add page

include/binary.h

@@ -0,0 +1,103 @@
+#ifndef _BINARY_H_
+#define _BINARY_H_
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#ifdef __linux__
+#  include <endian.h>
+#endif
+#ifdef __FreeBSD__
+#  include <sys/endian.h>
+#endif
+#ifdef __NetBSD__
+#  include <sys/endian.h>
+#endif
+#ifdef __OpenBSD__
+#  include <sys/types.h>
+#  define be16toh(x) betoh16(x)
+#  define be32toh(x) betoh32(x)
+#  define be64toh(x) betoh64(x)
+#endif
+#ifdef __MAC_10_0
+#  define be16toh(x) ntohs(x)
+#  define be32toh(x) ntohl(x)
+#  define be64toh(x) ntohll(x)
+#  define htobe16(x) ntohs(x)
+#  define htobe32(x) htonl(x)
+#  define htobe64(x) htonll(x)
+#endif
+#ifdef _WIN64
+	#ifdef WORDS_BIGENDIAN
+		#  define be16toh(x) (x)
+		#  define be32toh(x) (x)
+		#  define be64toh(x) (x)
+		#  define htobe16(x) (x)
+		#  define htobe32(x) (x)
+		#  define htobe64(x) (x)
+	#else
+		#  define be16toh(x) _byteswap_ushort(x)
+		#  define be32toh(x) _byteswap_ulong(x)
+		#  define be64toh(x) _byteswap_uint64(x)
+		#  define htobe16(x) _byteswap_ushort(x)
+		#  define htobe32(x) _byteswap_ulong(x)
+		#  define htobe64(x) _byteswap_uint64(x)
+	#endif
+#endif
+
+#ifdef _WIN64
+    #ifdef WORDS_BIGENDIAN
+        #define putle16(buf, x) (*(uint16_t*)(buf) = _byteswap_ushort((uint16_t)(x)))
+        #define putle32(buf, x) (*(uint32_t*)(buf) = _byteswap_ulong((uint32_t)(x)))
+        #define putle64(buf, x) (*(uint64_t*)(buf) = _byteswap_uint64((uint64_t)(x)))
+
+        #define readle16(fd, num) ((~read((fd), &(num), 2))?((num)=_byteswap_ushort((uint16_t)(num))):EOF)
+        #define readle32(fd, num) ((~read((fd), &(num), 4))?((num)=_byteswap_ulong((uint32_t)(num))):EOF)
+        #define readle64(fd, num) ((~read((fd), &(num), 8))?((num)=_byteswap_uint64((uint64_t)(num))):EOF)
+
+        #define le16(buf) _byteswap_ushort(*(uint16_t*)(buf))
+        #define le32(buf) _byteswap_ulong(*(uint32_t*)(buf))
+        #define le64(buf) _byteswap_uint64(*(uint64_t*)(buf))
+    #else
+        #define putle16(buf, x) (*(uint16_t*)(buf) = (uint16_t)(x))
+        #define putle32(buf, x) (*(uint32_t*)(buf) = (uint32_t)(x))
+        #define putle64(buf, x) (*(uint64_t*)(buf) = (uint64_t)(x))
+
+        #define readle16(fd, num) read((fd), &(num), 2)
+        #define readle32(fd, num) read((fd), &(num), 4)
+        #define readle64(fd, num) read((fd), &(num), 8)
+
+        #define le16(buf) (*(uint16_t*)(buf))
+        #define le32(buf) (*(uint32_t*)(buf))
+        #define le64(buf) (*(uint64_t*)(buf))
+    #endif
+#else
+    #ifdef WORDS_BIGENDIAN
+        #define putle16(buf, x) (*(uint16_t*)(buf) = __builtin_bswap16((uint16_t)(x)))
+        #define putle32(buf, x) (*(uint32_t*)(buf) = __builtin_bswap32((uint32_t)(x)))
+        #define putle64(buf, x) (*(uint64_t*)(buf) = __builtin_bswap64((uint64_t)(x)))
+
+        #define readle16(fd, num) ((~read((fd), &(num), 2))?((num)=__builtin_bswap16((uint16_t)(num))):EOF)
+        #define readle32(fd, num) ((~read((fd), &(num), 4))?((num)=__builtin_bswap32((uint32_t)(num))):EOF)
+        #define readle64(fd, num) ((~read((fd), &(num), 8))?((num)=__builtin_bswap64((uint64_t)(num))):EOF)
+
+        #define le16(buf) __builtin_bswap16(*(uint16_t*)(buf))
+        #define le32(buf) __builtin_bswap32(*(uint32_t*)(buf))
+        #define le64(buf) __builtin_bswap64(*(uint64_t*)(buf))
+    #else
+        #define putle16(buf, x) (*(uint16_t*)(buf) = (uint16_t)(x))
+        #define putle32(buf, x) (*(uint32_t*)(buf) = (uint32_t)(x))
+        #define putle64(buf, x) (*(uint64_t*)(buf) = (uint64_t)(x))
+
+        #define readle16(fd, num) read((fd), &(num), 2)
+        #define readle32(fd, num) read((fd), &(num), 4)
+        #define readle64(fd, num) read((fd), &(num), 8)
+
+        #define le16(buf) (*(uint16_t*)(buf))
+        #define le32(buf) (*(uint32_t*)(buf))
+        #define le64(buf) (*(uint64_t*)(buf))
+    #endif
+#endif
+
+#endif

include/page.h

@@ -0,0 +1,33 @@
+#ifndef _PAGE_H_
+#define _PAGE_H_
+
+#include <stdio.h>
+
+#ifndef PAGESZ
+    #define PAGESZ 4096
+#endif
+
+// 获取文件中的第一个空闲页，并将其 mmap 到内存
+// 如果现有空闲均无整页，则新分配一页
+// 返回：
+//    EOF 错误
+void* alloc_page(int fd);
+
+// 释放分配的页，将其标记为空闲以备使用
+// 返回：
+//    EOF 错误
+int free_page(int fd, void* page);
+
+// 获取文件中的第一个满足 size 大小的块
+// 返回：
+//    EOF 错误
+void* alloc_block(int fd, size_t size);
+
+// 释放块，并将其标记为空闲以备使用
+// 值得注意的是，只有在本页最后一块
+// 也被释放后，这一页才会被真正释放
+// 返回：
+//    EOF 错误
+int free_block(int fd, void* page);
+
+#endif