crontab: do not destroy STDIN_FILENO, editor may need it (crontab -e)

vi: deal with EOF/error on stdin and with input NULs

function                                             old     new   delta
crontab_main                                         623     642     +19
edit_file                                            901     906      +5
readit                                               331     318     -13
This commit is contained in:
Denis Vlasenko 2008-09-21 15:29:29 +00:00
parent 006e8628fc
commit 30cfdf90ce
2 changed files with 34 additions and 31 deletions

View File

@ -147,7 +147,7 @@ struct globals {
#endif
smallint editing; // >0 while we are editing a file
// [code audit says "can be 0 or 1 only"]
// [code audit says "can be 0, 1 or 2 only"]
smallint cmd_mode; // 0=command 1=insert 2=replace
int file_modified; // buffer contents changed (counter, not flag!)
int last_file_modified; // = -1;
@ -623,7 +623,7 @@ static void edit_file(char *fn)
// These are commands that change text[].
// Remember the input for the "." command
if (!adding2q && ioq_start == NULL
&& strchr(modifying_cmds, c)
&& c != '\0' && strchr(modifying_cmds, c)
) {
start_new_cmd_q(c);
}
@ -645,8 +645,8 @@ static void edit_file(char *fn)
}
//-------------------------------------------------------------------
place_cursor(rows, 0, FALSE); // go to bottom of screen
clear_to_eol(); // Erase to end of line
place_cursor(rows - 1, 0, FALSE); // go to bottom of screen
clear_to_eol(); // erase to end of line
cookmode();
#undef cur_line
}
@ -2009,9 +2009,9 @@ static void start_new_cmd_q(char c)
{
// get buffer for new cmd
// if there is a current cmd count put it in the buffer first
if (cmdcnt > 0)
if (cmdcnt > 0) {
lmc_len = sprintf(last_modifying_cmd, "%d%c", cmdcnt, c);
else { // just save char c onto queue
} else { // just save char c onto queue
last_modifying_cmd[0] = c;
lmc_len = 1;
}
@ -2163,14 +2163,14 @@ static void cont_sig(int sig UNUSED_PARAM)
signal(SIGTSTP, suspend_sig);
signal(SIGCONT, SIG_DFL);
kill(my_pid, SIGCONT);
kill(my_pid, SIGCONT); // huh? why? we are already "continued"...
}
//----- Come here when we get a Suspend signal -------------------
static void suspend_sig(int sig UNUSED_PARAM)
{
place_cursor(rows - 1, 0, FALSE); // go to bottom of screen
clear_to_eol(); // Erase to end of line
clear_to_eol(); // erase to end of line
cookmode(); // terminal to "cooked"
signal(SIGCONT, cont_sig);
@ -2247,18 +2247,20 @@ static char readit(void) // read (maybe cursor) key from stdin
fflush(stdout);
n = chars_to_parse;
// get input from User- are there already input chars in Q?
// get input from User - are there already input chars in Q?
if (n <= 0) {
// the Q is empty, wait for a typed char
again:
n = safe_read(STDIN_FILENO, readbuffer, sizeof(readbuffer));
if (n < 0) {
if (errno == EBADF || errno == EFAULT || errno == EINVAL
|| errno == EIO)
editing = 0; // want to exit
errno = 0;
if (n <= 0) {
place_cursor(rows - 1, 0, FALSE); // go to bottom of screen
clear_to_eol(); // erase to end of line
cookmode(); // terminal to "cooked"
bb_error_msg_and_die("can't read user input");
}
if (n <= 0)
return 0; // error
/* elsewhere we can get very confused by NULs */
if (readbuffer[0] == '\0')
goto again;
if (readbuffer[0] == 27) {
// This is an ESC char. Is this Esc sequence?
// Could be bare Esc key. See if there are any

View File

@ -93,6 +93,7 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
char *new_fname;
char *user_name; /* -u USER */
int fd;
int src_fd;
int opt_ler;
/* file [opts] Replace crontab from file
@ -144,15 +145,15 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
bb_show_usage();
/* Read replacement file under user's UID/GID/group vector */
src_fd = STDIN_FILENO;
if (!opt_ler) { /* Replace? */
if (!argv[0])
bb_show_usage();
if (NOT_LONE_DASH(argv[0])) {
fd = open_as_user(pas, argv[0]);
if (fd < 0)
src_fd = open_as_user(pas, argv[0]);
if (src_fd < 0)
bb_error_msg_and_die("user %s cannot read %s",
pas->pw_name, argv[0]);
xmove_fd(fd, STDIN_FILENO);
}
}
@ -180,23 +181,23 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
tmp_fname = xasprintf("%s.%u", crontab_dir, (unsigned)getpid());
/* No O_EXCL: we don't want to be stuck if earlier crontabs
* were killed, leaving stale temp file behind */
fd = xopen3(tmp_fname, O_RDWR|O_CREAT|O_TRUNC, 0600);
xmove_fd(fd, STDIN_FILENO);
fchown(STDIN_FILENO, pas->pw_uid, pas->pw_gid);
src_fd = xopen3(tmp_fname, O_RDWR|O_CREAT|O_TRUNC, 0600);
fchown(src_fd, pas->pw_uid, pas->pw_gid);
fd = open(pas->pw_name, O_RDONLY);
if (fd >= 0) {
bb_copyfd_eof(fd, STDIN_FILENO);
bb_copyfd_eof(fd, src_fd);
close(fd);
xlseek(src_fd, 0, SEEK_SET);
}
close_on_exec_on(src_fd); /* don't want editor to see this fd */
edit_file(pas, tmp_fname);
xlseek(STDIN_FILENO, 0, SEEK_SET);
/* fall through */
case 0: /* Replace (no -l, -e, or -r were given) */
new_fname = xasprintf("%s.new", pas->pw_name);
fd = open(new_fname, O_WRONLY|O_CREAT|O_TRUNC|O_APPEND, 0600);
if (fd >= 0) {
bb_copyfd_eof(STDIN_FILENO, fd);
bb_copyfd_eof(src_fd, fd);
close(fd);
xrename(new_fname, pas->pw_name);
} else {