Re: [libvirt] [PATCH 04/17] virsh: Add helper to request string arguments with error reporting
On 2013年01月22日 02:07, Peter Krempa wrote:
This patch adds a helper function with similar semantics to
vshCommandOptString that requests a string argument, but does some error
reporting without the need to do it in the functions themselves.
The error reporting also provides information about the parameter whose
retrieval failed.
---
tools/virsh.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
tools/virsh.h | 4 ++++
2 files changed, 55 insertions(+)
diff --git a/tools/virsh.c b/tools/virsh.c
index 908c6a1..1a3cab0 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -1417,6 +1417,57 @@ vshCommandOptString(const vshCmd *cmd, const char *name, const
char **value)
}
/**
+ * vshCommandOptStringReq: Get a required string argumment
Trivial, but we usually describe what the function does at [1].
+ * @ctl virsh control structure
And have a ":" after @foo.
+ * @cmd command structure
+ * @name option name
+ * @value result (updated to NULL or the actual value)
s/actual value/option argument/,
+ *
[1]. Right here.
+ * Returns option as string. Prints error message if needed
I think you mean option argument here.
+ * Return value:
+ * 0 if option is correct (available or not required)
+ * -1 and error message printed on error
Not to be captious. But how about rewording above like:
Returns 0 on success or the option is not present and not
requirent, *value is set to the option argument if success;
Or -1 on failure, with error message printed.
+ */
+int
+vshCommandOptStringReq(vshControl *ctl,
+ const vshCmd *cmd,
+ const char *name,
+ const char **value)
+{
+ vshCmdOpt *arg;
+ int ret;
+ const char *error = NULL;
+
+ /* clear out the value */
+ *value = NULL;
+
+ ret = vshCommandOpt(cmd, name,&arg);
+ /* option is not required and not present */
+ if (ret == 0)
+ return 0;
+ /* this should not be propagated here, just to be sure */
+ if (ret == -1)
+ error = N_("Mandatory option not present");
+
+ if (ret == -2)
+ error = N_("Programming error: Invalid option name");
+
+ if (!arg->data)
+ error = N_("Programming error: Requested option is a boolean");
+
+ if (!*arg->data&& !(arg->def->flags& VSH_OFLAG_EMPTY_OK))
+ error = N_("Option argument is empty");
+
+ if (error) {
+ vshError(ctl, _("Failed to get option '%s': %s"), name,
_(error));
+ return -1;
+ }
+
+ *value = arg->data;
+ return 0;
+}
+
+/**
* vshCommandOptLongLong:
* @cmd command reference
* @name option name
diff --git a/tools/virsh.h b/tools/virsh.h
index ab7161f..fec9785 100644
--- a/tools/virsh.h
+++ b/tools/virsh.h
@@ -275,6 +275,10 @@ int vshCommandOptUL(const vshCmd *cmd, const char *name,
int vshCommandOptString(const vshCmd *cmd, const char *name,
const char **value)
ATTRIBUTE_NONNULL(3) ATTRIBUTE_RETURN_CHECK;
+int vshCommandOptStringReq(vshControl *ctl, const vshCmd *cmd,
+ const char *name, const char **value)
+ ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3)
+ ATTRIBUTE_NONNULL(4) ATTRIBUTE_RETURN_CHECK;
int vshCommandOptLongLong(const vshCmd *cmd, const char *name,
long long *value)
ATTRIBUTE_NONNULL(3) ATTRIBUTE_RETURN_CHECK;
ACK with the small nits fixed.