ref: da7d6df6faf18e289fe0f3f61524dcc7fddeef18
dir: /appl/svc/webget/wgutils.b/
implement WebgetUtils;
include "sys.m";
sys: Sys;
include "draw.m";
include "string.m";
include "bufio.m";
include "dial.m";
include "imagefile.m";
readgif, readjpg, readxbitmap: RImagefile;
include "image2enc.m";
image2enc: Image2enc;
include "message.m";
include "url.m";
include "wgutils.m";
Iobuf: import B;
include "strinttab.m";
T: StringIntTab;
Msg, Nameval: import M;
ParsedUrl: import U;
logfd: ref Sys->FD;
# return from acceptmatch; and conv arg to readbody
BadConv, NoConv, Gif2xcompressed, Jpeg2xcompressed, Xbm2xcompressed: con iota;
# Both extensions and Content-Types can be in same table.
# This array should be kept sorted
mtypes := array[] of { T->StringInt
("ai", ApplPostscript),
("application/html", TextHtml),
("application/pdf", ApplPdf),
("application/postscript", ApplPostscript),
("application/rtf", ApplRtf),
("application/soap+xml", TextPlain),
("application/x-html", TextHtml),
("au", AudioBasic),
("audio/au", AudioBasic),
("audio/basic", AudioBasic),
("bit", ImageXCompressed),
("bit2", ImageXCompressed2),
("eps", ApplPostscript),
("gif", ImageGif),
("htm", TextHtml),
("html", TextHtml),
("image/gif", ImageGif),
("image/ief", ImageIef),
("image/jpeg", ImageJpeg),
("image/tiff", ImageTiff),
("image/x-compressed", ImageXCompressed),
("image/x-compressed2", ImageXCompressed2),
("image/x-xbitmap", ImageXXBitmap),
("jpe", ImageJpeg),
("jpeg", ImageJpeg),
("jpg", ImageJpeg),
("pdf", ApplPdf),
("ps", ApplPostscript),
("text", TextPlain),
("text/html", TextHtml),
("text/plain", TextPlain),
("text/x-html", TextHtml),
("text/xml", TextXml),
("tif", ImageTiff),
("tiff", ImageTiff),
("txt", TextPlain),
("video/mpeg", VideoMpeg),
("video/quicktime", VideoQuicktime),
};
# following array must track media type def in wgutils.m
mnames := array[] of {
"application/x-unknown",
"text/plain",
"text/html",
"application/postscript",
"application/rtf",
"application/pdf",
"image/jpeg",
"image/gif",
"image/ief",
"image/tiff",
"image/x-compressed",
"image/x-compressed2",
"image/x-xbitmap",
"audio/basic",
"video/mpeg",
"video/quicktime",
"application/soap+xml",
"text/xml"
};
init(m: Message, s: String, b: Bufio, u: Url, di: Dial, lfd: ref Sys->FD)
{
sys = load Sys Sys->PATH;
M = m;
S = s;
B = b;
U = u;
DI = di;
logfd = lfd;
T = load StringIntTab StringIntTab->PATH;
readgif = load RImagefile RImagefile->READGIFPATH;
readjpg = load RImagefile RImagefile->READJPGPATH;
readxbitmap = load RImagefile RImagefile->READXBMPATH;
image2enc = load Image2enc Image2enc->PATH;
if(T == nil || readgif == nil || readjpg == nil || readxbitmap == nil || image2enc == nil) {
sys->fprint(sys->fildes(2), "webget: failed to load T, readgif, readjpg, readxbitmap, or imageremap: %r\n");
return;
}
readgif->init(B);
readjpg->init(B);
readxbitmap->init(B);
}
# Return msg with error provoked by bad user action
usererr(r: ref Req, msg: string) : ref Msg
{
m := Msg.newmsg();
m.prefixline = sys->sprint("ERROR %s %s\n", r.reqid, msg);
m.bodylen = 0;
return m;
}
okprefix(r: ref Req, mrep: ref Msg)
{
(nil, sctype) := mrep.fieldval("content-type");
if(sctype == "")
sctype = "text/html";
else
sctype = canon_mtype(sctype);
(nil, cloc) := mrep.fieldval("content-location");
if(cloc == "")
cloc = "unknown";
mrep.prefixline = "OK " + string mrep.bodylen + " " + r.reqid + " " + sctype + " " + cloc +"\n";
}
canon_mtype(s: string) : string
{
# lowercase, and remove possible parameter
ls := S->tolower(s);
(ts, nil) := S->splitl(ls, "; ");
return ts;
}
mediatype(s: string, dflt: int) : int
{
(fnd, val) := T->lookup(mtypes, canon_mtype(s));
if(!fnd)
val = dflt;
return val;
}
acceptmatch(ctype: int, accept: string) : int
{
conv := BadConv;
(nil,l) := sys->tokenize(accept, ",");
while(l != nil) {
a := S->drop(hd l, " \t");
mt := mediatype(a, -1);
match := (ctype == mt) || (a == "*/*")
|| ((ctype == ImageXCompressed || ctype == ImageXCompressed2)
&& (mt == ImageJpeg || mt == ImageGif || mt == ImageXXBitmap));
if(match) {
if(ctype == ImageGif)
conv = Gif2xcompressed;
else if(ctype == ImageJpeg)
conv = Jpeg2xcompressed;
else if(ctype == ImageXXBitmap)
conv = Xbm2xcompressed;
else
conv = NoConv;
break;
}
l = tl l;
}
return conv;
}
# Get the body of the message whose header is in mrep,
# if io != nil.
# First check that the content type is acceptable.
# Image types will get converted into Inferno compressed format.
# If there is an error, return error string, else "".
# If no error, mrep will contain content-encoding, content-location,
# and content-type fields (guessed if they weren't orignally there).
getdata(io: ref Iobuf, m: ref Msg, accept: string, url: ref ParsedUrl) : string
{
(efnd, etype) := m.fieldval("content-encoding");
if(efnd)
return "content is encoded: " + etype;
ctype := UnknownType;
(tfnd, sctype) := m.fieldval("content-type");
if(tfnd)
ctype = mediatype(sctype, UnknownType);
else {
# try to guess type from extension
sctype = "(unknown)";
(nil, name) := S->splitr(url.path, "/");
if(name != "") {
(f, ext) := S->splitr(name, ".");
if(f != "" && ext != "") {
ctype = mediatype(ext, UnknownType);
if(ctype != UnknownType) {
sctype = mnames[ctype];
m.update("content-type", sctype);
}
}
}
}
transform := acceptmatch(ctype, accept);
if(transform == BadConv)
return "Unacceptable media type: " + sctype;
(clfnd, cloc) := m.fieldval("content-location");
if(!clfnd) {
cloc = url.tostring();
m.update("content-location", cloc);
}
if(transform != NoConv) {
rawimg: ref RImagefile->Rawimage;
err: string;
if(transform == Gif2xcompressed)
(rawimg, err) = readgif->read(io);
else if(transform == Jpeg2xcompressed)
(rawimg, err) = readjpg->read(io);
else if(transform == Xbm2xcompressed)
(rawimg, err) = readxbitmap->read(io);
# if gif file has multiple images, we are supposed to animate,
# but the first one should be there
if(err != "" && err != "ReadGIF: can't handle multiple images in file")
return "error converting image file: " + err;
(data, mask, e) := image2enc->image2enc(rawimg, 1);
if(e != "")
return "error remapping and encoding image file: " + e;
if(mask == nil)
sctype = "image/x-compressed";
else {
sctype = "image/x-compressed2";
newdata := array[len data + len mask] of byte;
newdata[0:] = data[0:];
newdata[len data:] = mask[0:];
data = newdata;
}
m.body = data;
m.bodylen = len data;
m.update("content-type", sctype);
m.update("content-length", string m.bodylen);
}
else {
# io will be nil if m came from cache
if(io != nil) {
e := m.readbody(io);
if(e != "")
return "reading body: " + e;
}
}
return "";
}
# Change an accept spec from webget client into one we can send
# to http server. This means image/x-compressed must be
# changed into image formats we can handle: i.e., gif or jpeg
fixaccept(a: string) : string
{
(nil,l) := sys->tokenize(a, ",");
ans := "";
sep := "";
while(l != nil) {
s := S->drop(hd l, " \t");
if(s == "image/x-compressed")
ans += sep + "image/gif,image/jpeg,image/x-xbitmap";
else
ans += sep + s;
sep = ",";
l = tl l;
}
if(ans == "")
ans = "*/*";
return ans;
}
log(c: ref Fid, msg: string)
{
if(logfd != nil) {
# don't use print in case msg is longer than buf
s := "";
if(c != nil)
s += (string c.fid) + ": ";
s += msg + "\n";
b := array of byte s;
sys->write(logfd, b, len b);
}
}