#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>

#include "eprintf.h"

char *pname;

/* eprintf: print error and exit, a trailing : in fmt prints strerror(errno) */
void eprintf(const char *fmt, ...)
{
	int errnum = errno;
	va_list va;

	if (progname() != NULL)
		fprintf(stderr, "%s: ", progname());

	va_start(va, fmt);
	vfprintf(stderr, fmt, va);
	va_end(va);

	if (fmt[0] != '\0' && fmt[strlen(fmt) - 1] == ':')
		fprintf(stderr, " %s", strerror(errnum));
	fputc('\n', stderr);

	exit(EXIT_FAILURE);
}

/* weprintf: print warning, a trailing : in fmt prints strerror(errno) */
void weprintf(const char *fmt, ...)
{
	int errnum = errno;
	va_list va;

	if (progname() != NULL)
		fprintf(stderr, "%s: ", progname());

	va_start(va, fmt);
	vfprintf(stderr, fmt, va);
	va_end(va);

	if (fmt[0] != '\0' && fmt[strlen(fmt) - 1] == ':')
		fprintf(stderr, " %s", strerror(errnum));
	fputc('\n', stderr);
}

/* estrdup: attempt to strdup a string or exit on error */
char *estrdup(const char *s)
{
	size_t len;
	char *dup;

	len = strlen(s);
	if (len == SIZE_MAX)
		eprintf("estrdup(\"%.20s\") failed: Too long", s);
	dup = malloc(len + 1);
	if (dup == NULL)
		eprintf("estrdup(\"%.20s\") failed:", s);
	strcpy(dup, s);

	return dup;
}

/* emalloc: attempt to allocate memory or exit on error */
void *emalloc(size_t n)
{
	void *p;

	p = malloc(n);
	if (p == NULL)
		eprintf("emalloc(%zu) failed:", n);

	return p;
}

/* ecalloc: attempt to allocate memory or exit on error */
void *ecalloc(size_t nmemb, size_t size)
{
	void *p;

	p = calloc(nmemb, size);
	if (p == NULL)
		eprintf("ecalloc(%zu, %zu) failed:", nmemb, size);

	return p;
}

/* erealloc: attempt to reallocate memory or exit on error */
void *erealloc(void *p, size_t n)
{
	void *r;

	r = realloc(p, n);
	if (r == NULL)
		eprintf("erealloc(%p, %zu) failed:", p, n);

	return r;
}

/* progname: retrieve stored name of program */
char *progname(void)
{
	return pname;
}

/* setprogname: set stored name of program */
void setprogname(const char *s)
{
	if (pname != NULL) {
		weprintf("setprogname(\"%.20s\") called more than once", s);
		return;
	}

	pname = estrdup(s);
}