[Qemu-devel] Re: [PATCH 1/4] Introduce strtosz() library function to convert a string to a byte count.

[Anthony Liguori <anthony@codemonkey.ws>]

On 10/21/2010 10:15 AM, Jes.Sorensen@redhat.com wrote:
> From: Jes Sorensen<Jes.Sorensen@redhat.com>
>
> strtosz() returns -1 on error. It now supports human unit formats in
> eg. 1.0G, with better error handling.
>
> The following suffixes are supported:
> B/b = bytes
> K/k = KB
> M/m = MB
> G/g = GB
> T/t = TB
>
> This patch changes -numa and -m input to use strtosz().
>
> Signed-off-by: Jes Sorensen<Jes.Sorensen@redhat.com>
>    

Applied all.  Thanks.

Regards,

Anthony Liguori

> ---
>   cutils.c      |   88 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>   qemu-common.h |    1 +
>   vl.c          |   31 ++++++-------------
>   3 files changed, 99 insertions(+), 21 deletions(-)
>
> diff --git a/cutils.c b/cutils.c
> index 5883737..28089aa 100644
> --- a/cutils.c
> +++ b/cutils.c
> @@ -23,6 +23,7 @@
>    */
>   #include "qemu-common.h"
>   #include "host-utils.h"
> +#include<math.h>
>
>   void pstrcpy(char *buf, int buf_size, const char *str)
>   {
> @@ -283,3 +284,90 @@ int fcntl_setfl(int fd, int flag)
>   }
>   #endif
>
> +/*
> + * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
> + * M/m for MB, G/g for GB or T/t for TB. Default without any postfix
> + * is MB. End pointer will be returned in *end, if not NULL. A valid
> + * value must be terminated by whitespace, ',' or '\0'. Return -1 on
> + * error.
> + */
> +ssize_t strtosz(const char *nptr, char **end)
> +{
> +    ssize_t retval = -1;
> +    char *endptr, c;
> +    int mul_required = 0;
> +    double val, mul, integral, fraction;
> +
> +    errno = 0;
> +    val = strtod(nptr,&endptr);
> +    if (isnan(val) || endptr == nptr || errno != 0) {
> +        goto fail;
> +    }
> +    integral = modf(val,&fraction);
> +    if (integral != 0) {
> +        mul_required = 1;
> +    }
> +    /*
> +     * Any whitespace character is fine for terminating the number,
> +     * in addition we accept ',' to handle strings where the size is
> +     * part of a multi token argument.
> +     */
> +    c = *endptr;
> +    if (isspace(c) || c == '\0' || c == ',') {
> +        c = 0;
> +    }
> +    switch (c) {
> +    case 'B':
> +    case 'b':
> +        mul = 1;
> +        if (mul_required) {
> +            goto fail;
> +        }
> +        break;
> +    case 'K':
> +    case 'k':
> +        mul = 1<<  10;
> +        break;
> +    case 0:
> +        if (mul_required) {
> +            goto fail;
> +        }
> +    case 'M':
> +    case 'm':
> +        mul = 1ULL<<  20;
> +        break;
> +    case 'G':
> +    case 'g':
> +        mul = 1ULL<<  30;
> +        break;
> +    case 'T':
> +    case 't':
> +        mul = 1ULL<<  40;
> +        break;
> +    default:
> +        goto fail;
> +    }
> +    /*
> +     * If not terminated by whitespace, ',', or \0, increment endptr
> +     * to point to next character, then check that we are terminated
> +     * by an appropriate separating character, ie. whitespace, ',', or
> +     * \0. If not, we are seeing trailing garbage, thus fail.
> +     */
> +    if (c != 0) {
> +        endptr++;
> +        if (!isspace(*endptr)&&  *endptr != ','&&  *endptr != 0) {
> +            goto fail;
> +        }
> +    }
> +    if ((val * mul>= ~(size_t)0) || val<  0) {
> +        goto fail;
> +    }
> +    retval = val * mul;
> +
> +fail:
> +    if (end) {
> +        *end = endptr;
> +    }
> +
> +    return retval;
> +}
> diff --git a/qemu-common.h b/qemu-common.h
> index 81aafa0..0a062d4 100644
> --- a/qemu-common.h
> +++ b/qemu-common.h
> @@ -153,6 +153,7 @@ time_t mktimegm(struct tm *tm);
>   int qemu_fls(int i);
>   int qemu_fdatasync(int fd);
>   int fcntl_setfl(int fd, int flag);
> +ssize_t strtosz(const char *nptr, char **end);
>
>   /* path.c */
>   void init_paths(const char *prefix);
> diff --git a/vl.c b/vl.c
> index df414ef..6043fa2 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -734,16 +734,13 @@ static void numa_add(const char *optarg)
>           if (get_param_value(option, 128, "mem", optarg) == 0) {
>               node_mem[nodenr] = 0;
>           } else {
> -            value = strtoull(option,&endptr, 0);
> -            switch (*endptr) {
> -            case 0: case 'M': case 'm':
> -                value<<= 20;
> -                break;
> -            case 'G': case 'g':
> -                value<<= 30;
> -                break;
> +            ssize_t sval;
> +            sval = strtosz(option, NULL);
> +            if (sval<  0) {
> +                fprintf(stderr, "qemu: invalid numa mem size: %s\n", optarg);
> +                exit(1);
>               }
> -            node_mem[nodenr] = value;
> +            node_mem[nodenr] = sval;
>           }
>           if (get_param_value(option, 128, "cpus", optarg) == 0) {
>               node_cpumask[nodenr] = 0;
> @@ -2163,18 +2160,10 @@ int main(int argc, char **argv, char **envp)
>                   exit(0);
>                   break;
>               case QEMU_OPTION_m: {
> -                uint64_t value;
> -                char *ptr;
> +                ssize_t value;
>
> -                value = strtoul(optarg,&ptr, 10);
> -                switch (*ptr) {
> -                case 0: case 'M': case 'm':
> -                    value<<= 20;
> -                    break;
> -                case 'G': case 'g':
> -                    value<<= 30;
> -                    break;
> -                default:
> +                value = strtosz(optarg, NULL);
> +                if (value<  0) {
>                       fprintf(stderr, "qemu: invalid ram size: %s\n", optarg);
>                       exit(1);
>                   }
>