libvirt/src/util/viralloc.h
John Ferlan 4a718d6a0e util: Remove need for STATIC_ANALYSIS check
Seems recent versions of Coverity have (mostly) resolved the issue using
ternary operations in VIR_FREE (and now VIR_DISPOSE*) macros.  So let's
just remove it and if necessary handle one off issues as the arise.
2016-05-19 16:30:04 -04:00

600 lines
26 KiB
C

/*
* viralloc.h: safer memory allocation
*
* Copyright (C) 2010-2014 Red Hat, Inc.
* Copyright (C) 2008 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*
*/
#ifndef __VIR_MEMORY_H_
# define __VIR_MEMORY_H_
# include "internal.h"
/* Return 1 if an array of N objects, each of size S, cannot exist due
to size arithmetic overflow. S must be positive and N must be
nonnegative. This is a macro, not an inline function, so that it
works correctly even when SIZE_MAX < N.
By gnulib convention, SIZE_MAX represents overflow in size
calculations, so the conservative dividend to use here is
SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
However, malloc (SIZE_MAX) fails on all known hosts where
sizeof(ptrdiff_t) <= sizeof(size_t), so do not bother to test for
exactly-SIZE_MAX allocations on such hosts; this avoids a test and
branch when S is known to be 1. */
# ifndef xalloc_oversized
# define xalloc_oversized(n, s) \
((size_t) (sizeof(ptrdiff_t) <= sizeof(size_t) ? -1 : -2) / (s) < (n))
# endif
/* Don't call these directly - use the macros below */
int virAlloc(void *ptrptr, size_t size, bool report, int domcode,
const char *filename, const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1);
int virAllocN(void *ptrptr, size_t size, size_t count, bool report, int domcode,
const char *filename, const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1);
int virReallocN(void *ptrptr, size_t size, size_t count, bool report, int domcode,
const char *filename, const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1);
int virExpandN(void *ptrptr, size_t size, size_t *count, size_t add, bool report,
int domcode, const char *filename, const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3);
int virResizeN(void *ptrptr, size_t size, size_t *alloc, size_t count, size_t desired,
bool report, int domcode, const char *filename,
const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3);
void virShrinkN(void *ptrptr, size_t size, size_t *count, size_t toremove)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3);
int virInsertElementsN(void *ptrptr, size_t size, size_t at, size_t *countptr,
size_t add, void *newelem,
bool clearOriginal, bool inPlace, bool report, int domcode,
const char *filename, const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(4);
int virDeleteElementsN(void *ptrptr, size_t size, size_t at, size_t *countptr,
size_t toremove, bool inPlace)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(4);
int virAllocVar(void *ptrptr, size_t struct_size, size_t element_size, size_t count,
bool report, int domcode, const char *filename,
const char *funcname, size_t linenr)
ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1);
void virFree(void *ptrptr) ATTRIBUTE_NONNULL(1);
void virDispose(void *ptrptr, size_t count, size_t element_size, size_t *countptr)
ATTRIBUTE_NONNULL(1);
/**
* VIR_ALLOC:
* @ptr: pointer to hold address of allocated memory
*
* Allocate sizeof(*ptr) bytes of memory and store
* the address of allocated memory in 'ptr'. Fill the
* newly allocated memory with zeros.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_ALLOC(ptr) virAlloc(&(ptr), sizeof(*(ptr)), true, VIR_FROM_THIS, \
__FILE__, __FUNCTION__, __LINE__)
/**
* VIR_ALLOC_QUIET:
* @ptr: pointer to hold address of allocated memory
*
* Allocate sizeof(*ptr) bytes of memory and store
* the address of allocated memory in 'ptr'. Fill the
* newly allocated memory with zeros.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_ALLOC_QUIET(ptr) virAlloc(&(ptr), sizeof(*(ptr)), false, 0, NULL, NULL, 0)
/**
* VIR_ALLOC_N:
* @ptr: pointer to hold address of allocated memory
* @count: number of elements to allocate
*
* Allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long and store the address of allocated memory in
* 'ptr'. Fill the newly allocated memory with zeros.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_ALLOC_N(ptr, count) virAllocN(&(ptr), sizeof(*(ptr)), (count), true, \
VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
/**
* VIR_ALLOC_N_QUIET:
* @ptr: pointer to hold address of allocated memory
* @count: number of elements to allocate
*
* Allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long and store the address of allocated memory in
* 'ptr'. Fill the newly allocated memory with zeros.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_ALLOC_N_QUIET(ptr, count) virAllocN(&(ptr), sizeof(*(ptr)), (count), \
false, 0, NULL, NULL, 0)
/**
* VIR_REALLOC_N:
* @ptr: pointer to hold address of allocated memory
* @count: number of elements to allocate
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long and store the address of allocated memory in
* 'ptr'. If 'ptr' grew, the added memory is uninitialized.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_REALLOC_N(ptr, count) virReallocN(&(ptr), sizeof(*(ptr)), (count), \
true, VIR_FROM_THIS, __FILE__, \
__FUNCTION__, __LINE__)
/**
* VIR_REALLOC_N_QUIET:
* @ptr: pointer to hold address of allocated memory
* @count: number of elements to allocate
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long and store the address of allocated memory in
* 'ptr'. If 'ptr' grew, the added memory is uninitialized.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_REALLOC_N_QUIET(ptr, count) virReallocN(&(ptr), sizeof(*(ptr)), (count), \
false, 0, NULL, NULL, 0)
/**
* VIR_EXPAND_N:
* @ptr: pointer to hold address of allocated memory
* @count: variable tracking number of elements currently allocated
* @add: number of elements to add
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long, to be 'count' + 'add' elements long, then store the
* address of allocated memory in 'ptr' and the new size in 'count'.
* The new elements are filled with zero.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_EXPAND_N(ptr, count, add) \
virExpandN(&(ptr), sizeof(*(ptr)), &(count), add, true, VIR_FROM_THIS, \
__FILE__, __FUNCTION__, __LINE__)
/**
* VIR_EXPAND_N_QUIET:
* @ptr: pointer to hold address of allocated memory
* @count: variable tracking number of elements currently allocated
* @add: number of elements to add
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long, to be 'count' + 'add' elements long, then store the
* address of allocated memory in 'ptr' and the new size in 'count'.
* The new elements are filled with zero.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_EXPAND_N_QUIET(ptr, count, add) \
virExpandN(&(ptr), sizeof(*(ptr)), &(count), add, false, 0, NULL, NULL, 0)
/**
* VIR_RESIZE_N:
* @ptr: pointer to hold address of allocated memory
* @alloc: variable tracking number of elements currently allocated
* @count: number of elements currently in use
* @add: minimum number of elements to additionally support
*
* Blindly using VIR_EXPAND_N(array, alloc, 1) in a loop scales
* quadratically, because every iteration must copy contents from
* all prior iterations. But amortized linear scaling can be achieved
* by tracking allocation size separately from the number of used
* elements, and growing geometrically only as needed.
*
* If 'count' + 'add' is larger than 'alloc', then geometrically reallocate
* the array of 'alloc' elements, each sizeof(*ptr) bytes long, and store
* the address of allocated memory in 'ptr' and the new size in 'alloc'.
* The new elements are filled with zero.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_RESIZE_N(ptr, alloc, count, add) \
virResizeN(&(ptr), sizeof(*(ptr)), &(alloc), count, add, true, \
VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
/**
* VIR_RESIZE_N_QUIET:
* @ptr: pointer to hold address of allocated memory
* @alloc: variable tracking number of elements currently allocated
* @count: number of elements currently in use
* @add: minimum number of elements to additionally support
*
* Blindly using VIR_EXPAND_N(array, alloc, 1) in a loop scales
* quadratically, because every iteration must copy contents from
* all prior iterations. But amortized linear scaling can be achieved
* by tracking allocation size separately from the number of used
* elements, and growing geometrically only as needed.
*
* If 'count' + 'add' is larger than 'alloc', then geometrically reallocate
* the array of 'alloc' elements, each sizeof(*ptr) bytes long, and store
* the address of allocated memory in 'ptr' and the new size in 'alloc'.
* The new elements are filled with zero.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_RESIZE_N_QUIET(ptr, alloc, count, add) \
virResizeN(&(ptr), sizeof(*(ptr)), &(alloc), count, add, \
false, 0, NULL, NULL, 0)
/**
* VIR_SHRINK_N:
* @ptr: pointer to hold address of allocated memory
* @count: variable tracking number of elements currently allocated
* @remove: number of elements to remove
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long, to be 'count' - 'remove' elements long, then store the
* address of allocated memory in 'ptr' and the new size in 'count'.
* If 'count' <= 'remove', the entire array is freed.
*
* This macro is safe to use on arguments with side effects.
*
* No return value.
*/
# define VIR_SHRINK_N(ptr, count, remove) \
virShrinkN(&(ptr), sizeof(*(ptr)), &(count), remove)
/**
* VIR_TYPEMATCH:
*
* The following macro seems a bit cryptic, so it needs a thorough
* explanation. Its purpose is to check for assignment compatibility
* and identical size between two values without creating any side
* effects (by doing something silly like actually assigning one to
* the other). Note that it takes advantage of the C89-guaranteed
* property of sizeof() - it cannot have any side effects, so anything
* that happens inside sizeof() will not have any effect at runtime.
*
* VIR_TYPEMATCH evaluates to "1" if the two passed values are both
* assignment-compatible and the same size, and otherwise generates a
* compile-time error. It determines the result by performing the
* following three operations:
*
* * sizeof(*(a) = *(b)) assures that *a and *b are
* assignment-compatible (they may still have a different size
* though! e.g. longVar = intVar) (If not, there is a compile-time
* error. If so, the result of that subexpression is sizeof(*(a)),
* i.e. one element of the array)
*
* * sizeof(*(a) = *(b)) == sizeof(*(b)) checks if *a and *b are also
* of the same size (so that, e.g. you don't accidentally copy an
* int plus the random bytes following it into an array of long). It
* evaluates to 1 if they are the same, and 0 otherwise.
*
* * sizeof(char[2 * (result of previous step) - 1]) evaluates to 1
* if the previous step was successful (char [(2*1) - 1] i.e.
* char[1]), or generates a compile error if it wasn't successful
* (char[2*0 -1] i.e. char[-1], which isn't valid in C).
*
* So VIR_TYPEMATCH(a, b) will either abort the compile with an error,
* or evaluate to "1", and in the meantime check that we've actually
* added the correct &'s and/or *'s to the arguments. (Whew!)
*/
# define VIR_TYPEMATCH(a, b) \
sizeof(char[2 * (sizeof(*(a) = *(b)) == sizeof(*(b))) - 1])
/**
* VIR_INSERT_ELEMENT:
* @ptr: pointer to array of objects (*not* ptr to ptr)
* @at: index within array where new elements should be added
* @count: variable tracking number of elements currently allocated
* @newelem: the new element to move into place (*not* a pointer to
* the element, but the element itself).
* (the original will be zeroed out if successful)
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr) bytes
* long, to be 'count' + 1 elements long, then appropriately move
* the elements starting at ptr[at] up by 1 element, copy the
* item 'newelem' into ptr[at], then store the address of
* allocated memory in 'ptr' and the new size in 'count'.
*
* VIR_INSERT_ELEMENT_COPY is identical, but doesn't clear out the
* original element to 0 on success, so there are two copies of the
* element. This is useful if the "element" is actually just a
* pointer to the real data, and you want to maintain a reference to
* it for use after the insert is completed; but if the "element" is
* an object that points to other allocated memory, having multiple
* copies can cause problems (e.g. double free).
*
* VIR_INSERT_ELEMENT_*INPLACE are identical, but assume any necessary
* memory re-allocation has already been done.
*
* VIR_INSERT_ELEMENT_* all need to send "1" as the "add" argument to
* virInsertElementsN (which has the currently-unused capability of
* inserting multiple items at once). We use this to our advantage by
* replacing it with VIR_TYPECHECK(ptr, &newelem) so that we can be
* assured ptr and &newelem are of compatible types.
*
* These macros are safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_INSERT_ELEMENT(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), true, false, \
true, VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
# define VIR_INSERT_ELEMENT_COPY(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), false, false, \
true, VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
# define VIR_INSERT_ELEMENT_INPLACE(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), true, true, \
true, VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
# define VIR_INSERT_ELEMENT_COPY_INPLACE(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), false, true, \
true, VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
/* Quiet version of macros above */
# define VIR_INSERT_ELEMENT_QUIET(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), true, false, \
false, 0, NULL, NULL, 0)
# define VIR_INSERT_ELEMENT_COPY_QUIET(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), false, false, \
false, 0, NULL, NULL, 0)
# define VIR_INSERT_ELEMENT_INPLACE_QUIET(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), true, true, \
false, 0, NULL, NULL, 0)
# define VIR_INSERT_ELEMENT_COPY_INPLACE_QUIET(ptr, at, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), at, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), false, true, \
false, 0, NULL, NULL, 0)
/**
* VIR_APPEND_ELEMENT:
* @ptr: pointer to array of objects (*not* ptr to ptr)
* @count: variable tracking number of elements currently allocated
* @newelem: the new element to move into place (*not* a pointer to
* the element, but the element itself).
* (the original will be zeroed out if successful)
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr) bytes
* long, to be 'count' + 1 elements long, then copy the item from
* 'newelem' into ptr[count+1], and store the address of allocated
* memory in 'ptr' and the new size in 'count'. If 'newelem' is NULL,
* the new element at ptr[at] is instead filled with zero.
*
* VIR_APPEND_ELEMENT_COPY is identical, but doesn't clear out the
* original element to 0 on success, so there are two copies of the
* element. This is useful if the "element" is actually just a
* pointer to the real data, and you want to maintain a reference to
* it for use after the append is completed; but if the "element" is
* an object that points to other allocated memory, having multiple
* copies can cause problems (e.g. double free).
*
* VIR_APPEND_ELEMENT_*INPLACE are identical, but assume any
* necessary memory re-allocation has already been done.
*
* VIR_APPEND_ELEMENT_* all need to send "1" as the "add" argument to
* virInsertElementsN (which has the currently-unused capability of
* inserting multiple items at once). We use this to our advantage by
* replacing it with VIR_TYPECHECK(ptr, &newelem) so that we can be
* assured ptr and &newelem are of compatible types.
*
* These macros are safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_APPEND_ELEMENT(ptr, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), -1, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), true, false, \
true, VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
# define VIR_APPEND_ELEMENT_COPY(ptr, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), -1, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), false, false, \
true, VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
# define VIR_APPEND_ELEMENT_INPLACE(ptr, count, newelem) \
ignore_value(virInsertElementsN(&(ptr), sizeof(*(ptr)), -1, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), \
&(newelem), true, true, false, \
VIR_FROM_THIS, __FILE__, \
__FUNCTION__, __LINE__))
# define VIR_APPEND_ELEMENT_COPY_INPLACE(ptr, count, newelem) \
ignore_value(virInsertElementsN(&(ptr), sizeof(*(ptr)), -1, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), \
&(newelem), false, true, false, \
VIR_FROM_THIS, __FILE__, \
__FUNCTION__, __LINE__))
/* Quiet version of macros above */
# define VIR_APPEND_ELEMENT_QUIET(ptr, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), -1, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), true, false, \
false, 0, NULL, NULL, 0)
# define VIR_APPEND_ELEMENT_COPY_QUIET(ptr, count, newelem) \
virInsertElementsN(&(ptr), sizeof(*(ptr)), -1, &(count), \
VIR_TYPEMATCH(ptr, &(newelem)), &(newelem), false, false, \
false, 0, NULL, NULL, 0)
/**
* VIR_DELETE_ELEMENT:
* @ptr: pointer to array of objects (*not* ptr to ptr)
* @at: index within array where new elements should be deleted
* @count: variable tracking number of elements currently allocated
*
* Re-allocate an array of 'count' elements, each sizeof(*ptr)
* bytes long, to be 'count' - 1 elements long, then store the
* address of allocated memory in 'ptr' and the new size in 'count'.
* If 'count' <= 1, the entire array is freed.
*
* VIR_DELETE_ELEMENT_INPLACE is identical, but assumes any
* necessary memory re-allocation will be done later.
*
* These macros are safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_DELETE_ELEMENT(ptr, at, count) \
virDeleteElementsN(&(ptr), sizeof(*(ptr)), at, &(count), 1, false)
# define VIR_DELETE_ELEMENT_INPLACE(ptr, at, count) \
virDeleteElementsN(&(ptr), sizeof(*(ptr)), at, &(count), 1, true)
/**
* VIR_ALLOC_VAR_OVERSIZED:
* @M: size of base structure
* @N: number of array elements in trailing array
* @S: size of trailing array elements
*
* Check to make sure that the requested allocation will not cause
* arithmetic overflow in the allocation size. The check is
* essentially the same as that in gnulib's xalloc_oversized.
*/
# define VIR_ALLOC_VAR_OVERSIZED(M, N, S) ((((size_t)-1) - (M)) / (S) < (N))
/**
* VIR_ALLOC_VAR:
* @ptr: pointer to hold address of allocated memory
* @type: element type of trailing array
* @count: number of array elements to allocate
*
* Allocate sizeof(*ptr) bytes plus an array of 'count' elements, each
* sizeof('type'). This sort of allocation is useful for receiving
* the data of certain ioctls and other APIs which return a struct in
* which the last element is an array of undefined length. The caller
* of this type of API is expected to know the length of the array
* that will be returned and allocate a suitable buffer to contain the
* returned data. C99 refers to these variable length objects as
* structs containing flexible array members.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure (with OOM error reported), 0 on success
*/
# define VIR_ALLOC_VAR(ptr, type, count) \
virAllocVar(&(ptr), sizeof(*(ptr)), sizeof(type), (count), true, \
VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
/**
* VIR_ALLOC_VAR_QUIET:
* @ptr: pointer to hold address of allocated memory
* @type: element type of trailing array
* @count: number of array elements to allocate
*
* Allocate sizeof(*ptr) bytes plus an array of 'count' elements, each
* sizeof('type'). This sort of allocation is useful for receiving
* the data of certain ioctls and other APIs which return a struct in
* which the last element is an array of undefined length. The caller
* of this type of API is expected to know the length of the array
* that will be returned and allocate a suitable buffer to contain the
* returned data. C99 refers to these variable length objects as
* structs containing flexible array members.
*
* This macro is safe to use on arguments with side effects.
*
* Returns -1 on failure, 0 on success
*/
# define VIR_ALLOC_VAR_QUIET(ptr, type, count) \
virAllocVar(&(ptr), sizeof(*(ptr)), sizeof(type), (count), false, 0, NULL, NULL, 0)
/**
* VIR_FREE:
* @ptr: pointer holding address to be freed
*
* Free the memory stored in 'ptr' and update to point
* to NULL.
*
* This macro is safe to use on arguments with side effects.
*/
/* The ternary ensures that ptr is a non-const pointer and not an
* integer type, all while evaluating ptr only once. This gives us
* extra compiler safety when compiling under gcc.
*/
# define VIR_FREE(ptr) virFree(1 ? (void *) &(ptr) : (ptr))
/**
* VIR_DISPOSE_N:
* @ptr: pointer holding address to be cleared and freed
* @count: count of elements in @ptr
*
* Clear the memory of the array of elemets pointed to by 'ptr' of 'count'
* elements and free it. Update the pointer/count to NULL/0.
*
* This macro is safe to use on arguments with side effects.
*/
# define VIR_DISPOSE_N(ptr, count) virDispose(1 ? (void *) &(ptr) : (ptr), 0, \
sizeof(*(ptr)), &(count))
/**
* VIR_DISPOSE_STRING:
* @ptr: pointer to a string to be cleared and freed
*
* Clears the string and frees the corresponding memory.
*
* This macro is not safe to be used on arguments with side effects.
*/
# define VIR_DISPOSE_STRING(ptr) virDispose(1 ? (void *) &(ptr) : (ptr), \
(ptr) ? strlen((ptr)) : 0, 1, NULL)
/**
* VIR_DISPOSE:
* @ptr: pointer to memory to be cleared and freed
*
* Clears and frees the corresponding memory.
*
* This macro is safe to be used on arguments with side effects.
*/
# define VIR_DISPOSE(ptr) virDispose(1 ? (void *) &(ptr) : (ptr), 1, \
sizeof(*(ptr)), NULL)
void virAllocTestInit(void);
int virAllocTestCount(void);
void virAllocTestOOM(int n, int m);
void virAllocTestHook(void (*func)(int, void*), void *data);
#endif /* __VIR_MEMORY_H_ */