>From man siglongjmp(3) 'longjmp() and siglongjmp() make programs hard to
understand and maintain. If possible, an alternative should be used.'
Signed-off-by: Sami Kerola <kerolasa@xxxxxx>
---
text-utils/more.c | 246 +++++++++++++++++++++++++++++-------------------------
1 file changed, 133 insertions(+), 113 deletions(-)
diff --git a/text-utils/more.c b/text-utils/more.c
index 5586e69..9a3d96b 100644
--- a/text-utils/more.c
+++ b/text-utils/more.c
@@ -43,12 +43,13 @@
* modified mem allocation handling for util-linux
*/
+#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
+#include <poll.h>
#include <regex.h>
-#include <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
@@ -57,6 +58,7 @@
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/param.h>
+#include <sys/signalfd.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <termios.h>
@@ -72,6 +74,7 @@
#include "closestream.h"
#include "nls.h"
+#include "rpmatch.h"
#include "strutils.h"
#include "widechar.h"
#include "xalloc.h"
@@ -99,6 +102,7 @@
#define COMMAND_BUF 200
#define REGERR_BUF NUM_COLUMNS
#define STOP -10
+#define SEARCH_TIMEOUT 10
struct more_control {
struct termios otty; /* output terminal */
@@ -115,7 +119,7 @@ struct more_control {
int nfiles; /* number of files left to process */
char *shell; /* the name of the shell to use */
int shellp; /* does previous shell command exists */
- sigjmp_buf restore; /* siglongjmp() destination */
+ int sigfd; /* signalfd() file descriptor */
char *Line; /* line buffer */
size_t LineLen; /* size of line buffer */
int Lpp; /* lines per page */
@@ -161,7 +165,6 @@ struct more_control {
hard:1, /* is this hard copy terminal */
hardtabs:1, /* print spaces instead of '\t' */
jumpopt:1, /* is jumpline defined */
- inwait:1, /* is waiting user input */
lastp:1, /* run previous key command */
noscroll:1, /* do not scroll, clear the screen and then display text */
notell:1, /* suppress quit dialog */
@@ -172,17 +175,14 @@ struct more_control {
pstate:1, /* is underlining going on */
soglitch:1, /* terminal has standout mode glitch */
srchopt:1, /* is init search pattern defined */
+ search_called:1, /* previous more command was a search */
ssp_opt:1, /* suppress white space */
- startup:1, /* is startup completed */
stop_opt:1, /* stop after form feeds */
ulglitch:1, /* terminal is underlining in glitch mode */
ul_opt:1, /* underline as best we can */
within:1, /* true if we are within a file, false if we are between files */
Wrap:1; /* set if automargins */
};
-/* FIXME: the global_ctl is used in signal handlers, until the signal
- * handling is corrected to use signalfd(). */
-struct more_control *global_ctl;
static void __attribute__((__noreturn__)) usage(FILE *out)
{
@@ -696,7 +696,6 @@ static void prompt(struct more_control *ctl, char *filename)
fflush(stdout);
} else
fputc('\a', stderr);
- ctl->inwait = 1;
}
static void reset_tty(struct more_control *ctl)
@@ -715,20 +714,20 @@ static void reset_tty(struct more_control *ctl)
}
/* Clean up terminal state and exit. Also come here if interrupt signal received */
-static void __attribute__((__noreturn__)) end_it(int dummy __attribute__((__unused__)))
+static void __attribute__((__noreturn__)) end_it(struct more_control *ctl)
{
- reset_tty(global_ctl);
- if (global_ctl->clreol) {
+ reset_tty(ctl);
+ if (ctl->clreol) {
putchar('\r');
- my_putstring(global_ctl->EodClr);
+ my_putstring(ctl->EodClr);
fflush(stdout);
- } else if (!global_ctl->clreol && (global_ctl->promptlen > 0)) {
- kill_line(global_ctl);
+ } else if (!ctl->clreol && (ctl->promptlen > 0)) {
+ kill_line(ctl);
fflush(stdout);
} else
fputc('\n', stderr);
- free(global_ctl->previousre);
- free(global_ctl->Line);
+ free(ctl->previousre);
+ free(ctl->Line);
_exit(EXIT_SUCCESS);
}
@@ -739,7 +738,7 @@ static int readch(struct more_control *ctl)
errno = 0;
if (read(STDERR_FILENO, &c, 1) <= 0) {
if (errno != EINTR)
- end_it(0);
+ end_it(ctl);
else
c = ctl->otty.c_cc[VKILL];
}
@@ -822,7 +821,6 @@ static void more_error(struct more_control *ctl, char *mess)
fputs(mess, stdout);
fflush(stdout);
ctl->errors++;
- siglongjmp(ctl->restore, 1);
}
static void erase_one_column(struct more_control *ctl)
@@ -911,7 +909,6 @@ static void ttyin(struct more_control *ctl, char buf[], int nmax, char pchar)
} else {
if (!ctl->eraseln)
ctl->promptlen = maxlen;
- siglongjmp(ctl->restore, 1);
}
} else if (((cc_t) c == ctl->otty.c_cc[VKILL]) && !slash) {
if (ctl->hard) {
@@ -1019,51 +1016,23 @@ static void set_tty(struct more_control *ctl)
}
/* Come here if a quit signal is received */
-static void onquit(int dummy __attribute__((__unused__)))
+static void onquit(struct more_control *ctl)
{
- signal(SIGQUIT, SIG_IGN);
- if (!global_ctl->inwait) {
- putchar('\n');
- if (!global_ctl->startup) {
- signal(SIGQUIT, onquit);
- siglongjmp(global_ctl->restore, 1);
- } else
- global_ctl->Pause = 1;
- } else if (!global_ctl->dum_opt && global_ctl->notell) {
- global_ctl->promptlen += fprintf(stderr, _("[Use q or Q to quit]"));
- global_ctl->notell = 0;
- }
- signal(SIGQUIT, onquit);
+ if (!ctl->dum_opt && ctl->notell) {
+ ctl->promptlen += fprintf(stderr, _("[Use q or Q to quit]"));
+ ctl->notell = 0;
+ } else
+ end_it(ctl);
}
/* Come here when we get a suspend signal from the terminal */
-static void onsusp(int dummy __attribute__((__unused__)))
+static void onsusp(struct more_control *ctl)
{
- sigset_t signals, oldmask;
-
- /* ignore SIGTTOU so we don't get stopped if csh grabs the tty */
- signal(SIGTTOU, SIG_IGN);
- reset_tty(global_ctl);
+ reset_tty(ctl);
fflush(stdout);
- signal(SIGTTOU, SIG_DFL);
- /* Send the TSTP signal to suspend our process group */
- signal(SIGTSTP, SIG_DFL);
-
- /* unblock SIGTSTP or we won't be able to suspend ourself */
- sigemptyset(&signals);
- sigaddset(&signals, SIGTSTP);
- sigprocmask(SIG_UNBLOCK, &signals, &oldmask);
-
- kill(0, SIGTSTP);
- /* Pause for station break */
-
- sigprocmask(SIG_SETMASK, &oldmask, NULL);
-
+ kill(0, SIGSTOP);
/* We're back */
- signal(SIGTSTP, onsusp);
- set_tty(global_ctl);
- if (global_ctl->inwait)
- siglongjmp(global_ctl->restore, 1);
+ set_tty(ctl);
}
static void execute(struct more_control *ctl, char *filename, char *cmd, ...)
@@ -1115,15 +1084,8 @@ static void execute(struct more_control *ctl, char *filename, char *cmd, ...)
exit(EXIT_FAILURE);
}
if (id > 0) {
- signal(SIGINT, SIG_IGN);
- signal(SIGQUIT, SIG_IGN);
- if (ctl->catch_susp)
- signal(SIGTSTP, SIG_DFL);
while (wait(0) > 0)
/* nothing */ ;
- signal(SIGQUIT, onquit);
- if (ctl->catch_susp)
- signal(SIGTSTP, onsusp);
} else
fputs(_("can't fork\n"), stderr);
set_tty(ctl);
@@ -1195,7 +1157,7 @@ static int colon(struct more_control *ctl, char *filename, int cmd, int nlines)
case 'n':
if (nlines == 0) {
if (ctl->fnum >= ctl->nfiles - 1)
- end_it(0);
+ end_it(ctl);
nlines++;
}
putchar('\r');
@@ -1218,7 +1180,7 @@ static int colon(struct more_control *ctl, char *filename, int cmd, int nlines)
return -1;
case 'q':
case 'Q':
- end_it(0);
+ end_it(ctl);
default:
fputc('\a', stderr);
return -1;
@@ -1267,6 +1229,26 @@ static void rdline(struct more_control *ctl, FILE *f)
*p = '\0';
}
+volatile sig_atomic_t alarm_received;
+
+static void sig_alarm_handler(int sig __attribute__((__unused__)))
+{
+ alarm_received = 1;
+}
+
+static int stop_search(struct more_control *ctl)
+{
+ char buf[2];
+
+ ctl->promptlen = printf(_("No search results in %d seconds, stop searching?"), SEARCH_TIMEOUT);
+ buf[0] = getchar();
+ buf[1] = '\0';
+ erasep(ctl, 0);
+ alarm(SEARCH_TIMEOUT);
+ alarm_received = 0;
+ return rpmatch(buf);
+}
+
/* Search for nth occurrence of regular expression contained in buf in
* the file */
static void search(struct more_control *ctl, char buf[], FILE *file, int n)
@@ -1288,8 +1270,14 @@ static void search(struct more_control *ctl, char buf[], FILE *file, int n)
char s[REGERR_BUF];
regerror(rc, &re, s, sizeof s);
more_error(ctl, s);
+ return;
}
+ alarm_received = 0;
+ signal(SIGALRM, sig_alarm_handler);
+ alarm(SEARCH_TIMEOUT);
while (!feof(file)) {
+ if (alarm_received && stop_search(ctl))
+ break;
line3 = line2;
line2 = line1;
line1 = ctl->file_pos;
@@ -1329,6 +1317,8 @@ static void search(struct more_control *ctl, char buf[], FILE *file, int n)
}
}
}
+ alarm(0);
+ signal(SIGALRM, SIG_DFL);
regfree(&re);
if (feof(file)) {
if (!ctl->no_intty) {
@@ -1336,7 +1326,7 @@ static void search(struct more_control *ctl, char buf[], FILE *file, int n)
set_pos_fseek(ctl, file, startline);
} else {
fputs(_("\nPattern not found\n"), stdout);
- end_it(0);
+ end_it(ctl);
}
free(ctl->previousre);
ctl->previousre = NULL;
@@ -1467,6 +1457,26 @@ static int skip_forwards(struct more_control *ctl, FILE *f, int nlines, char com
return 1;
}
+/* Come here if a signal for a window size change is received */
+#ifdef SIGWINCH
+static void chgwinsz(struct more_control *ctl)
+{
+ struct winsize win;
+
+ if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) != -1) {
+ if (win.ws_row != 0) {
+ ctl->Lpp = win.ws_row;
+ ctl->nscroll = ctl->Lpp / 2 - 1;
+ if (ctl->nscroll <= 0)
+ ctl->nscroll = 1;
+ ctl->dlines = ctl->Lpp - 1;
+ }
+ if (win.ws_col != 0)
+ ctl->Mcol = win.ws_col;
+ }
+}
+#endif /* SIGWINCH */
+
/* Read a command and do it. A command consists of an optional integer
* argument followed by the command character. Return the number of
* lines to display in the next screenful. If there is nothing more to
@@ -1478,12 +1488,51 @@ static int command(struct more_control *ctl, char *filename, FILE *f)
char colonch;
int done = 0;
char comchar, cmdbuf[INIT_BUF];
+ struct pollfd pfd[2];
+ pfd[0].fd = ctl->sigfd;
+ pfd[0].events = POLLIN | POLLERR | POLLHUP;
+ pfd[1].fd = STDIN_FILENO;
+ pfd[1].events = POLLIN;
if (!ctl->errors)
prompt(ctl, filename);
else
ctl->errors = 0;
+ ctl->search_called = 0;
while (!done) {
+ if (poll(pfd, 2, -1) < 0) {
+ if (errno == EAGAIN)
+ continue;
+ more_error(ctl, _("poll failed"));
+ continue;
+ }
+ if (pfd[0].revents != 0) {
+ struct signalfd_siginfo info;
+ ssize_t sz;
+
+ sz = read(pfd[0].fd, &info, sizeof(info));
+ assert(sz == sizeof(info));
+ switch (info.ssi_signo) {
+ case SIGINT:
+ end_it(ctl);
+ break;
+ case SIGQUIT:
+ onquit(ctl);
+ break;
+ case SIGTSTP:
+ onsusp(ctl);
+ break;
+#ifdef SIGWINCH
+ case SIGWINCH:
+ chgwinsz(ctl);
+ break;
+#endif
+ default:
+ abort();
+ }
+ }
+ if (pfd[1].revents == 0)
+ continue;
nlines = number(ctl, &comchar);
ctl->lastp = colonch = 0;
if (comchar == '.') { /* Repeat last command */
@@ -1533,7 +1582,7 @@ static int command(struct more_control *ctl, char *filename, FILE *f)
break;
case 'q':
case 'Q':
- end_it(0);
+ end_it(ctl);
case 's':
case 'f':
case ctrl('F'):
@@ -1587,6 +1636,7 @@ static int command(struct more_control *ctl, char *filename, FILE *f)
ctl->lastp = 1;
/* fall through */
case '/':
+ ctl->search_called = 1;
if (nlines == 0)
nlines++;
kill_line(ctl);
@@ -1643,7 +1693,6 @@ static int command(struct more_control *ctl, char *filename, FILE *f)
}
}
putchar('\r');
- ctl->inwait = 0;
ctl->notell = 1;
return retval;
}
@@ -1699,11 +1748,11 @@ static void screen(struct more_control *ctl, FILE *f, int num_lines)
if (ctl->Pause && ctl->clreol)
my_putstring(ctl->EodClr);
more_ungetc(ctl, c, f);
- sigsetjmp(ctl->restore, 1);
ctl->Pause = 0;
- ctl->startup = 0;
- if ((num_lines = command(ctl, NULL, f)) == 0)
- return;
+ do {
+ if ((num_lines = command(ctl, NULL, f)) == 0)
+ return;
+ } while (ctl->search_called && !ctl->previousre);
if (ctl->hard && ctl->promptlen > 0)
erasep(ctl, 0);
if (ctl->noscroll && num_lines >= ctl->dlines) {
@@ -1717,28 +1766,6 @@ static void screen(struct more_control *ctl, FILE *f, int num_lines)
}
}
-/* Come here if a signal for a window size change is received */
-#ifdef SIGWINCH
-static void chgwinsz(int dummy __attribute__((__unused__)))
-{
- struct winsize win;
-
- signal(SIGWINCH, SIG_IGN);
- if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) != -1) {
- if (win.ws_row != 0) {
- global_ctl->Lpp = win.ws_row;
- global_ctl->nscroll = global_ctl->Lpp / 2 - 1;
- if (global_ctl->nscroll <= 0)
- global_ctl->nscroll = 1;
- global_ctl->dlines = global_ctl->Lpp - 1;
- }
- if (win.ws_col != 0)
- global_ctl->Mcol = win.ws_col;
- }
- signal(SIGWINCH, chgwinsz);
-}
-#endif /* SIGWINCH */
-
static void copy_file(FILE *f)
{
char buf[BUFSIZ];
@@ -1869,8 +1896,6 @@ static void display_file(struct more_control *ctl, FILE *f, char *initbuf, int l
ctl->context.line = ctl->context.chrctr = 0;
ctl->Currline = 0;
ctl->file_pos = 0;
- if (ctl->firstf)
- sigsetjmp(ctl->restore, 1);
if (ctl->firstf) {
ctl->firstf = 0;
if (ctl->srchopt) {
@@ -1881,10 +1906,8 @@ static void display_file(struct more_control *ctl, FILE *f, char *initbuf, int l
left--;
} else if (ctl->jumpopt)
skiplns(ctl, f);
- } else if (ctl->fnum < ctl->nfiles && !ctl->no_tty) {
- sigsetjmp(ctl->restore, 1);
+ } else if (ctl->fnum < ctl->nfiles && !ctl->no_tty)
left = command(ctl, ctl->fnames[ctl->fnum], f);
- }
if (left != 0) {
if ((ctl->noscroll || ctl->clearfirst)
&& (ctl->file_size != LONG_MAX)) {
@@ -1919,7 +1942,6 @@ static void display_file(struct more_control *ctl, FILE *f, char *initbuf, int l
ctl->within = 0;
}
}
- sigsetjmp(ctl->restore, 1);
fflush(stdout);
fclose(f);
ctl->screen_start.line = ctl->screen_start.chrctr = 0L;
@@ -1933,11 +1955,11 @@ int main(int argc, char **argv)
int c;
int left;
char *initbuf = NULL;
+ sigset_t sigset;
struct more_control ctl = {
.firstf = 1,
.fold_opt = 1,
.notell = 1,
- .startup = 1,
.stop_opt = 1,
.ul_opt = 1,
.Wrap = 1,
@@ -1946,7 +1968,6 @@ int main(int argc, char **argv)
.nscroll = SCROLL_LEN,
0
};
- global_ctl = &ctl;
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
@@ -2007,18 +2028,17 @@ int main(int argc, char **argv)
ctl.prnames = 1;
if (!ctl.no_intty && ctl.nfiles == 0)
usage(stderr);
- if (!ctl.no_tty) {
- signal(SIGQUIT, onquit);
- signal(SIGINT, end_it);
+ if (!ctl.no_tty)
+ tcsetattr(STDERR_FILENO, TCSANOW, &ctl.otty);
+ sigemptyset(&sigset);
+ sigaddset(&sigset, SIGINT);
+ sigaddset(&sigset, SIGQUIT);
+ sigaddset(&sigset, SIGTSTP);
#ifdef SIGWINCH
- signal(SIGWINCH, chgwinsz);
+ sigaddset(&sigset, SIGWINCH);
#endif
- if (signal(SIGTSTP, SIG_IGN) == SIG_DFL) {
- signal(SIGTSTP, onsusp);
- ctl.catch_susp = 1;
- }
- tcsetattr(STDERR_FILENO, TCSANOW, &ctl.otty);
- }
+ sigprocmask(SIG_BLOCK, &sigset, NULL);
+ ctl.sigfd = signalfd(-1, &sigset, SFD_CLOEXEC);
if (ctl.no_intty) {
if (ctl.no_tty)
copy_file(stdin);
--
2.3.0
--
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