ref: 315776d60f1d50b7560c3d4e830c075a5d3e8828
author: rodri <rgl@antares-labs.eu>
date: Fri Mar 15 12:47:45 EDT 2024
base fs scaffolding in place.
--- /dev/null
+++ b/fs.c
@@ -1,0 +1,336 @@
+#include <u.h>
+#include <libc.h>
+#include <auth.h>
+#include <thread.h>
+#include <draw.h>
+#include <memdraw.h>
+#include <fcall.h>
+#include <9p.h>
+
+typedef struct Dirtab Dirtab;
+
+struct Dirtab
+{+ char *name;
+ uchar type;
+ uint qidpath;
+ uint perm;
+};
+
+enum {+ Qroot,
+ Qctl,
+ Qframe,
+};
+
+char Ebotch[] = "9P protocol botch";
+char Enotfound[] = "file not found";
+char Enotdir[] = "not a directory";
+char Eperm[] = "permission denied";
+
+Dirtab dirtab[] = {+ "/", QTDIR, Qroot, 0555|DMDIR,
+ "ctl", QTFILE, Qctl, 0600,
+ "frame", QTFILE, Qframe, 0444,
+};
+char *jefe = "Pablo R. Picasso";
+Memimage *fb;
+
+static int
+mode2perm(int m)
+{+ static int perms[4] = {4, 2, 6, 1};+
+ return perms[m&OMASK];
+}
+
+static void
+fillstat(Dir *dir, Dirtab *d)
+{+ dir->name = estrdup9p(d->name);
+ dir->uid = estrdup9p(jefe);
+ dir->gid = estrdup9p(jefe);
+ dir->mode = d->perm;
+ dir->length = 0;
+ dir->qid = (Qid){d->qidpath, 0, d->type};+ dir->atime = time(0);
+ dir->mtime = time(0);
+ dir->muid = estrdup9p("");+}
+
+static int
+dirgen(int n, Dir *dir, void*)
+{+ if(++n >= nelem(dirtab))
+ return -1;
+ fillstat(dir, &dirtab[n]);
+ return 0;
+}
+
+static int
+readimg(Memimage *i, char *t, Rectangle r, int offset, int n)
+{+ int ww, oo, y, m;
+ uchar *tt;
+
+ ww = bytesperline(r, i->depth);
+ r.min.y += offset/ww;
+ if(r.min.y >= r.max.y)
+ return 0;
+
+ y = r.min.y + (n + ww-1)/ww;
+ if(y < r.max.y)
+ r.max.y = y;
+
+ m = ww * Dy(r);
+ oo = offset % ww;
+ if(oo == 0 && n >= m)
+ return unloadmemimage(i, r, (uchar*)t, n);
+
+ if((tt = malloc(m)) == nil)
+ return -1;
+
+ m = unloadmemimage(i, r, tt, m) - oo;
+ if(m > 0){+ if(n < m) m = n;
+ memmove(t, tt + oo, m);
+ }
+
+ free(tt);
+ return m;
+}
+
+void
+fsattach(Req *r)
+{+ if(r->ifcall.aname && r->ifcall.aname[0]){+ respond(r, "invalid attach specifier");
+ return;
+ }
+
+ r->ofcall.qid = (Qid){Qroot, 0, QTDIR};+ r->fid->qid = r->ofcall.qid;
+ r->fid->aux = nil;
+ respond(r, nil);
+}
+
+void
+fsopen(Req *r)
+{+ int i, perm, want;
+
+ for(i = 0; i < nelem(dirtab); i++)
+ if(r->fid->qid.path == dirtab[i].qidpath)
+ break;
+
+ if(i < nelem(dirtab)){+ if(strcmp(r->fid->uid, jefe) == 0)
+ perm = dirtab[i].perm>>6;
+ else
+ perm = dirtab[i].perm;
+ }else{+ respond(r, Ebotch);
+ return;
+ };
+
+ if((r->ifcall.mode & (OTRUNC|OCEXEC|ORCLOSE)) != 0)
+ goto deny;
+ want = mode2perm(r->ifcall.mode);
+ if((want & perm) != want){+deny:
+ respond(r, Eperm);
+ return;
+ }
+ respond(r, nil);
+}
+
+void
+fsread(Req *r)
+{+ Memimage *i;
+ char buf[128], cbuf[30], *t;
+ ulong off, cnt;
+ int n;
+
+ off = r->ifcall.offset;
+ cnt = r->ifcall.count;
+
+ switch(r->fid->qid.path){+ default:
+ respond(r, "bug in fsread");
+ break;
+ case Qroot:
+ dirread9p(r, dirgen, nil);
+ respond(r, nil);
+ break;
+ case Qctl:
+ respond(r, nil);
+ break;
+ case Qframe:
+ i = fb;
+ if(off < 5*12){+ n = snprint(buf, sizeof buf, "%11s %11d %11d %11d %11d ",
+ chantostr(cbuf, i->chan),
+ i->r.min.x, i->r.min.y, i->r.max.x, i->r.max.y);
+ t = estrdup9p(buf);
+
+ if(off > n){+ off = n;
+ cnt = 0;
+ }
+
+ if(off+cnt > n)
+ cnt = n-off;
+
+ r->ofcall.data = t+off;
+ r->ofcall.count = cnt;
+ respond(r, nil);
+ free(t);
+ break;
+ }
+
+ off -= 5*12;
+ n = -1;
+ t = malloc(cnt);
+ if(t != nil){+ r->ofcall.data = t;
+ n = readimg(i, t, i->r, off, cnt);
+ }
+
+ if(n < 0){+ buf[0] = 0;
+ errstr(buf, sizeof buf);
+ respond(r, buf);
+ }else{+ r->ofcall.count = n;
+ respond(r, nil);
+ }
+ free(t);
+ break;
+ }
+}
+
+void
+fswrite(Req *r)
+{+ char *msg, *f[10];
+ ulong cnt, nf;
+ int i;
+
+ cnt = r->ifcall.count;
+
+ switch(r->fid->qid.path){+ default:
+ respond(r, "bug in fswrite");
+ break;
+ case Qctl:
+ msg = emalloc9p(cnt+1);
+ memmove(msg, r->ifcall.data, cnt);
+ msg[cnt] = 0;
+ nf = tokenize(msg, f, nelem(f));
+ for(i = 0; i < nf; i++)
+ fprint(2, "%s[%d]%s%s", i == 0? "": " ", i, f[i], i == nf-1? "\n": "");
+ free(msg);
+ r->ofcall.count = cnt;
+ respond(r, nil);
+ break;
+ }
+}
+
+void
+fsstat(Req *r)
+{+ int i;
+
+ for(i = 0; i < nelem(dirtab); i++)
+ if(r->fid->qid.path == dirtab[i].qidpath){+ fillstat(&r->d, &dirtab[i]);
+ respond(r, nil);
+ return;
+ }
+ respond(r, Enotfound);
+}
+
+char *
+fswalk1(Fid *f, char *name, Qid *qid)
+{+ int i;
+
+ switch(f->qid.path){+ case Qroot:
+ if(strcmp(name, "..") == 0){+ *qid = f->qid;
+ return nil;
+ }
+ for(i = 1; i < nelem(dirtab); i++)
+ if(strcmp(name, dirtab[i].name) == 0){+ *qid = (Qid){dirtab[i].qidpath, 0, 0};+ f->qid = *qid;
+ return nil;
+ }
+ return Enotfound;
+ default:
+ return Enotdir;
+ }
+}
+
+char *
+fsclone(Fid *old, Fid *new)
+{+ USED(old, new);
+ return nil;
+}
+
+Srv fs = {+ .attach = fsattach,
+ .open = fsopen,
+ .read = fsread,
+ .write = fswrite,
+ .stat = fsstat,
+ .walk1 = fswalk1,
+ .clone = fsclone,
+};
+
+void
+usage(void)
+{+ fprint(2, "usage: %s [-D] [-s srvname] [-m mtpt]\n", argv0);
+ exits("usage");+}
+
+void
+threadmain(int argc, char *argv[])
+{+ char *srvname, *mtpt;
+ int fd;
+
+ srvname = "render";
+ mtpt = "/mnt/render";
+ ARGBEGIN{+ case 'D':
+ chatty9p++;
+ break;
+ case 's':
+ srvname = EARGF(usage());
+ break;
+ case 'm':
+ mtpt = EARGF(usage());
+ break;
+ default: usage();
+ }ARGEND
+ if(argc != 0)
+ usage();
+
+ jefe = getuser();
+
+ fd = open("/dev/window", OREAD);+ if(fd < 0)
+ sysfatal("open: %r");+ fb = readmemimage(fd);
+ if(fb == nil)
+ sysfatal("readmemimage: %r");+ close(fd);
+
+ threadpostmountsrv(&fs, srvname, mtpt, MREPL|MCREATE);
+ exits(nil);
+}
--- /dev/null
+++ b/mkfile
@@ -1,0 +1,11 @@
+</$objtype/mkfile
+
+BIN=/$objtype/bin
+TARG=renderfs
+OFILES=\
+ fs.$O\
+
+</sys/src/cmd/mkone
+
+uninstall:V:
+ rm -f $BIN/$TARG