download.pl: add aria2c support

Use aria2c download tool by default on package download if available in
the system.
aria2c permits to use multiple mirrors and may improve download speed on
special context where servers are hard to reach.

Co-authored-by: Christian Marangi <[email protected]>
Signed-off-by: Bradford Zhang <[email protected]>
[ fix wrong var in the script and improve commit description ]
Signed-off-by: Christian Marangi <[email protected]>

scripts/download.pl

@@ -70,27 +70,52 @@ sub hash_cmd() {
 	return undef;
 }
 
-sub download_cmd($) {
+sub download_cmd {
 	my $url = shift;
 	my $have_curl = 0;
-
-	if (open CURL, "curl --version 2>/dev/null |") {
+	my $have_aria2c = 0;
+	my $filename = shift;
+	my @additional_mirrors = @_;
+	my $mirrors_url = "'$url'";
+
+	my @chArray = ('a'..'z', 'A'..'Z', 0..9);
+	my $rfn = join '', map{ $chArray[int rand @chArray] } 0..9;
+	if (open CURL, '-|', 'curl', '--version') {
 		if (defined(my $line = readline CURL)) {
 			$have_curl = 1 if $line =~ /^curl /;
 		}
 		close CURL;
 	}
+	if (open ARIA2C, '-|', 'aria2c', '--version') {
+		if (defined(my $line = readline ARIA2C)) {
+			$have_aria2c = 1 if $line =~ /^aria2 /;
+		}
+		close ARIA2C;
+	}
 
-	return $have_curl
-		? (qw(curl -f --connect-timeout 20 --retry 5 --location),
+	for my $mirror (@additional_mirrors ) {
+		$mirrors_url = $mirrors_url ." '$mirror /$filename'";
+	}
+
+	if ($have_aria2c) {
+		return join(" ", "touch /dev/shm/${rfn}_spp;",
+			qw(aria2c --stderr -c -x2 -s10 -j10 -k1M), $mirrors_url ,
+			$check_certificate ? () : '--check-certificate=false',
+			"--server-stat-of=/dev/shm/${rfn}_spp",
+			"--server-stat-if=/dev/shm/${rfn}_spp",
+			"-d /dev/shm -o $rfn;",
+			"cat /dev/shm/$rfn;", "rm /dev/shm/$rfn /dev/shm/${rfn}_spp");
+	} elsif ($have_curl) {
+		return (qw(curl -f --connect-timeout 20 --retry 5 --location),
 			$check_certificate ? () : '--insecure',
 			shellwords($ENV{CURL_OPTIONS} || ''),
-			$url)
-		: (qw(wget --tries=5 --timeout=20 --output-document=-),
+			$url);
+	} else {
+		return (qw(wget --tries=5 --timeout=20 --output-document=-),
 			$check_certificate ? () : '--no-check-certificate',
 			shellwords($ENV{WGET_OPTIONS} || ''),
-			$url)
-	;
+			$url);
+	}
 }
 
 my $hash_cmd = hash_cmd();
@@ -100,6 +125,7 @@ sub download
 {
 	my $mirror = shift;
 	my $download_filename = shift;
+	my @additional_mirrors = @_;
 
 	$mirror =~ s!/$!!;
 
@@ -146,9 +172,9 @@ sub download
 			}
 		};
 	} else {
-		my @cmd = download_cmd("$mirror/$download_filename");
+		my @cmd = download_cmd("$mirror/$download_filename", $download_filename, @additional_mirrors);
 		print STDERR "+ ".join(" ",@cmd)."\n";
-		open(FETCH_FD, '-|', @cmd) or die "Cannot launch curl or wget.\n";
+		open(FETCH_FD, '-|', @cmd) or die "Cannot launch aria2c, curl or wget.\n";
 		$hash_cmd and do {
 			open MD5SUM, "| $hash_cmd > '$target/$filename.hash'" or die "Cannot launch $hash_cmd.\n";
 		};
@@ -296,10 +322,11 @@ while (!-f "$target/$filename") {
 	my $mirror = shift @mirrors;
 	$mirror or die "No more mirrors to try - giving up.\n";
 
-	download($mirror, $url_filename);
+	download($mirror, $url_filename, @mirrors);
 	if (!-f "$target/$filename" && $url_filename ne $filename) {
-		download($mirror, $filename);
+		download($mirror, $filename, @mirrors);
 	}
+	@mirrors=();
 }
 
 $SIG{INT} = \&cleanup;