diff options
| -rw-r--r-- | include/libbb.h | 29 | ||||
| -rw-r--r-- | miscutils/less.c | 99 |
2 files changed, 82 insertions, 46 deletions
diff --git a/include/libbb.h b/include/libbb.h index eb8b2f620..873ab8798 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -274,9 +274,32 @@ char *xrealloc_getcwd_or_warn(char *cwd); char *xmalloc_follow_symlinks(const char *path); -//enum { -// BB_SIGS_FATAL = , -//}; +enum { + /* bb_signals(BB_SIGS_FATAL, handler) catches all signals which + * otherwise would kill us, except for those resulting from bugs: + * SIGSEGV, SIGILL, SIGFPE. + * Other fatal signals not included (TODO?): + * SIGBUS Bus error (bad memory access) + * SIGPOLL Pollable event. Synonym of SIGIO + * SIGPROF Profiling timer expired + * SIGSYS Bad argument to routine + * SIGTRAP Trace/breakpoint trap + */ + BB_SIGS_FATAL = 0 + + (1 << SIGHUP) + + (1 << SIGINT) + + (1 << SIGTERM) + + (1 << SIGPIPE) // Write to pipe with no readers + + (1 << SIGQUIT) // Quit from keyboard + + (1 << SIGABRT) // Abort signal from abort(3) + + (1 << SIGALRM) // Timer signal from alarm(2) + + (1 << SIGVTALRM) // Virtual alarm clock + + (1 << SIGXCPU) // CPU time limit exceeded + + (1 << SIGXFSZ) // File size limit exceeded + + (1 << SIGUSR1) // Yes kids, these are also fatal! + + (1 << SIGUSR2) + + 0, +}; void bb_signals(int sigs, void (*f)(int)); /* Unlike signal() and bb_signals, sets handler with sigaction() * and in a way that while signal handler is run, no other signals diff --git a/miscutils/less.c b/miscutils/less.c index 85c5ec536..4229dfe15 100644 --- a/miscutils/less.c +++ b/miscutils/less.c @@ -90,6 +90,7 @@ enum { pattern_valid = 0 }; struct globals { int cur_fline; /* signed */ int kbd_fd; /* fd to get input from */ + int less_gets_pos; /* last position in last line, taking into account tabs */ size_t linepos; unsigned max_displayed_line; @@ -123,6 +124,7 @@ struct globals { #define G (*ptr_to_globals) #define cur_fline (G.cur_fline ) #define kbd_fd (G.kbd_fd ) +#define less_gets_pos (G.less_gets_pos ) #define linepos (G.linepos ) #define max_displayed_line (G.max_displayed_line) #define max_fline (G.max_fline ) @@ -152,6 +154,7 @@ struct globals { #define term_less (G.term_less ) #define INIT_G() do { \ PTR_TO_GLOBALS = xzalloc(sizeof(G)); \ + less_gets_pos = -1; \ empty_line_marker = "~"; \ num_files = 1; \ current_file = 1; \ @@ -385,6 +388,9 @@ static void m_status_print(void) { int percentage; + if (less_gets_pos >= 0) /* don't touch statusline while input is done! */ + return; + clear_line(); printf(HIGHLIGHT"%s", filename); if (num_files > 1) @@ -408,6 +414,9 @@ static void status_print(void) { const char *p; + if (less_gets_pos >= 0) /* don't touch statusline while input is done! */ + return; + /* Change the status if flags have been set */ #if ENABLE_FEATURE_LESS_FLAGS if (option_mask32 & (FLAG_M|FLAG_m)) { @@ -652,43 +661,46 @@ static void reinitialize(void) buffer_fill_and_print(); } -static void getch_nowait(char* input, int sz) +static ssize_t getch_nowait(char* input, int sz) { ssize_t rd; - fd_set readfds; - again: - fflush(stdout); + struct pollfd pfd[2]; - /* NB: select returns whenever read will not block. Therefore: - * (a) with O_NONBLOCK'ed fds select will return immediately - * (b) if eof is reached, select will also return - * because read will immediately return 0 bytes. - * Even if select says that input is available, read CAN block + pfd[0].fd = STDIN_FILENO; + pfd[0].events = POLLIN; + pfd[1].fd = kbd_fd; + pfd[1].events = POLLIN; + again: + tcsetattr(kbd_fd, TCSANOW, &term_less); + /* NB: select/poll returns whenever read will not block. Therefore: + * if eof is reached, select/poll will return immediately + * because read will immediately return 0 bytes. + * Even if select/poll says that input is available, read CAN block * (switch fd into O_NONBLOCK'ed mode to avoid it) */ - FD_ZERO(&readfds); + rd = 1; if (max_fline <= cur_fline + max_displayed_line && eof_error > 0 /* did NOT reach eof yet */ ) { /* We are interested in stdin */ - FD_SET(0, &readfds); + rd = 0; } - FD_SET(kbd_fd, &readfds); - tcsetattr(kbd_fd, TCSANOW, &term_less); - select(kbd_fd + 1, &readfds, NULL, NULL, NULL); + /* position cursor if line input is done */ + if (less_gets_pos >= 0) + move_cursor(max_displayed_line + 2, less_gets_pos + 1); + fflush(stdout); + safe_poll(pfd + rd, 2 - rd, -1); input[0] = '\0'; - ndelay_on(kbd_fd); - rd = read(kbd_fd, input, sz); - ndelay_off(kbd_fd); - if (rd < 0) { - /* No keyboard input, but we have input on stdin! */ - if (errno != EAGAIN) /* Huh?? */ - return; + rd = safe_read(kbd_fd, input, sz); /* NB: kbd_fd is in O_NONBLOCK mode */ + if (rd < 0 && errno == EAGAIN) { + /* No keyboard input -> we have input on stdin! */ read_lines(); buffer_fill_and_print(); goto again; } + set_tty_cooked(); + return rd; } /* Grab a character from input without requiring the return key. If the @@ -696,7 +708,7 @@ static void getch_nowait(char* input, int sz) * special return codes. Note that this function works best with raw input. */ static int less_getch(void) { - char input[16]; + unsigned char input[16]; unsigned i; again: memset(input, 0, sizeof(input)); @@ -705,7 +717,6 @@ static int less_getch(void) /* Detect escape sequences (i.e. arrow keys) and handle * them accordingly */ if (input[0] == '\033' && input[1] == '[') { - set_tty_cooked(); i = input[2] - REAL_KEY_UP; if (i < 4) return 20 + i; @@ -724,8 +735,8 @@ static int less_getch(void) } /* Reject almost all control chars */ i = input[0]; - if (i < ' ' && i != 0x0d && i != 8) goto again; - set_tty_cooked(); + if (i < ' ' && i != 0x0d && i != 8) + goto again; return i; } @@ -734,22 +745,21 @@ static char* less_gets(int sz) char c; int i = 0; char *result = xzalloc(1); - while (1) { - fflush(stdout); - - /* I be damned if I know why is it needed *repeatedly*, - * but it is needed. Is it because of stdio? */ - tcsetattr(kbd_fd, TCSANOW, &term_less); + while (1) { c = '\0'; - read(kbd_fd, &c, 1); - if (c == 0x0d) + less_gets_pos = sz + i; + getch_nowait(&c, 1); + if (c == 0x0d) { + less_gets_pos = -1; return result; + } if (c == 0x7f) c = 8; if (c == 8 && i) { printf("\x8 \x8"); i--; + result[i] = '\0'; } if (c < ' ') continue; @@ -764,9 +774,17 @@ static char* less_gets(int sz) static void examine_file(void) { + char *new_fname; + print_statusline("Examine: "); + new_fname = less_gets(sizeof("Examine: ")-1); + if (!new_fname[0]) { + free(new_fname); + status_print(); + return; + } free(filename); - filename = less_gets(sizeof("Examine: ")-1); + filename = new_fname; /* files start by = argv. why we assume that argv is infinitely long?? files[num_files] = filename; current_file = num_files + 1; @@ -1087,7 +1105,7 @@ static void save_input_to_file(void) print_statusline("Log file: "); current_line = less_gets(sizeof("Log file: ")-1); - if (strlen(current_line) > 0) { + if (current_line[0]) { fp = fopen(current_line, "w"); if (!fp) { msg = "Error opening log file"; @@ -1334,6 +1352,7 @@ int less_main(int argc, char **argv) kbd_fd = open(CURRENT_TTY, O_RDONLY); if (kbd_fd < 0) return bb_cat(argv); + ndelay_on(kbd_fd); if (!num_files) { if (isatty(STDIN_FILENO)) { @@ -1354,11 +1373,9 @@ int less_main(int argc, char **argv) if (option_mask32 & FLAG_TILDE) empty_line_marker = ""; + bb_signals(BB_SIGS_FATAL, sig_catcher); + tcgetattr(kbd_fd, &term_orig); - bb_signals(0 - + (1 << SIGTERM) - + (1 << SIGINT) - , sig_catcher); term_less = term_orig; term_less.c_lflag &= ~(ICANON | ECHO); term_less.c_iflag &= ~(IXON | ICRNL); @@ -1366,10 +1383,6 @@ int less_main(int argc, char **argv) term_less.c_cc[VMIN] = 1; term_less.c_cc[VTIME] = 0; - /* Want to do it just once, but it doesn't work, */ - /* so we are redoing it (see code above). Mystery... */ - /*tcsetattr(kbd_fd, TCSANOW, &term_less);*/ - reinitialize(); while (1) { keypress = less_getch(); |