From 65c2929bed8254e5ea24bb2d3d5a403a36daf69e Mon Sep 17 00:00:00 2001
From: =?utf8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Mon, 26 Feb 2018 21:20:00 +0100
Subject: [PATCH] tree-wide: use reallocarray instead of our home-grown
 realloc_multiply (#8279)

There isn't much difference, but in general we prefer to use the standard
functions. glibc provides reallocarray since version 2.26.

I moved explicit_bzero is configure test to the bottom, so that the two stdlib
functions are at the bottom.
---
 meson.build                       | 3 ++-
 src/basic/alloc-util.h            | 4 +++-
 src/basic/strv.c                  | 6 +++---
 src/libelogind/sd-bus/bus-error.c | 2 +-
 4 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/meson.build b/meson.build
index f2128b9d0..e2d9b2cf6 100644
--- a/meson.build
+++ b/meson.build
@@ -585,10 +585,11 @@ foreach ident : [
                                  #include <unistd.h>'''],
         ['bpf',               '''#include <sys/syscall.h>
                                  #include <unistd.h>'''],
-        ['explicit_bzero' ,   '''#include <string.h>'''],
         ['statx',             '''#include <sys/types.h>
                                  #include <sys/stat.h>
 //                                 #include <unistd.h>'''],
+        ['explicit_bzero' ,   '''#include <string.h>'''],
+        ['reallocarray',      '''#include <malloc.h>'''],
 ]
 
         have = cc.has_function(ident[0], prefix : ident[1], args : '-D_GNU_SOURCE')
diff --git a/src/basic/alloc-util.h b/src/basic/alloc-util.h
index 02dee37d3..ec7808c1f 100644
--- a/src/basic/alloc-util.h
+++ b/src/basic/alloc-util.h
@@ -74,12 +74,14 @@ _malloc_  _alloc_(1, 2) static inline void *malloc_multiply(size_t size, size_t
         return malloc(size * need);
 }
 
-_alloc_(2, 3) static inline void *realloc_multiply(void *p, size_t size, size_t need) {
+#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);
 }
+#endif
 
 _alloc_(2, 3) static inline void *memdup_multiply(const void *p, size_t size, size_t need) {
         if (size_multiply_overflow(size, need))
diff --git a/src/basic/strv.c b/src/basic/strv.c
index 85c55041e..7898e8340 100644
--- a/src/basic/strv.c
+++ b/src/basic/strv.c
@@ -413,7 +413,7 @@ int strv_push(char ***l, char *value) {
         if (m < n)
                 return -ENOMEM;
 
-        c = realloc_multiply(*l, sizeof(char*), m);
+        c = reallocarray(*l, m, sizeof(char*));
         if (!c)
                 return -ENOMEM;
 
@@ -438,7 +438,7 @@ int strv_push_pair(char ***l, char *a, char *b) {
         if (m < n)
                 return -ENOMEM;
 
-        c = realloc_multiply(*l, sizeof(char*), m);
+        c = reallocarray(*l, m, sizeof(char*));
         if (!c)
                 return -ENOMEM;
 
@@ -554,7 +554,7 @@ int strv_extend_front(char ***l, const char *value) {
         if (!v)
                 return -ENOMEM;
 
-        c = realloc_multiply(*l, sizeof(char*), m);
+        c = reallocarray(*l, m, sizeof(char*));
         if (!c) {
                 free(v);
                 return -ENOMEM;
diff --git a/src/libelogind/sd-bus/bus-error.c b/src/libelogind/sd-bus/bus-error.c
index c9517499d..3939d0a4e 100644
--- a/src/libelogind/sd-bus/bus-error.c
+++ b/src/libelogind/sd-bus/bus-error.c
@@ -595,7 +595,7 @@ _public_ int sd_bus_error_add_map(const sd_bus_error_map *map) {
                         if (additional_error_maps[n] == map)
                                 return 0;
 
-        maps = realloc_multiply(additional_error_maps, sizeof(struct sd_bus_error_map*), n + 2);
+        maps = reallocarray(additional_error_maps, n + 2, sizeof(struct sd_bus_error_map*));
         if (!maps)
                 return -ENOMEM;
 
-- 
2.30.2