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我正在开发通过 ODBC (unixodbc) 使用 DB2 数据库的软件。问题是使用 valgrind 运行测试套件会产生大量错误。更不用说一个连接和断开连接会生成 4k 错误消息（下面提供的代码）。我的问题是：

  1. 我在连接和断开连接方面做错了吗？
  2. 是否有清理功能可以释放 libdb2 分配的内存？
  3. Valgrind 也有消息抑制功能，是否有维护 libdb2.so 库的抑制文件？

代码：

static void
connect_disconnect(SQLCHAR *dsn)
{
    SQLRETURN ret = -1;

    SQLHENV env = NULL;
    SQLHDBC dbc = NULL;

    SQLCHAR msg[1024];
    SQLSMALLINT msglen = 0;

    /* env handle */
    SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &env);
    SQLSetEnvAttr(env, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0);

    /* connection */
    SQLAllocHandle(SQL_HANDLE_DBC, env, &dbc);

    ret = SQLDriverConnect(dbc, NULL, (SQLCHAR *)dsn,
        SQL_NTS, msg, sizeof(msg), &msglen, SQL_DRIVER_COMPLETE);
    if (!SQL_SUCCEEDED(ret))
    {
        fprintf(stderr, "Failed to connect to database '%s'.\n", dsn);
        extract_error(dbc, SQL_HANDLE_DBC);
    }

    SQLDisconnect(dbc);
    SQLFreeHandle(SQL_HANDLE_DBC, dbc);
    dbc = NULL;

    SQLFreeHandle(SQL_HANDLE_ENV, env);
    env = NULL;

    return;
}

我在用着：

  1. libdb2.so 从 DSClients-linuxx64-odbc_cli-10.1.0.2-FP002 包中获取，适用于 Linux 64 位。
  2. libodbc.so 版本 2.3.1

编辑

最后一条 valgrind 消息（最大泄漏）：

==1318== 425,880 bytes in 1 blocks are possibly lost in loss record 145 of 145
==1318==    at 0x4C2C04B: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==1318==    by 0x68B313D: _ossMemAlloc (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6A3B513: sqlnlscmsg(char const*, SQLNLS_MSG_FILE_HEADER**, char const*, bool*, char*) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6A3AC90: sqlnlsMessage (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6A3A589: sqlnlsMessage (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6C43128: sqloMessage (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6BDCDE0: sqllcGetMessage(char const*, int, char*, char*, unsigned long, bool, char const*) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6BE0F79: sqllcInitComponent(unsigned int) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6BE14E2: sqllcInitData() (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6BD813C: sqllcGetInstalledKeyType (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6C26653: sqloGetInstalledKeyType (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6B42494: sqleuInvokeActivationRoutine(db2UCconHandle*, SQLEU_UDFSP_ARGS*, sqlca*, bool, unsigned int) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6B413A3: sqleuPerformServerActivationCheck(db2UCconHandle*, sqlca*) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x6B3FF72: sqleUCappConnect (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x69E8F9A: CLI_sqlConnect(CLI_CONNECTINFO*, sqlca*, CLI_ERRORHEADERINFO*) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x699997D: SQLConnect2(CLI_CONNECTINFO*, unsigned char*, short, unsigned char*, short, unsigned char*, short, unsigned char*, short, unsigned char) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x69B2640: SQLDriverConnect2(CLI_CONNECTINFO*, void*, unsigned char*, short, unsigned char*, short, short*, unsigned short, unsigned char, unsigned char, CLI_ERRORHEADERINFO*) (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x698BD4E: SQLDriverConnect (in /usr/local/lib/libdb2.so.1)
==1318==    by 0x4E45962: SQLDriverConnect (in /usr/lib/libodbc.so.2.0.0)
==1318==    by 0x400BF2: connect_disconnect (in /.../db2_leak/test)
==1318==    by 0x400A8F: main (in /.../db2_leak/test)

大多数泄漏是静态的（初始化）。每个连接断开都会增加 80 字节到绝对丢失的字节数。

valgrind 输出的更大部分（不能粘贴超过 500k）： http: //pastebin.com/xZfjy21Q

最大的问题是我找不到由我的行为引起的问题。

编辑

双重检查的二进制文件，都是 64 位的。

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0 回答 0