com32/lib/strerror.c


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/*
 * strerror.c
 */

#include <string.h>

char *strerror(int errnum)
{
	static char message[32] = "error ";	/* enough for error 2^63-1 */
	char numbuf[32];
	char *p;
	unsigned int e = (unsigned int)errnum;

	extern const int sys_nerr;
	extern const char *const sys_errlist[];

	if (e < (unsigned int)sys_nerr && sys_errlist[e])
		return (char *)sys_errlist[e];

	p = numbuf + sizeof numbuf;
	*--p = '\0';

	do {
		*--p = (e % 10) + '0';
		e /= 10;
	} while (e);

	memcpy(message + 6, p, (numbuf + sizeof numbuf) - p);

	return message;
}