Re: [libvirt] [PATCH RFC 1/2] viralloc: Report OOM error on failure

In nearly all cases of calling VIR_ALLOC*, VIR_REALLOC_N, VIR_EXPAND_N, VIR_RESIZE_N, VIR_*_ELEMENT etc. we want to report OOM error, so our source code base is full of: if (VIR_ALLOC(somePtr) < 0) { virReportOOMError(); goto cleanup; } or similar. Moreover, for those few cases where we don't want to report OOM error (e.g. virReportOOMError() itself) a new VIR_ALLOC_NOOOM macro is being introduced. ---

diff --git a/src/util/viralloc.h b/src/util/viralloc.h index 7be7f82..30ffe15 100644 --- a/src/util/viralloc.h +++ b/src/util/viralloc.h @@ -46,7 +46,7 @@ /* Don't call these directly - use the macros below */ -int virAlloc(void *ptrptr, size_t size) ATTRIBUTE_RETURN_CHECK +int virAlloc(void *ptrptr, size_t size, bool report) ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1); int virAllocN(void *ptrptr, size_t size, size_t count) ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NONNULL(1); @@ -76,13 +76,16 @@ void virFree(void *ptrptr) 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. + * Allocate sizeof(*ptr) bytes of memory and store the + * address of allocated memory in 'ptr'. Fill the newly + * allocated memory with zeros. If there's a failure, + * OOM error is reported. The VIR_ALLOC_NOOOM macro + * behaves the same except the OOM error reporting. * * Returns -1 on failure, 0 on success */ -# define VIR_ALLOC(ptr) virAlloc(&(ptr), sizeof(*(ptr))) +# define VIR_ALLOC(ptr) virAlloc(&(ptr), sizeof(*(ptr)), true) +# define VIR_ALLOC_NOOOM(ptr) virAlloc(&(ptr), sizeof(*(ptr)), true)

/** * VIR_ALLOC_N: diff --git a/src/util/virerror.c b/src/util/virerror.c index c30642a..c033129 100644 --- a/src/util/virerror.c +++ b/src/util/virerror.c @@ -204,7 +204,7 @@ virLastErrorObject(void) virErrorPtr err; err = virThreadLocalGet(&virLastErr); if (!err) { - if (VIR_ALLOC(err) < 0) + if (VIR_ALLOC_NOOOM(err) < 0) return NULL; if (virThreadLocalSet(&virLastErr, err) < 0) VIR_FREE(err);