sparkey_hash_write returns successfully when given an invalid hash size

[stephenmathieson]

I know this is a bit edge-casey, but when clobbering an existing hash and providing an invalid hash size, sparkey_hash_write incorrectly returns SPARKEY_SUCCESS.

Test case:

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sparkey/sparkey.h>
#include <assert.h>

#define check(rc) ({  \
  if (SPARKEY_SUCCESS != rc) { \
    fprintf(stderr, "error: %s (L#%d)\n", sparkey_errstring(rc), __LINE__); \
    exit(1); \
  } \
});

int
main(void) {
  sparkey_logwriter *writer = NULL;
  check(sparkey_logwriter_create(&writer, "test.spl", SPARKEY_COMPRESSION_NONE, 0));
  check(sparkey_logwriter_put(writer, 5, (uint8_t *) "key1", 7, (uint8_t *) "value1"));
  check(sparkey_logwriter_put(writer, 5, (uint8_t *) "key2", 7, (uint8_t *) "value2"));
  check(sparkey_logwriter_put(writer, 5, (uint8_t *) "key3", 7, (uint8_t *) "value3"));

  // write a hash with size 4
  check(sparkey_hash_write("test.spi", "test.spl", 4));
  // write a hash with invalid size
  check(sparkey_hash_write("test.spi", "test.spl", 3456789));

  assert(0 && "wrote test.spi with an invalid size :(");

  return 0;
}

[spkrka]

Interesting. It's not really an important bug, since sparkey_hash_write exits early if it notices there's no work to be done, even before it needs to look at the hash size.

I will move the hash size verification earlier in the step (unless it turns out the code gets a lot messier as a result), but I won't make any new release/tag for it since it's somewhat of a contrived example that requires intentional misuse of the api and doesn't actually cause any harm :)

[stephenmathieson]

Haha, yes a very contrived example. It came up writing test cases which should result in failure for a binding I'm working on.

No worries regarding a new tag; I can wait for more useful changes :)

[spkrka]

Does this fix the issue for you? 52faa2d

[stephenmathieson]

#20