[libvirt] [PATCH] command: handle empty buffer argument correctly
virBufferContentAndReset (intentionally) returns NULL for a buffer
with no content, but it is feasible to invoke a command with an
explicit empty string.
* src/util/command.c (virCommandAddEnvBuffer): Reject empty string.
(virCommandAddArgBuffer): Allow explicit empty argument.
* tests/commandtest.c (test9): Test it.
* tests/commanddata/test9.log: Adjust.
---
As pointed out here:
https://www.redhat.com/archives/libvir-list/2011-November/msg00435.html
src/util/command.c | 13 ++++++++++++-
tests/commanddata/test9.log | 4 +++-
tests/commandtest.c | 13 ++++++++++++-
3 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/src/util/command.c b/src/util/command.c
index c3ce361..f5effdf 100644
--- a/src/util/command.c
+++ b/src/util/command.c
@@ -983,6 +983,10 @@ virCommandAddEnvBuffer(virCommandPtr cmd, virBufferPtr buf)
virBufferFreeAndReset(buf);
return;
}
+ if (!virBufferUse(buf)) {
+ cmd->has_error = EINVAL;
+ return;
+ }
cmd->env[cmd->nenv++] = virBufferContentAndReset(buf);
}
@@ -1092,7 +1096,14 @@ virCommandAddArgBuffer(virCommandPtr cmd, virBufferPtr buf)
return;
}
- cmd->args[cmd->nargs++] = virBufferContentAndReset(buf);
+ cmd->args[cmd->nargs] = virBufferContentAndReset(buf);
+ if (!cmd->args[cmd->nargs])
+ cmd->args[cmd->nargs] = strdup("");
+ if (!cmd->args[cmd->nargs]) {
+ cmd->has_error = ENOMEM;
+ return;
+ }
+ cmd->nargs++;
}
diff --git a/tests/commanddata/test9.log b/tests/commanddata/test9.log
index 2607530..3a93c19 100644
--- a/tests/commanddata/test9.log
+++ b/tests/commanddata/test9.log
@@ -2,8 +2,10 @@ ARG:-version
ARG:-log=bar.log
ARG:arg1
ARG:arg2
-ARG:arg3
+ARG:
ARG:arg4
+ARG:arg5
+ARG:arg6
ENV:DISPLAY=:0.0
ENV:HOME=/home/test
ENV:HOSTNAME=test
diff --git a/tests/commandtest.c b/tests/commandtest.c
index dd6c248..efc48fe 100644
--- a/tests/commandtest.c
+++ b/tests/commandtest.c
@@ -352,11 +352,22 @@ static int test9(const void *unused ATTRIBUTE_UNUSED)
{
virCommandPtr cmd = virCommandNew(abs_builddir "/commandhelper");
const char* const args[] = { "arg1", "arg2", NULL };
+ virBuffer buf = VIR_BUFFER_INITIALIZER;
virCommandAddArg(cmd, "-version");
virCommandAddArgPair(cmd, "-log", "bar.log");
virCommandAddArgSet(cmd, args);
- virCommandAddArgList(cmd, "arg3", "arg4", NULL);
+ virCommandAddArgBuffer(cmd, &buf);
+ virBufferAddLit(&buf, "arg4");
+ virCommandAddArgBuffer(cmd, &buf);
+ virCommandAddArgList(cmd, "arg5", "arg6", NULL);
+
+ if (virBufferUse(&buf)) {
+ printf("Buffer not transferred\n");
+ virBufferFreeAndReset(&buf);
+ virCommandFree(cmd);
+ return -1;
+ }
if (virCommandRun(cmd, NULL) < 0) {
virErrorPtr err = virGetLastError();
--
1.7.4.4