support/mph.h

   1 /*
   2  * Common/shared macros and routines.
   3  *
   4  * This file contains macros of the form
   5  *
   6  *   mph_return_if_TYPE_overflow(val);
   7  *
   8  * Which tests `val' for a TYPE underflow/overflow (that is, is `val' within
   9  * the range for TYPE?).  If `val' can't fit in TYPE, errno is set to
  10  * EOVERFLOW, and `return -1' is executed (which is why it's a macro).
  11  *
  12  * Assumptions:
  13  *
  14  * I'm working from GLibc, so that's the basis for my assumptions.  They may
  15  * not be completely portable, in which case I'll need to fix my assumptions.
  16  * :-(
  17  *
  18  * See the typedefs for type size assumptions.  These typedefs *must* be kept
  19  * in sync with the types used in Mono.Posix.dll.
  20  *
  21  * See also:
  22  *   http://developer.apple.com/documentation/Darwin/Reference/ManPages/
  23  */
  24
  25 #ifndef INC_mph_H
  26 #define INC_mph_H
  27
  28 #include <config.h>
  29
  30 #include <limits.h>             /* LONG_MAX, ULONG_MAX */
  31 #include <errno.h>              /* for ERANGE */
  32 #include <glib.h>               /* for g* types, etc. */
  33
  34 #ifdef HAVE_STDINT_H
  35 #include <stdint.h>             /* for SIZE_MAX */
  36 #endif
  37
  38 #if __APPLE__ || __BSD__ || __FreeBSD__
  39 #define MPH_ON_BSD
  40 #endif
  41
  42 #ifdef HAVE_VISIBILITY_HIDDEN
  43 #define MPH_INTERNAL __attribute__((visibility("hidden")))
  44 #else
  45 #define MPH_INTERNAL
  46 #endif
  47
  48 #if defined (PLATFORM_WIN32) && !defined (EOVERFLOW)
  49 #define EOVERFLOW 75
  50 #endif /* def PLATFORM_WIN32 && ndef EOVERFLOW */
  51
  52 #if !defined (PLATFORM_WIN32)
  53
  54 /*
  55  * Solaris doesn't define these BSD values, and if they're not present then
  56  * map.c:Mono_Posix_FromSeekFlags() breaks badly; see:
  57  * http://bugzilla.gnome.org/show_bug.cgi?id=370081
  58  */
  59
  60 #ifndef L_SET
  61 #define L_SET SEEK_SET
  62 #endif /* ndef L_SET */
  63
  64 #ifndef L_INCR
  65 #define L_INCR SEEK_CUR
  66 #endif /* ndef L_INCR */
  67
  68 #ifndef L_XTND
  69 #define L_XTND SEEK_END
  70 #endif /* ndef L_XTND */
  71
  72 /*
  73  * XATTR_AUTO is a synonym for 0 within XattrFlags, but most systems don't
  74  * define it.  map.c doesn't know that, though, so we ensure that it's defined
  75  * so that the value 0 round-trips through MonoPosixHelper.
  76  */
  77
  78 #ifndef XATTR_AUTO
  79 #define XATTR_AUTO 0
  80 #endif /* ndef XATTR_AUTO */
  81
  82 #endif /* ndef PLATFORM_WIN32 */
  83
  84 typedef    gint64 mph_blkcnt_t;
  85 typedef    gint64 mph_blksize_t;
  86 typedef   guint64 mph_dev_t;
  87 typedef   guint64 mph_ino_t;
  88 typedef   guint64 mph_nlink_t;
  89 typedef    gint64 mph_off_t;
  90 typedef   guint64 mph_size_t;
  91 typedef    gint64 mph_ssize_t;
  92 typedef    gint32 mph_pid_t;
  93 typedef   guint32 mph_gid_t;
  94 typedef   guint32 mph_uid_t;
  95 typedef    gint64 mph_time_t;
  96 typedef    gint64 mph_clock_t;
  97 typedef   guint64 mph_fsblkcnt_t;
  98 typedef   guint64 mph_fsfilcnt_t;
  99
 100 /* Some versions of OS X don't define these typedefs, needed by map.c */
 101 #ifndef HAVE_BLKCNT_T
 102 typedef mph_blkcnt_t blkcnt_t;
 103 #endif
 104
 105 #ifndef HAVE_BLKSIZE_T
 106 typedef mph_blksize_t blksize_t;
 107 #endif
 108
 109 #ifndef HAVE_SUSECONDS_T
 110 typedef gint64 suseconds_t;
 111 #endif
 112
 113 #ifdef HAVE_LARGE_FILE_SUPPORT
 114 #define MPH_OFF_T_MAX G_MAXINT64
 115 #define MPH_OFF_T_MIN G_MININT64
 116 #else
 117 #define MPH_OFF_T_MAX G_MAXINT32
 118 #define MPH_OFF_T_MIN G_MININT32
 119 #endif
 120
 121 #ifdef SIZE_MAX
 122 #define MPH_SIZE_T_MAX SIZE_MAX
 123 #elif SIZEOF_SIZE_T == 8
 124 #define MPH_SIZE_T_MAX  G_MAXUINT64
 125 #elif SIZEOF_SIZE_T == 4
 126 #define MPH_SIZE_T_MAX  G_MAXUINT32
 127 #else
 128 #error "sizeof(size_t) is unknown!"
 129 #endif
 130
 131 #define _mph_return_val_if_cb_(val, ret, cb) G_STMT_START{ \
 132         if (cb (val)) { \
 133                 errno = EOVERFLOW; \
 134                 return ret; \
 135         }}G_STMT_END
 136
 137 #define mph_have_long_overflow(var) ((var) > LONG_MAX || (var) < LONG_MIN)
 138
 139 #define mph_return_val_if_long_overflow(var, ret) \
 140         _mph_return_val_if_cb_(var, ret, mph_have_long_overflow)
 141
 142 #define mph_return_if_long_overflow(var) mph_return_val_if_long_overflow(var, -1)
 143
 144 #define mph_have_ulong_overflow(var) ((var) > ULONG_MAX)
 145
 146 #define mph_return_val_if_ulong_overflow(var, ret) \
 147         _mph_return_val_if_cb_(var, ret, mph_have_ulong_overflow)
 148
 149 #define mph_return_if_ulong_overflow(var) mph_return_val_if_ulong_overflow(var, -1)
 150
 151 #define mph_have_size_t_overflow(var) ((var) > MPH_SIZE_T_MAX)
 152
 153 #define mph_return_val_if_size_t_overflow(var, ret) \
 154         _mph_return_val_if_cb_(var, ret, mph_have_size_t_overflow)
 155
 156 #define mph_return_val_if_ssize_t_overflow(var, ret) \
 157         _mph_return_val_if_cb_(var, ret, mph_have_long_overflow)
 158
 159 #define mph_return_if_size_t_overflow(var) mph_return_val_if_size_t_overflow(var, -1)
 160
 161 #define mph_return_if_ssize_t_overflow(var) mph_return_val_if_ssize_t_overflow(var, -1)
 162
 163 #define mph_have_off_t_overflow(var) \
 164         (((var) < MPH_OFF_T_MIN) || ((var) > MPH_OFF_T_MAX))
 165
 166 #define mph_return_val_if_off_t_overflow(var, ret) \
 167         _mph_return_val_if_cb_(var, ret, mph_have_off_t_overflow)
 168
 169 #define mph_return_if_off_t_overflow(var) mph_return_val_if_size_t_overflow(var, -1)
 170
 171 #define mph_return_if_time_t_overflow(var) mph_return_if_long_overflow(var)
 172
 173 /*
 174  * Helper function for functions which use ERANGE (such as getpwnam_r and
 175  * getgrnam_r).  These functions accept buffers which are dynamically
 176  * allocated so that they're only as large as necessary.  However, Linux and
 177  * Mac OS X differ on how to signal an error value.
 178  *
 179  * Linux returns the error value directly, while Mac OS X is more traditional,
 180  * returning -1 and setting errno accordingly.
 181  *
 182  * Unify the checking in one place.
 183  */
 184 static inline int
 185 recheck_range (int ret)
 186 {
 187         if (ret == ERANGE)
 188                 return 1;
 189         if (ret == -1)
 190                 return errno == ERANGE;
 191         return 0;
 192 }
 193
 194 MPH_INTERNAL char*
 195 _mph_copy_structure_strings (
 196         void *to,         const size_t *to_offsets,
 197         const void *from, const size_t *from_offsets,
 198         size_t num_strings);
 199
 200 #endif /* ndef INC_mph_H */
 201
 202 /*
 203  * vim: noexpandtab
 204  */