|
Message-Id: <20200801144658.6634-1-ariadne@dereferenced.org> Date: Sat, 1 Aug 2020 08:46:58 -0600 From: Ariadne Conill <ariadne@...eferenced.org> To: musl@...ts.openwall.com Cc: Ariadne Conill <ariadne@...eferenced.org> Subject: [PATCH] implement recallocarray(3) This OpenBSD extension is similar to reallocarray(3), but zero-initializes the new memory area. This extension is placed in _BSD_SOURCE, like reallocarray(3). This patch depends on reallocarray(3) already being present, and will not compile without it. --- include/stdlib.h | 1 + src/malloc/recallocarray.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 34 insertions(+) create mode 100644 src/malloc/recallocarray.c diff --git a/include/stdlib.h b/include/stdlib.h index b54a051f..a0412ad4 100644 --- a/include/stdlib.h +++ b/include/stdlib.h @@ -146,6 +146,7 @@ int clearenv(void); #define WCOREDUMP(s) ((s) & 0x80) #define WIFCONTINUED(s) ((s) == 0xffff) void *reallocarray (void *, size_t, size_t); +void *recallocarray (void *, size_t, size_t, size_t); #endif #ifdef _GNU_SOURCE diff --git a/src/malloc/recallocarray.c b/src/malloc/recallocarray.c new file mode 100644 index 00000000..c1370edc --- /dev/null +++ b/src/malloc/recallocarray.c @@ -0,0 +1,33 @@ +#define _BSD_SOURCE +#include <errno.h> +#include <stdlib.h> +#include <string.h> + +void *recallocarray(void *ptr, size_t om, size_t m, size_t n) +{ + void *newptr; + size_t old_size, new_size; + + if (n && m > -1 / n) { + errno = ENOMEM; + return 0; + } + new_size = m * n; + + if (n && om > -1 / n) { + errno = EINVAL; + return 0; + } + old_size = om * n; + + if (new_size <= old_size) { + memset((char *) ptr + new_size, 0, old_size - new_size); + } + + newptr = reallocarray(ptr, m, n); + if (new_size > old_size) { + memset((char *) ptr + old_size, 0, new_size - old_size); + } + + return newptr; +} -- 2.28.0
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.