i386/ucla/src/lab1/inc/types.h

   1 #ifndef JOS_INC_TYPES_H
   2 #define JOS_INC_TYPES_H
   3
   4 #ifndef NULL
   5 #ifdef __cplusplus
   6 #define NULL __null
   7 #else
   8 #define NULL ((void *) 0)
   9 #endif
  10 #endif
  11
  12 #ifndef __cplusplus
  13 // Represents true-or-false values
  14 typedef int bool;
  15 #endif
  16
  17 // Explicitly-sized versions of integer types
  18 typedef __signed char int8_t;
  19 typedef unsigned char uint8_t;
  20 typedef short int16_t;
  21 typedef unsigned short uint16_t;
  22 typedef int int32_t;
  23 typedef unsigned int uint32_t;
  24 typedef long long int64_t;
  25 typedef unsigned long long uint64_t;
  26
  27 // Pointers and addresses are 32 bits long.
  28 // We use pointer types to represent virtual addresses,
  29 // uintptr_t to represent the numerical values of virtual addresses,
  30 // and physaddr_t to represent physical addresses.
  31 typedef int32_t intptr_t;
  32 typedef uint32_t uintptr_t;
  33 typedef uint32_t physaddr_t;
  34
  35 // Page numbers are 32 bits long.
  36 typedef uint32_t ppn_t;
  37
  38 // size_t is used for memory object sizes.
  39 typedef uint32_t size_t;
  40 // ssize_t is a signed version of ssize_t, used in case there might be an
  41 // error return.
  42 typedef int32_t ssize_t;
  43
  44 // off_t is used for file offsets and lengths.
  45 typedef int32_t off_t;
  46
  47 // Efficient min and max operations
  48 #define MIN(_a, _b)                                             \
  49 ({                                                              \
  50         typeof(_a) __a = (_a);                                  \
  51         typeof(_b) __b = (_b);                                  \
  52         __a <= __b ? __a : __b;                                 \
  53 })
  54 #define MAX(_a, _b)                                             \
  55 ({                                                              \
  56         typeof(_a) __a = (_a);                                  \
  57         typeof(_b) __b = (_b);                                  \
  58         __a >= __b ? __a : __b;                                 \
  59 })
  60
  61 // Rounding operations (efficient when n is a power of 2)
  62 // Round down to the nearest multiple of n
  63 #define ROUNDDOWN(a, n)                                         \
  64 ({                                                              \
  65         uint32_t __a = (uint32_t) (a);                          \
  66         (typeof(a)) (__a - __a % (n));                          \
  67 })
  68 // Round up to the nearest multiple of n
  69 #define ROUNDUP(a, n)                                           \
  70 ({                                                              \
  71         uint32_t __n = (uint32_t) (n);                          \
  72         (typeof(a)) (ROUNDDOWN((uint32_t) (a) + __n - 1, __n)); \
  73 })
  74
  75 // Return the offset of 'member' relative to the beginning of a struct type
  76 #define offsetof(type, member)  ((size_t) (&((type*)0)->member))
  77
  78 // Decoration for functions that are accessed from assembly
  79 #ifdef __cplusplus
  80 #define asmlinkage              extern "C"
  81 #else
  82 #define asmlinkage              /* nothing */
  83 #endif
  84
  85 #endif /* !JOS_INC_TYPES_H */