[ion] Fix coputation of Record name crc32

ion/include/ion.h

@@ -34,6 +34,9 @@ const char * fccId();
 // CRC32 : non xor-ed, non reversed, direct, polynomial 4C11DB7
 // Only accepts whole 32bit values
 uint32_t crc32(const uint32_t * data, size_t length);
+// crc32 of a string padded with 0 to get a 32bit value
+uint32_t crc32PaddedString(const char * s, int length);
+
 
 // Provides a true random number
 uint32_t random();

ion/src/shared/crc32.cpp

@@ -23,3 +23,26 @@ uint32_t Ion::crc32(const uint32_t * data, size_t length) {
   }
   return crc;
 }
+
+uint32_t Ion::crc32PaddedString(const char * s, int length) {
+  /* s is a char array. Its length in Bytes is not necessarily a multiple of 4.
+   * However, crc32 method awaits input in a form of uint32_t table. To limit
+   * the use of additional memory, we compute 2 crc32:
+   * - one corresponding to s with a byte length truncated to be a multiple of 4
+   * - the other corresponds to the remaining chars in s padded with 0 to be 4
+   *   bytes long
+   * The CRC32 of s is the crc32 of both. */
+
+  // CRC32 of the truncated string
+  uint32_t c[2] = {0, 0};
+  size_t crc32TruncatedInputSize = length*sizeof(char)/sizeof(uint32_t);
+  c[0] = Ion::crc32((const uint32_t *)s, crc32TruncatedInputSize);
+
+  // CRC32 of the tail of the string
+  uint32_t tailName = 0;
+  size_t tailLength = length - crc32TruncatedInputSize*sizeof(uint32_t)/sizeof(char);
+  strlcpy((char *)&tailName, s+crc32TruncatedInputSize*sizeof(uint32_t)/sizeof(char), tailLength);
+  c[1] = Ion::crc32(&tailName, 1);
+
+  return Ion::crc32((const uint32_t *)c, 2);
+}

ion/src/shared/storage.cpp

@@ -37,7 +37,7 @@ Storage::Record::Record(const char * fullName) {
   const char * dotChar = strchr(fullName, k_dotChar);
   assert(dotChar != nullptr);
   assert(*(dotChar+1) != 0); // Assert there is an extension
-  new (this) Record(fullName, dotChar - fullName + 1, dotChar+1, (fullName + strlen(fullName)) - (dotChar+1) +1);
+  new (this) Record(fullName, dotChar - fullName, dotChar+1, (fullName + strlen(fullName)) - (dotChar+1));
 }
 
 Storage::Record::Record(const char * baseName, const char * extension) {
@@ -49,34 +49,15 @@ Storage::Record::Record(const char * baseName, const char * extension) {
   new (this) Record(baseName, strlen(baseName), extension, strlen(extension));
 }
 
-void Crc32PaddedString(const char * s, int length, uint32_t * crcStore) {
-  /* s is a char array. Its length in Bytes is not necessarily a multiple of 4.
-   * However, crc32 method awaits input in a form of uint32_t table. To limit
-   * the use of additional memory, we compute 2 crc32:
-   * - one corresponding to s with a byte length truncated to be a multiple of 4
-   * - the other corresponds to the remaining chars in s padded with 0 to be 4
-   *   bytes long
-   * The CRC32 of s is the crc32 of both. */
-
-  // CRC32 of the truncated string
-  size_t crc32TruncatedInputSize = length*sizeof(char)/sizeof(uint32_t);
-  *crcStore = Ion::crc32((const uint32_t *)s, crc32TruncatedInputSize);
-
-  // CRC32 of the tail of the string
-  uint32_t tailName = 0;
-  strlcpy((char *)&tailName, s+crc32TruncatedInputSize*sizeof(uint32_t), sizeof(uint32_t)/sizeof(char));
-  *(crcStore+1) = Ion::crc32(&tailName, 1);
-}
-
 Storage::Record::Record(const char * basename, int basenameLength, const char * extension, int extensionLength) {
   assert(basename != nullptr);
   assert(extension != nullptr);
 
   // We compute the CRC32 of the CRC32s of the basename and the extension
-  uint32_t crc32Results[4];
-  Crc32PaddedString(basename, basenameLength, &crc32Results[0]);
-  Crc32PaddedString(extension, extensionLength, &crc32Results[2]);
-  m_fullNameCRC32 = Ion::crc32(crc32Results, 4);
+  uint32_t crc32Results[2];
+  crc32Results[0] = Ion::crc32PaddedString(basename, basenameLength);
+  crc32Results[1] = Ion::crc32PaddedString(extension, extensionLength);
+  m_fullNameCRC32 = Ion::crc32(crc32Results, 2);
 }
 
 // STORAGE
@@ -345,8 +326,8 @@ size_t Storage::overrideFullNameAtPosition(char * position, const char * fullNam
 }
 
 size_t Storage::overrideBaseNameWithExtensionAtPosition(char * position, const char * baseName, const char * extension) {
-  size_t result = strlcpy(position, baseName, strlen(baseName));
-  *(position+result) = k_dotChar;
+  size_t result = strlcpy(position, baseName, strlen(baseName)+1); // strlcpy copies the null terminating char
+  *(position+result) = k_dotChar; // Replace the null terminating char with a dot
   result++;
   result += strlcpy(position+result, extension, strlen(extension)+1);
   return result+1;

ion/test/storage.cpp

@@ -10,6 +10,15 @@ Storage::Record::ErrorStatus putRecordInSharedStorage(const char * baseName, con
   return Storage::sharedStorage()->createRecordWithExtension(baseName, extension, data, dataSize);
 }
 
+QUIZ_CASE(ion_storage_records_crc32) {
+  const char * baseNameRecord = "ionTestStorage";
+  const char * extensionRecord = "record1";
+  const char * fullNameRecord = "ionTestStorage.record1";
+  Storage::Record a(baseNameRecord, extensionRecord);
+  Storage::Record b(fullNameRecord);
+  quiz_assert(a==b);
+}
+
 QUIZ_CASE(ion_storage_store_and_destroy_record) {
   size_t initialStorageAvailableStage = Storage::sharedStorage()->availableSize();