ccan/ccan/pushpull/_info

#include "config.h"
#include <stdio.h>
#include <string.h>

/**
 * pushpull - simple marshalling/unmarshalling routines
 *
 * This code lets you clearly add simple types into a buffer (the push
 * functions) and remove them (the pull functions).  The buffer stores
 * the values as little-endian for machine portability.  The pull functions
 * don't need to be checked on every call, but error state is kept so you
 * can check if there was an error at the end.
 *
 * The normal way to use this is to create your own higher-level marshal
 * and unmarshal functions in terms of these.
 *
 * Author: Rusty Russell <rusty@rustcorp.com.au>
 * License: CC0 (Public domain)
 *
 * Example:
 *	#include <ccan/pushpull/push.h>
 *	#include <ccan/pushpull/pull.h>
 *	#include <ccan/err/err.h>
 *	#include <string.h>
 *	#include <stdio.h>
 *	#include <unistd.h>
 *
 *	int main(int argc, char *argv[])
 *	{
 *		if (argv[1] && !strcmp(argv[1], "push")) {
 *			int i;
 *			char *buf = malloc(1);
 *			size_t len = 0;
 *
 *			// We ignore allocation failure!
 *			for (i = 2; i < argc; i++)
 *				push_u32(&buf, &len, atol(argv[i]));
 *
 *			write(STDOUT_FILENO, buf, len);
 *		} else if (argc == 2 && !strcmp(argv[1], "pull")) {
 *			int r, max = 32;
 *			size_t len = 0;
 *			char *buf = malloc(max);
 *			const char *p;
 *			uint32_t val;
 *
 *			while ((r = read(STDIN_FILENO, buf+len, max-len)) > 0) {
 *				len += r;
 *				if (len == max) {
 *					max *= 2;
 *					// We crash on allocation failure
 *					buf = realloc(buf, max);
 *				}
 *			}
 *
 *			p = buf;
 *			while (pull_u32(&p, &len, &val))
 *				printf("%u ", val);
 *		} else
 *			errx(1, "Usage: %s [push|pull] [<number>...]", argv[0]);
 *		return 0;
 *	}
 */
int main(int argc, char *argv[])
{
	/* Expect exactly one argument */
	if (argc != 2)
		return 1;

	if (strcmp(argv[1], "depends") == 0) {
		printf("ccan/endian\n");
		return 0;
	}

	return 1;
}