[varnishtest] generate the decoding tables

bin/varnishtest/Makefile.am

@@ -76,7 +76,8 @@ EXTRA_DIST = $(top_srcdir)/bin/varnishtest/tests/*.vtc \
 	$(top_srcdir)/bin/varnishtest/tests/README \
 	$(top_srcdir)/bin/varnishtest/gensequences \
 	$(top_srcdir)/bin/varnishtest/sequences \
-	$(top_srcdir)/bin/varnishtest/teken.3
+	$(top_srcdir)/bin/varnishtest/teken.3 \
+	huffman_gen.py
 
 teken.c: teken_state.h
 
@@ -84,4 +85,8 @@ teken_state.h:	$(srcdir)/sequences $(srcdir)/gensequences
 	awk -f $(srcdir)/gensequences $(srcdir)/sequences \
 	    > $(builddir)/teken_state.h
 
+vtc_h2_dectbl.h: huffman_gen.py $(top_srcdir)/include/tbl/vhp_huffman.h
+	$(srcdir)/huffman_gen.py $(top_srcdir)/include/tbl/vhp_huffman.h > $@_
+	mv $@_ $@
+
 CLEANFILES = $(builddir)/teken_state.h

bin/varnishtest/huffman_gen.py

+#!/usr/bin/env python
+
+import re
+import sys
+
+#HPH(0x30, 0x00000000,  5)
+regex = re.compile("^HPH\((.{4}), (.{10}), +(.{1,3})\)")
+
+if len(sys.argv) != 2:
+	print("{} takes one and only one argument".format(sys.argv[0]))
+	sys.exit(2)
+
+class sym:
+	def __init__(self, bigval, bigvall, chr = 0, esc = None):
+		self.vall = bigvall % 8 if bigvall % 8 else 8 
+		self.val = bigval & ((1 << self.vall) - 1)
+		self.pfx = (bigval >> self.vall)# & 0xff
+		self.chr = chr
+		self.esc = esc
+
+tbls = {}
+msl = {} # max sym length
+
+f = open(sys.argv[1])
+for l in f:
+	grp = 1
+	match = regex.match(l)
+	if not match:
+		continue
+
+	chr = int(match.group(grp), 16)
+	grp += 1
+
+	val = int(match.group(grp), 16)
+	grp += 1
+
+	vall = int(match.group(grp))
+
+	s = sym(val, vall, chr)
+	if s.pfx not in tbls:
+		tbls[s.pfx] = {}
+
+	if (s.val in tbls[s.pfx]):
+		assert(tbls[s.pfx][s.val].e)
+	tbls[s.pfx][s.val] = s
+
+	# add the escape entry in the "previous" table
+	if s.pfx:
+		pp = s.pfx >> 8
+		pv = s.pfx & 0xff
+		if pp not in tbls:
+			tbls[pp] = {}
+		tbls[pp][pv] = sym(pv, 8, 0, "&tbl_{:x}".format(s.pfx))
+f.close()
+
+# add the EOS case
+s = sym(63, 6, 0)
+tbls[0xffffff][63] = s
+
+print('''/* NB:  This file is machine generated, DO NOT EDIT!
+ * edit bin/varnishtest/huffman_input instead
+ */
+
+struct stbl;
+
+struct ssym {
+	uint8_t csm;		/* bits consumed */
+	uint8_t	chr;		/* character */
+	struct stbl *nxt;	/* next table */
+};
+
+struct stbl {
+	int msk;
+	struct ssym *syms;
+};
+''')
+
+for pfx in sorted(tbls.keys(), reverse=True):
+	msl = max([ x.vall for x in tbls[pfx].values() ])
+	for s in tbls[pfx].values():
+		s.val = s.val << (msl - s.vall)
+
+	tbl = sorted(tbls[pfx].values(), key= lambda x: x.val)
+	print("\nstatic struct ssym sym_{:x}_array[] = {{".format(pfx))
+	for s in tbl:
+		for j in range(2 ** (msl - s.vall)):
+			print("	{} {{{}, {:3d}, {}}},".format(
+				" "*13 if j else "/* idx {:3d} */".format(s.val + j),
+				s.vall, s.chr % 256,
+				s.esc if s.esc else "NULL"))
+	print('''}};
+
+static struct stbl tbl_{:x} = {{
+	{},
+	sym_{:x}_array
+}};'''.format(pfx, msl, pfx))

bin/varnishtest/vtc_h2_hpack.c

@@ -61,7 +61,7 @@ huff_decode(char *str, int nm, struct hpk_iter *iter, int ilen)
 	int l = 0;
 	uint64_t pack = 0;
 	unsigned pl = 0; /* pack length*/
-	struct stbl *tbl = &byte0;
+	struct stbl *tbl = &tbl_0;
 	struct ssym *sym;
 
 	(void)nm;
@@ -71,7 +71,7 @@ huff_decode(char *str, int nm, struct hpk_iter *iter, int ilen)
 			if (ilen == 0) {
 				if (pl == 0 || (MASK(pack, pl) ==
 						(unsigned)((1U << pl) - 1U))) {
-					assert(tbl == &byte0);
+					assert(tbl == &tbl_0);
 					return (l);
 				}
 			}
@@ -102,7 +102,7 @@ huff_decode(char *str, int nm, struct hpk_iter *iter, int ilen)
 			continue;
 		}
 		str[l++] = sym->chr;
-		tbl = &byte0;
+		tbl = &tbl_0;
 	}
 	return (l);
 }