ref: 890b97fa08c541e020888c2514cadebe8b812d2e
dir: /sys/src/cmd/snap/snapfs.c/
#include <u.h> #include <libc.h> #include <bio.h> #include <auth.h> #include <fcall.h> #include <thread.h> #include <9p.h> #include "snap.h" typedef struct PD PD; struct PD { int isproc; union { Proc *p; Data *d; }; }; PD* PDProc(Proc *p) { PD *pd; pd = emalloc(sizeof(*pd)); pd->isproc = 1; pd->p = p; return pd; } PD* PDData(Data *d) { PD *pd; pd = emalloc(sizeof(*pd)); pd->isproc = 0; pd->d = d; return pd; } void usage(void) { fprint(2, "usage: snapfs [-a] [-m mtpt] file\n"); exits("usage"); } char* memread(Proc *p, File *f, void *buf, long *count, vlong offset) { Page *pg; int po; po = offset%Pagesize; if(!(pg = findpage(p, p->pid, f->name[0], offset-po))) return "address not mapped"; if(*count > Pagesize-po) *count = Pagesize-po; memmove(buf, pg->data+po, *count); return nil; } char* dataread(Data *d, void *buf, long *count, vlong offset) { assert(d != nil); if(offset >= d->len) { *count = 0; return nil; } if(offset+*count >= d->len) *count = d->len - offset; memmove(buf, d->data+offset, *count); return nil; } void fsread(Req *r) { char *e; PD *pd; Fid *fid; void *data; vlong offset; long count; fid = r->fid; data = r->ofcall.data; offset = r->ifcall.offset; count = r->ifcall.count; pd = fid->file->aux; if(pd->isproc) e = memread(pd->p, fid->file, data, &count, offset); else e = dataread(pd->d, data, &count, offset); if(e == nil) r->ofcall.count = count; respond(r, e); } Srv fs = { .read = fsread, }; File* ecreatefile(File *a, char *b, char *c, ulong d, void *e) { File *f; f = createfile(a, b, c, d, e); if(f == nil) sysfatal("error creating snap tree: %r"); return f; } void main(int argc, char **argv) { Biobuf *b; Data *d; File *fdir, *f; Proc *p, *plist; Tree *tree; char *mtpt, buf[32]; int i, mflag; mtpt = "/proc"; mflag = MBEFORE; ARGBEGIN{ case 'D': chatty9p++; break; case 'd': debug++; break; case 'a': mflag = MAFTER; break; case 'm': mtpt = ARGF(); break; default: usage(); }ARGEND if(argc != 1) usage(); if((b = Bopen(argv[0], OREAD)) == nil) sysfatal("cannot open \"%s\": %r", argv[0]); if((plist = readsnap(b)) == nil) sysfatal("readsnap fails"); tree = alloctree(nil, nil, DMDIR|0555, nil); fs.tree = tree; for(p=plist; p; p=p->link) { print("process %ld %.*s\n", p->pid, 28, p->d[Pstatus] ? p->d[Pstatus]->data : ""); snprint(buf, sizeof buf, "%ld", p->pid); fdir = ecreatefile(tree->root, buf, nil, DMDIR|0555, nil); ecreatefile(fdir, "ctl", nil, 0777, nil); if(p->text) ecreatefile(fdir, "text", nil, 0777, PDProc(p)); ecreatefile(fdir, "mem", nil, 0666, PDProc(p)); for(i=0; i<Npfile; i++) { if(d = p->d[i]) { f = ecreatefile(fdir, pfile[i], nil, 0666, PDData(d)); f->length = d->len; } } } postmountsrv(&fs, nil, mtpt, mflag); exits(0); }