[pacman-dev] [PATCH] Add a fetch callback to allow front-end download support

[Sebastian Nowicki]

On 29/03/2009, at 5:34 AM, Dan McGee wrote:

> On Fri, Feb 20, 2009 at 2:31 AM, Sebastian Nowicki  
> <sebnow at gmail.com> wrote:
>> This allows a frontend to define its own download algorithm so that  
>> the
>> libfetch dependency can be omitted without using an external  
>> process.  The
>> callback will be used if it is defined, otherwise the internal method
>> (libfetch) is used, if available.
>>
>> The external download method was moved to pacman and is set as the  
>> fetch
>> callback, if the command is defined in the configuration file. As a  
>> result,
>> alpm_option_get_xfercommand() and alpm_option_set_xfercommand()  
>> have been
>> removed.
>>
>> Signed-off-by: Sebastian Nowicki <sebnow at gmail.com>
>
> cc1: warnings being treated as errors
> dload.c: In function ‘download’:
> dload.c:274: error: passing argument 4 of ‘handle->fetchcb’ makes
> pointer from integer without a cast
> (you used mtimeold twice)
>
> handle.c: In function ‘_alpm_handle_free’:
> handle.c:81: error: ‘pmhandle_t’ has no member named ‘xfercommand’
> handle.c:81: error: ‘pmhandle_t’ has no member named ‘xfercommand’
> (just kill the line)
>
> In file included from pacman.c:52:
> conf.h:26:1: error: "PATH_MAX" redefined
> In file included from /usr/include/bits/local_lim.h:39,
>                 from /usr/include/bits/posix1_lim.h:153,
>                 from /usr/include/limits.h:145,
>                 from
> /usr/lib/gcc/x86_64-unknown-linux-gnu/4.3.3/include-fixed/limits.h: 
> 122,
>                 from
> /usr/lib/gcc/x86_64-unknown-linux-gnu/4.3.3/include-fixed/ 
> syslimits.h:7,
>                 from
> /usr/lib/gcc/x86_64-unknown-linux-gnu/4.3.3/include-fixed/limits.h:11,
>                 from pacman.c:30:
> /usr/include/linux/limits.h:12:1: error: this is the location of the
> previous definition
>
> Don't mess with that path_max #ifdef junk- although it does look like
> we interchange <sys/syslimits.h> and <limits.h> to get the definition
> of PATH_MAX. Which one is correct?
>
> Do you guys compile these patches first? :P

I compiled it and tested. I must have not compiled with --enable-debug  
or something. Perhaps my last change broke it (I might have forgotten  
to test, oops), which is more likely. Sorry either way.

> I'm assuming the below code didn't really change from what was in the
> backend- can you verify this, or point out what you did modify?

For the most part, yes. I did "inline" some functions, which were  
static. There might have been other minor changes.

Quickly looking over the log, I changed this:

>        filename = get_filename(url);
>        if(!filename) {
>                RET_ERR(PM_ERR_EXTERNAL_DOWNLOAD, -1);
>        }
>        destfile = get_destfile(localpath, filename);
>        tempfile = get_tempfile(localpath, filename);


To this:

>        filename = strrchr(url, '/');
>        if(!filename) {
>                return -1;
>        } else {
>                filename++; /* omit leading slash */
>        }
>
>        len = strlen(localpath) + strlen(filename) + 1;
>        destfile = calloc(len, sizeof(*destfile));
>        snprintf(destfile, len, "%s%s", localpath, filename);
>
>        len += 5; /* ".part" */
>        tempfile = calloc(len, sizeof(*tempfile));
>        snprintf(tempfile, len, "%s.part", destfile);


I'll fix the patch up tomorrow.