jffs2reader: introduce ADD_BYTES macro

This macro is dedicated to get rid of the compiler errors:
	lvalue required as left operand of assignment

Signed-off-by: Alexey Dokuchaev <danfe@nsu.ru>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

diff --git a/jffs2reader.c b/jffs2reader.c
index 1a211dbfb34762792be7d36ffdfe23707b8dfc67..ef9dbe3c68a2cce3e58e211cbcbdcaa3dc5b33d3 100644 (file)
--- a/jffs2reader.c
+++ b/jffs2reader.c
@@ -88,6 +88,9 @@ BUGS:
 #define MINOR(dev) ((dev)&0xff)
 #endif
 
+/* macro to avoid "lvalue required as left operand of assignment" error */
+#define ADD_BYTES(p, n)                ((p) = (typeof(p))((char *)(p) + (n)))
+
 #define DIRENT_INO(dirent) ((dirent) !=NULL ? je32_to_cpu((dirent)->ino) : 0)
 #define DIRENT_PINO(dirent) ((dirent) !=NULL ? je32_to_cpu((dirent)->pino) : 0)
 
@@ -441,7 +444,7 @@ struct jffs2_raw_inode *find_raw_inode(char *o, size_t size, uint32_t ino)
 
        do {
                while (n < e && je16_to_cpu(n->u.magic) != JFFS2_MAGIC_BITMASK)
-                       ((char *) n) += 4;
+                       ADD_BYTES(n, 4);
 
                if (n < e && je16_to_cpu(n->u.magic) == JFFS2_MAGIC_BITMASK) {
                        if (je16_to_cpu(n->u.nodetype) == JFFS2_NODETYPE_INODE &&
@@ -459,7 +462,7 @@ struct jffs2_raw_inode *find_raw_inode(char *o, size_t size, uint32_t ino)
                                        return (&(n->i));
                        }
 
-                       ((char *) n) += ((je32_to_cpu(n->u.totlen) + 3) & ~3);
+                       ADD_BYTES(n, ((je32_to_cpu(n->u.totlen) + 3) & ~3));
                } else
                        n = (union jffs2_node_union *) o;       /* we're at the end, rewind to the beginning */
 
@@ -509,7 +512,7 @@ struct dir *collectdir(char *o, size_t size, uint32_t ino, struct dir *d)
 
        do {
                while (n < e && je16_to_cpu(n->u.magic) != JFFS2_MAGIC_BITMASK)
-                       ((char *) n) += 4;
+                       ADD_BYTES(n, 4);
 
                if (n < e && je16_to_cpu(n->u.magic) == JFFS2_MAGIC_BITMASK) {
                        if (je16_to_cpu(n->u.nodetype) == JFFS2_NODETYPE_DIRENT &&
@@ -532,7 +535,7 @@ struct dir *collectdir(char *o, size_t size, uint32_t ino, struct dir *d)
                                }
                        }
 
-                       ((char *) n) += ((je32_to_cpu(n->u.totlen) + 3) & ~3);
+                       ADD_BYTES(n, ((je32_to_cpu(n->u.totlen) + 3) & ~3));
                } else
                        n = (union jffs2_node_union *) o;       /* we're at the end, rewind to the beginning */
 
@@ -596,7 +599,7 @@ struct jffs2_raw_dirent *resolvedirent(char *o, size_t size,
 
        do {
                while (n < e && je16_to_cpu(n->u.magic) != JFFS2_MAGIC_BITMASK)
-                       ((char *) n) += 4;
+                       ADD_BYTES(n, 4);
 
                if (n < e && je16_to_cpu(n->u.magic) == JFFS2_MAGIC_BITMASK) {
                        if (je16_to_cpu(n->u.nodetype) == JFFS2_NODETYPE_DIRENT &&
@@ -613,7 +616,7 @@ struct jffs2_raw_dirent *resolvedirent(char *o, size_t size,
                                }
                        }
 
-                       ((char *) n) += ((je32_to_cpu(n->u.totlen) + 3) & ~3);
+                       ADD_BYTES(n, ((je32_to_cpu(n->u.totlen) + 3) & ~3));
                } else
                        return dd;
        } while (1);