Re: [Qemu-devel] [PATCH 12/13] vl.c: Remove compile time limit on number of serial ports

[Thomas Huth <thuth@redhat.com>]

On 20.04.2018 16:52, Peter Maydell wrote:
> Instead of having a fixed sized global serial_hds[] array,
> use a local dynamically reallocated one, so we don't have
> a compile time limit on how many serial ports a system has.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  include/sysemu/sysemu.h |  2 --
>  vl.c                    | 15 +++++++--------
>  2 files changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
> index bd5b55c514..989cbc2b7b 100644
> --- a/include/sysemu/sysemu.h
> +++ b/include/sysemu/sysemu.h
> @@ -161,8 +161,6 @@ void hmp_pcie_aer_inject_error(Monitor *mon, const QDict *qdict);
>  
>  #define MAX_SERIAL_PORTS 4
>  
> -extern Chardev *serial_hds[MAX_SERIAL_PORTS];
> -
>  /* Return the Chardev for serial port i, or NULL if none */
>  Chardev *serial_hd(int i);
>  
> diff --git a/vl.c b/vl.c
> index 6daf026da6..a8a98c5a37 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -154,7 +154,8 @@ QEMUClockType rtc_clock;
>  int vga_interface_type = VGA_NONE;
>  static DisplayOptions dpy;
>  int no_frame;
> -Chardev *serial_hds[MAX_SERIAL_PORTS];
> +static int num_serial_hds = 0;
> +static Chardev **serial_hds = NULL;
>  Chardev *parallel_hds[MAX_PARALLEL_PORTS];
>  Chardev *virtcon_hds[MAX_VIRTIO_CONSOLES];
>  Chardev *sclp_hds[MAX_SCLP_CONSOLES];
> @@ -2496,30 +2497,28 @@ static int foreach_device_config(int type, int (*func)(const char *cmdline))
>  
>  static int serial_parse(const char *devname)
>  {
> -    static int index = 0;
> +    int index = num_serial_hds;
>      char label[32];
>  
>      if (strcmp(devname, "none") == 0)
>          return 0;
> -    if (index == MAX_SERIAL_PORTS) {
> -        error_report("too many serial ports");
> -        exit(1);
> -    }
>      snprintf(label, sizeof(label), "serial%d", index);
> +    serial_hds = g_renew(Chardev *, serial_hds, index + 1);
> +
>      serial_hds[index] = qemu_chr_new(label, devname);
>      if (!serial_hds[index]) {

In case you respin: I think you could do this without the index variable
and just use num_serial_hds directly instead (just a matter of taste,
though).

Reviewed-by: Thomas Huth <thuth@redhat.com>