ref: ea413b4a62be9993e4b63bf237f0b1d482f4aafa
dir: /sys/src/cmd/upas/common/libsys.c/
#include "common.h" #include <auth.h> #include <ndb.h> /* * return the date */ char* thedate(void) { static char now[64]; strcpy(now, ctime(time(0))); now[28] = 0; return now; } /* * return the user id of the current user */ char * getlog(void) { return getuser(); } /* * return the lock name (we use one lock per directory) */ static void lockname(Mlock *l, char *path) { char *e, *q; seprint(l->name, e = l->name+sizeof l->name, "%s", path); q = strrchr(l->name, '/'); if(q == nil) q = l->name; else q++; seprint(q, e, "%s", "L.mbox"); } int syscreatelocked(char *path, int mode, int perm) { return create(path, mode, DMEXCL|perm); } int sysopenlocked(char *path, int mode) { /* return open(path, OEXCL|mode);/**/ return open(path, mode); /* until system call is fixed */ } int sysunlockfile(int fd) { return close(fd); } /* * try opening a lock file. If it doesn't exist try creating it. */ static int openlockfile(Mlock *l) { int fd; Dir *d, nd; char *p; l->fd = open(l->name, OREAD); if(l->fd >= 0) return 0; if(d = dirstat(l->name)){ free(d); return 1; /* try again later */ } l->fd = create(l->name, OREAD, DMEXCL|0666); if(l->fd >= 0){ nulldir(&nd); nd.mode = DMEXCL|0666; if(dirfwstat(l->fd, &nd) < 0){ /* if we can't chmod, don't bother */ /* live without the lock but log it */ close(l->fd); l->fd = -1; syslog(0, "mail", "lock error: %s: %r", l->name); remove(l->name); } return 0; } /* couldn't create; let's see what we can whine about */ p = strrchr(l->name, '/'); if(p != 0){ *p = 0; fd = access(l->name, 2); *p = '/'; }else fd = access(".", 2); if(fd < 0) /* live without the lock but log it */ syslog(0, "mail", "lock error: %s: %r", l->name); close(fd); return 0; } #define LSECS 5*60 /* * Set a lock for a particular file. The lock is a file in the same directory * and has L. prepended to the name of the last element of the file name. */ Mlock* syslock(char *path) { Mlock *l; int tries; l = mallocz(sizeof(Mlock), 1); if(l == 0) return nil; lockname(l, path); /* * wait LSECS seconds for it to unlock */ for(tries = 0; tries < LSECS*2; tries++) switch(openlockfile(l)){ case 0: return l; case 1: sleep(500); break; } free(l); return nil; } /* * like lock except don't wait */ Mlock * trylock(char *path) { char buf[1]; int fd; Mlock *l; l = mallocz(sizeof(Mlock), 1); if(l == 0) return 0; lockname(l, path); if(openlockfile(l) != 0){ free(l); return 0; } /* fork process to keep lock alive */ switch(l->pid = rfork(RFPROC)){ default: break; case 0: fd = l->fd; for(;;){ sleep(1000*60); if(pread(fd, buf, 1, 0) < 0) break; } _exits(nil); } return l; } void syslockrefresh(Mlock *l) { char buf[1]; pread(l->fd, buf, 1, 0); } void sysunlock(Mlock *l) { if(l == 0) return; close(l->fd); if(l->pid > 0) postnote(PNPROC, l->pid, "time to die"); free(l); } /* * Open a file. The modes are: * * l - locked * a - set append permissions * r - readable * w - writable * A - append only (doesn't exist in Bio) */ Biobuf* sysopen(char *path, char *mode, ulong perm) { int sysperm, sysmode, fd, docreate, append, truncate; Dir *d, nd; Biobuf *bp; /* * decode the request */ sysperm = 0; sysmode = -1; docreate = 0; append = 0; truncate = 0; for(; *mode; mode++) switch(*mode){ case 'A': sysmode = OWRITE; append = 1; break; case 'c': docreate = 1; break; case 'l': sysperm |= DMEXCL; break; case 'a': sysperm |= DMAPPEND; break; case 'w': if(sysmode == -1) sysmode = OWRITE; else sysmode = ORDWR; break; case 'r': if(sysmode == -1) sysmode = OREAD; else sysmode = ORDWR; break; case 't': truncate = 1; break; default: break; } switch(sysmode){ case OREAD: case OWRITE: case ORDWR: break; default: if(sysperm&DMAPPEND) sysmode = OWRITE; else sysmode = OREAD; break; } /* * create file if we need to */ if(truncate) sysmode |= OTRUNC; fd = open(path, sysmode); if(fd < 0){ d = dirstat(path); if(d == nil){ if(docreate == 0) return 0; fd = create(path, sysmode, sysperm|perm); if(fd < 0) return 0; nulldir(&nd); nd.mode = sysperm|perm; dirfwstat(fd, &nd); } else { free(d); return 0; } } bp = (Biobuf*)malloc(sizeof(Biobuf)); if(bp == 0){ close(fd); return 0; } memset(bp, 0, sizeof(Biobuf)); Binit(bp, fd, sysmode&~OTRUNC); if(append) Bseek(bp, 0, 2); return bp; } /* * close the file, etc. */ int sysclose(Biobuf *bp) { int rv; rv = Bterm(bp); close(Bfildes(bp)); free(bp); return rv; } /* * make a directory */ int sysmkdir(char *file, ulong perm) { int fd; if((fd = create(file, OREAD, DMDIR|perm)) < 0) return -1; close(fd); return 0; } /* * read in the system name */ char * sysname_read(void) { static char name[128]; char *s, *c; c = s = getenv("site"); if(!c) c = alt_sysname_read(); if(!c) c = "kremvax"; strecpy(name, name+sizeof name, c); free(s); return name; } char * alt_sysname_read(void) { return sysname(); } /* * get all names */ char** sysnames_read(void) { int n; Ndbtuple *t, *nt; static char **namev; if(namev) return namev; free(csgetvalue(0, "sys", sysname(), "dom", &t)); n = 0; for(nt = t; nt; nt = nt->entry) if(strcmp(nt->attr, "dom") == 0) n++; namev = (char**)malloc(sizeof(char *)*(n+3)); if(namev){ namev[0] = strdup(sysname_read()); namev[1] = strdup(alt_sysname_read()); n = 2; for(nt = t; nt; nt = nt->entry) if(strcmp(nt->attr, "dom") == 0) namev[n++] = strdup(nt->val); namev[n] = 0; } if(t) ndbfree(t); return namev; } /* * read in the domain name */ char* domainname_read(void) { char **p; for(p = sysnames_read(); *p; p++) if(strchr(*p, '.')) return *p; return 0; } /* * rename a file, fails unless both are in the same directory */ int sysrename(char *old, char *new) { Dir d; char *obase; char *nbase; obase = strrchr(old, '/'); nbase = strrchr(new, '/'); if(obase){ if(nbase == 0) return -1; if(strncmp(old, new, obase-old) != 0) return -1; nbase++; } else { if(nbase) return -1; nbase = new; } nulldir(&d); d.name = nbase; return dirwstat(old, &d); } int sysexist(char *file) { return access(file, AEXIST) == 0; } static char yankeepig[] = "die: yankee pig dog"; int syskill(int pid) { return postnote(PNPROC, pid, yankeepig); } int syskillpg(int pid) { return postnote(PNGROUP, pid, yankeepig); } int sysdetach(void) { if(rfork(RFENVG|RFNAMEG|RFNOTEG) < 0) { werrstr("rfork failed"); return -1; } return 0; } /* * catch a write on a closed pipe */ static int *closedflag; static int catchpipe(void *, char *msg) { static char *foo = "sys: write on closed pipe"; if(strncmp(msg, foo, strlen(foo)) == 0){ if(closedflag) *closedflag = 1; return 1; } return 0; } void pipesig(int *flagp) { closedflag = flagp; atnotify(catchpipe, 1); } void pipesigoff(void) { atnotify(catchpipe, 0); } int islikeatty(int fd) { char buf[64]; int l; if(fd2path(fd, buf, sizeof buf) != 0) return 0; /* might be /mnt/term/dev/cons */ l = strlen(buf); return l >= 9 && strcmp(buf+l-9, "/dev/cons") == 0; } int holdon(void) { int fd; if(!islikeatty(0)) return -1; fd = open("/dev/consctl", OWRITE); write(fd, "holdon", 6); return fd; } int sysopentty(void) { return open("/dev/cons", ORDWR); } void holdoff(int fd) { write(fd, "holdoff", 7); close(fd); } int sysfiles(void) { return 128; } /* * expand a path relative to the user's mailbox directory * * if the path starts with / or ./, don't change it * */ char* mboxpathbuf(char *to, int n, char *user, char *path) { if(*path == '/' || !strncmp(path, "./", 2) || !strncmp(path, "../", 3)) snprint(to, n, "%s", path); else snprint(to, n, "%s/box/%s/%s", MAILROOT, user, path); return to; } /* * warning: we're not quoting bad characters. we're not encoding * non-ascii characters. basically this function sucks. don't use. */ char* username0(Biobuf *b, char *from) { char *p, *f[6]; int n; static char buf[32]; n = strlen(from); buf[0] = 0; for(;; free(p)) { p = Brdstr(b, '\n', 1); if(p == 0) break; if(strncmp(p, from, n) || p[n] != '|') continue; if(getfields(p, f, nelem(f), 0, "|") < 3) continue; snprint(buf, sizeof buf, "\"%s\"", f[2]); /* no break; last match wins */ } return buf[0]? buf: 0; } char* username(char *from) { char *s; Biobuf *b; s = 0; if(b = Bopen("/adm/keys.who", OREAD)){ s = username0(b, from); Bterm(b); } if(s == 0 && (b = Bopen("/adm/netkeys.who", OREAD))){ s = username0(b, from); Bterm(b); } return s; } /* * create a file and * 1) ensure the modes we asked for * 2) make gid == uid */ static int docreate(char *file, int perm) { int fd; Dir ndir; Dir *d; /* create the mbox */ fd = create(file, OREAD, perm); if(fd < 0){ fprint(2, "couldn't create %s\n", file); return -1; } d = dirfstat(fd); if(d == nil){ fprint(2, "couldn't stat %s\n", file); return -1; } nulldir(&ndir); ndir.mode = perm; ndir.gid = d->uid; if(dirfwstat(fd, &ndir) < 0) fprint(2, "couldn't chmod %s: %r\n", file); close(fd); return 0; } static int createfolder0(char *user, char *folder, char *ftype) { char *p, *s, buf[Pathlen]; int isdir, mode; Dir *d; assert(folder != 0); mboxpathbuf(buf, sizeof buf, user, folder); if(access(buf, 0) == 0){ fprint(2, "%s already exists\n", ftype); return -1; } fprint(2, "creating new %s: %s\n", ftype, buf); /* * if we can deliver to this mbox, it needs * to be read/execable all the way down */ mode = 0711; if(!strncmp(buf, "/mail/box/", 10)) if((s = strrchr(buf, '/')) && !strcmp(s+1, "mbox")) mode = 0755; for(p = buf; p; p++) { if(*p == '/') continue; p = strchr(p, '/'); if(p == 0) break; *p = 0; if(access(buf, 0) != 0) if(docreate(buf, DMDIR|mode) < 0) return -1; *p = '/'; } /* must match folder.c:/^openfolder */ isdir = create(buf, OREAD, DMDIR|0777); /* * make sure everyone can write here if it's a mailbox * rather than a folder */ if(mode == 0755) if(isdir >= 0 && (d = dirfstat(isdir))){ d->mode |= 0773; dirfwstat(isdir, d); free(d); } if(isdir == -1){ fprint(2, "can't create %s: %s\n", ftype, buf); return -1; } close(isdir); return 0; } int createfolder(char *user, char *folder) { return createfolder0(user, folder, "folder"); } int creatembox(char *user, char *mbox) { char buf[Pathlen]; if(mbox == 0) snprint(buf, sizeof buf, "mbox"); else snprint(buf, sizeof buf, "%s/mbox", mbox); return createfolder0(user, buf, "mbox"); }