[libvirt] [PATCH v4 1/5] virerror: Make it easier to add new error number

[Erik Skultety]

On Thu, Jan 09, 2020 at 01:45:56PM +0100, Michal Privoznik wrote:
> In v5.0.0-rc1~94 we switched from one huge switch() to an array
> for translating error numbers into error messages. However, the
> array is declared to have VIR_ERR_NUMBER_LAST items which makes
> it impossible to spot this place by compile checking when adding
> new error number.
>
> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
> ---
>  scripts/apibuild.py | 6 ++++++
>  src/util/virerror.c | 4 +++-
>  2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/scripts/apibuild.py b/scripts/apibuild.py
> index 2f7314b379..595c004a4c 100755
> --- a/scripts/apibuild.py
> +++ b/scripts/apibuild.py
> @@ -1657,6 +1657,12 @@ class CParser:
>                  token = ("name", "virloginit")
>              return token
>
> +        elif token[0] == "name" and token[1] == "G_STATIC_ASSERT":
> +            # skip whole line
> +            while token is not None and token[0] != "sep" or token[1] != ";":

This will trigger a TypeError exception if token is None because of operator
precedence.

diff --git a/scripts/apibuild.py b/scripts/apibuild.py
index 595c004a4c..00dd510304 100755
--- a/scripts/apibuild.py
+++ b/scripts/apibuild.py
@@ -1659,7 +1659,8 @@ class CParser:

         elif token[0] == "name" and token[1] == "G_STATIC_ASSERT":
             # skip whole line
-            while token is not None and token[0] != "sep" or token[1] != ";":
+            while token is not None and (token[0] != "sep" or
+                                         token[1] != ";"):
                 token = self.token()
             return self.token()


> +                token = self.token()
> +            return self.token()
> +
>          elif token[0] == "name":
>              if self.type == "":
>                  self.type = token[1]
> diff --git a/src/util/virerror.c b/src/util/virerror.c
> index fd2f77329f..aac6ee3597 100644
> --- a/src/util/virerror.c
> +++ b/src/util/virerror.c
> @@ -910,7 +910,7 @@ typedef struct {
>  } virErrorMsgTuple;
>
>
> -const virErrorMsgTuple virErrorMsgStrings[VIR_ERR_NUMBER_LAST] = {
> +static const virErrorMsgTuple virErrorMsgStrings[] = {
>      [VIR_ERR_OK] = { NULL, NULL },
>      [VIR_ERR_INTERNAL_ERROR] = {
>          N_("internal error"),
> @@ -1235,6 +1235,8 @@ const virErrorMsgTuple virErrorMsgStrings[VIR_ERR_NUMBER_LAST] = {
>          N_("network port not found: %s") },
>  };
>
> +G_STATIC_ASSERT(G_N_ELEMENTS(virErrorMsgStrings) == VIR_ERR_NUMBER_LAST);
> +
>

Safe for freeze:
Reviewed-by: Erik Skultety <eskultet at redhat.com>