Re: [PATCH] Use strtok_r instead of strsep in rust_get_disr_info

[Pedro Alves <palves at redhat dot com>]

(stepping in since this fixes a build breakage.)

On 06/29/2016 11:13 AM, Manish Goregaokar wrote:
> strsep doesn't exist on windows

"Windows", uppercase.

> 
> 2016-06-29  Manish Goregaokar  <manish@mozilla.com>
> 
> gdb/ChangeLog:
>     * rust-lang.c (rust_get_disr_info): Use strtok_r instead of strsep

Period at end of sentences.  Likewise on the commit log,
while at it.

> ---
>  gdb/rust-lang.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c
> index 23ddd5a..961fdca 100644
> --- a/gdb/rust-lang.c
> +++ b/gdb/rust-lang.c
> @@ -121,7 +121,7 @@ rust_get_disr_info (struct type *type, const
> gdb_byte *valaddr,
>    if (strncmp (TYPE_FIELD_NAME (type, 0), RUST_ENUM_PREFIX,
>             strlen (RUST_ENUM_PREFIX)) == 0)
>      {
> -      char *name, *tail, *token;
> +      char *tail, *token, *name, *last = NULL;

(I don't think you need to initialize this.  If you get
a warning about it, it's likely revealing a bug.)

>        unsigned long fieldno;
>        struct type *member_type;
>        LONGEST value;
> @@ -138,6 +138,8 @@ rust_get_disr_info (struct type *type, const
> gdb_byte *valaddr,
>        cleanup = make_cleanup (xfree, name);
>        tail = name + strlen (RUST_ENUM_PREFIX);
> 
> +      token = strtok_r (tail, "$", &last);
> +
>        /* The location of the value that doubles as a discriminant is
>           stored in the name of the field, as
>           RUST$ENCODED$ENUM$<fieldno>$<fieldno>$...$<variantname>
> @@ -145,7 +147,7 @@ rust_get_disr_info (struct type *type, const
> gdb_byte *valaddr,
>           traversed in order to find the field (which may be several
> fields deep)
>           and the variantname is the name of the variant of the case when the
>           field is zero.  */
> -      while ((token = strsep (&tail, "$")) != NULL)
> +      do
>          {
>        if (sscanf (token, "%lu", &fieldno) != 1)

We'll now reach here even if token is NULL the first time.

>          {
> @@ -159,10 +161,8 @@ rust_get_disr_info (struct type *type, const
> gdb_byte *valaddr,
> 
>            embedded_offset += TYPE_FIELD_BITPOS (member_type, fieldno) / 8;
>            member_type = TYPE_FIELD_TYPE (member_type, fieldno);
> -        }
> +        } while ((token = strtok_r (NULL, "$", &last)) != NULL);

IMO, this calls for a "for" loop instead of a do/while.  Like:

 -      while ((token = strsep (&tail, "$")) != NULL)
 +      for (token = strtok_r (tail, "$", &saveptr);
 +           token != NULL;
 +           token = strtok_r (NULL, "$", &saveptr))
         {

Thanks,
Pedro Alves