/* * watch -- execute a program repeatedly, displaying output fullscreen * * Based on the original 1991 'watch' by Tony Rems * (with mods and corrections by Francois Pinard). * * Substantially reworked, new features (differences option, SIGWINCH * handling, unlimited command length, long line handling) added Apr * 1999 by Mike Coleman . * * Changes by Albert Cahalan, 2002-2003. * stderr handling, exec, and beep option added by Morty Abzug, 2008 * Unicode Support added by Jarrod Lowe in 2009. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "c.h" #include "config.h" #include "fileutils.h" #include "nls.h" #include "strutils.h" #include "xalloc.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef WITH_WATCH8BIT # include # include # include #else # include #endif /* WITH_WATCH8BIT */ #ifdef FORCE_8BIT # undef isprint # define isprint(x) ( (x>=' '&&x<='~') || (x>=0xa0) ) #endif /* Boolean command line options */ static int flags; #define WATCH_DIFF (1 << 1) #define WATCH_CUMUL (1 << 2) #define WATCH_EXEC (1 << 3) #define WATCH_BEEP (1 << 4) #define WATCH_COLOR (1 << 5) #define WATCH_ERREXIT (1 << 6) #define WATCH_CHGEXIT (1 << 7) static int curses_started = 0; static long height = 24, width = 80; static int screen_size_changed = 0; static int first_screen = 1; static int show_title = 2; /* number of lines used, 2 or 0 */ static int precise_timekeeping = 0; #define min(x,y) ((x) > (y) ? (y) : (x)) #define MAX_ANSIBUF 100 static void __attribute__ ((__noreturn__)) usage(FILE * out) { fputs(USAGE_HEADER, out); fprintf(out, _(" %s [options] command\n"), program_invocation_short_name); fputs(USAGE_OPTIONS, out); fputs(_(" -b, --beep beep if command has a non-zero exit\n"), out); fputs(_(" -c, --color interpret ANSI color and style sequences\n"), out); fputs(_(" -d, --differences[=]\n" " highlight changes between updates\n"), out); fputs(_(" -e, --errexit exit if command has a non-zero exit\n"), out); fputs(_(" -g, --chgexit exit when output from command changes\n"), out); fputs(_(" -n, --interval seconds to wait between updates\n"), out); fputs(_(" -p, --precise attempt run command in precise intervals\n"), out); fputs(_(" -t, --no-title turn off header\n"), out); fputs(_(" -x, --exec pass command to exec instead of \"sh -c\"\n"), out); fputs(USAGE_SEPARATOR, out); fputs(USAGE_HELP, out); fputs(_(" -v, --version output version information and exit\n"), out); fprintf(out, USAGE_MAN_TAIL("watch(1)")); exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS); } static int nr_of_colors; static int attributes; static int fg_col; static int bg_col; static void init_ansi_colors(void) { short ncurses_colors[] = { COLOR_BLACK, COLOR_RED, COLOR_GREEN, COLOR_YELLOW, COLOR_BLUE, COLOR_MAGENTA, COLOR_CYAN, COLOR_WHITE }; nr_of_colors = sizeof(ncurses_colors) / sizeof(short); for (bg_col = 0; bg_col < nr_of_colors; bg_col++) for (fg_col = 0; fg_col < nr_of_colors; fg_col++) init_pair(bg_col * nr_of_colors + fg_col + 1, ncurses_colors[fg_col], ncurses_colors[bg_col]); /* default settings */ attributes = A_NORMAL; fg_col = COLOR_WHITE; bg_col = COLOR_BLACK; } static void set_ansi_attribute(const int attrib) { switch (attrib) { case -1: /* restore last settings */ break; case 0: /* restore default settings */ attributes = A_NORMAL; fg_col = COLOR_WHITE; bg_col = COLOR_BLACK; break; case 1: /* set bold / increased intensity */ attributes |= A_BOLD; break; case 2: /* set decreased intensity (if supported) */ attributes |= A_DIM; break; #ifdef A_ITALIC case 3: /* set italic (if supported) */ attributes |= A_ITALIC; break; #endif case 4: /* set underline */ attributes |= A_UNDERLINE; break; case 5: /* set blinking */ attributes |= A_BLINK; break; case 7: /* set inversed */ attributes |= A_REVERSE; break; case 21: /* unset bold / increased intensity */ attributes &= ~A_BOLD; break; case 22: /* unset bold / any intensity modifier */ attributes &= ~(A_BOLD | A_DIM); break; #ifdef A_ITALIC case 23: /* unset italic */ attributes &= A_ITALIC; break; #endif case 24: /* unset underline */ attributes &= ~A_UNDERLINE; break; case 25: /* unset blinking */ attributes &= ~A_BLINK; break; case 27: /* unset inversed */ attributes &= ~A_REVERSE; break; default: if (attrib >= 30 && attrib <= 37) { /* set foreground color */ fg_col = attrib - 30; } else if (attrib >= 40 && attrib <= 47) { /* set background color */ bg_col = attrib - 40; } } attrset(attributes | COLOR_PAIR(bg_col * nr_of_colors + fg_col + 1)); } static void process_ansi(FILE * fp) { int i, c; char buf[MAX_ANSIBUF]; char *numstart, *endptr; c = getc(fp); if (c != '[') { ungetc(c, fp); return; } for (i = 0; i < MAX_ANSIBUF; i++) { c = getc(fp); /* COLOUR SEQUENCE ENDS in 'm' */ if (c == 'm') { buf[i] = '\0'; break; } if (c < '0' && c > '9' && c != ';') { while (--i >= 0) ungetc(buf[i], fp); return; } buf[i] = (char)c; } /* * buf now contains a semicolon-separated list of decimal integers, * each indicating an attribute to apply. * For example, buf might contain "0;1;31", derived from the color * escape sequence "[0;1;31m". There can be 1 or more * attributes to apply, but typically there are between 1 and 3. */ for (endptr = numstart = buf; *endptr != '\0'; numstart = endptr + 1) set_ansi_attribute(strtol(numstart, &endptr, 10)); } static void __attribute__ ((__noreturn__)) do_exit(int status) { if (curses_started) endwin(); exit(status); } /* signal handler */ static void die(int notused __attribute__ ((__unused__))) { do_exit(EXIT_SUCCESS); } static void winch_handler(int notused __attribute__ ((__unused__))) { screen_size_changed = 1; } static char env_col_buf[24]; static char env_row_buf[24]; static int incoming_cols; static int incoming_rows; static void get_terminal_size(void) { struct winsize w; if (!incoming_cols) { /* have we checked COLUMNS? */ const char *s = getenv("COLUMNS"); incoming_cols = -1; if (s && *s) { long t; char *endptr; t = strtol(s, &endptr, 0); if (!*endptr && 0 < t) incoming_cols = t; width = incoming_cols; snprintf(env_col_buf, sizeof env_col_buf, "COLUMNS=%ld", width); putenv(env_col_buf); } } if (!incoming_rows) { /* have we checked LINES? */ const char *s = getenv("LINES"); incoming_rows = -1; if (s && *s) { long t; char *endptr; t = strtol(s, &endptr, 0); if (!*endptr && 0 < t) incoming_rows = t; height = incoming_rows; snprintf(env_row_buf, sizeof env_row_buf, "LINES=%ld", height); putenv(env_row_buf); } } if (ioctl(STDERR_FILENO, TIOCGWINSZ, &w) == 0) { if (incoming_cols < 0 || incoming_rows < 0) { if (incoming_rows < 0 && w.ws_row > 0) { height = w.ws_row; snprintf(env_row_buf, sizeof env_row_buf, "LINES=%ld", height); putenv(env_row_buf); } if (incoming_cols < 0 && w.ws_col > 0) { width = w.ws_col; snprintf(env_col_buf, sizeof env_col_buf, "COLUMNS=%ld", width); putenv(env_col_buf); } } } } /* get current time in usec */ typedef unsigned long long watch_usec_t; #define USECS_PER_SEC (1000000ull) static watch_usec_t get_time_usec() { struct timeval now; gettimeofday(&now, NULL); return USECS_PER_SEC * now.tv_sec + now.tv_usec; } #ifdef WITH_WATCH8BIT /* read a wide character from a popen'd stream */ #define MAX_ENC_BYTES 16 wint_t my_getwc(FILE * s); wint_t my_getwc(FILE * s) { /* assuming no encoding ever consumes more than 16 bytes */ char i[MAX_ENC_BYTES]; int byte = 0; int convert; int x; wchar_t rval; while (1) { i[byte] = getc(s); if (i[byte] == EOF) { return WEOF; } byte++; errno = 0; mbtowc(NULL, NULL, 0); convert = mbtowc(&rval, i, byte); x = errno; if (convert > 0) { /* legal conversion */ return rval; } if (byte == MAX_ENC_BYTES) { while (byte > 1) { /* at least *try* to fix up */ ungetc(i[--byte], s); } errno = -EILSEQ; return WEOF; } } } #endif /* WITH_WATCH8BIT */ #ifdef WITH_WATCH8BIT static void output_header(wchar_t *restrict wcommand, int wcommand_columns, int wcommand_characters, double interval) #else static void output_header(char *restrict command, double interval) #endif /* WITH_WATCH8BIT */ { time_t t = time(NULL); char *ts = ctime(&t); int tsl = strlen(ts); char *header; /* * left justify interval and command, right justify time, * clipping all to fit window width */ int hlen = asprintf(&header, _("Every %.1fs: "), interval); /* * the rules: * width < tsl : print nothing * width < tsl + hlen + 1: print ts * width = tsl + hlen + 1: print header, ts * width < tsl + hlen + 4: print header, ..., ts * width < tsl + hlen + wcommand_columns: print header, * truncated wcommand, ..., ts * width > "": print header, wcomand, ts * this is slightly different from how it used to be */ if (width < tsl) { free(header); return; } if (tsl + hlen + 1 <= width) { mvaddstr(0, 0, header); if (tsl + hlen + 2 <= width) { if (width < tsl + hlen + 4) { mvaddstr(0, width - tsl - 4, "... "); } else { #ifdef WITH_WATCH8BIT if (width < tsl + hlen + wcommand_columns) { /* print truncated */ int available = width - tsl - hlen; int in_use = wcommand_columns; int wcomm_len = wcommand_characters; while (available - 4 < in_use) { wcomm_len--; in_use = wcswidth(wcommand, wcomm_len); } mvaddnwstr(0, hlen, wcommand, wcomm_len); mvaddstr(0, width - tsl - 4, "... "); } else { mvaddwstr(0, hlen, wcommand); } #else mvaddnstr(0, hlen, command, width - tsl - hlen); #endif /* WITH_WATCH8BIT */ } } } mvaddstr(0, width - tsl + 1, ts); free(header); return; } static int run_command(char *restrict command, char **restrict command_argv) { FILE *p; int x, y; int oldeolseen = 1; int pipefd[2]; pid_t child; int exit_early = 0; int status; /* allocate pipes */ if (pipe(pipefd) < 0) xerr(7, _("unable to create IPC pipes")); /* flush stdout and stderr, since we're about to do fd stuff */ fflush(stdout); fflush(stderr); /* fork to prepare to run command */ child = fork(); if (child < 0) { /* fork error */ xerr(2, _("unable to fork process")); } else if (child == 0) { /* in child */ close(pipefd[0]); /* child doesn't need read side of pipe */ close(1); /* prepare to replace stdout with pipe */ if (dup2(pipefd[1], 1) < 0) { /* replace stdout with write side of pipe */ xerr(3, _("dup2 failed")); } close(pipefd[1]); /* once duped, the write fd isn't needed */ dup2(1, 2); /* stderr should default to stdout */ if (flags & WATCH_EXEC) { /* pass command to exec instead of system */ if (execvp(command_argv[0], command_argv) == -1) { xerr(4, _("unable to execute '%s'"), command_argv[0]); } } else { status = system(command); /* watch manpage promises sh quoting */ /* propagate command exit status as child exit status */ if (!WIFEXITED(status)) { /* child exits nonzero if command does */ exit(EXIT_FAILURE); } else { exit(WEXITSTATUS(status)); } } } /* otherwise, we're in parent */ close(pipefd[1]); /* close write side of pipe */ if ((p = fdopen(pipefd[0], "r")) == NULL) xerr(5, _("fdopen")); for (y = show_title; y < height; y++) { int eolseen = 0, tabpending = 0, tabwaspending; set_ansi_attribute(-1); #ifdef WITH_WATCH8BIT wint_t carry = WEOF; #endif for (x = 0; x < width; x++) { #ifdef WITH_WATCH8BIT wint_t c = ' '; #else int c = ' '; #endif int attr = 0; if (tabwaspending && (flags & WATCH_COLOR)) set_ansi_attribute(-1); tabwaspending = 0; if (!eolseen) { /* if there is a tab pending, just * spit spaces until the next stop * instead of reading characters */ if (!tabpending) #ifdef WITH_WATCH8BIT do { if (carry == WEOF) { c = my_getwc(p); } else { c = carry; carry = WEOF; } } while (c != WEOF && !iswprint(c) && c < 128 && wcwidth(c) == 0 && c != L'\n' && c != L'\t' && (c != L'\033' || !(flags & WATCH_COLOR))); #else do c = getc(p); while (c != EOF && !isprint(c) && c != '\n' && c != '\t' && (c != L'\033' || !(flags & WATCH_COLOR))); #endif if (c == L'\033' && (flags & WATCH_COLOR)) { x--; process_ansi(p); continue; } if (c == L'\n') if (!oldeolseen && x == 0) { x = -1; continue; } else eolseen = 1; else if (c == L'\t') tabpending = 1; #ifdef WITH_WATCH8BIT if (x == width - 1 && wcwidth(c) == 2) { y++; x = -1; /* process this double-width */ carry = c; /* character on the next line */ continue; /* because it won't fit here */ } if (c == WEOF || c == L'\n' || c == L'\t') { c = L' '; if (flags & WATCH_COLOR) attrset(A_NORMAL); } #else if (c == EOF || c == '\n' || c == '\t') { c = ' '; if (flags & WATCH_COLOR) attrset(A_NORMAL); } #endif if (tabpending && (((x + 1) % 8) == 0)) { tabpending = 0; tabwaspending = 1; } } move(y, x); if (!first_screen && !exit_early && (flags & WATCH_CHGEXIT)) { #ifdef WITH_WATCH8BIT cchar_t oldc; in_wch(&oldc); exit_early = (wchar_t) c != oldc.chars[0]; #else chtype oldch = inch(); unsigned char oldc = oldch & A_CHARTEXT; exit_early = (unsigned char)c != oldc; #endif } if (flags & WATCH_DIFF) { #ifdef WITH_WATCH8BIT cchar_t oldc; in_wch(&oldc); attr = !first_screen && ((wchar_t) c != oldc.chars[0] || ((flags & WATCH_CUMUL) && (oldc.attr & A_ATTRIBUTES))); #else chtype oldch = inch(); unsigned char oldc = oldch & A_CHARTEXT; attr = !first_screen && ((unsigned char)c != oldc || ((flags & WATCH_CUMUL) && (oldch & A_ATTRIBUTES))); #endif } if (attr) standout(); #ifdef WITH_WATCH8BIT addnwstr((wchar_t *) & c, 1); #else addch(c); #endif if (attr) standend(); #ifdef WITH_WATCH8BIT if (wcwidth(c) == 0) { x--; } if (wcwidth(c) == 2) { x++; } #endif } oldeolseen = eolseen; } fclose(p); /* harvest child process and get status, propagated from command */ if (waitpid(child, &status, 0) < 0) xerr(8, _("waitpid")); /* if child process exited in error, beep if option_beep is set */ if ((!WIFEXITED(status) || WEXITSTATUS(status))) { if (flags & WATCH_BEEP) beep(); if (flags & WATCH_ERREXIT) { mvaddstr(height - 1, 0, _("command exit with a non-zero status, press a key to exit")); refresh(); fgetc(stdin); endwin(); exit(8); } } first_screen = 0; refresh(); return exit_early; } int main(int argc, char *argv[]) { int optc; double interval = 2; char *command; char **command_argv; int command_length = 0; /* not including final \0 */ watch_usec_t next_loop; /* next loop time in us, used for precise time * keeping only */ #ifdef WITH_WATCH8BIT wchar_t *wcommand = NULL; int wcommand_columns = 0; /* not including final \0 */ int wcommand_characters = 0; /* not including final \0 */ #endif /* WITH_WATCH8BIT */ static struct option longopts[] = { {"color", no_argument, 0, 'c'}, {"differences", optional_argument, 0, 'd'}, {"help", no_argument, 0, 'h'}, {"interval", required_argument, 0, 'n'}, {"beep", no_argument, 0, 'b'}, {"errexit", no_argument, 0, 'e'}, {"chgexit", no_argument, 0, 'g'}, {"exec", no_argument, 0, 'x'}, {"precise", no_argument, 0, 'p'}, {"no-title", no_argument, 0, 't'}, {"version", no_argument, 0, 'v'}, {0, 0, 0, 0} }; #ifdef HAVE_PROGRAM_INVOCATION_NAME program_invocation_name = program_invocation_short_name; #endif setlocale(LC_ALL, ""); bindtextdomain(PACKAGE, LOCALEDIR); textdomain(PACKAGE); atexit(close_stdout); while ((optc = getopt_long(argc, argv, "+bced::ghn:pvtx", longopts, (int *)0)) != EOF) { switch (optc) { case 'b': flags |= WATCH_BEEP; break; case 'c': flags |= WATCH_COLOR; break; case 'd': flags |= WATCH_DIFF; if (optarg) flags |= WATCH_CUMUL; break; case 'e': flags |= WATCH_ERREXIT; break; case 'g': flags |= WATCH_CHGEXIT; break; case 't': show_title = 0; break; case 'x': flags |= WATCH_EXEC; break; case 'n': interval = strtod_or_err(optarg, _("failed to parse argument")); if (interval < 0.1) interval = 0.1; if (interval > UINT_MAX) interval = UINT_MAX; break; case 'p': precise_timekeeping = 1; break; case 'h': usage(stdout); break; case 'v': printf(PROCPS_NG_VERSION); return EXIT_SUCCESS; default: usage(stderr); break; } } if (optind >= argc) usage(stderr); /* save for later */ command_argv = &(argv[optind]); command = xstrdup(argv[optind++]); command_length = strlen(command); for (; optind < argc; optind++) { char *endp; int s = strlen(argv[optind]); /* space and \0 */ command = xrealloc(command, command_length + s + 2); endp = command + command_length; *endp = ' '; memcpy(endp + 1, argv[optind], s); /* space then string length */ command_length += 1 + s; command[command_length] = '\0'; } #ifdef WITH_WATCH8BIT /* convert to wide for printing purposes */ /*mbstowcs(NULL, NULL, 0); */ wcommand_characters = mbstowcs(NULL, command, 0); if (wcommand_characters < 0) { fprintf(stderr, _("unicode handling error\n")); exit(EXIT_FAILURE); } wcommand = (wchar_t *) malloc((wcommand_characters + 1) * sizeof(wcommand)); if (wcommand == NULL) { fprintf(stderr, _("unicode handling error (malloc)\n")); exit(EXIT_FAILURE); } mbstowcs(wcommand, command, wcommand_characters + 1); wcommand_columns = wcswidth(wcommand, -1); #endif /* WITH_WATCH8BIT */ get_terminal_size(); /* Catch keyboard interrupts so we can put tty back in a sane * state. */ signal(SIGINT, die); signal(SIGTERM, die); signal(SIGHUP, die); signal(SIGWINCH, winch_handler); /* Set up tty for curses use. */ curses_started = 1; initscr(); if (flags & WATCH_COLOR) { if (has_colors()) { start_color(); use_default_colors(); init_ansi_colors(); } else { flags |= WATCH_COLOR; } } nonl(); noecho(); cbreak(); if (precise_timekeeping) next_loop = get_time_usec(); while (1) { if (screen_size_changed) { get_terminal_size(); resizeterm(height, width); clear(); /* redrawwin(stdscr); */ screen_size_changed = 0; first_screen = 1; } if (show_title) #ifdef WITH_WATCH8BIT output_header(wcommand, wcommand_columns, wcommand_characters, interval); #else output_header(command, interval); #endif /* WITH_WATCH8BIT */ if (run_command(command, command_argv)) break; if (precise_timekeeping) { watch_usec_t cur_time = get_time_usec(); next_loop += USECS_PER_SEC * interval; if (cur_time < next_loop) usleep(next_loop - cur_time); } else if (interval < UINT_MAX / USECS_PER_SEC) usleep(interval * USECS_PER_SEC); else sleep(interval); } endwin(); return EXIT_SUCCESS; }