objective-c - 未知类型名称 uint32/uint16

Question

在此头文件中，出现错误:未知类型名称 uint32、uint16。我是 Objective-C 的新手，我正在尝试在 Xcode 中导入一个项目。由于上述问题，构建失败。谷歌没有帮助。尝试在 header 搜索路径( xcode unknown type name 、 unknown type name 'uint8_t', MinGW 、 Xcode - how to include c library and header file to cocoa project? )中添加 /stdint/stdint.h 。构建仍然失败。

   /*-------------------------------------------------------------------------
     *
     * block.h
     *    POSTGRES disk block definitions.
     *
     *
     * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
     * Portions Copyright (c) 1994, Regents of the University of California
     *
     * $PostgreSQL: pgsql/src/include/storage/block.h,v 1.26 2010/01/02 16:58:08 momjian Exp $
     *
     *-------------------------------------------------------------------------
     */
    #ifndef BLOCK_H
    #define BLOCK_H

    /*
     * BlockNumber:
     *
     * each data file (heap or index) is divided into postgres disk blocks
     * (which may be thought of as the unit of i/o -- a postgres buffer
     * contains exactly one disk block).  the blocks are numbered
     * sequentially, 0 to 0xFFFFFFFE.
     *
     * InvalidBlockNumber is the same thing as P_NEW in buf.h.
     *
     * the access methods, the buffer manager and the storage manager are
     * more or less the only pieces of code that should be accessing disk
     * blocks directly.
     */
    typedef uint32 BlockNumber;

    #define InvalidBlockNumber      ((BlockNumber) 0xFFFFFFFF)

    #define MaxBlockNumber          ((BlockNumber) 0xFFFFFFFE)

    /*
     * BlockId:
     *
     * this is a storage type for BlockNumber.  in other words, this type
     * is used for on-disk structures (e.g., in HeapTupleData) whereas
     * BlockNumber is the type on which calculations are performed (e.g.,
     * in access method code).
     *
     * there doesn't appear to be any reason to have separate types except
     * for the fact that BlockIds can be SHORTALIGN'd (and therefore any
     * structures that contains them, such as ItemPointerData, can also be
     * SHORTALIGN'd).  this is an important consideration for reducing the
     * space requirements of the line pointer (ItemIdData) array on each
     * page and the header of each heap or index tuple, so it doesn't seem
     * wise to change this without good reason.
     */
    typedef struct BlockIdData
    {
        uint16      bi_hi;
        uint16      bi_lo;
    } BlockIdData;

Answer 1

通常应该使用的类型命名为uint32_t(这些在C99 中定义，头文件stdint.h)。所有其他的都是非标准的，如果可以的话应该避免。现在就您而言，您无法避免使用非标准类型。因此，为了使您的代码能够编译，您需要将非标准名称映射到标准名称，如下所示:

typedef uint32_t uint32;

您需要为 PostgreSQL 中使用的所有类型添加此映射。一种方法是将它们添加到您的预编译头文件 (.pch) 中，或者在包含 PostgreSQL 头文件之前使用您 #include 的这些 typedef 创建一个头文件。