git clone ${verbose} --mirror "'${repo}'" "'${basename}'"
 fi
 
 GIT_DIR="${basename}" \
-${GIT} archive --prefix="${basename}/" -o "${output}.tmp" --format=tar "${cset}"
+_git archive --prefix="'${basename}/'" -o "'${output}.tmp'" --format=tar "'${cset}'"
 
 gzip <"${output}.tmp" >"${output}"

support/download/hg

@@ -25,8 +25,14 @@ repo="${2}"
 cset="${3}"
 basename="${4}"
 
-${HG} clone ${verbose} --noupdate "${repo}" "${basename}"
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_hg() {
+    eval ${HG} "${@}"
+}
 
-${HG} archive ${verbose} --repository "${basename}" --type tgz \
-              --prefix "${basename}" --rev "${cset}" \
-              "${output}"
+_hg clone ${verbose} --noupdate "'${repo}'" "'${basename}'"
+
+_hg archive ${verbose} --repository "'${basename}'" --type tgz \
+            --prefix "'${basename}'" --rev "'${cset}'" \
+            "'${output}'"

support/download/scp

@@ -23,4 +23,10 @@ shift $((OPTIND-1))
 output="${1}"
 url="${2}"
 
-${SCP} ${verbose} "${url}" "${output}"
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_scp() {
+    eval ${SCP} "${@}"
+}
+
+_scp ${verbose} "'${url}'" "'${output}'"

support/download/svn

@@ -25,6 +25,12 @@ repo="${2}"
 rev="${3}"
 basename="${4}"
 
-${SVN} export ${verbose} "${repo}@${rev}" "${basename}"
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_svn() {
+    eval ${SVN} "${@}"
+}
+
+_svn export ${verbose} "'${repo}@${rev}'" "'${basename}'"
 
 tar czf "${output}" "${basename}"

support/download/wget

@@ -23,4 +23,10 @@ shift $((OPTIND-1))
 output="${1}"
 url="${2}"
 
-${WGET} ${verbose} -O "${output}" "${url}"
+# Caller needs to single-quote its arguments to prevent them from
+# being expanded a second time (in case there are spaces in them)
+_wget() {
+    eval ${WGET} "${@}"
+}
+
+_wget ${verbose} -O "'${output}'" "'${url}'"