FU::Util: Add brotli_compress() and use it for FU output compression

Seems to compresses and perform better than libdeflate at level 6, so
certainly worth using.

FU.pm

@@ -400,7 +400,7 @@ sub _do_req($c) {
             ($REQ->{trace_sqlexec}||0)*1000, ($REQ->{trace_sqlprep}||0)*1000,
             $REQ->{trace_nsqldirect}||0, $REQ->{trace_nsqlprep}||0, $REQ->{trace_nsql} : '',
         $REQ->{status}, ($REQ->{reshdr}{'content-type'}//'-') =~ s/;.+$//r,
-        length($REQ->{resbody}), substr($REQ->{reshdr}{'content-encoding'}//'bytes', 0, 1)
+        length($REQ->{resbody}), substr($REQ->{reshdr}{'content-encoding'}//'r', 0, 1)
     ) if FU::debug || $proc_ms > (FU::log_slow_reqs||1e10);
 }
 
@@ -850,6 +850,8 @@ sub _error_page($, $code, $title, $msg) {
 }
 
 sub _finalize {
+    state $hasgzip = FU::Util::gzip_lib();
+    state $hasbrotli = eval { FU::Util::brotli_compress(6, ''); 1 };
     my $r = $FU::REQ;
 
     fu->add_header('set-cookie', $_) for $r->{rescookie} ? sort values $r->{rescookie}->%* : ();
@@ -861,13 +863,19 @@ sub _finalize {
         $r->{resbody} = '';
 
     } else {
-        if (FU::Util::gzip_lib() && length($r->{resbody}) > 256
+        if (($hasgzip || $hasbrotli) && length($r->{resbody}) > 256
-                && !defined $r->{reshdr}{'content-encoding'} && FU::compress_mimes->{$r->{reshdr}{'content-type'}}) {
+                && !defined $r->{reshdr}{'content-encoding'}
+                && FU::compress_mimes->{$r->{reshdr}{'content-type'}}
+        ) {
 
             $r->{reshdr}{'vary'} = ($r->{reshdr}{'vary'} ? $r->{reshdr}{'vary'}.', ' : '').'accept-encoding'
                 if ($r->{reshdr}{'vary'}||'') !~ /accept-encoding/i;
 
-            if (($r->{hdr}{'accept-encoding'}||'') =~ /gzip/) {
+            if ($hasbrotli && ($r->{hdr}{'accept-encoding'}||'') =~ /\bbr\b/) {
+                $r->{resbody} = FU::Util::brotli_compress(6, $r->{resbody});
+                $r->{reshdr}{'content-encoding'} = 'br';
+
+            } elsif ($hasgzip && ($r->{hdr}{'accept-encoding'}||'') =~ /\bgzip\b/) {
                 $r->{resbody} = FU::Util::gzip_compress(6, $r->{resbody});
                 $r->{reshdr}{'content-encoding'} = 'gzip';
             }
@@ -991,6 +999,9 @@ C<dlopen()>.
 =item * C<libdeflate.so> or C<libz-ng.so> or C<libz.so> - required for
 C<gzip_compress()> in L<FU::Util> and used for HTTP output compression.
 
+=item * C<libbrotlienc.so> - required for C<brotli_compress()> in L<FU::Util>
+and used for HTTP output compression.
+
 =back
 
 

FU.xs

@@ -126,6 +126,10 @@ void gzip_compress(IV level, SV *in)
   CODE:
     ST(0) = fugz_compress(aTHX_ level, in);
 
+void brotli_compress(IV level, SV *in)
+  CODE:
+    ST(0) = fubr_compress(aTHX_ level, in);
+
 void fdpass_send(int socket, int fd, SV *data)
   CODE:
     STRLEN buflen;

FU/Util.pm

@@ -13,7 +13,7 @@ our @EXPORT_OK = qw/
     utf8_decode uri_escape uri_unescape
     query_decode query_encode
     httpdate_format httpdate_parse
-    gzip_lib gzip_compress
+    gzip_lib gzip_compress brotli_compress
     fdpass_send fdpass_recv
 /;
 
@@ -401,6 +401,8 @@ I<zlib(-ng)> the level is capped at 9. 6 is typically used as a default.
 
 Throws an error if no suitable library was found.
 
+This function is B<NOT> safe to use from multiple threads!
+
 =back
 
 This module does not currently implement decompression. If you need that, or
@@ -409,6 +411,22 @@ L<Compress::Raw::Zlib> and L<Compress::Zlib> in the core Perl distribution and
 L<Gzip::Deflate> on CPAN.
 
 
+=head2 Brotli Compression
+
+Just a small wrapper around C<libbrotlienc.so>'s one-shot compression
+interface.
+
+=over
+
+=item brotli_compress($level, $data)
+
+Returns a byte string with the brotli-compressed version of C<$data> at the
+given quality C<$level> (between 0 and 11).
+
+Throws an error if C<libbrotlienc.so> could not be found or loaded.
+
+=back
+
 
 =head2 File Descriptor Passing
 

c/compress.c

@@ -124,5 +124,38 @@ static SV *fugz_compress(pTHX_ IV level, SV *in) {
 
     if (fugz_imp == 1) return fugz_compress_ld(aTHX_ level, bytes, inlen);
     else return fugz_compress_zlib(aTHX_ level, bytes, inlen);
-    return &PL_sv_undef;
+}
+
+
+
+/* Brotli */
+
+typedef enum { BROTLI_MODE_GENERIC = 0, BROTLI_MODE_TEXT = 1, BROTLI_MODE_FONT = 2 } BrotliEncoderMode;
+
+static size_t (*BrotliEncoderMaxCompressedSize)(size_t);
+static int (*BrotliEncoderCompress)(int, int, BrotliEncoderMode, size_t, const char *, size_t *, char *);
+
+static SV *fubr_compress(pTHX_ IV level, SV *in) {
+    if (!BrotliEncoderCompress) {
+        void *handle;
+        if (!(handle = dlopen("libbrotlienc.so", RTLD_LAZY))
+         || !(BrotliEncoderMaxCompressedSize = dlsym(handle, "BrotliEncoderMaxCompressedSize"))
+         || !(BrotliEncoderCompress = dlsym(handle, "BrotliEncoderCompress")))
+            fu_confess("Unable to load libbrotlienc.so: %s", dlerror());
+    }
+    if (level < 0 || level > 11) fu_confess("Invalid compression level: %"IVdf, level);
+
+    STRLEN inlen;
+    const char *bytes = SvPVbyte(in, inlen);
+
+    size_t outlen = BrotliEncoderMaxCompressedSize(inlen);
+    /* "Result is only valid if quality is at least 2", so let's use a (more conservative?) fallback */
+    if (level < 2 && outlen < inlen + 256) outlen = inlen + 256;
+
+    SV *out = sv_2mortal(newSV(outlen));
+    SvPOK_only(out);
+    if (!BrotliEncoderCompress(level, 22, BROTLI_MODE_GENERIC, inlen, bytes, &outlen, SvPVX(out)))
+        fu_confess("Brotli compression failed");
+    SvCUR_set(out, outlen);
+    return out;
 }

t/compress.t

@@ -1,18 +1,34 @@
 use v5.36;
 use Test::More;
-use FU::Util qw/gzip_lib gzip_compress/;
+use FU::Util qw/gzip_lib gzip_compress brotli_compress/;
 
 like gzip_lib, qr/^(|libdeflate|zlib-ng|zlib)$/, gzip_lib;
 
-plan skip_all => 'No suitable gzip library found' if !gzip_lib;
+my $incompressible;
-plan skip_all => 'Compress::Zlib not found' if !eval { require Compress::Zlib };
 
-my $incompressible = Compress::Zlib::memGzip(join '', map chr(rand 256), 0..93123);
+subtest 'gzip_compress', sub {
+    plan skip_all => 'No suitable gzip library found' if !gzip_lib;
+    plan skip_all => 'Compress::Zlib not found' if !eval { require Compress::Zlib };
 
-for my $str ('', 'Hello world!', 'x'x4096, $incompressible) {
+    $incompressible = Compress::Zlib::memGzip(join '', map chr(rand 256), 0..93123);
+
+    for my $str ('', 'Hello world!', 'x'x4096, $incompressible) {
         is Compress::Zlib::memGunzip(gzip_compress(0, $str)), $str;
         is Compress::Zlib::memGunzip(gzip_compress(12, $str)), $str;
-}
+    }
+};
+
+
+subtest 'brotli_compress', sub {
+    plan skip_all => 'libbrotlienc not available'
+        if !eval { brotli_compress 6, '' } && $@ =~ /Unable to load/;
+
+    ok length(brotli_compress 0, '') > 0;
+    ok length(brotli_compress 11, '') > 0;
+    # '0' does not disable compression...
+    ok length(brotli_compress 0, 'Hello world!'x100) < 200;
+    ok length(brotli_compress 11, 'Hello world!'x100) < 100;
+};
 
 
 done_testing;
@@ -29,6 +45,8 @@ for (0..1000) {
         local $_ = gzip_lib;
         $_ = gzip_compress(0, $str);
         $_ = gzip_compress(12, $str);
+        $_ = brotli_compress(0, $str);
+        $_ = brotli_compress(11, $str);
     }
 }
 diag count_sv;
@@ -44,4 +62,5 @@ my $data = <$F>;
 cmpthese -3, {
     memGzip => 'Compress::Zlib::memGzip($data)',
     gzip_compress => 'gzip_compress(6, $data)',
+    brotli_compress => 'brotli_compress(6, $data)',
 };