Re: [PATCH v8 2/6] util: Introduce read_file() and read_file_integer() function

[David Gibson <david@gibson.dropbear.id.au>]

[-- Attachment #1: Type: text/plain, Size: 2817 bytes --]

On Fri, Nov 14, 2025 at 09:58:57AM +0800, Yumei Huang wrote:
> On Fri, Nov 14, 2025 at 8:01 AM Stefano Brivio <sbrivio@redhat.com> wrote:
> >
> > On Mon, 10 Nov 2025 17:31:33 +0800
> > Yumei Huang <yuhuang@redhat.com> wrote:
> >
> > > Signed-off-by: Yumei Huang <yuhuang@redhat.com>
> > > Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> > > ---
> > >  util.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> > >  util.h |  2 ++
> > >  2 files changed, 88 insertions(+)
> > >
> > > diff --git a/util.c b/util.c
> > > index 44c21a3..c4c849c 100644
> > > --- a/util.c
> > > +++ b/util.c
> > > @@ -590,6 +590,92 @@ int write_file(const char *path, const char *buf)
> > >       return len == 0 ? 0 : -1;
> > >  }
> > >
> > > +/**
> > > + * read_file() - Read contents of file into a NULL-terminated buffer
> > > + * @path:    Path to file to read
> > > + * @buf:     Buffer to store file contents
> > > + * @buf_size:        Size of buffer
> > > + *
> > > + * Return: number of bytes read on success, -1 on error, -ENOBUFS on truncation
> > > + */
> > > +ssize_t read_file(const char *path, char *buf, size_t buf_size)
> > > +{
> > > +     int fd = open(path, O_RDONLY | O_CLOEXEC);
> > > +     size_t total_read = 0;
> > > +     ssize_t rc;
> > > +
> > > +     if (fd < 0) {
> > > +             warn_perror("Could not open %s", path);
> > > +             return -1;
> > > +     }
> > > +
> > > +     while (total_read < buf_size) {
> > > +             rc = read(fd, buf + total_read, buf_size - total_read);
> >
> > cppcheck rightfully says that:
> >
> > util.c:604:10: style: The scope of the variable 'rc' can be reduced. [variableScope]
> >  ssize_t rc;
> >          ^
> 
> Right.
> Seems it also says:
> 
> tcp.c:2814:0: style: The function 'tcp_get_rto_params' should have
> static linkage since it is not used outside of its translation unit.
> [staticFunction]
> void tcp_get_rto_params(struct ctx *c)
> ^

Ah, yes, that should be 'static'.  Sorry, missed that in earlier reviews.

> util.c:601:0: style: The function 'read_file' should have static
> linkage since it is not used outside of its translation unit.
> [staticFunction]
> ssize_t read_file(const char *path, char *buf, size_t buf_size)
> 
> I understand read_file() may be called from other places in the
> future. But do we need to add static now? I guess we need it for
> tcp_get_rto_params().

It's true that read_file() might be used elsewhere in future.  I'd
still make it 'static' for now, and we can change that if/when we use
it somewhere else.

-- 
David Gibson (he or they)	| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you, not the other way
				| around.
http://www.ozlabs.org/~dgibson

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]