diff options
Diffstat (limited to 'xtables.c')
| -rw-r--r-- | xtables.c | 50 |
1 files changed, 28 insertions, 22 deletions
@@ -73,44 +73,50 @@ void basic_exit_err(enum xtables_exittype status, const char *msg, ...) exit(status); } - -void xtables_free_opts(int reset_offset) +void xtables_free_opts(int unused) { - if (xt_params->opts != xt_params->orig_opts) { - free(xt_params->opts); - xt_params->opts = xt_params->orig_opts; - if (reset_offset) - xt_params->option_offset = 0; - } + free(xt_params->opts); } -struct option *xtables_merge_options(struct option *oldopts, +struct option *xtables_merge_options(struct option *orig_opts, + struct option *oldopts, const struct option *newopts, unsigned int *option_offset) { - unsigned int num_old, num_new, i; - struct option *merge; + unsigned int num_oold = 0, num_old = 0, num_new = 0, i; + struct option *merge, *mp; if (newopts == NULL) return oldopts; - for (num_old = 0; oldopts[num_old].name; num_old++) ; + for (num_oold = 0; orig_opts[num_oold].name; num_oold++) ; + if (oldopts != NULL) + for (num_old = 0; oldopts[num_old].name; num_old++) ; for (num_new = 0; newopts[num_new].name; num_new++) ; + merge = malloc(sizeof(*mp) * (num_oold + num_old + num_new + 1)); + if (merge == NULL) + return NULL; + + /* Let the base options -[ADI...] have precedence over everything */ + memcpy(merge, orig_opts, sizeof(*mp) * num_oold); + mp = merge + num_oold; + + /* Second, the new options */ xt_params->option_offset += 256; *option_offset = xt_params->option_offset; + memcpy(mp, newopts, sizeof(*mp) * num_new); - merge = malloc(sizeof(struct option) * (num_new + num_old + 1)); - if (merge == NULL) - return NULL; - memcpy(merge, oldopts, num_old * sizeof(struct option)); - xtables_free_opts(0); /* Release any old options merged */ - for (i = 0; i < num_new; i++) { - merge[num_old + i] = newopts[i]; - merge[num_old + i].val += *option_offset; - } - memset(merge + num_old + num_new, 0, sizeof(struct option)); + for (i = 0; i < num_new; ++i, ++mp) + mp->val += *option_offset; + + /* Third, the old options */ + memcpy(mp, oldopts, sizeof(*mp) * num_old); + mp += num_old; + xtables_free_opts(0); + /* Clear trailing entry */ + memset(mp, 0, sizeof(*mp)); return merge; } |