From: Denis Vlasenko Date: Thu, 26 Jul 2007 11:12:51 +0000 (-0000) Subject: cal: small code shrink X-Git-Tag: android-x86-2.2~2703 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=661f6fad77b672a5f6648b01275eb9ff19c59139;p=android-x86%2Fexternal-busybox.git cal: small code shrink --- diff --git a/coreutils/cal.c b/coreutils/cal.c index ce910bc63..f8fc0b0d3 100644 --- a/coreutils/cal.c +++ b/coreutils/cal.c @@ -19,6 +19,8 @@ #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 */ @@ -28,29 +30,25 @@ #define MAXDAYS 42 /* max slots in a month array */ #define SPACE -1 /* used in day array */ -static const char days_in_month[] = { +static const unsigned char days_in_month[] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; -static const char sep1752[] = { +static const unsigned char sep1752[] = { 1, 2, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 }; -static int julian; +static unsigned julian; /* leap year -- account for Gregorian reformation in 1752 */ -#define leap_year(yr) \ - ((yr) <= 1752 ? !((yr) % 4) : \ - (!((yr) % 4) && ((yr) % 100)) || !((yr) % 400)) - -static int is_leap_year(int year) +static int leap_year(unsigned yr) { - return leap_year(year); + if (yr <= 1752) + return !(yr % 4); + return (!(yr % 4) && (yr % 100)) || !(yr % 400); } -#undef leap_year -#define leap_year(yr) is_leap_year(yr) /* number of centuries since 1700, not inclusive */ #define centuries_since_1700(yr) \ @@ -64,12 +62,12 @@ static int is_leap_year(int year) #define leap_years_since_year_1(yr) \ ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) -static void center (char *, int, int); -static void day_array (int, int, int *); -static void trim_trailing_spaces_and_print (char *); +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, int *dp); +static char *build_row(char *p, unsigned *dp); #define DAY_LEN 3 /* 3 spaces per day */ #define J_DAY_LEN (DAY_LEN + 1) @@ -83,20 +81,18 @@ int cal_main(int argc, char **argv) struct tm *local_time; struct tm zero_tm; time_t now; - int month, year, flags, i; + unsigned month, year, flags, i; char *month_names[12]; char day_headings[28]; /* 28 for julian, 21 for nonjulian */ char buf[40]; flags = getopt32(argc, argv, "jy"); - julian = flags & 1; - - argv += optind; - month = 0; + argv += optind; + argc -= optind; - if ((argc -= optind) > 2) { + if (argc > 2) { bb_show_usage(); } @@ -109,12 +105,12 @@ int cal_main(int argc, char **argv) } } else { if (argc == 2) { - month = xatoul_range(*argv++, 1, 12); + month = xatou_range(*argv++, 1, 12); } - year = xatoul_range(*argv, 1, 9999); + year = xatou_range(*argv, 1, 9999); } - blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian); + blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian); i = 0; do { @@ -130,8 +126,8 @@ int cal_main(int argc, char **argv) } while (++i < 12); if (month) { - int row, len, days[MAXDAYS]; - int *dp = days; + unsigned row, len, days[MAXDAYS]; + unsigned *dp = days; char lineout[30]; day_array(month, year, dp); @@ -145,8 +141,8 @@ int cal_main(int argc, char **argv) trim_trailing_spaces_and_print(lineout); } } else { - int row, which_cal, week_len, days[12][MAXDAYS]; - int *dp; + unsigned row, which_cal, week_len, days[12][MAXDAYS]; + unsigned *dp; char lineout[80]; sprintf(lineout, "%d", year); @@ -193,19 +189,21 @@ int cal_main(int argc, char **argv) * 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(int month, int year, int *days) +static void day_array(unsigned month, unsigned year, unsigned *days) { - long temp; - int i; - int j_offset; - int day, dw, dm; + 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; - j_offset = julian * 244; do { days[oday+2] = sep1752[oday] + j_offset; } while (++oday < sizeof(sep1752)); @@ -214,7 +212,7 @@ static void day_array(int month, int year, int *days) } /* day_in_year - * return the 1 based day number within the year + * return the 1 based day number within the year */ day = 1; if ((month > 2) && leap_year(year)) { @@ -227,17 +225,15 @@ static void day_array(int month, int year, int *days) } /* 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. + * 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. */ - dw = THURSDAY; - temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) - + day; + temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) + day; if (temp < FIRST_MISSING_DAY) { dw = ((temp - 1 + SATURDAY) % 7); - } else if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) { + } else { dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); } @@ -250,10 +246,9 @@ static void day_array(int month, int year, int *days) ++dm; } - while (dm) { + do { days[dw++] = day++; - --dm; - } + } while (--dm); } static void trim_trailing_spaces_and_print(char *s) @@ -263,7 +258,7 @@ static void trim_trailing_spaces_and_print(char *s) while (*p) { ++p; } - while (p > s) { + while (p != s) { --p; if (!(isspace)(*p)) { /* We want the function... not the inline. */ p[1] = '\0'; @@ -274,9 +269,9 @@ static void trim_trailing_spaces_and_print(char *s) puts(s); } -static void center(char *str, int len, int separate) +static void center(char *str, unsigned len, unsigned separate) { - int n = strlen(str); + unsigned n = strlen(str); len -= n; printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, ""); } @@ -287,15 +282,16 @@ static void blank_string(char *buf, size_t buflen) buf[buflen-1] = '\0'; } -static char *build_row(char *p, int *dp) +static char *build_row(char *p, unsigned *dp) { - int col, val, day; + unsigned col, val, day; memset(p, ' ', (julian + DAY_LEN) * 7); col = 0; do { - if ((day = *dp++) != SPACE) { + day = *dp++; + if (day != SPACE) { if (julian) { ++p; if (day >= 100) { @@ -304,7 +300,8 @@ static char *build_row(char *p, int *dp) day %= 100; } } - if ((val = day / 10) > 0) { + val = day / 10; + if (val > 0) { *p = val + '0'; } *++p = day % 10 + '0'; @@ -348,5 +345,3 @@ static char *build_row(char *p, int *dp) * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ - -