Adding upstream version 241.upstream/241upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 162 insertions, 0 deletions

diff --git a/src/basic/alloc-util.h b/src/basic/alloc-util.h
new file mode 100644
index 0000000..893a123
--- /dev/null
+++ b/src/basic/alloc-util.h
@@ -0,0 +1,162 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+#include <alloca.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "macro.h"
+
+typedef void (*free_func_t)(void *p);
+
+/* If for some reason more than 4M are allocated on the stack, let's abort immediately. It's better than
+ * proceeding and smashing the stack limits. Note that by default RLIMIT_STACK is 8M on Linux. */
+#define ALLOCA_MAX (4U*1024U*1024U)
+
+#define new(t, n) ((t*) malloc_multiply(sizeof(t), (n)))
+
+#define new0(t, n) ((t*) calloc((n) ?: 1, sizeof(t)))
+
+#define newa(t, n)                                                      \
+        ({                                                              \
+                size_t _n_ = n;                                         \
+                assert(!size_multiply_overflow(sizeof(t), _n_));        \
+                assert(sizeof(t)*_n_ <= ALLOCA_MAX);                    \
+                (t*) alloca(sizeof(t)*_n_);                             \
+        })
+
+#define newa0(t, n)                                                     \
+        ({                                                              \
+                size_t _n_ = n;                                         \
+                assert(!size_multiply_overflow(sizeof(t), _n_));        \
+                assert(sizeof(t)*_n_ <= ALLOCA_MAX);                    \
+                (t*) alloca0(sizeof(t)*_n_);                            \
+        })
+
+#define newdup(t, p, n) ((t*) memdup_multiply(p, sizeof(t), (n)))
+
+#define newdup_suffix0(t, p, n) ((t*) memdup_suffix0_multiply(p, sizeof(t), (n)))
+
+#define malloc0(n) (calloc(1, (n)))
+
+static inline void *mfree(void *memory) {
+        free(memory);
+        return NULL;
+}
+
+#define free_and_replace(a, b)                  \
+        ({                                      \
+                free(a);                        \
+                (a) = (b);                      \
+                (b) = NULL;                     \
+                0;                              \
+        })
+
+void* memdup(const void *p, size_t l) _alloc_(2);
+void* memdup_suffix0(const void *p, size_t l) _alloc_(2);
+
+#define memdupa(p, l)                           \
+        ({                                      \
+                void *_q_;                      \
+                size_t _l_ = l;                 \
+                assert(_l_ <= ALLOCA_MAX);      \
+                _q_ = alloca(_l_);              \
+                memcpy(_q_, p, _l_);            \
+        })
+
+#define memdupa_suffix0(p, l)                   \
+        ({                                      \
+                void *_q_;                      \
+                size_t _l_ = l;                 \
+                assert(_l_ <= ALLOCA_MAX);      \
+                _q_ = alloca(_l_ + 1);          \
+                ((uint8_t*) _q_)[_l_] = 0;      \
+                memcpy(_q_, p, _l_);            \
+        })
+
+static inline void freep(void *p) {
+        free(*(void**) p);
+}
+
+#define _cleanup_free_ _cleanup_(freep)
+
+static inline bool size_multiply_overflow(size_t size, size_t need) {
+        return _unlikely_(need != 0 && size > (SIZE_MAX / need));
+}
+
+_malloc_  _alloc_(1, 2) static inline void *malloc_multiply(size_t size, size_t need) {
+        if (size_multiply_overflow(size, need))
+                return NULL;
+
+        return malloc(size * need ?: 1);
+}
+
+#if !HAVE_REALLOCARRAY
+_alloc_(2, 3) static inline void *reallocarray(void *p, size_t need, size_t size) {
+        if (size_multiply_overflow(size, need))
+                return NULL;
+
+        return realloc(p, size * need ?: 1);
+}
+#endif
+
+_alloc_(2, 3) static inline void *memdup_multiply(const void *p, size_t size, size_t need) {
+        if (size_multiply_overflow(size, need))
+                return NULL;
+
+        return memdup(p, size * need);
+}
+
+_alloc_(2, 3) static inline void *memdup_suffix0_multiply(const void *p, size_t size, size_t need) {
+        if (size_multiply_overflow(size, need))
+                return NULL;
+
+        return memdup_suffix0(p, size * need);
+}
+
+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;                       \
+                assert(_len_ <= ALLOCA_MAX);            \
+                _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;                            \
+                size_t _size_ = size;                                   \
+                assert(_size_ <= ALLOCA_MAX);                           \
+                _ptr_ = alloca(_size_ + _mask_);                        \
+                (void*)(((uintptr_t)_ptr_ + _mask_) & ~_mask_);         \
+        })
+
+#define alloca0_align(size, align)                                      \
+        ({                                                              \
+                void *_new_;                                            \
+                size_t _xsize_ = (size);                                \
+                _new_ = alloca_align(_xsize_, (align));                 \
+                (void*)memset(_new_, 0, _xsize_);                       \
+        })
+
+/* Takes inspiration from Rusts's Option::take() method: reads and returns a pointer, but at the same time resets it to
+ * NULL. See: https://doc.rust-lang.org/std/option/enum.Option.html#method.take */
+#define TAKE_PTR(ptr)                           \
+        ({                                      \
+                typeof(ptr) _ptr_ = (ptr);      \
+                (ptr) = NULL;                   \
+                _ptr_;                          \
+        })