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SubjectRe: [PATCH] Implement file posix capabilities
Oops, it's my stupid bug.

> Ah, this actually makes sense. The setfcaps usage() statement does
>
> for (i=0; _cap_names[i]; i++) {
> printf...
>
> so it expects _cap_names to end with a terminating NULL, but that
> doesn't seem to be the case in cap_names.h in libcap.
>
> KaiGai, perhaps setfcaps should do something like
>
> diff setfcaps.c.orig setfcaps.c
> 25c25
> < for (i=0; _cap_names[i]; i++)
> ---
>> for (i=0; i<__CAP_BITS; i++)

I fixed the matter as follows:

[kaigai@masu libcap-1.10.kg]$ env LANG=C svn diff -r2:3
Index: libcap/_makenames.c
===================================================================
--- libcap/_makenames.c (revision 2)
+++ libcap/_makenames.c (revision 3)
@@ -45,6 +45,7 @@
"#define __CAP_BITS %d\n"
"\n"
"#ifdef LIBCAP_PLEASE_INCLUDE_ARRAY\n"
+ " int const _cap_names_num = __CAP_BITS;\n"
" char const *_cap_names[__CAP_BITS] = {\n", maxcaps);

for (i=0; i<maxcaps; ++i) {
Index: libcap/include/sys/capability.h
===================================================================
--- libcap/include/sys/capability.h (revision 2)
+++ libcap/include/sys/capability.h (revision 3)
@@ -113,6 +113,7 @@
extern int capgetp(pid_t pid, cap_t cap_d);
extern int capsetp(pid_t pid, cap_t cap_d);
extern char const *_cap_names[];
+extern int const _cap_names_num;

#endif /* !defined(_POSIX_SOURCE) */

Index: progs/setfcaps.c
===================================================================
--- progs/setfcaps.c (revision 2)
+++ progs/setfcaps.c (revision 3)
@@ -14,6 +14,7 @@
#include <errno.h>
#include <sys/capability.h>

+extern int const _cap_names_num;
extern char const *_cap_names[];

static void usage() {
@@ -21,8 +22,8 @@
int i;

fputs(message, stderr);
- for (i=0; _cap_names[i]; i++)
- fprintf(stderr, "%s%s", i%4==0 ? "\n\t" : ", ", _cap_names[i]);
+ for (i=0; i < _cap_names_num; i++)
+ fprintf(stderr, "%s%s", i%4==0 ? "\n\t" : ", ", _cap_names[i]);
fputc('\n', stderr);
exit(0);
}
[kaigai@masu libcap-1.10.kg]$
Because '__CAP_BITS' is decided at compiling time, I think it's not
appropriate to indicate the length of _cap_names[] which is linked
at run time.
Therefore, I add a new integer variable _cap_names_num to represent
the length of _cap_names at run time.

You can download it from http://www.kaigai.gr.jp/index.php?FrontPage#b556e50d

Thanks,
--
KaiGai Kohei <kaigai@kaigai.gr.jp>
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