diff options
| -rw-r--r-- | log_manager.cpp | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/log_manager.cpp b/log_manager.cpp index d8f233c..3401e82 100644 --- a/log_manager.cpp +++ b/log_manager.cpp @@ -23,7 +23,10 @@ namespace logging void Manager::commit(uint64_t transactionId, std::string errMsg) { constexpr const auto transactionIdVar = "TRANSACTION_ID"; + // Length of 'TRANSACTION_ID' string. constexpr const auto transactionIdVarSize = strlen(transactionIdVar); + // Length of 'TRANSACTION_ID=' string. + constexpr const auto transactionIdVarOffset = transactionIdVarSize + 1; sd_journal *j = nullptr; int rc = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); @@ -65,10 +68,19 @@ void Manager::commit(uint64_t transactionId, std::string errMsg) continue; } - // The metadata field result will be TRANSACTION_ID=1234. Skip the - // TRANSACTION_ID piece and (=) sign to get the id number to compare. - if (strcmp((data + transactionIdVarSize + 1), - transactionIdStr.c_str()) != 0) + // journald does not guarantee that sd_journal_get_data() returns NULL + // terminated strings, so need to specify the size to use to compare, + // use the returned length instead of anything that relies on NULL + // terminators like strlen(). + // The data variable is in the form of 'TRANSACTION_ID=1234'. Remove + // the TRANSACTION_ID characters plus the (=) sign to do the comparison. + // 'data + transactionIdVarOffset' will be in the form of '1234'. + // 'length - transactionIdVarOffset' will be the length of '1234'. + if ((length <= (transactionIdVarOffset)) || + (transactionIdStr.compare(0, + transactionIdStr.size(), + data + transactionIdVarOffset, + length - transactionIdVarOffset) != 0)) { // The value of the TRANSACTION_ID metadata is not the requested // transaction id number. |
