From 89967023da94c0d874713284869e1924797d30bb Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 30 Apr 2005 13:19:56 -0700 Subject: [PATCH] Make the date parsing accept pretty much any random crap. This date parser turns line-noise into a date. Cool. --- Makefile | 3 + date.c | 321 +++++++++++++++++++++++++++++++++++----------------- test-date.c | 20 ++++ 3 files changed, 238 insertions(+), 106 deletions(-) create mode 100644 test-date.c diff --git a/Makefile b/Makefile index 783ad4d33..37d7192f6 100644 --- a/Makefile +++ b/Makefile @@ -60,6 +60,9 @@ CFLAGS += '-DSHA1_HEADER=$(SHA1_HEADER)' $(LIB_FILE): $(LIB_OBJS) $(AR) rcs $@ $(LIB_OBJS) +test-date: test-date.c date.o + $(CC) $(CFLAGS) -o $@ test-date.c date.o + git-%: %.c $(LIB_FILE) $(CC) $(CFLAGS) -o $@ $(filter %.c,$^) $(LIBS) diff --git a/date.c b/date.c index 1e43936f8..b59e832d6 100644 --- a/date.c +++ b/date.c @@ -30,144 +30,253 @@ static time_t my_mktime(struct tm *tm) } static const char *month_names[] = { - "Jan", "Feb", "Mar", "Apr", "May", "Jun", - "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" + "January", "February", "March", "April", "May", "June", + "July", "August", "September", "October", "November", "December" }; static const char *weekday_names[] = { - "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" + "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" }; +/* + * Check these. And note how it doesn't do the summer-time conversion. + * + * In my world, it's always summer, and things are probably a bit off + * in other ways too. + */ +static const struct { + const char *name; + int offset; +} timezone_names[] = { + { "IDLW", -12 }, /* International Date Line West */ + { "NT", -11 }, /* Nome */ + { "CAT", -10 }, /* Central Alaska */ + { "HST", -10 }, /* Hawaii Standard */ + { "HDT", -9 }, /* Hawaii Daylight */ + { "YDT", -8 }, /* Yukon Daylight */ + { "YST", -9 }, /* Yukon Standard */ + { "PST", -8 }, /* Pacific Standard */ + { "PDT", -7 }, /* Pacific Daylight */ + { "MST", -7 }, /* Mountain Standard */ + { "MDT", -6 }, /* Mountain Daylight */ + { "CST", -6 }, /* Central Standard */ + { "CDT", -5 }, /* Central Daylight */ + { "EST", -5 }, /* Eastern Standard */ + { "EDT", -4 }, /* Eastern Daylight */ + { "AST", -3 }, /* Atlantic Standard */ + { "ADT", -2 }, /* Atlantic Daylight */ + { "WAT", -1 }, /* West Africa */ + + { "GMT", 0 }, /* Greenwich Mean */ + { "UTC", 0 }, /* Universal (Coordinated) */ + + { "WET", 0 }, /* Western European */ + { "BST", 0 }, /* British Summer */ + { "CET", +1 }, /* Central European */ + { "MET", +1 }, /* Middle European */ + { "MEWT", +1 }, /* Middle European Winter */ + { "MEST", +2 }, /* Middle European Summer */ + { "CEST", +2 }, /* Central European Summer */ + { "MESZ", +1 }, /* Middle European Summer */ + { "FWT", +1 }, /* French Winter */ + { "FST", +2 }, /* French Summer */ + { "EET", +2 }, /* Eastern Europe, USSR Zone 1 */ + { "WAST", +7 }, /* West Australian Standard */ + { "WADT", +8 }, /* West Australian Daylight */ + { "CCT", +8 }, /* China Coast, USSR Zone 7 */ + { "JST", +9 }, /* Japan Standard, USSR Zone 8 */ + { "EAST", +10 }, /* Eastern Australian Standard */ + { "EADT", +11 }, /* Eastern Australian Daylight */ + { "GST", +10 }, /* Guam Standard, USSR Zone 9 */ + { "NZT", +11 }, /* New Zealand */ + { "NZST", +11 }, /* New Zealand Standard */ + { "NZDT", +12 }, /* New Zealand Daylight */ + { "IDLE", +12 }, /* International Date Line East */ +}; -static char *skipfws(char *str) +#define NR_TZ (sizeof(timezone_names) / sizeof(timezone_names[0])) + +static int match_string(const char *date, const char *str) { - while (isspace(*str)) - str++; - return str; + int i = 0; + + for (i = 0; *date; date++, str++, i++) { + if (*date == *str) + continue; + if (toupper(*date) == toupper(*str)) + continue; + if (!isalnum(*date)) + break; + return 0; + } + return i; } - -/* Gr. strptime is crap for this; it doesn't have a way to require RFC2822 - (i.e. English) day/month names, and it doesn't work correctly with %z. */ -void parse_date(char *date, char *result, int maxlen) +/* +* Parse month, weekday, or timezone name +*/ +static int match_alpha(const char *date, struct tm *tm, int *offset) { - struct tm tm; - char *p, *tz; - int i, offset; - time_t then; + int i; - memset(&tm, 0, sizeof(tm)); - - /* Skip day-name */ - p = skipfws(date); - if (!isdigit(*p)) { - for (i=0; i<7; i++) { - if (!strncmp(p,weekday_names[i],3) && p[3] == ',') { - p = skipfws(p+4); - goto day; - } + for (i = 0; i < 12; i++) { + int match = match_string(date, month_names[i]); + if (match >= 3) { + tm->tm_mon = i; + return match; } - return; - } - - /* day */ - day: - tm.tm_mday = strtoul(p, &p, 10); - - if (tm.tm_mday < 1 || tm.tm_mday > 31) - return; - - if (!isspace(*p)) - return; - - p = skipfws(p); + } - /* month */ + for (i = 0; i < 7; i++) { + int match = match_string(date, weekday_names[i]); + if (match >= 3) { + tm->tm_wday = i; + return match; + } + } - for (i=0; i<12; i++) { - if (!strncmp(p, month_names[i], 3) && isspace(p[3])) { - tm.tm_mon = i; - p = skipfws(p+strlen(month_names[i])); - goto year; + for (i = 0; i < NR_TZ; i++) { + int match = match_string(date, timezone_names[i].name); + if (match >= 3) { + *offset = 60*timezone_names[i].offset; + return match; } } - return; /* Error -- bad month */ - /* year */ - year: - tm.tm_year = strtoul(p, &p, 10); + /* BAD CRAP */ + return 0; +} - if (!tm.tm_year && !isspace(*p)) - return; +static int match_digit(char *date, struct tm *tm, int *offset) +{ + char *end, c; + unsigned long num, num2, num3; + + num = strtoul(date, &end, 10); + + /* Time? num:num[:num] */ + if (num < 24 && end[0] == ':' && isdigit(end[1])) { + tm->tm_hour = num; + num = strtoul(end+1, &end, 10); + if (num < 60) { + tm->tm_min = num; + if (end[0] == ':' && isdigit(end[1])) { + num = strtoul(end+1, &end, 10); + if (num < 61) + tm->tm_sec = num; + } + } + return end - date; + } - if (tm.tm_year > 1900) - tm.tm_year -= 1900; + /* Year? Day of month? Numeric date-string?*/ + c = *end; + switch (c) { + default: + if (num > 0 && num < 32) { + tm->tm_mday = num; + break; + } + if (num > 1900) { + tm->tm_year = num - 1900; + break; + } + if (num > 70) { + tm->tm_year = num; + break; + } + break; + + case '-': + case '/': + if (num && num < 32 && isdigit(end[1])) { + num2 = strtoul(end+1, &end, 10); + if (!num2 || num2 > 31) + break; + if (num > 12) { + if (num2 > 12) + break; + num3 = num; + num = num2; + num2 = num3; + } + tm->tm_mon = num - 1; + tm->tm_mday = num2; + if (*end == c && isdigit(end[1])) { + num3 = strtoul(end, &end, 10); + if (num3 > 1900) + num3 -= 1900; + tm->tm_year = num3; + } + break; + } + } - p=skipfws(p); - - /* hour */ - if (!isdigit(*p)) - return; - tm.tm_hour = strtoul(p, &p, 10); - - if (tm.tm_hour > 23) - return; - - if (*p != ':') - return; /* Error -- bad time */ - p++; - - /* minute */ - if (!isdigit(*p)) - return; - tm.tm_min = strtoul(p, &p, 10); - - if (tm.tm_min > 59) - return; - - if (*p != ':') - goto zone; - p++; - - /* second */ - if (!isdigit(*p)) - return; - tm.tm_sec = strtoul(p, &p, 10); - - if (tm.tm_sec > 60) - return; + return end - date; + +} - zone: - if (!isspace(*p)) - return; +static int match_tz(char *date, int *offp) +{ + char *end; + int offset = strtoul(date+1, &end, 10); + int min, hour; - p = skipfws(p); + min = offset % 100; + hour = offset / 100; - if (*p == '-') - offset = -60; - else if (*p == '+') - offset = 60; - else - return; + offset = hour*60+min; + if (*date == '-') + offset = -offset; - if (!isdigit(p[1]) || !isdigit(p[2]) || !isdigit(p[3]) || !isdigit(p[4])) - return; + *offp = offset; + return end - date; +} - tz = p; - i = strtoul(p+1, NULL, 10); - offset *= ((i % 100) + ((i / 100) * 60)); +/* Gr. strptime is crap for this; it doesn't have a way to require RFC2822 + (i.e. English) day/month names, and it doesn't work correctly with %z. */ +void parse_date(char *date, char *result, int maxlen) +{ + struct tm tm; + int offset; + time_t then; - p = skipfws(p + 5); - if (*p && *p != '(') /* trailing comment like (EDT) is ok */ - return; + memset(&tm, 0, sizeof(tm)); + tm.tm_year = -1; + tm.tm_mon = -1; + tm.tm_mday = -1; + offset = 0; + + for (;;) { + int match = 0; + unsigned char c = *date; + + /* Stop at end of string or newline */ + if (!c || c == '\n') + break; + + if (isalpha(c)) + match = match_alpha(date, &tm, &offset); + else if (isdigit(c)) + match = match_digit(date, &tm, &offset); + else if ((c == '-' || c == '+') && isdigit(date[1])) + match = match_tz(date, &offset); + + if (!match) { + /* BAD CRAP */ + match = 1; + } + + date += match; + } then = my_mktime(&tm); /* mktime uses local timezone */ if (then == -1) return; - then -= offset; + then -= offset * 60; - snprintf(result, maxlen, "%lu %5.5s", then, tz); + snprintf(result, maxlen, "%lu %+03d%02d", then, offset/60, offset % 60); } void datestamp(char *buf, int bufsize) diff --git a/test-date.c b/test-date.c new file mode 100644 index 000000000..8ec41c311 --- /dev/null +++ b/test-date.c @@ -0,0 +1,20 @@ +#include +#include + +#include "cache.h" + +int main(int argc, char **argv) +{ + int i; + + for (i = 1; i < argc; i++) { + char result[100]; + time_t t; + + memcpy(result, "bad", 4); + parse_date(argv[i], result, sizeof(result)); + t = strtoul(result, NULL, 0); + printf("%s -> %s -> %s\n", argv[i], result, ctime(&t)); + } + return 0; +} -- 2.30.2