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[PATCH] khash: clarify that allocations never fail

From
René Scharfe <l.s.r@web.de>
Date
Jul 3, 2021, 10:05 UTC
Message-ID
<d13b50fd-5944-0bbe-d28e-8232a2932598@web.de>

We use our standard allocation functions and macros (xcalloc, ALLOC_ARRAY, REALLOC_ARRAY) in our version of khash.h. They terminate the program on error, so code that's using them doesn't have to handle allocation failures. Make this behavior explicit by replacing the code that handles allocation errors in kh_resize_ and kh_put_ with BUG calls.

Signed-off-by: René Scharfe <l.s.r@web.de>
---
 khash.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/khash.h b/khash.h
index 21c2095216..84ff7230b6 100644
--- a/khash.h
+++ b/khash.h
@@ -126,7 +126,7 @@ static const double __ac_HASH_UPPER = 0.77;
 			if (h->size >= (khint_t)(new_n_buckets * __ac_HASH_UPPER + 0.5)) j = 0;	/* requested size is too small */ \
 			else { /* hash table size to be changed (shrink or expand); rehash */ \
 				ALLOC_ARRAY(new_flags, __ac_fsize(new_n_buckets)); \
-				if (!new_flags) return -1;								\
+				if (!new_flags) BUG("ALLOC_ARRAY failed");				\
 				memset(new_flags, 0xaa, __ac_fsize(new_n_buckets) * sizeof(khint32_t)); \
 				if (h->n_buckets < new_n_buckets) {	/* expand */		\
 					REALLOC_ARRAY(h->keys, new_n_buckets); \
@@ -181,10 +181,10 @@ static const double __ac_HASH_UPPER = 0.77;
 		if (h->n_occupied >= h->upper_bound) { /* update the hash table */ \
 			if (h->n_buckets > (h->size<<1)) {							\
 				if (kh_resize_##name(h, h->n_buckets - 1) < 0) { /* clear "deleted" elements */ \
-					*ret = -1; return h->n_buckets;						\
+					BUG("kh_resize_" #name " failed");					\
 				}														\
 			} else if (kh_resize_##name(h, h->n_buckets + 1) < 0) { /* expand the hash table */ \
-				*ret = -1; return h->n_buckets;							\
+				BUG("kh_resize_" #name " failed");						\
 			}															\
 		} /* TODO: to implement automatically shrinking; resize() already support shrinking */ \
 		{																\
--
2.32.0
Next: Jeff King
Message 1 of 12 in “khash: clarify that allocations never fail”
  1. khash: clarify that allocations never failRené Scharfe, Jul 3, 2021
  2. Jeff KingJul 3, 2021
  3. Jeff KingJul 3, 2021
  4. Ævar Arnfjörð BjarmasonJul 3, 2021
  5. René ScharfeJul 3, 2021
  6. Ævar Arnfjörð BjarmasonJul 3, 2021
  7. Jeff KingJul 4, 2021
  8. René ScharfeJul 4, 2021
  9. Jeff KingJul 4, 2021
  10. René ScharfeJul 3, 2021
  11. khash: clarify that allocations never failRené Scharfe, Jul 3, 2021
  12. Jeff KingJul 4, 2021

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