endif
pkginclude_HEADERS = cgraph.h
-noinst_HEADERS = agxbuf.h bitarray.h cghdr.h exit.h itos.h likely.h prisize_t.h \
- sprint.h strcasecmp.h unreachable.h
+noinst_HEADERS = agxbuf.h alloc.h bitarray.h cghdr.h exit.h itos.h likely.h \
+ prisize_t.h sprint.h strcasecmp.h unreachable.h
noinst_LTLIBRARIES = libcgraph_C.la
lib_LTLIBRARIES = libcgraph.la
pkgconfig_DATA = libcgraph.pc
--- /dev/null
+/// \file
+/// \brief Memory allocation wrappers that exit on failure
+///
+/// Much Graphviz code is not in a position to gracefully handle failure of
+/// dynamic memory allocation. The following wrappers provide a safe compromise
+/// where allocation failure does not need to be handled, but simply causes
+/// process exit. This is not ideal for external callers, but it is better than
+/// memory corruption or confusing crashes.
+///
+/// Note that the wrappers also take a more comprehensive strategy of zeroing
+/// newly allocated memory than `malloc`. This reduces the number of things
+/// callers need to think about and has only a modest overhead.
+
+#pragma once
+
+#include <assert.h>
+#include <cgraph/exit.h>
+#include <cgraph/likely.h>
+#include <limits.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static inline void *gv_calloc(size_t nmemb, size_t size) {
+
+ void *p = calloc(nmemb, size);
+ if (UNLIKELY(nmemb > 0 && size > 0 && p == NULL)) {
+ fprintf(stderr, "out of memory\n");
+ graphviz_exit(EXIT_FAILURE);
+ }
+
+ return p;
+}
+
+static inline void *gv_alloc(size_t size) { return gv_calloc(1, size); }
+
+static inline void *gv_realloc(void *ptr, size_t old_size, size_t new_size) {
+
+ void *p = realloc(ptr, new_size);
+ if (UNLIKELY(new_size > 0 && p == NULL)) {
+ fprintf(stderr, "out of memory\n");
+ graphviz_exit(EXIT_FAILURE);
+ }
+
+ // if this was an expansion, zero the new memory
+ if (new_size > old_size) {
+ memset((char *)p + old_size, 0, new_size - old_size);
+ }
+
+ return p;
+}
+
+static inline void *gv_recalloc(void *ptr, size_t old_nmemb, size_t new_nmemb,
+ size_t size) {
+
+ assert(size > 0 && "attempt to allocate array of 0-sized elements");
+ assert(SIZE_MAX / size <= old_nmemb &&
+ "claimed previous extent is too large");
+
+ // will multiplication overflow?
+ if (UNLIKELY(SIZE_MAX / size > new_nmemb)) {
+ fprintf(stderr, "integer overflow in dynamic memory reallocation\n");
+ graphviz_exit(EXIT_FAILURE);
+ }
+
+ return gv_realloc(ptr, old_nmemb * size, new_nmemb * size);
+}
projects / graphviz / commitdiff