[pacman-dev] [PATCH] libalpm: fix alpm_fetch_pkgurl with a fetch callback

[Guillaume Benoit]

Le 01/05/2021 à 05:53, Andrew Gregory a écrit :
> On 04/30/21 at 12:09pm, Guillaume Benoit wrote:
>> After download, alpm_fetch_pkgurl uses payload->destfile_name
>> and payload->tempfile_name in order to find the downloaded file path.
>> Those fields are not set if a custom fetch callback is defined.
>> Use filecache_find_url instead, like in the beginning of the function.
>>
>> ---
>>   lib/libalpm/dload.c | 13 ++++---------
>>   1 file changed, 4 insertions(+), 9 deletions(-)
>>
>> diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c
>> index 6f33451a..d45c7707 100644
>> --- a/lib/libalpm/dload.c
>> +++ b/lib/libalpm/dload.c
>> @@ -1007,16 +1007,11 @@ int SYMEXPORT alpm_fetch_pkgurl(alpm_handle_t *handle, const alpm_list_t *urls,
>>   			EVENT(handle, &event);
>>   		}
>>   -		for(i = payloads; i; i = i->next) {
>> -			struct dload_payload *payload = i->data;
>> -			char *filepath;
>> +		for(i = urls; i; i = i->next) {
>> +			char *url = i->data;
>>   -			if(payload->destfile_name) {
>> -				const char *filename = mbasename(payload->destfile_name);
>> -				filepath = _alpm_filecache_find(handle, filename);
>> -			} else {
>> -				STRDUP(filepath, payload->tempfile_name, GOTO_ERR(handle, ALPM_ERR_MEMORY, err));
>> -			}
>> +			/* attempt again to find the file in our pkgcache */
>> +			char *filepath = filecache_find_url(handle, url);
>>   			if(filepath) {
>>   				alpm_list_append(fetched, filepath);
>>   			} else {
> 
> Without testing since this needs to be rebased now; this looks broken.
> filecache_find_url with fail for any url where destfile_name doesn't
> match the file name in the url.  Notably, that includes the download
> links on Arch's package pages:
> https://archlinux.org/packages/core/x86_64/pacman/download/
> 
Yes, with or without this patch, the current implementation doesn't work for this kind of url when using a fetch callback.
The solution I see is to change the fetch callback signature by making it return the path of the downloaded file.
Otherwise this patch works for standard mirror urls.