ref: 02ac617541ca1a7bf82b1615fb5a58235469b5d3
dir: /appl/alphabet/fs/mergewrite.b/
implement Mergewrite, Fsmodule; include "sys.m"; sys: Sys; include "draw.m"; include "sh.m"; include "readdir.m"; readdir: Readdir; include "alphabet/reports.m"; reports: Reports; Report, report, quit: import reports; include "alphabet/fs.m"; fs: Fs; Value: import fs; Fschan, Fsdata, Entrychan, Entry, Cmpchan, Option, Next, Down, Skip, Quit: import Fs; Mergewrite: module {}; types(): string { return "rxsm-v-n"; } VERBOSE, NOWRITE, ASSUME: con 1<<iota; init() { sys = load Sys Sys->PATH; readdir = load Readdir Readdir->PATH; if(readdir == nil){ sys->fprint(sys->fildes(2), "fs: mergewrite: cannot load %s: %r\n", Readdir->PATH); raise "fail:bad module"; } readdir->init(nil, 0); fs = load Fs Fs->PATH; if(fs == nil){ sys->fprint(sys->fildes(2), "fs: mergewrite: cannot load %s: %r\n", Fs->PATH); raise "fail:bad module"; } reports = load Reports Reports->PATH; if(reports == nil){ sys->fprint(sys->fildes(2), "fs: mergewrite: cannot load %s: %r\n", Reports->PATH); raise "fail:bad module"; } } run(nil: ref Draw->Context, report: ref Report, opts: list of Option, args: list of ref Value): ref Value { sync := chan of string; flags := 0; for(; opts != nil; opts = tl opts){ case (hd opts).opt { 'n' => flags |= NOWRITE; 'v' => flags |= VERBOSE; } } spawn fswriteproc(sync, flags, (hd args).x().i, (hd tl args).s().i, (hd tl tl args).m().i, report.start("mergewrite")); sync <-= nil; return ref Value.Vr(sync); } fswriteproc(sync: chan of string, flags: int, c: Fschan, root: string, cmp: Cmpchan, errorc: chan of string) { sys->pctl(Sys->FORKNS, nil); <-sync; if(<-sync != nil){ (<-c).t1 <-= Quit; quit(errorc); } ((d, nil), reply) := <-c; if(root != nil){ d = ref *d; d.name = root; } fswritedir(d.name, cmp, d, reply, c, errorc, flags); errorc <-= nil; sync <-= nil; # XXX should return result here... } fswritedir(path: string, cmp: Cmpchan, dir: ref Sys->Dir, dreply: chan of int, c: Fschan, errorc: chan of string, flags: int) { fd: ref Sys->FD; if(dir.mode & Sys->DMDIR){ made := 0; if(flags&VERBOSE) report(errorc, sys->sprint("create %q %uo", path, dir.mode)); if(flags&NOWRITE){ if(flags&ASSUME) made = 1; else{ fd = sys->open(dir.name, Sys->OREAD); if(fd == nil){ made = 1; flags |= ASSUME; }else if(sys->chdir(dir.name) == -1){ dreply <-= Next; report(errorc, sys->sprint("cannot cd to %q: %r", path)); return; } } }else{ fd = sys->create(dir.name, Sys->OREAD, dir.mode|8r300); made = fd != nil; if(fd == nil && (fd = sys->open(dir.name, Sys->OREAD)) == nil){ dreply <-= Next; report(errorc, sys->sprint("cannot create %q, mode %uo: %r", path, dir.mode|8r300)); return; } # XXX if we haven't just made it, we should chmod the old entry u+w to enable writing. if(sys->chdir(dir.name) == -1){ # XXX beware of names starting with '#' dreply <-= Next; report(errorc, sys->sprint("cannot cd to %q: %r", path)); fd = nil; sys->remove(dir.name); return; } } dreply <-= Down; entries: array of ref Sys->Dir; if(made == 0) entries = readdir->readall(fd, Readdir->NAME|Readdir->COMPACT).t0; i := 0; eod := 0; d0, d1: ref Sys->Dir; reply: chan of int; path[len path] = '/'; for(;;){ if(!eod && d0 == nil){ ((d0, nil), reply) = <-c; if(d0 == nil){ reply <-= Next; eod = 1; } } if(d1 == nil && i < len entries) d1 = entries[i++]; if(d0 == nil && d1 == nil) break; (wd0, wd1) := (d0, d1); if(d0 != nil && d1 != nil && d0.name != d1.name){ if(d0.name < d1.name) wd1 = nil; else wd0 = nil; } r := compare(cmp, wd0, wd1); if(wd1 != nil){ if((r & 2r10) == 0){ if(flags&VERBOSE) report(errorc, "removing "+path+wd1.name); if((flags&NOWRITE)==0){ if(wd1.mode & Sys->DMDIR) rmdir(wd1.name); else remove(wd1.name); } } d1 = nil; } if(wd0 != nil){ if((r & 2r01) == 0) reply <-= Next; else fswritedir(path + wd0.name, cmp, d0, reply, c, errorc, flags); d0 = nil; } } if((flags&ASSUME)==0) sys->chdir(".."); if((flags&NOWRITE)==0){ if((dir.mode & 8r300) != 8r300){ ws := Sys->nulldir; ws.mode = dir.mode; if(sys->fwstat(fd, ws) == -1) report(errorc, sys->sprint("cannot wstat %q: %r", path)); } } }else{ if(flags&VERBOSE) report(errorc, sys->sprint("create %q %uo", path, dir.mode)); if(flags&NOWRITE){ dreply <-= Next; return; } fd = sys->create(dir.name, Sys->OWRITE, dir.mode); if(fd == nil){ dreply <-= Next; report(errorc, sys->sprint("cannot create %q, mode %uo: %r", path, dir.mode|8r300)); return; } dreply <-= Down; while((((nil, buf), reply) := <-c).t0.data != nil){ nw := sys->write(fd, buf, len buf); if(nw < len buf){ if(nw == -1) errorc <-= sys->sprint("error writing %q: %r", path); else errorc <-= sys->sprint("short write"); reply <-= Skip; break; } reply <-= Next; } reply <-= Next; } } rmdir(name: string) { (d, n) := readdir->init(name, Readdir->NONE|Readdir->COMPACT); for(i := 0; i < n; i++){ path := name+"/"+d[i].name; if(d[i].mode & Sys->DMDIR) rmdir(path); else remove(path); } remove(name); } remove(name: string) { if(sys->remove(name) < 0) sys->fprint(sys->fildes(2), "mergewrite: cannot remove %q: %r\n", name); } compare(cmp: Cmpchan, d0, d1: ref Sys->Dir): int { mask := (d0 != nil) | (d1 != nil) << 1; if(cmp == nil) return mask; reply := chan of int; cmp <-= (d0, d1, reply); return <-reply & mask; }