diff options
Diffstat (limited to 'shell/hush.c')
| -rw-r--r-- | shell/hush.c | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/shell/hush.c b/shell/hush.c index 309ed21..20b0923 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -6643,8 +6643,18 @@ struct squirrel { /* moved_to = -1: fd was opened by redirect; close orig_fd after redir */ }; +static struct squirrel *append_squirrel(struct squirrel *sq, int i, int orig, int moved) +{ + sq = xrealloc(sq, (i + 2) * sizeof(sq[0])); + sq[i].orig_fd = orig; + sq[i].moved_to = moved; + sq[i+1].orig_fd = -1; /* end marker */ + return sq; +} + static struct squirrel *add_squirrel(struct squirrel *sq, int fd, int avoid_fd) { + int moved_to; int i = 0; if (sq) while (sq[i].orig_fd >= 0) { @@ -6664,15 +6674,12 @@ static struct squirrel *add_squirrel(struct squirrel *sq, int fd, int avoid_fd) i++; } - sq = xrealloc(sq, (i + 2) * sizeof(sq[0])); - sq[i].orig_fd = fd; /* If this fd is open, we move and remember it; if it's closed, moved_to = -1 */ - sq[i].moved_to = fcntl_F_DUPFD(fd, avoid_fd); - debug_printf_redir("redirect_fd %d: previous fd is moved to %d (-1 if it was closed)\n", fd, sq[i].moved_to); - if (sq[i].moved_to < 0 && errno != EBADF) + moved_to = fcntl_F_DUPFD(fd, avoid_fd); + debug_printf_redir("redirect_fd %d: previous fd is moved to %d (-1 if it was closed)\n", fd, moved_to); + if (moved_to < 0 && errno != EBADF) xfunc_die(); - sq[i+1].orig_fd = -1; /* end marker */ - return sq; + return append_squirrel(sq, i, fd, moved_to); } /* fd: redirect wants this fd to be used (e.g. 3>file). @@ -6778,6 +6785,19 @@ static int setup_redirects(struct command *prog, struct squirrel **sqp) */ return 1; } + if (openfd == redir->rd_fd && sqp) { + /* open() gave us precisely the fd we wanted. + * This means that this fd was not busy + * (not opened to anywhere). + * Remember to close it on restore: + */ + struct squirrel *sq = *sqp; + int i = 0; + if (sq) while (sq[i].orig_fd >= 0) + i++; + *sqp = append_squirrel(sq, i, openfd, -1); /* -1 = "it was closed" */ + debug_printf_redir("redir to previously closed fd %d\n", openfd); + } } else { /* "rd_fd<*>rd_dup" or "rd_fd<*>-" cases */ openfd = redir->rd_dup; |