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Re: Request for advise with struct stat, ACL, xattr, zlib (2nd try)

 libisofs/builder.c:209: warning: passing
 argument 2 of 'aaip_cleanout_st_mode' from
 incompatible pointer type

Is stat.st_mode not of type mode_t ?

The line in question is:

 aaip_cleanout_st_mode(a_text, &(info.st_mode), 4 | 16);

Argument number two is a component of
 struct stat info;

The function prototype is
 int aaip_cleanout_st_mode(char *acl_text, mode_t *st_mode, int flag);

Can somebody please have a look into
 struct stat.st_mode
is of different size than mode_t ?
The warning appears on amd64 and on i386.

Unfortunately yes:

/* Structure describing file characteristics.  */
struct stat
    __dev_t st_dev;             /* Device containing the file.  */
    __ino_t st_ino;             /* File serial number.  */
    __uint32_t st_mode;         /* File mode.  */
    __uint32_t st_nlink;        /* Link count.  */
    __uid_t st_uid;             /* User ID of the file's owner.  */
    __gid_t st_gid;             /* Group ID of the file's group.  */
    __dev_t st_rdev;            /* Device number, if device.  */
    struct timespec st_atim;            /* Time of last access.  */
    struct timespec st_mtim;            /* Time of last modification.  */
    struct timespec st_ctim;            /* Time of last status change.  */
    __off_t st_size;            /* Size of file, in bytes.  */
    __blkcnt_t st_blocks;       /* Number of 512-byte blocks allocated.  */
    __blksize_t st_blksize;     /* Optimal block size for I/O.  */
    __uint32_t st_flags;        /* User defined flags.  */
    __uint32_t st_gen;          /* Generation number.  */
    __quad_t __unused1[2];

Similar problem might be with nlink_t (16 bit also). Both are mandated by POSIX

IMO, we should fix our headers, but retain binary compatibility
which on little endian should be doable by

-    __uint32_t st_mode;        /* File mode.  */
-    __uint32_t st_nlink;       /* Link count.  */
+    __mode_t st_mode;		/* File mode.  */
+    __mode_t __pad_mode;	/* __mode_t is 16 bit, align to 32 bit to retain previous ABI */
+    __nlink_t st_nlink;	/* Link count.  */
+    __nlink_t __pad_nlink;	/* __nlink_t is 16 bit, align to 32 bit to retain previous ABI */

And the stat16_to_stat() should zero __pad_mode and __pad_nlink.

Aurelien, Cyril do you agree with this (eglibc) change ?


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