SkMemory_malloc.cpp File Reference

#include "include/private/base/SkAssert.h"
#include "include/private/base/SkDebug.h"
#include "include/private/base/SkFeatures.h"
#include "include/private/base/SkMalloc.h"
#include <algorithm>
#include <cstdlib>

Go to the source code of this file.

Macros
#define	SK_DEBUGFAILF(fmt, ...)   SkASSERT((SkDebugf(fmt"\n", __VA_ARGS__), false))

Functions
static void	sk_out_of_memory (size_t size)
static void *	throw_on_failure (size_t size, void *p)
void	sk_abort_no_print ()
void	sk_out_of_memory (void)
void *	sk_realloc_throw (void *addr, size_t size)
void	sk_free (void *p)
void *	sk_malloc_flags (size_t size, unsigned flags)
size_t	sk_malloc_size (void *addr, size_t size)

Macro Definition Documentation

SK_DEBUGFAILF

#define SK_DEBUGFAILF	(		fmt,
			...
	)		SkASSERT((SkDebugf(fmt"\n", __VA_ARGS__), false))

Definition at line 35 of file SkMemory_malloc.cpp.

Function Documentation

sk_abort_no_print()

void sk_abort_no_print

(

void

)

Called internally if we hit an unrecoverable error. The platform implementation must not return, but should either throw an exception or otherwise exit.

Definition at line 56 of file SkMemory_malloc.cpp.

                         {
#if defined(SK_DEBUG) && defined(SK_BUILD_FOR_WIN)
    __fastfail(FAST_FAIL_FATAL_APP_EXIT);
#elif defined(__clang__)
    __builtin_trap();
#else
    abort();
#endif
}

sk_free()

void sk_free

(

void *

p

)

Free memory returned by sk_malloc(). It is safe to pass null.

Definition at line 83 of file SkMemory_malloc.cpp.

                      {
    // The guard here produces a performance improvement across many tests, and many platforms.
    // Removing the check was tried in skia cl 588037.
    if (p != nullptr) {
        free(p);
    }
}

sk_malloc_flags()

void * sk_malloc_flags	(	size_t	size,
		unsigned	flags
	)

Return a block of memory (at least 4-byte aligned) of at least the specified size. If the requested memory cannot be returned, either return nullptr or throw/exit, depending on the SK_MALLOC_THROW bit. If the allocation succeeds, the memory will be zero-initialized if the SK_MALLOC_ZERO_INITIALIZE bit was set.

To free the memory, call sk_free()

Definition at line 91 of file SkMemory_malloc.cpp.

                                                   {
    void* p;
    if (flags & SK_MALLOC_ZERO_INITIALIZE) {
        p = calloc(size, 1);
    } else {
#if defined(SK_BUILD_FOR_ANDROID_FRAMEWORK) && defined(__BIONIC__)
        /* TODO: After b/169449588 is fixed, we will want to change this to restore
         *       original behavior instead of always disabling the flag.
         * TODO: After b/158870657 is fixed and scudo is used globally, we can assert when an
         *       an error is returned.
         */
        // malloc() generally doesn't initialize its memory and that's a huge security hole,
        // so Android has replaced its malloc() with one that zeros memory,
        // but that's a huge performance hit for HWUI, so turn it back off again.
        (void)mallopt(M_THREAD_DISABLE_MEM_INIT, 1);
#endif
        p = malloc(size);
#if defined(SK_BUILD_FOR_ANDROID_FRAMEWORK) && defined(__BIONIC__)
        (void)mallopt(M_THREAD_DISABLE_MEM_INIT, 0);
#endif
    }
    if (flags & SK_MALLOC_THROW) {
        return throw_on_failure(size, p);
    } else {
        return p;
    }
}

sk_malloc_size()

size_t sk_malloc_size	(	void *	addr,
		size_t	size
	)

Return the size of the block of memory allocated in reality for a given pointer. The pointer passed must have been allocated using the sk_malloc_* or sk_realloc_* functions. The "size" parameter indicates the size originally requested when the memory block was allocated, and the value returned by this function must be bigger or equal to it.

Definition at line 119 of file SkMemory_malloc.cpp.

                                               {
    size_t completeSize = size;
 
    // Use the OS specific calls to find the actual capacity.
    #if defined(SK_BUILD_FOR_MAC) || defined(SK_BUILD_FOR_IOS)
        // TODO: remove the max, when the chrome implementation of malloc_size doesn't return 0.
        completeSize = std::max(malloc_size(addr), size);
    #elif defined(SK_BUILD_FOR_ANDROID) && __ANDROID_API__ >= 17
        completeSize = malloc_usable_size(addr);
        SkASSERT(completeSize >= size);
    #elif defined(SK_BUILD_FOR_UNIX)
        completeSize = malloc_usable_size(addr);
        SkASSERT(completeSize >= size);
    #elif defined(SK_BUILD_FOR_WIN)
        completeSize = _msize(addr);
        SkASSERT(completeSize >= size);
    #endif
 
    return completeSize;
}

sk_out_of_memory() [1/2]

static void sk_out_of_memory ( size_t  size )

inlinestatic

Definition at line 38 of file SkMemory_malloc.cpp.

                                                 {
    SK_DEBUGFAILF("sk_out_of_memory (asked for %zu bytes)",
                  size);
#if defined(SK_BUILD_FOR_AFL_FUZZ)
    exit(1);
#else
    abort();
#endif
}

sk_out_of_memory() [2/2]

void sk_out_of_memory

(

void

)

Called internally if we run out of memory. The platform implementation must not return, but should either throw an exception or otherwise exit.

Definition at line 66 of file SkMemory_malloc.cpp.

                            {
    SkDEBUGFAIL("sk_out_of_memory");
#if defined(SK_BUILD_FOR_AFL_FUZZ)
    exit(1);
#else
    abort();
#endif
}

sk_realloc_throw()

void * sk_realloc_throw	(	void *	buffer,
		size_t	size
	)

Same as standard realloc(), but this one never returns null on failure. It will throw if it fails. If size is 0, it will call sk_free on buffer and return null. (This behavior is implementation- defined for normal realloc. We follow what glibc does.)

Definition at line 75 of file SkMemory_malloc.cpp.

                                                {
    if (size == 0) {
        sk_free(addr);
        return nullptr;
    }
    return throw_on_failure(size, realloc(addr, size));
}

throw_on_failure()

static void * throw_on_failure ( size_t  size, void *  p  )

inlinestatic

Definition at line 48 of file SkMemory_malloc.cpp.

                                                           {
    if (size > 0 && p == nullptr) {
        // If we've got a nullptr here, the only reason we should have failed is running out of RAM.
        sk_out_of_memory(size);
    }
    return p;
}