Re: ldconfig/prebind.c - remove dead assignments

[Jérémie Courrèges-Anglas]

Kenneth R Westerback <kwesterb...@rogers.com> writes:

> On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas wrote:
>> David Hill <dh...@mindcry.org> writes:
>> 
>> > remove unused variables.
>> 
>> Makes sense.  ok?
>> 

[...]

>> >    lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
>> > -  len = read(fd, &footer, sizeof(struct prebind_footer));
>> > +  read(fd, &footer, sizeof(struct prebind_footer));
>
> Here I would consider actually using len to check for failure. And of
> course changing the type of len to ssize_t to allow such checking.
>
> .... Ken

Sure (assuming that an undetected lseek() error would be caught by
read()).

Index: prebind.c
===================================================================
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -r1.21 prebind.c
--- prebind.c   5 Jul 2013 21:10:50 -0000       1.21
+++ prebind.c   14 Jul 2013 13:04:19 -0000
@@ -475,12 +475,10 @@ done:
 int
 elf_check_note(void *buf, Elf_Phdr *phdr)
 {
-       Elf_Ehdr *ehdr;
        u_long address;
        u_int *pint;
        char *osname;
 
-       ehdr = (Elf_Ehdr *)buf;
        address = phdr->p_offset;
        pint = (u_int *)((char *)buf + address);
        osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1715,7 +1713,7 @@ elf_write_lib(struct elf_object *object,
        u_int32_t next_start, *fixuptab = NULL;
        struct stat ifstat;
        off_t base_offset;
-       size_t len;
+       ssize_t len;
        int fd = -1, i;
        int readonly = 0;
 
@@ -1733,6 +1731,11 @@ elf_write_lib(struct elf_object *object,
        }
        lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
        len = read(fd, &footer, sizeof(struct prebind_footer));
+       if (len == -1) {
+               perror(object->load_name);
+               close(fd);
+               return 1;
+       }
 
        if (fstat(fd, &ifstat) == -1) {
                perror(object->load_name);
@@ -2213,7 +2216,6 @@ void
 copy_oldsymcache(int objidx, void *prebind_map)
 {
        struct prebind_footer *footer;
-       struct elf_object *object;
        struct elf_object *tobj;
        struct symcache_noflag *tcache;
        struct symcachetab *symcache;
@@ -2222,8 +2224,6 @@ copy_oldsymcache(int objidx, void *prebi
        u_int32_t offset;
        u_int32_t *poffset;
        struct nameidx *nameidx;
-
-       object = objarray[objidx].obj;
 
        poffset = (u_int32_t *)prebind_map;
        c = prebind_map;