Re: [PATCH v2] gcov: Runtime configurable destination output

[Aaron Conole <aconole at bytheb dot org>]

Ping on this; what are the next steps?

Thanks

Aaron Conole <aconole@bytheb.org> writes:

> The previous gcov behavior was to always output errors on the stderr channel.
> This is fine for most uses, but some programs will require stderr to be
> untouched by libgcov for certain tests. This change allows configuring
> the gcov output via an environment variable which will be used to open
> the appropriate file.
> ---
> v2:
> * Retitled subject
> * Cleaned up whitespace in libgcov-driver-system.c diff
> * Lazy error file opening
> * non-static error file
> * No warnings during compilation
>
>  libgcc/libgcov-driver-system.c | 35 ++++++++++++++++++++++++++++++++++-
>  libgcc/libgcov-driver.c        |  6 ++++++
>  2 files changed, 40 insertions(+), 1 deletion(-)
>
> diff --git a/libgcc/libgcov-driver-system.c b/libgcc/libgcov-driver-system.c
> index 4e3b244..0eb9755 100644
> --- a/libgcc/libgcov-driver-system.c
> +++ b/libgcc/libgcov-driver-system.c
> @@ -23,6 +23,24 @@ a copy of the GCC Runtime Library Exception along with this program;
>  see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
>  <http://www.gnu.org/licenses/>.  */
>  
> +FILE *__gcov_error_file = NULL;
> +
> +static FILE *
> +get_gcov_error_file(void)
> +{
> +  char *gcov_error_filename = getenv("GCOV_ERROR_FILE");
> +  FILE *gcov_error_file = NULL;
> +  if (gcov_error_filename)
> +    {
> +      FILE *openfile = fopen(gcov_error_filename, "a");
> +      if (openfile)
> +        gcov_error_file = openfile;
> +    }
> +  if (!gcov_error_file)
> +    gcov_error_file = stderr;
> +  return gcov_error_file;
> +}
> +
>  /* A utility function for outputing errors.  */
>  
>  static int __attribute__((format(printf, 1, 2)))
> @@ -30,12 +48,27 @@ gcov_error (const char *fmt, ...)
>  {
>    int ret;
>    va_list argp;
> +
> +  if (!__gcov_error_file)
> +    __gcov_error_file = get_gcov_error_file();
> +
>    va_start (argp, fmt);
> -  ret = vfprintf (stderr, fmt, argp);
> +  ret = vfprintf (__gcov_error_file, fmt, argp);
>    va_end (argp);
>    return ret;
>  }
>  
> +#if !IN_GCOV_TOOL
> +static void
> +gcov_error_exit(void)
> +{
> +  if (__gcov_error_file && __gcov_error_file != stderr)
> +    {
> +      fclose(__gcov_error_file);
> +    }
> +}
> +#endif
> +
>  /* Make sure path component of the given FILENAME exists, create
>     missing directories. FILENAME must be writable.
>     Returns zero on success, or -1 if an error occurred.  */
> diff --git a/libgcc/libgcov-driver.c b/libgcc/libgcov-driver.c
> index 9c4eeca..83d84c5c 100644
> --- a/libgcc/libgcov-driver.c
> +++ b/libgcc/libgcov-driver.c
> @@ -46,6 +46,10 @@ void __gcov_init (struct gcov_info *p __attribute__ ((unused))) {}
>  /* A utility function for outputing errors.  */
>  static int gcov_error (const char *, ...);
>  
> +#if !IN_GCOV_TOOL
> +static void gcov_error_exit(void);
> +#endif
> +
>  #include "gcov-io.c"
>  
>  struct gcov_fn_buffer
> @@ -878,6 +882,8 @@ gcov_exit (void)
>      __gcov_root.prev->next = __gcov_root.next;
>    else
>      __gcov_master.root = __gcov_root.next;
> +
> +  gcov_error_exit();
>  }
>  
>  /* Add a new object file onto the bb chain.  Invoked automatically