ref: e1cdcfdb172071bafef18b1ac160138c97459b79
dir: /sys/src/libndb/csipinfo.c/
#include <u.h> #include <libc.h> #include <bio.h> #include <ndb.h> #include <ndbhf.h> /* * look up the ip attributes 'list' for an entry that has the * given 'attr=val' and a 'ip=' tuples. * * return nil if not found. */ Ndbtuple* csipinfo(char *netroot, char *attr, char *val, char **list, int n) { Ndbtuple *t, *first, *last; int i; char line[1024]; int fd; char *p, *e; if(netroot) snprint(line, sizeof(line), "%s/cs", netroot); else strcpy(line, "/net/cs"); fd = open(line, ORDWR); if(fd < 0) return 0; seek(fd, 0, 0); e = line + sizeof(line); p = seprint(line, e, "!ipinfo %s=%s", attr, val); for(i = 0; i < n; i++){ if(*list == nil) break; p = seprint(p, e, " %s", *list++); } if(write(fd, line, strlen(line)) < 0){ close(fd); return 0; } seek(fd, 0, 0); first = last = 0; for(;;){ n = read(fd, line, sizeof(line)-2); if(n <= 0) break; line[n] = '\n'; line[n+1] = 0; t = _ndbparseline(line); if(t == 0) continue; if(first) last->entry = t; else first = t; last = t; while(last->entry) last = last->entry; } close(fd); ndbsetmalloctag(first, getcallerpc(&netroot)); return first; }