Re: [PATCH v6 08/42] refs.c: change ref_transaction_update() to do error checking and return status

Thanks!

On Mon, May 5, 2014 at 6:08 AM, Michael Haggerty [off-list ref] wrote:

On 05/01/2014 10:37 PM, Ronnie Sahlberg wrote:

quoted

Update ref_transaction_update() do some basic error checking and return
true on error. Update all callers to check ref_transaction_update() for error.
There are currently no conditions in _update that will return error but there
will be in the future.

I would change s/true/non-zero/, because error return values are not
just boolean values; the error values sometimes encode the type of error
that occurred.

Done.

quoted

Signed-off-by: Ronnie Sahlberg <redacted>
---
 builtin/update-ref.c | 10 ++++++----
 refs.c               |  9 +++++++--
 refs.h               | 10 +++++-----
 3 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/builtin/update-ref.c b/builtin/update-ref.c
index 2bef2a0..59c4d6b 100644
--- a/builtin/update-ref.c
+++ b/builtin/update-ref.c

@@ -197,8 +197,9 @@ static const char *parse_cmd_update(struct strbuf *input, const char *next)
      if (*next != line_termination)
              die("update %s: extra input: %s", refname, next);

-     ref_transaction_update(transaction, refname, new_sha1, old_sha1,
-                            update_flags, have_old);
+     if (ref_transaction_update(transaction, refname, new_sha1, old_sha1,
+                                update_flags, have_old))
+             die("update %s: failed", refname);

      update_flags = 0;
      free(refname);

@@ -286,8 +287,9 @@ static const char *parse_cmd_verify(struct strbuf *input, const char *next)
      if (*next != line_termination)
              die("verify %s: extra input: %s", refname, next);

-     ref_transaction_update(transaction, refname, new_sha1, old_sha1,
-                            update_flags, have_old);
+     if (ref_transaction_update(transaction, refname, new_sha1, old_sha1,
+                                update_flags, have_old))
+             die("failed transaction update for %s", refname);

      update_flags = 0;
      free(refname);

diff --git a/refs.c b/refs.c
index 308e13e..1a903fb 100644
--- a/refs.c
+++ b/refs.c

@@ -3333,19 +3333,24 @@ static struct ref_update *add_update(struct ref_transaction *transaction,
      return update;
 }

-void ref_transaction_update(struct ref_transaction *transaction,
+int ref_transaction_update(struct ref_transaction *transaction,
                          const char *refname,
                          const unsigned char *new_sha1,
                          const unsigned char *old_sha1,
                          int flags, int have_old)
 {
-     struct ref_update *update = add_update(transaction, refname);
+     struct ref_update *update;
+
+     if (have_old && !old_sha1)
+             die("have_old is true but old_sha1 is NULL");

This new check is orthogonal to the rest of the patch, isn't it?

Yes.

I have updated the commit message to mention that we also check and
die(BUG:...) for this condition.

quoted

+     update = add_update(transaction, refname);
      hashcpy(update->new_sha1, new_sha1);
      update->flags = flags;
      update->have_old = have_old;
      if (have_old)
              hashcpy(update->old_sha1, old_sha1);
+     return 0;
 }

 void ref_transaction_create(struct ref_transaction *transaction,

diff --git a/refs.h b/refs.h
index bc7715e..0364a3e 100644
--- a/refs.h
+++ b/refs.h

@@ -237,11 +237,11 @@ void ref_transaction_rollback(struct ref_transaction *transaction);
  * that the reference should have had before the update, or zeros if
  * it must not have existed beforehand.
  */

Please update the docstring above to explain the return value.

Done.

quoted

-void ref_transaction_update(struct ref_transaction *transaction,
-                         const char *refname,
-                         const unsigned char *new_sha1,
-                         const unsigned char *old_sha1,
-                         int flags, int have_old);
+int ref_transaction_update(struct ref_transaction *transaction,
+                        const char *refname,
+                        const unsigned char *new_sha1,
+                        const unsigned char *old_sha1,
+                        int flags, int have_old);

 /*
  * Add a reference creation to transaction.  new_sha1 is the value

Michael

--
Michael Haggerty
mhagger@alum.mit.edu
http://softwareswirl.blogspot.com/