diff options
Diffstat (limited to 'lib/string.c')
| -rw-r--r-- | lib/string.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/lib/string.c b/lib/string.c index 2c0900a5d51a..453f35994eb6 100644 --- a/lib/string.c +++ b/lib/string.c @@ -27,6 +27,7 @@ #include <linux/export.h> #include <linux/bug.h> #include <linux/errno.h> +#include <linux/slab.h> #include <asm/byteorder.h> #include <asm/word-at-a-time.h> @@ -890,6 +891,36 @@ void *memscan(void *addr, int c, size_t size) EXPORT_SYMBOL(memscan); #endif +/* + * 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); + #ifndef __HAVE_ARCH_STRSTR /** * strstr - Find the first substring in a %NUL terminated string |