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[PATCH v3 06/27] update_refs(): fix constness

From
Michael Haggerty <mhagger@alum.mit.edu>
Date
Apr 7, 2014, 13:47 UTC
Message-ID
<1396878498-19887-7-git-send-email-mhagger@alum.mit.edu>
In-Reply-To
<1396878498-19887-1-git-send-email-mhagger@alum.mit.edu>

The old signature of update_refs() required a (const struct ref_update **) for its updates_orig argument. The "const" is presumably there to promise that the function will not modify the contents of the structures.

But this declaration does not permit the function to be called with a (struct ref_update **), which is perfectly legitimate. C's type system is not powerful enough to express what we'd like. So remove the first "const" from the declaration.

On the other hand, the function *can* promise not to modify the pointers within the array that is passed to it without inconveniencing its callers. So add a "const" that has that effect, making the final declaration (struct ref_update * const *).

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 builtin/update-ref.c | 2 +-
 refs.c               | 2 +-
 refs.h               | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/builtin/update-ref.c b/builtin/update-ref.c
index f6345e5..a8a68e8 100644
--- a/builtin/update-ref.c
+++ b/builtin/update-ref.c
@@ -14,7 +14,7 @@ static const char * const git_update_ref_usage[] = {
 
 static int updates_alloc;
 static int updates_count;
-static const struct ref_update **updates;
+static struct ref_update **updates;
 
 static char line_termination = '\n';
 static int update_flags;
diff --git a/refs.c b/refs.c
index 196984e..1305eb1 100644
--- a/refs.c
+++ b/refs.c
@@ -3306,7 +3306,7 @@ static int ref_update_reject_duplicates(struct ref_update **updates, int n,
 	return 0;
 }
 
-int update_refs(const char *action, const struct ref_update **updates_orig,
+int update_refs(const char *action, struct ref_update * const *updates_orig,
 		int n, enum action_on_err onerr)
 {
 	int ret = 0, delnum = 0, i;
diff --git a/refs.h b/refs.h
index a713b34..08e60ac 100644
--- a/refs.h
+++ b/refs.h
@@ -228,7 +228,7 @@ int update_ref(const char *action, const char *refname,
 /**
  * Lock all refs and then perform all modifications.
  */
-int update_refs(const char *action, const struct ref_update **updates,
+int update_refs(const char *action, struct ref_update * const *updates,
 		int n, enum action_on_err onerr);
 
 extern int parse_hide_refs_config(const char *var, const char *value, const char *);

-- 
1.9.1
Previous: Michael HaggertyNext: Michael Haggerty
Message 7 of 34 in “Clean up update-refs --stdin and implement ref_transaction”
  1. 00/27 Clean up update-refs --stdin and implement ref_transactionMichael Haggerty, Apr 7, 2014
  2. 01/27 t1400: fix name and expected result of one testMichael Haggerty, Apr 7, 2014
  3. 02/27 t1400: provide more usual input to the commandMichael Haggerty, Apr 7, 2014
  4. 03/27 parse_arg(): really test that argument is properly terminatedMichael Haggerty, Apr 7, 2014
  5. 04/27 t1400: add some more tests involving quoted argumentsMichael Haggerty, Apr 7, 2014
  6. 05/27 refs.h: rename the action_on_err constantsMichael Haggerty, Apr 7, 2014
  7. 06/27 update_refs(): fix constnessMichael Haggerty, Apr 7, 2014
  8. 07/27 update-ref --stdin: read the whole input at onceMichael Haggerty, Apr 7, 2014
  9. 08/27 parse_cmd_verify(): copy old_sha1 instead of evaluating <oldvalue> twiceMichael Haggerty, Apr 7, 2014
  10. 09/27 update-ref.c: extract a new function, parse_refname()Michael Haggerty, Apr 7, 2014
  11. 10/27 update-ref --stdin: improve error messages for invalid valuesMichael Haggerty, Apr 7, 2014
  12. 11/27 update-ref --stdin: make error messages more consistentMichael Haggerty, Apr 7, 2014
  13. 12/27 update-ref --stdin: simplify error messages for missing oldvaluesMichael Haggerty, Apr 7, 2014
  14. 13/27 t1400: test that stdin -z update treats empty <newvalue> as zerosMichael Haggerty, Apr 7, 2014
  15. 14/27 update-ref.c: extract a new function, parse_next_sha1()Michael Haggerty, Apr 7, 2014
  16. 15/27 update-ref --stdin -z: deprecate interpreting the empty string as zerosMichael Haggerty, Apr 7, 2014
  17. 16/27 t1400: test one mistake at a timeMichael Haggerty, Apr 7, 2014
  18. 17/27 update-ref --stdin: improve the error message for unexpected EOFMichael Haggerty, Apr 7, 2014
  19. 18/27 update-ref --stdin: harmonize error messagesMichael Haggerty, Apr 7, 2014
  20. 19/27 refs: add a concept of a reference transactionMichael Haggerty, Apr 7, 2014
  21. Junio C HamanoApr 7, 2014
  22. Michael HaggertyApr 14, 2014
  23. Junio C HamanoApr 14, 2014
  24. Michael HaggertyApr 15, 2014
  25. Junio C HamanoApr 15, 2014
  26. 20/27 update-ref --stdin: reimplement using reference transactionsMichael Haggerty, Apr 7, 2014
  27. 21/27 refs: remove API function update_refs()Michael Haggerty, Apr 7, 2014
  28. 22/27 struct ref_update: rename field "ref_name" to "refname"Michael Haggerty, Apr 7, 2014
  29. 23/27 struct ref_update: store refname as a FLEX_ARRAYMichael Haggerty, Apr 7, 2014
  30. 24/27 ref_transaction_commit(): simplify code using temporary variablesMichael Haggerty, Apr 7, 2014
  31. 25/27 struct ref_update: add a lock fieldMichael Haggerty, Apr 7, 2014
  32. 26/27 struct ref_update: add a type fieldMichael Haggerty, Apr 7, 2014
  33. 27/27 ref_transaction_commit(): work with transaction->updates in placeMichael Haggerty, Apr 7, 2014
  34. Ronnie SahlbergApr 11, 2014

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