base64: fix Curl_base64_encode and Curl_base64_decode interfaces

Previous interfaces for these libcurl internal functions did not allow to tell
apart a legitimate zero size result from an error condition. These functions
now return a CURLcode indicating function success or otherwise specific error.
Output size is returned using a pointer argument.

All usage of these two functions, and others closely related, has been adapted
to the new interfaces. Relative error and OOM handling adapted or added where
missing. Unit test 1302 also adapted.

1 files changed, 41 insertions, 24 deletions

diff --git a/tests/unit/unit1302.c b/tests/unit/unit1302.c
index 7a61ec062..fc50c8865 100644
--- a/tests/unit/unit1302.c
+++ b/tests/unit/unit1302.c
@@ -45,63 +45,80 @@ UNITTEST_START
 
 char *output;
 unsigned char *decoded;
-size_t rc;
+size_t size = 0;
+unsigned char anychar = 'x';
+CURLcode rc;
 
-rc = Curl_base64_encode(data, "i", 1, &output);
-fail_unless( rc == 4 , "return code should be 4" );
+rc = Curl_base64_encode(data, "i", 1, &output, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 4, "size should be 4");
 verify_memory( output, "aQ==", 4);
 Curl_safefree(output);
 
-rc = Curl_base64_encode(data, "ii", 2, &output);
-fail_unless( rc == 4 , "return code should be 4" );
+rc = Curl_base64_encode(data, "ii", 2, &output, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 4, "size should be 4");
 verify_memory( output, "aWk=", 4);
 Curl_safefree(output);
 
-rc = Curl_base64_encode(data, "iii", 3, &output);
-fail_unless( rc == 4 , "return code should be 4" );
+rc = Curl_base64_encode(data, "iii", 3, &output, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 4, "size should be 4");
 verify_memory( output, "aWlp", 4);
 Curl_safefree(output);
 
-rc = Curl_base64_encode(data, "iiii", 4, &output);
-fail_unless( rc == 8 , "return code should be 8" );
+rc = Curl_base64_encode(data, "iiii", 4, &output, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 8, "size should be 8");
 verify_memory( output, "aWlpaQ==", 8);
 Curl_safefree(output);
 
 /* 0 length makes it do strlen() */
-rc = Curl_base64_encode(data, "iiii", 0, &output);
-fail_unless( rc == 8 , "return code should be 8" );
+rc = Curl_base64_encode(data, "iiii", 0, &output, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 8, "size should be 8");
 verify_memory( output, "aWlpaQ==", 8);
 Curl_safefree(output);
 
-rc = Curl_base64_decode("aWlpaQ==", &decoded);
-fail_unless(rc == 4, "return code should be 4");
+rc = Curl_base64_decode("aWlpaQ==", &decoded, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 4, "size should be 4");
 verify_memory(decoded, "iiii", 4);
 Curl_safefree(decoded);
 
-rc = Curl_base64_decode("aWlp", &decoded);
-fail_unless(rc == 3, "return code should be 3");
+rc = Curl_base64_decode("aWlp", &decoded, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 3, "size should be 3");
 verify_memory(decoded, "iii", 3);
 Curl_safefree(decoded);
 
-rc = Curl_base64_decode("aWk=", &decoded);
-fail_unless(rc == 2, "return code should be 2");
+rc = Curl_base64_decode("aWk=", &decoded, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 2, "size should be 2");
 verify_memory(decoded, "ii", 2);
 Curl_safefree(decoded);
 
-rc = Curl_base64_decode("aQ==", &decoded);
-fail_unless(rc == 1, "return code should be 1");
+rc = Curl_base64_decode("aQ==", &decoded, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 1, "size should be 1");
 verify_memory(decoded, "i", 2);
 Curl_safefree(decoded);
 
 /* this is an illegal input */
-decoded = NULL;
-rc = Curl_base64_decode("aQ", &decoded);
-fail_unless(rc == 0, "return code should be 0");
+size = 1; /* not zero */
+decoded = &anychar; /* not NULL */
+rc = Curl_base64_decode("aQ", &decoded, &size);
+/* return code indiferent, but output shall be as follows */
+fail_unless(size == 0, "size should be 0");
 fail_if(decoded, "returned pointer should be NULL");
 
 /* this is garbage input that libcurl decodes as far as possible */
-rc = Curl_base64_decode("a\x1f==", &decoded);
-fail_unless(rc == 1, "return code should be 1");
+size = 0;
+decoded = NULL;
+rc = Curl_base64_decode("a\x1f==", &decoded, &size);
+fail_unless(rc == CURLE_OK, "return code should be CURLE_OK");
+fail_unless(size == 1, "size should be 1");
+fail_if(!decoded, "returned pointer should not be NULL");
 Curl_safefree(decoded);
 
 UNITTEST_STOP