[pacman-dev] [PATCH] download: major refactor to address lingering issues

[Xavier]

On Thu, Nov 12, 2009 at 9:09 AM, Dan McGee <dan at archlinux.org> wrote:
> +       _alpm_log(PM_LOG_DEBUG, "ust.size: %ld local_size: %ld compare: %ld\n",
> +                       ust.size, local_size, local_size - ust.size);
>
> +       } else if(fileurl->offset) {
> +               _alpm_log(PM_LOG_DEBUG, "resuming download at position %ld\n", fileurl->offset);
>        }

This does not compile here :
dload.c:190: error: format '%ld' expects type 'long int', but argument
3 has type 'off_t'
dload.c:190: error: format '%ld' expects type 'long int', but argument
4 has type 'off_t'
dload.c:190: error: format '%ld' expects type 'long int', but argument
5 has type 'off_t'
dload.c:223: error: format '%ld' expects type 'long int', but argument
3 has type 'off_t'

I am always confused about this stuff, so I looked at one older patch :
http://code.toofishes.net/cgit/dan/pacman.git/commit/?id=0669c9bfac7aead01f1400444e691d542f7645c2&ss=1
But this was confusing too. It looks like the same patch used three
different ways to print off_t :
1 - %jd and cast to intmax_t
2 - %ju and cast to intmax_t
3 - %lld and cast to long long

After looking at man types.h and man printf, it seems off_t is a
signed integer, like intmax_t
So 1 seems alright
but maybe 3 is alright too ?

googling a bit leads to a lot of different and confusing answers.
But it seems the most correct and portable way is to use a macro for
the printf format : %" PRId64 "
http://mail-index.netbsd.org/tech-misc/2003/01/20/0002.html
http://stackoverflow.com/questions/586928/how-should-i-print-types-like-offt-and-sizet

It looks like PRId64 is defined in #include <inttypes.h>
But dload.c does not have this include and it still works. Maybe it's
included by another header ? How do I find out ?
Should we add #include <inttypes.h> anyway ?

diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c
index 683f514..05555f2 100644
--- a/lib/libalpm/dload.c
+++ b/lib/libalpm/dload.c
@@ -186,7 +186,7 @@ static int download_internal(const char *url,
const char *localpath,

 	_alpm_log(PM_LOG_DEBUG, "ust.mtime: %ld local_time: %ld compare: %ld\n",
 			ust.mtime, local_time, local_time - ust.mtime);
-	_alpm_log(PM_LOG_DEBUG, "ust.size: %ld local_size: %ld compare: %ld\n",
+	_alpm_log(PM_LOG_DEBUG, "ust.size: %"PRId64" local_size: %"PRId64"
compare: %"PRId64"\n",
 			ust.size, local_size, local_size - ust.size);
 	if(!force && ust.mtime && ust.mtime == local_time
 			&& ust.size && ust.size == local_size) {
@@ -220,7 +220,7 @@ static int download_internal(const char *url,
const char *localpath,
 		fclose(localf);
 		localf = NULL;
 	} else if(fileurl->offset) {
-		_alpm_log(PM_LOG_DEBUG, "resuming download at position %ld\n",
fileurl->offset);
+		_alpm_log(PM_LOG_DEBUG, "resuming download at position
%"PRId64"\n", fileurl->offset);
 	}