util-lib: split out allocation calls into alloc-util.[ch]

1 files changed, 108 insertions, 0 deletions

diff --git a/src/basic/alloc-util.h b/src/basic/alloc-util.h
new file mode 100644
index 0000000000..12b602e185
--- /dev/null
+++ b/src/basic/alloc-util.h
@@ -0,0 +1,108 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <alloca.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "macro.h"
+
+#define new(t, n) ((t*) malloc_multiply(sizeof(t), (n)))
+
+#define new0(t, n) ((t*) calloc((n), sizeof(t)))
+
+#define newa(t, n) ((t*) alloca(sizeof(t)*(n)))
+
+#define newa0(t, n) ((t*) alloca0(sizeof(t)*(n)))
+
+#define newdup(t, p, n) ((t*) memdup_multiply(p, sizeof(t), (n)))
+
+#define malloc0(n) (calloc(1, (n)))
+
+static inline void *mfree(void *memory) {
+        free(memory);
+        return NULL;
+}
+
+void* memdup(const void *p, size_t l) _alloc_(2);
+
+static inline void freep(void *p) {
+        free(*(void**) p);
+}
+
+#define _cleanup_free_ _cleanup_(freep)
+
+_malloc_  _alloc_(1, 2) static inline void *malloc_multiply(size_t a, size_t b) {
+        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
+                return NULL;
+
+        return malloc(a * b);
+}
+
+_alloc_(2, 3) static inline void *realloc_multiply(void *p, size_t a, size_t b) {
+        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
+                return NULL;
+
+        return realloc(p, a * b);
+}
+
+_alloc_(2, 3) static inline void *memdup_multiply(const void *p, size_t a, size_t b) {
+        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
+                return NULL;
+
+        return memdup(p, a * b);
+}
+
+void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size);
+void* greedy_realloc0(void **p, size_t *allocated, size_t need, size_t size);
+
+#define GREEDY_REALLOC(array, allocated, need)                          \
+        greedy_realloc((void**) &(array), &(allocated), (need), sizeof((array)[0]))
+
+#define GREEDY_REALLOC0(array, allocated, need)                         \
+        greedy_realloc0((void**) &(array), &(allocated), (need), sizeof((array)[0]))
+
+#define alloca0(n)                                      \
+        ({                                              \
+                char *_new_;                            \
+                size_t _len_ = n;                       \
+                _new_ = alloca(_len_);                  \
+                (void *) memset(_new_, 0, _len_);       \
+        })
+
+/* It's not clear what alignment glibc/gcc alloca() guarantee, hence provide a guaranteed safe version */
+#define alloca_align(size, align)                                       \
+        ({                                                              \
+                void *_ptr_;                                            \
+                size_t _mask_ = (align) - 1;                            \
+                _ptr_ = alloca((size) + _mask_);                        \
+                (void*)(((uintptr_t)_ptr_ + _mask_) & ~_mask_);         \
+        })
+
+#define alloca0_align(size, align)                                      \
+        ({                                                              \
+                void *_new_;                                            \
+                size_t _size_ = (size);                                 \
+                _new_ = alloca_align(_size_, (align));                  \
+                (void*)memset(_new_, 0, _size_);                        \
+        })