NAME

       seccomp_merge - Merge two seccomp filters

SYNOPSIS

       #include <seccomp.h>

       typedef void * scmp_filter_ctx;

       int seccomp_merge(scmp_filter_ctx dst, scmp_filter_ctx src);

       Link with -lseccomp.

DESCRIPTION

       The  seccomp_merge()  function merges the seccomp filter in src with the filter in dst and
       stores the resulting in the dst  filter.   If  successfull,  the  src  seccomp  filter  is
       released  and  all internal memory assocated with the filter is freed; there is no need to
       call seccomp_release(3) on src and the caller should discard any references to the filter.

       In order to merge two seccomp filters, both filters must have the  same  attribute  values
       and no overlapping architectures.

RETURN VALUE

       Returns zero on success and negative values on failure.

EXAMPLES

       #include <seccomp.h>

       int main(int argc, char *argv[])
       {
            int rc = -1;
            scmp_filter_ctx ctx_32, ctx_64;

            ctx_32 = seccomp_init(SCMP_ACT_KILL);
            if (ctx_32 == NULL)
                 goto out_all;
            ctx_64 = seccomp_init(SCMP_ACT_KILL);
            if (ctx_64 == NULL)
                 goto out_all;

            if (seccomp_arch_exist(ctx_32, SCMP_ARCH_X86) == -EEXIST) {
                 rc = seccomp_arch_add(ctx_32, SCMP_ARCH_X86);
                 if (rc != 0)
                      goto out_all;
                 rc = seccomp_arch_remove(ctx_32, SCMP_ARCH_NATIVE);
                 if (rc != 0)
                      goto out_all;
            }
            if (seccomp_arch_exist(ctx_64, SCMP_ARCH_X86_64) == -EEXIST) {
                 rc = seccomp_arch_add(ctx_64, SCMP_ARCH_X86_64);
                 if (rc != 0)
                      goto out_all;
                 rc = seccomp_arch_remove(ctx_64, SCMP_ARCH_NATIVE);
                 if (rc != 0)
                      goto out_all;
            }

            /* ... */

            rc = seccomp_merge(ctx_64, ctx_32);
            if (rc != 0)
                 goto out_all;

            /* NOTE: the 'ctx_32' filter is no longer valid at this point */

            /* ... */

       out:
            seccomp_release(ctx_64);
            return -rc;
       out_all:
            seccomp_release(ctx_32);
            goto out;
       }

NOTES

       While  the  seccomp  filter  can be generated independent of the kernel, kernel support is
       required to load and enforce the seccomp filter generated by libseccomp.

       The libseccomp project site, with more information and the source code repository, can  be
       found  at  http://libseccomp.sf.net.   This library is currently under development, please
       report any bugs at the project site or directly to the author.

AUTHOR

       Paul Moore <paul@paul-moore.com>

SEE ALSO

       seccomp_init(3),    seccomp_reset(3),     seccomp_arch_add(3),     seccomp_arch_remove(3),
       seccomp_attr_get(3), seccomp_attr_set(3)