[libvirt] [PATCH] virt-aa-helper: remove replace_string and use virStringReplace instead

[Andrea Bolognani]

On Fri, 2016-05-13 at 10:55 +0200, Pavel Hrdina wrote:
> Signed-off-by: Pavel Hrdina <phrdina at redhat.com>
> ---
>  src/security/virt-aa-helper.c | 76 +++++--------------------------------------
>  1 file changed, 9 insertions(+), 67 deletions(-)
> 
> diff --git a/src/security/virt-aa-helper.c b/src/security/virt-aa-helper.c
> index 7eeb4ef..537e89d 100644
> --- a/src/security/virt-aa-helper.c
> +++ b/src/security/virt-aa-helper.c
> @@ -148,62 +148,6 @@ vah_info(const char *str)
>  }
>  
>  /*
> - * Replace @oldstr in @orig with @repstr
> - * @len is number of bytes allocated for @orig. Assumes @orig, @oldstr and
> - * @repstr are null terminated
> - */
> -static int
> -replace_string(char *orig, const size_t len, const char *oldstr,
> -               const char *repstr)
> -{
> -    int idx;
> -    char *pos = NULL;
> -    char *tmp = NULL;
> -
> -    if ((pos = strstr(orig, oldstr)) == NULL) {
> -        vah_error(NULL, 0, _("could not find replacement string"));
> -        return -1;
> -    }
> -
> -    if (VIR_ALLOC_N_QUIET(tmp, len) < 0) {
> -        vah_error(NULL, 0, _("could not allocate memory for string"));
> -        return -1;
> -    }
> -    tmp[0] = '\0';
> -
> -    idx = abs(pos - orig);
> -
> -    /* copy everything up to oldstr */
> -    strncat(tmp, orig, idx);
> -
> -    /* add the replacement string */
> -    if (strlen(tmp) + strlen(repstr) > len - 1) {
> -        vah_error(NULL, 0, _("not enough space in target buffer"));
> -        VIR_FREE(tmp);
> -        return -1;
> -    }
> -    strcat(tmp, repstr);
> -
> -    /* add everything after oldstr */
> -    if (strlen(tmp) + strlen(orig) - (idx + strlen(oldstr)) > len - 1) {
> -        vah_error(NULL, 0, _("not enough space in target buffer"));
> -        VIR_FREE(tmp);
> -        return -1;
> -    }
> -    strncat(tmp, orig + idx + strlen(oldstr),
> -            strlen(orig) - (idx + strlen(oldstr)));
> -
> -    if (virStrcpy(orig, tmp, len) == NULL) {
> -        vah_error(NULL, 0, _("error replacing string"));
> -        VIR_FREE(tmp);
> -        return -1;
> -    }
> -    VIR_FREE(tmp);
> -
> -    return 0;
> -}
> -
> -/*
>   * run an apparmor_parser command
>   */
>  static int
> @@ -340,6 +284,7 @@ create_profile(const char *profile, const char *profile_name,
>      char *pcontent = NULL;
>      char *replace_name = NULL;
>      char *replace_files = NULL;
> +    char *tmp = NULL;
>      const char *template_name = "\nprofile LIBVIRT_TEMPLATE";
>      const char *template_end = "\n}";
>      int tlen, plen;
> @@ -412,19 +357,16 @@ create_profile(const char *profile, const char *profile_name,
>          goto clean_replace;
>      }
>  
> -    if (VIR_ALLOC_N_QUIET(pcontent, plen) < 0) {
> -        vah_error(NULL, 0, _("could not allocate memory for profile"));
> -        goto clean_replace;
> -    }
> -    pcontent[0] = '\0';
> -    strcpy(pcontent, tcontent);
> -
> -    if (replace_string(pcontent, plen, template_name, replace_name) < 0)
> +    if (!(pcontent = virStringReplace(tcontent, template_name, replace_name)))
>          goto clean_all;
>  
> -    if ((virtType != VIR_DOMAIN_VIRT_LXC) &&
> -            replace_string(pcontent, plen, template_end, replace_files) < 0)
> -        goto clean_all;
> +    if (virtType != VIR_DOMAIN_VIRT_LXC) {
> +        if (!(tmp = virStringReplace(pcontent, template_end, replace_files)))
> +            goto clean_all;
> +        VIR_FREE(pcontent);
> +        pcontent = tmp;
> +        tmp = NULL;
> +    }
>  
>      /* write the file */
>      if ((fd = open(profile, O_CREAT | O_EXCL | O_WRONLY, 0644)) == -1) {

ACK

As a side note, the use of cleanup labels could probably be simplified
a lot here, if you feel like doing that in a separate patch...

-- 
Andrea Bolognani
Software Engineer - Virtualization Team