Approxidate

Taken from Linus' original code in /git/date.c, approxidate gives you a dead-simple way to get a timestamp from tons of date formats. Unlike git's original approxidate, this approxidate also returns microseconds.

Usage

There are two functions:

/**
 * Get a unix timestamp from an arbitrary date string.
 *
 * If the given date string is missing any parts (date, time, etc), those parts
 * will be filled in from the current time.
 *
 * Returns -1 on parse failure, 0 on success.
 */
int approxidate(const char* date, struct timeval* tv);

/**
 * Get a unix timestamp from an arbitrary date string.
 *
 * Functions much like approxidate, except that if the given date string is
 * missing any parts (date, time, etc), those parts will be filled in from the
 * relative_to value; if relative_to is NULL, then now is used.
 *
 * Returns -1 on parse failure, 0 on success.
 */
int approxidate_relative(
	const char*           date,
	struct timeval*       tv,
	const struct timeval* relative_to);

When compiling, copy both approxidate.{c,h} to your project, link in the math library (-lm), and you're good.

#include <approxidate.h>

struct timeval t;
approxidate("10/Mar/2013:12:43:02.603 -0500", &t);
approxidate("10/Mar/2013:12:43:02 -0500", &t);

Note: If no timezone is given, the system's local timezone is used.

For more examples, check out approxidate-test.c.

Speed

From approxidate-test.c (for 1,000,000 iterations):

$ make test
...
approxidate time: 0.144372
strptime time: 0.624939

Python

Check out: https://pypi.python.org/pypi/approxidate