/*- * Copyright (c) 2014-2015 MongoDB, Inc. * Copyright (c) 2008-2014 WiredTiger, Inc. * All rights reserved. * * See the file LICENSE for redistribution information. */ /* * Quiet compiler warnings about unused function parameters and variables, * and unused function return values. */ #define WT_UNUSED(var) (void)(var) /* Basic constants. */ #define WT_MILLION (1000000) #define WT_BILLION (1000000000) #define WT_KILOBYTE (1024) #define WT_MEGABYTE (1048576) #define WT_GIGABYTE (1073741824) #define WT_TERABYTE ((uint64_t)1099511627776) #define WT_PETABYTE ((uint64_t)1125899906842624) #define WT_EXABYTE ((uint64_t)1152921504606846976) /* * Sizes that cannot be larger than 2**32 are stored in uint32_t fields in * common structures to save space. To minimize conversions from size_t to * uint32_t through the code, we use the following macros. */ #define WT_STORE_SIZE(s) ((uint32_t)(s)) #define WT_PTRDIFF(end, begin) \ ((size_t)((uint8_t *)(end) - (uint8_t *)(begin))) #define WT_PTRDIFF32(end, begin) \ WT_STORE_SIZE(WT_PTRDIFF((end), (begin))) #define WT_BLOCK_FITS(p, len, begin, maxlen) \ ((uint8_t *)(p) >= (uint8_t *)(begin) && \ ((uint8_t *)(p) + (len) <= (uint8_t *)(begin) + (maxlen))) #define WT_PTR_IN_RANGE(p, begin, maxlen) \ WT_BLOCK_FITS((p), 1, (begin), (maxlen)) /* * Align an unsigned value of any type to a specified power-of-2, including the * offset result of a pointer subtraction; do the calculation using the largest * unsigned integer type available. */ #define WT_ALIGN(n, v) \ ((((uintmax_t)(n)) + ((v) - 1)) & ~(((uintmax_t)(v)) - 1)) /* Min, max. */ #define WT_MIN(a, b) ((a) < (b) ? (a) : (b)) #define WT_MAX(a, b) ((a) < (b) ? (b) : (a)) /* Elements in an array. */ #define WT_ELEMENTS(a) (sizeof(a) / sizeof(a[0])) /* 10 level skip lists, 1/4 have a link to the next element. */ #define WT_SKIP_MAXDEPTH 10 #define WT_SKIP_PROBABILITY (UINT32_MAX >> 2) /* * __wt_calloc_def, __wt_calloc_one -- * Most calloc calls don't need separate count or sizeof arguments. */ #define __wt_calloc_def(session, number, addr) \ __wt_calloc(session, (size_t)(number), sizeof(**(addr)), addr) #define __wt_calloc_one(session, addr) \ __wt_calloc(session, (size_t)1, sizeof(**(addr)), addr) /* * __wt_realloc_def -- * Common case allocate-and-grow function. * Starts by allocating the requested number of items (at least 10), then * doubles each time the list needs to grow. */ #define __wt_realloc_def(session, sizep, number, addr) \ (((number) * sizeof(**(addr)) <= *(sizep)) ? 0 : \ __wt_realloc(session, sizep, WT_MAX(*(sizep) * 2, \ WT_MAX(10, (number)) * sizeof(**(addr))), addr)) /* * Our internal free function clears the underlying address atomically so there * is a smaller chance of racing threads seeing intermediate results while a * structure is being free'd. (That would be a bug, of course, but I'd rather * not drop core, just the same.) That's a non-standard "free" API, and the * resulting bug is a mother to find -- make sure we get it right, don't make * the caller remember to put the & operator on the pointer. */ #define __wt_free(session, p) do { \ if ((p) != NULL) \ __wt_free_int(session, (void *)&(p)); \ } while (0) #ifdef HAVE_DIAGNOSTIC #define __wt_overwrite_and_free(session, p) do { \ memset(p, WT_DEBUG_BYTE, sizeof(*(p))); \ __wt_free(session, p); \ } while (0) #define __wt_overwrite_and_free_len(session, p, len) do { \ memset(p, WT_DEBUG_BYTE, len); \ __wt_free(session, p); \ } while (0) #else #define __wt_overwrite_and_free(session, p) __wt_free(session, p) #define __wt_overwrite_and_free_len(session, p, len) __wt_free(session, p) #endif /* * Flag set, clear and test. * * They come in 3 flavors: F_XXX (handles a field named "flags" in the structure * referenced by its argument), LF_XXX (handles a local variable named "flags"), * and FLD_XXX (handles any variable, anywhere). * * Flags are unsigned 32-bit values -- we cast to keep the compiler quiet (the * hex constant might be a negative integer), and to ensure the hex constant is * the correct size before applying the bitwise not operator. */ #define FLD_CLR(field, mask) ((field) &= ~((uint32_t)(mask))) #define FLD_MASK(field, mask) ((field) & (uint32_t)(mask)) #define FLD_ISSET(field, mask) (FLD_MASK(field, mask) != 0) #define FLD64_ISSET(field, mask) (((field) & (uint64_t)(mask)) != 0) #define FLD_SET(field, mask) ((field) |= ((uint32_t)(mask))) #define F_CLR(p, mask) FLD_CLR((p)->flags, mask) #define F_ISSET(p, mask) FLD_ISSET((p)->flags, mask) #define F_MASK(p, mask) FLD_MASK((p)->flags, mask) #define F_SET(p, mask) FLD_SET((p)->flags, mask) #define LF_CLR(mask) FLD_CLR(flags, mask) #define LF_ISSET(mask) FLD_ISSET(flags, mask) #define LF_MASK(mask) FLD_MASK(flags, mask) #define LF_SET(mask) FLD_SET(flags, mask) /* Verbose messages. */ #ifdef HAVE_VERBOSE #define WT_VERBOSE_ISSET(session, f) \ (FLD_ISSET(S2C(session)->verbose, f)) #else #define WT_VERBOSE_ISSET(session, f) 0 #endif /* * Clear a structure, two flavors: inline when we want to guarantee there's * no function call or setup/tear-down of a loop, and the default where the * compiler presumably chooses. Gcc 4.3 is supposed to get this right, but * we've seen problems when calling memset to clear structures in performance * critical paths. */ #define WT_CLEAR_INLINE(type, s) do { \ static const type __clear; \ s = __clear; \ } while (0) #define WT_CLEAR(s) \ memset(&(s), 0, sizeof(s)) /* Check if a string matches a prefix. */ #define WT_PREFIX_MATCH(str, pfx) \ (((const char *)str)[0] == ((const char *)pfx)[0] && \ strncmp((str), (pfx), strlen(pfx)) == 0) /* Check if a non-nul-terminated string matches a prefix. */ #define WT_PREFIX_MATCH_LEN(str, len, pfx) \ ((len) >= strlen(pfx) && WT_PREFIX_MATCH(str, pfx)) /* Check if a string matches a prefix, and move past it. */ #define WT_PREFIX_SKIP(str, pfx) \ (WT_PREFIX_MATCH(str, pfx) ? ((str) += strlen(pfx), 1) : 0) /* * Check if a variable string equals a constant string. Inline the common * case for WiredTiger of a single byte string. This is required because not * all compilers optimize this case in strcmp (e.g., clang). */ #define WT_STREQ(s, cs) \ (sizeof(cs) == 2 ? (s)[0] == (cs)[0] && (s)[1] == '\0' : \ strcmp(s, cs) == 0) /* Check if a string matches a byte string of len bytes. */ #define WT_STRING_MATCH(str, bytes, len) \ (((const char *)str)[0] == ((const char *)bytes)[0] && \ strncmp(str, bytes, len) == 0 && (str)[(len)] == '\0') /* * Macro that produces a string literal that isn't wrapped in quotes, to avoid * tripping up spell checkers. */ #define WT_UNCHECKED_STRING(str) #str /* Function return value and scratch buffer declaration and initialization. */ #define WT_DECL_ITEM(i) WT_ITEM *i = NULL #define WT_DECL_RET int ret = 0 /* If a WT_ITEM data field points somewhere in its allocated memory. */ #define WT_DATA_IN_ITEM(i) \ ((i)->mem != NULL && (i)->data >= (i)->mem && \ WT_PTRDIFF((i)->data, (i)->mem) < (i)->memsize) /* Copy the data and size fields of an item. */ #define WT_ITEM_SET(dst, src) do { \ (dst).data = (src).data; \ (dst).size = (src).size; \ } while (0) /* * In diagnostic mode we track the locations from which hazard pointers and * scratch buffers were acquired. */ #ifdef HAVE_DIAGNOSTIC #define __wt_scr_alloc(session, size, scratchp) \ __wt_scr_alloc_func(session, size, scratchp, __FILE__, __LINE__) #define __wt_page_in(session, ref, flags) \ __wt_page_in_func(session, ref, flags, __FILE__, __LINE__) #define __wt_page_swap(session, held, want, flags) \ __wt_page_swap_func(session, held, want, flags, __FILE__, __LINE__) #else #define __wt_scr_alloc(session, size, scratchp) \ __wt_scr_alloc_func(session, size, scratchp) #define __wt_page_in(session, ref, flags) \ __wt_page_in_func(session, ref, flags) #define __wt_page_swap(session, held, want, flags) \ __wt_page_swap_func(session, held, want, flags) #endif /* Random number generator state. */ union __wt_rand_state { uint64_t v; struct { uint32_t w, z; } x; };