/* ISC license. */ #include #include #include #include static inline int lockex (int fd, int blocking) { return blocking ? lock_ex(fd) : lock_exnb(fd) ; } static inline int locksh (int fd, int blocking) { return blocking ? lock_sh(fd) : lock_shnb(fd) ; } int s6rc_lock (char const *live, int lwhat, int *llfd, char const *compiled, int cwhat, int *ccfd, int blocking) { int e = 0 ; int lfd = -1, cfd = -1 ; if (lwhat) { size_t llen = strlen(live) ; char lfn[llen + 6] ; memcpy(lfn, live, llen) ; memcpy(lfn + llen, "/lock", 6) ; lfd = open_create(lfn) ; if (lfd < 0) return 0 ; if ((lwhat > 1 ? lockex(lfd, blocking) : locksh(lfd, blocking)) < 0) { e = errno ; goto lerr ; } } if (cwhat) { size_t clen = strlen(compiled) ; char cfn[clen + 6] ; memcpy(cfn, compiled, clen) ; memcpy(cfn + clen, "/lock", 6) ; cfd = open_create(cfn) ; if (cfd < 0) if (cwhat > 1 || errno != EROFS) { e = errno ; goto lerr ; } else cfd = -errno ; else if ((cwhat > 1 ? lockex(cfd, blocking) : locksh(cfd, blocking)) < 0) { e = errno ; goto cerr ; } } if (lwhat) *llfd = lfd ; if (cwhat) *ccfd = cfd ; return 1 ; cerr: fd_close(cfd) ; lerr: if (lwhat) fd_close(lfd) ; errno = e ; return 0 ; }