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Diffstat (limited to 'coreutils/cal.c')
| -rw-r--r-- | coreutils/cal.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/coreutils/cal.c b/coreutils/cal.c new file mode 100644 index 0000000..9b59777 --- /dev/null +++ b/coreutils/cal.c @@ -0,0 +1,349 @@ +/* vi: set sw=4 ts=4: */ +/* + * Calendar implementation for busybox + * + * See original copyright at the end of this file + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ + +/* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */ +/* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect. The upstream + * BB_AUDIT BUG: version in util-linux seems to be broken as well. */ +/* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */ + +/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org) + * + * Major size reduction... over 50% (>1.5k) on i386. + */ + +#include "libbb.h" + +/* We often use "unsigned" intead of "int", it's easier to div on most CPUs */ + +#define THURSDAY 4 /* for reformation */ +#define SATURDAY 6 /* 1 Jan 1 was a Saturday */ + +#define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */ +#define NUMBER_MISSING_DAYS 11 /* 11 day correction */ + +#define MAXDAYS 42 /* max slots in a month array */ +#define SPACE -1 /* used in day array */ + +static const unsigned char days_in_month[] ALIGN1 = { + 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 +}; + +static const unsigned char sep1752[] ALIGN1 = { + 1, 2, 14, 15, 16, + 17, 18, 19, 20, 21, 22, 23, + 24, 25, 26, 27, 28, 29, 30 +}; + +/* Set to 0 or 1 in main */ +#define julian ((unsigned)option_mask32) + +/* leap year -- account for Gregorian reformation in 1752 */ +static int leap_year(unsigned yr) +{ + if (yr <= 1752) + return !(yr % 4); + return (!(yr % 4) && (yr % 100)) || !(yr % 400); +} + +/* number of centuries since 1700, not inclusive */ +#define centuries_since_1700(yr) \ + ((yr) > 1700 ? (yr) / 100 - 17 : 0) + +/* number of centuries since 1700 whose modulo of 400 is 0 */ +#define quad_centuries_since_1700(yr) \ + ((yr) > 1600 ? ((yr) - 1600) / 400 : 0) + +/* number of leap years between year 1 and this year, not inclusive */ +#define leap_years_since_year_1(yr) \ + ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) + +static void center(char *, unsigned, unsigned); +static void day_array(unsigned, unsigned, unsigned *); +static void trim_trailing_spaces_and_print(char *); + +static void blank_string(char *buf, size_t buflen); +static char *build_row(char *p, unsigned *dp); + +#define DAY_LEN 3 /* 3 spaces per day */ +#define J_DAY_LEN (DAY_LEN + 1) +#define WEEK_LEN 20 /* 7 * 3 - one space at the end */ +#define J_WEEK_LEN (WEEK_LEN + 7) +#define HEAD_SEP 2 /* spaces between day headings */ + +int cal_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int cal_main(int argc, char **argv) +{ + struct tm *local_time; + struct tm zero_tm; + time_t now; + unsigned month, year, flags, i; + char *month_names[12]; + char day_headings[28]; /* 28 for julian, 21 for nonjulian */ + char buf[40]; + + flags = getopt32(argv, "jy"); + /* This sets julian = flags & 1: */ + option_mask32 &= 1; + month = 0; + argv += optind; + argc -= optind; + + if (argc > 2) { + bb_show_usage(); + } + + if (!argc) { + time(&now); + local_time = localtime(&now); + year = local_time->tm_year + 1900; + if (!(flags & 2)) { /* no -y */ + month = local_time->tm_mon + 1; + } + } else { + if (argc == 2) { + month = xatou_range(*argv++, 1, 12); + } + year = xatou_range(*argv, 1, 9999); + } + + blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian); + + i = 0; + do { + zero_tm.tm_mon = i; + strftime(buf, sizeof(buf), "%B", &zero_tm); + month_names[i] = xstrdup(buf); + + if (i < 7) { + zero_tm.tm_wday = i; + strftime(buf, sizeof(buf), "%a", &zero_tm); + strncpy(day_headings + i * (3+julian) + julian, buf, 2); + } + } while (++i < 12); + + if (month) { + unsigned row, len, days[MAXDAYS]; + unsigned *dp = days; + char lineout[30]; + + day_array(month, year, dp); + len = sprintf(lineout, "%s %d", month_names[month - 1], year); + printf("%*s%s\n%s\n", + ((7*julian + WEEK_LEN) - len) / 2, "", + lineout, day_headings); + for (row = 0; row < 6; row++) { + build_row(lineout, dp)[0] = '\0'; + dp += 7; + trim_trailing_spaces_and_print(lineout); + } + } else { + unsigned row, which_cal, week_len, days[12][MAXDAYS]; + unsigned *dp; + char lineout[80]; + + sprintf(lineout, "%d", year); + center(lineout, + (WEEK_LEN * 3 + HEAD_SEP * 2) + + julian * (J_WEEK_LEN * 2 + HEAD_SEP + - (WEEK_LEN * 3 + HEAD_SEP * 2)), + 0); + puts("\n"); /* two \n's */ + for (i = 0; i < 12; i++) { + day_array(i + 1, year, days[i]); + } + blank_string(lineout, sizeof(lineout)); + week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN); + for (month = 0; month < 12; month += 3-julian) { + center(month_names[month], week_len, HEAD_SEP); + if (!julian) { + center(month_names[month + 1], week_len, HEAD_SEP); + } + center(month_names[month + 2 - julian], week_len, 0); + printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings); + if (!julian) { + printf("%*s%s", HEAD_SEP, "", day_headings); + } + bb_putchar('\n'); + for (row = 0; row < (6*7); row += 7) { + for (which_cal = 0; which_cal < 3-julian; which_cal++) { + dp = days[month + which_cal] + row; + build_row(lineout + which_cal * (week_len + 2), dp); + } + /* blank_string took care of nul termination. */ + trim_trailing_spaces_and_print(lineout); + } + } + } + + fflush_stdout_and_exit(EXIT_SUCCESS); +} + +/* + * day_array -- + * Fill in an array of 42 integers with a calendar. Assume for a moment + * that you took the (maximum) 6 rows in a calendar and stretched them + * out end to end. You would have 42 numbers or spaces. This routine + * builds that array for any month from Jan. 1 through Dec. 9999. + */ +static void day_array(unsigned month, unsigned year, unsigned *days) +{ + unsigned long temp; + unsigned i; + unsigned day, dw, dm; + + memset(days, SPACE, MAXDAYS * sizeof(int)); + + if ((month == 9) && (year == 1752)) { + /* Assumes the Gregorian reformation eliminates + * 3 Sep. 1752 through 13 Sep. 1752. + */ + unsigned j_offset = julian * 244; + size_t oday = 0; + + do { + days[oday+2] = sep1752[oday] + j_offset; + } while (++oday < sizeof(sep1752)); + + return; + } + + /* day_in_year + * return the 1 based day number within the year + */ + day = 1; + if ((month > 2) && leap_year(year)) { + ++day; + } + + i = month; + while (i) { + day += days_in_month[--i]; + } + + /* day_in_week + * return the 0 based day number for any date from 1 Jan. 1 to + * 31 Dec. 9999. Assumes the Gregorian reformation eliminates + * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all + * missing days. + */ + temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) + day; + if (temp < FIRST_MISSING_DAY) { + dw = ((temp - 1 + SATURDAY) % 7); + } else { + dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); + } + + if (!julian) { + day = 1; + } + + dm = days_in_month[month]; + if ((month == 2) && leap_year(year)) { + ++dm; + } + + do { + days[dw++] = day++; + } while (--dm); +} + +static void trim_trailing_spaces_and_print(char *s) +{ + char *p = s; + + while (*p) { + ++p; + } + while (p != s) { + --p; + if (!(isspace)(*p)) { /* We want the function... not the inline. */ + p[1] = '\0'; + break; + } + } + + puts(s); +} + +static void center(char *str, unsigned len, unsigned separate) +{ + unsigned n = strlen(str); + len -= n; + printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, ""); +} + +static void blank_string(char *buf, size_t buflen) +{ + memset(buf, ' ', buflen); + buf[buflen-1] = '\0'; +} + +static char *build_row(char *p, unsigned *dp) +{ + unsigned col, val, day; + + memset(p, ' ', (julian + DAY_LEN) * 7); + + col = 0; + do { + day = *dp++; + if (day != SPACE) { + if (julian) { + ++p; + if (day >= 100) { + *p = '0'; + p[-1] = (day / 100) + '0'; + day %= 100; + } + } + val = day / 10; + if (val > 0) { + *p = val + '0'; + } + *++p = day % 10 + '0'; + p += 2; + } else { + p += DAY_LEN + julian; + } + } while (++col < 7); + + return p; +} + +/* + * Copyright (c) 1989, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Kim Letkeman. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ |