diff options
Diffstat (limited to 'contrib/hstore/hstore.h')
| -rw-r--r-- | contrib/hstore/hstore.h | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/contrib/hstore/hstore.h b/contrib/hstore/hstore.h index 8906397ad23..4e55f6e5e28 100644 --- a/contrib/hstore/hstore.h +++ b/contrib/hstore/hstore.h @@ -49,9 +49,12 @@ typedef struct } HStore; /* - * it's not possible to get more than 2^28 items into an hstore, - * so we reserve the top few bits of the size field. See hstore_compat.c - * for one reason why. Some bits are left for future use here. + * It's not possible to get more than 2^28 items into an hstore, so we reserve + * the top few bits of the size field. See hstore_compat.c for one reason + * why. Some bits are left for future use here. MaxAllocSize makes the + * practical count limit slightly more than 2^28 / 3, or INT_MAX / 24, the + * limit for an hstore full of 4-byte keys and null values. Therefore, we + * don't explicitly check the format-imposed limit. */ #define HS_FLAG_NEWVERSION 0x80000000 @@ -59,6 +62,12 @@ typedef struct #define HS_SETCOUNT(hsp_,c_) ((hsp_)->size_ = (c_) | HS_FLAG_NEWVERSION) +/* + * "x" comes from an existing HS_COUNT() (as discussed, <= INT_MAX/24) or a + * Pairs array length (due to MaxAllocSize, <= INT_MAX/40). "lenstr" is no + * more than INT_MAX, that extreme case arising in hstore_from_arrays(). + * Therefore, this calculation is limited to about INT_MAX / 5 + INT_MAX. + */ #define HSHRDSIZE (sizeof(HStore)) #define CALCDATASIZE(x, lenstr) ( (x) * 2 * sizeof(HEntry) + HSHRDSIZE + (lenstr) ) |