[PATCH] Move {read,write}_all functions to a dedicated header

[Siddhesh Poyarekar]

On 2023-06-01 11:55, Frédéric Bérat wrote:
> Since these functions are used in both catgets/gencat.c and
> malloc/memusage{,stat}.c, it make sense to move them into a dedicated
> header where they can be inlined.
> ---
>   catgets/gencat.c      | 22 +-------------------
>   include/unistd_ext.h  | 48 +++++++++++++++++++++++++++++++++++++++++++
>   malloc/memusage.c     | 25 +---------------------
>   malloc/memusagestat.c | 40 +-----------------------------------
>   4 files changed, 51 insertions(+), 84 deletions(-)
>   create mode 100644 include/unistd_ext.h

This should ideally have been sent in with the rest of the series, 
otherwise it simply breaks pre-commit CI testing:

https://patchwork.sourceware.org/project/glibc/patch/20230601155556.104745-1-fberat@redhat.com/

> 
> diff --git a/catgets/gencat.c b/catgets/gencat.c
> index 826596c2e4..9cacc801b5 100644
> --- a/catgets/gencat.c
> +++ b/catgets/gencat.c
> @@ -37,6 +37,7 @@
>   #include <stdlib.h>
>   #include <string.h>
>   #include <unistd.h>
> +#include <unistd_ext.h>
>   #include <wchar.h>
>   
>   #include "version.h"
> @@ -838,27 +839,6 @@ invalid character: message ignored"));
>     return current;
>   }
>   
> -static void
> -write_all (int fd, const void *buffer, size_t length)
> -{
> -  const char *p = buffer;
> -  const char *end = p + length;
> -  while (p < end)
> -    {
> -      ssize_t ret = write (fd, p, end - p);
> -      if (ret < 0)
> -	error (EXIT_FAILURE, errno,
> -	       gettext ("write of %zu bytes failed after %td: %m"),
> -	       length, p - (const char *) buffer);
> -
> -      if (ret == 0)
> -	error (EXIT_FAILURE, 0,
> -	       gettext ("write returned 0 after writing %td bytes of %zu"),
> -	       p - (const char *) buffer, length);
> -      p += ret;
> -    }
> -}
> -
>   static void
>   write_out (struct catalog *catalog, const char *output_name,
>   	   const char *header_name)
> diff --git a/include/unistd_ext.h b/include/unistd_ext.h
> new file mode 100644
> index 0000000000..b6ce067efb
> --- /dev/null
> +++ b/include/unistd_ext.h

This needs a copyright header.

> @@ -0,0 +1,48 @@
> +#ifndef _UNISTD_EXT_H
> +#define _UNISTD_EXT_H
> +
> +#include <error.h>
> +#include <errno.h>
> +#include <libintl.h>
> +#include <unistd.h>
> +
> +/* Helpers used in catgets/gencat.c and malloc/memusage*.c */
> +static inline void
> +write_all (int fd, const void *buffer, size_t length)
> +{
> +  const char *p = buffer;
> +  const char *end = p + length;
> +  while (p < end)
> +    {
> +      ssize_t ret = write (fd, p, end - p);
> +      if (ret < 0)
> +	error (EXIT_FAILURE, errno,
> +	       gettext ("write of %zu bytes failed after %td: %m"),
> +	       length, p - (const char *) buffer);
> +
> +      if (ret == 0)
> +	error (EXIT_FAILURE, 0,
> +	       gettext ("write returned 0 after writing %td bytes of %zu"),
> +	       p - (const char *) buffer, length);
> +      p += ret;
> +    }
> +}
> +
> +static inline void
> +read_all (int fd, void *buffer, size_t length)
> +{
> +  char *p = buffer;
> +  char *end = p + length;
> +  while (p < end)
> +    {
> +      ssize_t ret = read (fd, p, end - p);
> +      if (ret < 0)
> +	error (EXIT_FAILURE, errno,
> +	       gettext ("read of %zu bytes failed after %td: %m"),
> +	       length, p - (char *) buffer);
> +
> +      p += ret;
> +    }
> +}
> +
> +#endif
> diff --git a/malloc/memusage.c b/malloc/memusage.c
> index 53a3630651..1c6930188c 100644
> --- a/malloc/memusage.c
> +++ b/malloc/memusage.c
> @@ -18,10 +18,7 @@
>   
>   #include <assert.h>
>   #include <dlfcn.h>
> -#include <errno.h>
> -#include <error.h>
>   #include <fcntl.h>
> -#include <libintl.h>

You shouldn't remove these headers because gettext gets used despite the 
unistd_ext.h usage, resulting in an implicit, transitive dependency. 
Does it break anything if you don't remove these includes?

>   #include <stdatomic.h>
>   #include <stdbool.h>
>   #include <stdio.h>
> @@ -30,6 +27,7 @@
>   #include <sys/mman.h>
>   #include <sys/time.h>
>   #include <unistd.h>
> +#include <unistd_ext.h>
>   
>   #include <hp-timing.h>
>   #include <machine-sp.h>
> @@ -145,27 +143,6 @@ peak_atomic_max (_Atomic size_t *peak, size_t val)
>     while (! atomic_compare_exchange_weak (peak, &v, val));
>   }
>   
> -static void
> -write_all (int fd, const void *buffer, size_t length)
> -{
> -  const char *p = buffer;
> -  const char *end = p + length;
> -  while (p < end)
> -    {
> -      ssize_t ret = write (fd, p, end - p);
> -      if (ret < 0)
> -	error (EXIT_FAILURE, errno,
> -	       gettext ("write of %zu bytes failed after %td: %m"),
> -	       length, p - (const char *) buffer);
> -
> -      if (ret == 0)
> -	error (EXIT_FAILURE, 0,
> -	       gettext ("write returned 0 after writing %td bytes of %zu"),
> -	       p - (const char *) buffer, length);
> -      p += ret;
> -    }
> -}
> -
>   /* Update the global data after a successful function call.  */
>   static void
>   update_data (struct header *result, size_t len, size_t old_len)
> diff --git a/malloc/memusagestat.c b/malloc/memusagestat.c
> index cc066d4af9..837b613c2b 100644
> --- a/malloc/memusagestat.c
> +++ b/malloc/memusagestat.c
> @@ -29,6 +29,7 @@
>   #include <stdlib.h>
>   #include <string.h>
>   #include <unistd.h>
> +#include <unistd_ext.h>
>   #include <stdint.h>
>   #include <sys/param.h>
>   #include <sys/stat.h>
> @@ -114,45 +115,6 @@ static int time_based;
>   static int also_total = 0;
>   
>   
> -static void
> -read_all (int fd, void *buffer, size_t length)
> -{
> -  char *p = buffer;
> -  char *end = p + length;
> -  while (p < end)
> -    {
> -      ssize_t ret = read (fd, p, end - p);
> -      if (ret < 0)
> -	error (EXIT_FAILURE, errno,
> -	       gettext ("read of %zu bytes failed after %td: %m"),
> -	       length, p - (char *) buffer);
> -
> -      p += ret;
> -    }
> -}
> -
> -static void
> -write_all (int fd, const void *buffer, size_t length)
> -{
> -  const char *p = buffer;
> -  const char *end = p + length;
> -  while (p < end)
> -    {
> -      ssize_t ret = write (fd, p, end - p);
> -      if (ret < 0)
> -	error (EXIT_FAILURE, errno,
> -	       gettext ("write of %zu bytes failed after %td: %m"),
> -	       length, p - (const char *) buffer);
> -
> -      if (ret == 0)
> -	error (EXIT_FAILURE, 0,
> -	       gettext ("write returned 0 after writing %td bytes of %zu"),
> -	       p - (const char *) buffer, length);
> -      p += ret;
> -    }
> -}
> -
> -
>   int
>   main (int argc, char *argv[])
>   {