From d391236269314a759acb7dfb7ec01ccaa0e0b32c Mon Sep 17 00:00:00 2001
From: Bradford Zhang <zyc@zyc.name>
Date: Wed, 14 Sep 2022 07:54:04 +0800
Subject: [PATCH] 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 <ansuelsmth@gmail.com>
Signed-off-by: Bradford Zhang <zyc@zyc.name>
[ fix wrong var in the script and improve commit description ]
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 scripts/download.pl | 53 ++++++++++++++++++++++++++++++++++-----------
 1 file changed, 40 insertions(+), 13 deletions(-)

diff --git a/scripts/download.pl b/scripts/download.pl
index 33e1e12c1ea..4dec985fd1a 100755
--- a/scripts/download.pl
+++ b/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;
-- 
2.30.2