commit bb4b8acc26034791cb60bddf66924babb22e4522
from: Kyle Nusbaum <kyle@datadog.com>
via: Dan Cross <crossd@gmail.com>
date: Tue Jul 26 16:06:12 2022 UTC

src/cmd/fontsrv: pad subfile names to support correct file length

For fonts with subfiles that go beyond the xffff range, the font file size
calculation is incorrect, since lines beyond that range have additional
characters. This patch pads all of the ranges and subfont names with
leading zeros in order to keep them all lines the same length and fixes the
font file length calculation.

commit - 686f5d035cc111a6a18d918ef60929f24b0cb424
commit + bb4b8acc26034791cb60bddf66924babb22e4522
blob - b2189be98fbe3f33ecf24f6ad4eba56a9cd406f0
blob + 54cd52a8b7ef5b6a556a23b7c066a6ae2c46c9b9
--- src/cmd/fontsrv/main.c
+++ src/cmd/fontsrv/main.c
@@ -102,12 +102,12 @@ dostat(vlong path, Qid *qid, Dir *dir)
 	case Qfontfile:
 		f = &xfont[QFONT(path)];
 		load(f);
-		length = 11+1+11+1+f->nfile*(6+1+6+1+9+1);
+		length = 11+1+11+1+f->nfile*(8+1+8+1+11+1);
 		name = "font";
 		break;
 
 	case Qsubfontfile:
-		snprint(buf, sizeof buf, "x%04x.bit", (int)QRANGE(path)*SubfontSize);
+		snprint(buf, sizeof buf, "x%06x.bit", (int)QRANGE(path)*SubfontSize);
 		name = buf;
 		break;
 	}
@@ -189,7 +189,7 @@ xwalk1(Fid *fid, char *name, Qid *qid)
 			goto NotFound;
 		p++;
 		n = strtoul(p, &p, 16);
-		if(p < name+5 || p > name+5 && name[1] == '0' || n%SubfontSize != 0 || n/SubfontSize >= MaxSubfont || strcmp(p, ".bit") != 0 || !f->range[n/SubfontSize])
+		if(p < name+7 || p > name+7 && name[1] == '0' || n%SubfontSize != 0 || n/SubfontSize >= MaxSubfont || strcmp(p, ".bit") != 0 || !f->range[n/SubfontSize])
 			goto NotFound;
 		path += Qsubfontfile - Qsizedir + qpath(0, 0, 0, 0, n/SubfontSize);
 		break;
@@ -320,7 +320,7 @@ xread(Req *r)
 				f->loadheight(f, QSIZE(path), &height, &ascent);
 			fmtprint(&fmt, "%11d %11d\n", height, ascent);
 			for(i=0; i<f->nfile; i++)
-				fmtprint(&fmt, "0x%04x 0x%04x x%04x.bit\n", f->file[i]*SubfontSize, ((f->file[i]+1)*SubfontSize) - 1, f->file[i]*SubfontSize);
+				fmtprint(&fmt, "0x%06x 0x%06x x%06x.bit\n", f->file[i]*SubfontSize, ((f->file[i]+1)*SubfontSize) - 1, f->file[i]*SubfontSize);
 			f->fonttext = fmtstrflush(&fmt);
 			f->nfonttext = strlen(f->fonttext);
 		}