ref: 1d891d163e814a93ee5346cf05b4fac297bf3a5c
dir: /sys/src/ape/lib/ap/plan9/fcntl.c/
#include "lib.h" #include <unistd.h> #include <errno.h> #include <stdarg.h> #include "sys9.h" /* * BUG: advisory locking not implemented */ #define OFL (O_ACCMODE|O_NONBLOCK|O_APPEND) int fcntl(int fd, int cmd, ...) { int arg, i, ans, err; Fdinfo *fi, *fans; va_list va; unsigned long oflags; err = 0; ans = 0; va_start(va, cmd); arg = va_arg(va, int); va_end(va); fi = &_fdinfo[fd]; if(fd<0 || fd>=OPEN_MAX || !(fi->flags&FD_ISOPEN)) err = EBADF; else switch(cmd){ case F_DUPFD: if(fi->flags&(FD_BUFFERED|FD_BUFFEREDX)){ err = EGREG; /* dup of buffered fd not implemented */ break; } oflags = fi->oflags; for(i = (arg>0)? arg : 0; i<OPEN_MAX; i++) if(!(_fdinfo[i].flags&FD_ISOPEN)) break; if(i == OPEN_MAX) err = EMFILE; else { ans = _DUP(fd, i); if(ans != i){ if(ans < 0){ _syserrno(); err = errno; }else err = EBADF; }else{ fans = &_fdinfo[ans]; fans->flags = fi->flags&~FD_CLOEXEC; fans->oflags = oflags; fans->uid = fi->uid; fans->gid = fi->gid; } } break; case F_GETFD: ans = fi->flags&FD_CLOEXEC; break; case F_SETFD: fi->flags = (fi->flags&~FD_CLOEXEC)|(arg&FD_CLOEXEC); break; case F_GETFL: ans = fi->oflags&OFL; break; case F_SETFL: fi->oflags = (fi->oflags&~OFL)|(arg&OFL); break; case F_GETLK: case F_SETLK: case F_SETLKW: err = EINVAL; break; } if(err){ errno = err; ans = -1; } return ans; }