[kvm-unit-tests PATCH v2 1/2] lib: Add STR_IS_Y and STR_IS_N for checking env vars

[Andrew Jones]

On Tue, Jul 08, 2025 at 08:48:10AM -0700, Jesse Taube wrote:
> the line:
> (s && (*s == '1' || *s == 'y' || *s == 'Y'))
> is used in a few places add a macro for it and it's 'n' counterpart.
                                                 ^ its
> 
> Add GET_CONFIG_OR_ENV for CONFIG values which can be overridden by
> the environment.
> 
> Signed-off-by: Jesse Taube <jesse at rivosinc.com>
> ---
>  lib/argv.h        | 13 +++++++++++++
>  lib/errata.h      |  7 ++++---
>  riscv/sbi-tests.h |  3 ++-
>  3 files changed, 19 insertions(+), 4 deletions(-)
> 
> diff --git a/lib/argv.h b/lib/argv.h
> index 0fa77725..ecbb40d7 100644
> --- a/lib/argv.h
> +++ b/lib/argv.h
> @@ -14,4 +14,17 @@ extern void setup_args_progname(const char *args);
>  extern void setup_env(char *env, int size);
>  extern void add_setup_arg(const char *arg);
>  
> +#define STR_IS_Y(s) (s && (*s == '1' || *s == 'y' || *s == 'Y'))
> +#define STR_IS_N(s) (s && (*s == '0' || *s == 'n' || *s == 'N'))
> +
> +/*
> + * Get the boolean value of CONFIG_{name}
> + * which can be overridden by the {name}
> + * variable in the environment if present.
> + */
> +#define GET_CONFIG_OR_ENV(name) ({		\
> +	const char *s = getenv(#name);		\
> +	s ? STR_IS_Y(s) : CONFIG_##name;	\
> +})

This requires CONFIG_##name to be defined, even if it's a 'no'. That's
probably OK, but a solution that allows it to be undefined, which then
means 'no' would be nice.

> +
>  #endif
> diff --git a/lib/errata.h b/lib/errata.h
> index de8205d8..78007243 100644
> --- a/lib/errata.h
> +++ b/lib/errata.h
> @@ -7,6 +7,7 @@
>  #ifndef _ERRATA_H_
>  #define _ERRATA_H_
>  #include <libcflat.h>
> +#include <argv.h>
>  
>  #include "config.h"
>  
> @@ -28,7 +29,7 @@ static inline bool errata_force(void)
>  		return true;
>  
>  	s = getenv("ERRATA_FORCE");
> -	return s && (*s == '1' || *s == 'y' || *s == 'Y');
> +	return STR_IS_Y(s);
>  }
>  
>  static inline bool errata(const char *erratum)
> @@ -40,7 +41,7 @@ static inline bool errata(const char *erratum)
>  
>  	s = getenv(erratum);
>  
> -	return s && (*s == '1' || *s == 'y' || *s == 'Y');
> +	return STR_IS_Y(s);
>  }
>  
>  static inline bool errata_relaxed(const char *erratum)
> @@ -52,7 +53,7 @@ static inline bool errata_relaxed(const char *erratum)
>  
>  	s = getenv(erratum);
>  
> -	return !(s && (*s == '0' || *s == 'n' || *s == 'N'));
> +	return !STR_IS_N(s);
>  }
>  
>  #endif
> diff --git a/riscv/sbi-tests.h b/riscv/sbi-tests.h
> index c1ebf016..4e051dca 100644
> --- a/riscv/sbi-tests.h
> +++ b/riscv/sbi-tests.h
> @@ -37,6 +37,7 @@
>  
>  #ifndef __ASSEMBLER__
>  #include <libcflat.h>
> +#include <argv.h>
>  #include <asm/sbi.h>
>  
>  #define __sbiret_report(kfail, ret, expected_error, expected_value,						\
> @@ -94,7 +95,7 @@ static inline bool env_enabled(const char *env)
>  {
>  	char *s = getenv(env);
>  
> -	return s && (*s == '1' || *s == 'y' || *s == 'Y');
> +	return STR_IS_Y(s);
>  }
>  
>  void split_phys_addr(phys_addr_t paddr, unsigned long *hi, unsigned long *lo);
> -- 
> 2.43.0
>

Besides the typo, LGTM

Reviewed-by: Andrew Jones <andrew.jones at linux.dev>