ref: c116550e6a41572796e4db65e4f6acbcb3d9d6f8
dir: /appl/svc/httpd/redirect.b/
implement Redirect; include "sys.m"; sys : Sys; include "bufio.m"; bufio : Bufio; Iobuf : import bufio; include "string.m"; str : String; include "redirect.m"; HASHSIZE : con 1019; Redir: adt{ pat, repl : string; }; tab := array[HASHSIZE] of list of Redir; hashasu(key : string,n : int): int { i,h : int; i=0; h=0; while(i<len key){ h = 10*h + key[i]; h%= n; i++; } return h; } insert(pat, repl : string) { hash := hashasu(pat,HASHSIZE); tab[hash]= Redir(pat, repl) :: tab[hash]; } redirect_init(file : string) { sys = load Sys Sys->PATH; line : string; flist : list of string; n : int; bb : ref Iobuf; for(n=0;n<HASHSIZE;n++) tab[n]= nil; stderr := sys->fildes(2); bufio = load Bufio Bufio->PATH; if (bufio==nil){ sys->fprint(stderr,"redirect: cannot load %s: %r\n", Bufio->PATH); raise "fail:bad module"; } str = load String String->PATH; if (str==nil){ sys->fprint(stderr,"redirect: cannot load %s: %r\n", String->PATH); raise "fail:bad module"; } bb = bufio->open(file,bufio->OREAD); if (bb==nil) return; while((line = bb.gets('\n'))!=nil){ line = line[0:len line -1]; #chop newline if (str->in('#',line)){ (line,nil) = str->splitl(line, "#"); if (line!=nil){ n = len line; while(line[n]==' '||line[n]=='\t') n--; # and preceeding blanks line = line[0:n]; } } if (line!=nil){ (n,flist)=sys->tokenize(line,"\t "); if (n==2) insert(hd flist,hd tl flist); } } } lookup(pat : string): ref Redir { srch : list of Redir; tmp : Redir; hash : int; hash = hashasu(pat,HASHSIZE); for(srch = tab[hash]; srch!=nil; srch = tl srch){ tmp = hd srch; if(tmp.pat==nil) return nil; if(pat==tmp.pat) return ref tmp; } return nil; } redirect(path : string): string { redir : ref Redir; newpath, oldp : string; s : int; if((redir = lookup(path))!=nil) if(redir.repl==nil) return nil; else return redir.repl; for(s = len path - 1; s>0; s--){ if(path[s]=='/'){ oldp = path[s+1:]; path = path[0:s]; if((redir = lookup(path))!=nil){ if(redir.repl!=nil) newpath=sys->sprint("%s/%s", redir.repl,oldp); else newpath = nil; path = path+"/"+oldp; return newpath; } path = path+"/"+oldp; } } return nil; }