lib/memcat_p.c

Source file repositories/reference/linux-study-clean/lib/memcat_p.c

File Facts

System
Linux kernel
Corpus path
lib/memcat_p.c
Extension
.c
Size
753 bytes
Lines
35
Domain
Kernel Services
Bucket
lib
Inferred role
Kernel Services: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0

#include <linux/slab.h>

/*
 * Merge two NULL-terminated pointer arrays into a newly allocated
 * array, which is also NULL-terminated. Nomenclature is inspired by
 * memset_p() and memcat() found elsewhere in the kernel source tree.
 */
void **__memcat_p(void **a, void **b)
{
	void **p = a, **new;
	int nr;

	/* count the elements in both arrays */
	for (nr = 0, p = a; *p; nr++, p++)
		;
	for (p = b; *p; nr++, p++)
		;
	/* one for the NULL-terminator */
	nr++;

	new = kmalloc_array(nr, sizeof(void *), GFP_KERNEL);
	if (!new)
		return NULL;

	/* nr -> last index; p points to NULL in b[] */
	for (nr--; nr >= 0; nr--, p = p == b ? &a[nr] : p - 1)
		new[nr] = *p;

	return new;
}
EXPORT_SYMBOL_GPL(__memcat_p);

Annotation

Implementation Notes