[commit] master: rewrite nonsensical struct packing magic

[Oswald Buddenhagen via isync-devel]

commit 6010fe104ef2a3e91335fdb7e686939d6af82a46
Author: Oswald Buddenhagen <o...@users.sf.net>
Date:   Fri Nov 15 20:20:45 2019 +0100

    rewrite nonsensical struct packing magic
    
    this couldn't have possibly worked - the alignment also determines the
    sizeof, thus defeating the intent of the packing.

 src/common.h | 24 +++++++++++++-----------
 src/util.c   |  3 ++-
 2 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/common.h b/src/common.h
index c834cb1..c00495f 100644
--- a/src/common.h
+++ b/src/common.h
@@ -47,12 +47,10 @@ typedef unsigned long ulong;
 # define ATTR_UNUSED __attribute__((unused))
 # define ATTR_NORETURN __attribute__((noreturn))
 # define ATTR_PRINTFLIKE(fmt,var) __attribute__((format(printf,fmt,var)))
-# define ATTR_PACKED(ref) __attribute__((packed,aligned(sizeof(ref))))
 #else
 # define ATTR_UNUSED
 # define ATTR_NORETURN
 # define ATTR_PRINTFLIKE(fmt,var)
-# define ATTR_PACKED(ref)
 #endif
 
 #if defined(__clang__)
@@ -137,7 +135,7 @@ void flushn( void );
 typedef struct string_list {
        struct string_list *next;
        char string[1];
-} ATTR_PACKED(void *) string_list_t;
+} string_list_t;
 
 void add_string_list_n( string_list_t **list, const char *str, uint len );
 void add_string_list( string_list_t **list, const char *str );
@@ -176,22 +174,26 @@ int map_name( const char *arg, char **result, uint 
reserve, const char *in, cons
        typedef struct { \
                T *data; \
                uint size; \
-       } ATTR_PACKED(T *) T##_array_t; \
-       typedef struct { \
+       } T##_array_t; \
+       typedef union { \
                T##_array_t array; \
-               uint alloc; \
-       } ATTR_PACKED(T *) T##_array_alloc_t; \
+               struct { \
+                       T *dummy_data; \
+                       uint dummy_size; \
+                       uint alloc; \
+               } extra; \
+       } T##_array_alloc_t; \
        static INLINE T *T##_array_append( T##_array_alloc_t *arr ) \
        { \
-               if (arr->array.size == arr->alloc) { \
-                       arr->alloc = arr->alloc * 2 + 100; \
-                       arr->array.data = nfrealloc( arr->array.data, 
arr->alloc * sizeof(T) ); \
+               if (arr->array.size == arr->extra.alloc) { \
+                       arr->extra.alloc = arr->extra.alloc * 2 + 100; \
+                       arr->array.data = nfrealloc( arr->array.data, 
arr->extra.alloc * sizeof(T) ); \
                } \
                return &arr->array.data[arr->array.size++]; \
        }
 
 #define ARRAY_INIT(arr) \
-       do { (arr)->array.data = NULL; (arr)->array.size = (arr)->alloc = 0; } 
while (0)
+       do { (arr)->array.data = NULL; (arr)->array.size = (arr)->extra.alloc = 
0; } while (0)
 
 #define ARRAY_SQUEEZE(arr) \
        do { \
diff --git a/src/util.c b/src/util.c
index 08443de..c6c597c 100644
--- a/src/util.c
+++ b/src/util.c
@@ -23,6 +23,7 @@
 #include "common.h"
 
 #include <assert.h>
+#include <stddef.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -174,7 +175,7 @@ add_string_list_n( string_list_t **list, const char *str, 
uint len )
 {
        string_list_t *elem;
 
-       elem = nfmalloc( sizeof(*elem) + len );
+       elem = nfmalloc( offsetof(string_list_t, string) + len + 1 );
        elem->next = *list;
        *list = elem;
        memcpy( elem->string, str, len );


_______________________________________________
isync-devel mailing list
isync-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/isync-devel