/*

Illustration of glibc's scanf accepting numeric strings as valid even though
they are missing required digits.  The problem affects both hexadecimal integer
and floating point conversions.

$ diff -u glibc uClibc       
--- glibc       2003-08-16 19:31:23.000000000 -0500
+++ uClibc      2003-08-16 19:31:22.000000000 -0500
@@ -1,7 +1,7 @@
-count=2  n=3  quant=0.000000  buf="!"
-count=2  n=5  quant=0.000000  buf="!"
-count=2  n=3  quant=0.000000  buf="!"
-count=2  n=4  quant=0.000000  buf="!"
-count=2  n=5  quant=0.000000  buf="!"
-count=2  n=2  iquant=0  buf="!"
-count=1  n=2  iquant=0  buf="?????????"
+count=0  n=-1  quant=nan  buf="?????????"
+count=0  n=-1  quant=nan  buf="?????????"
+count=0  n=-1  quant=nan  buf="?????????"
+count=0  n=-1  quant=nan  buf="?????????"
+count=0  n=-1  quant=nan  buf="?????????"
+count=0  n=-1  iquant=-2147483648  buf="?????????"
+count=2  n=1  iquant=0  buf="x"

*/

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <limits.h>
#include <locale.h>
#include <wchar.h>

int main(void)
{
	FILE *fp;
	float quant;
	int count, n, iquant;
	char buf[10];

	static char membuf[] =
		"0xp!\n"
		"0xp-!\n"
		"0e!\n"
		".0e!\n"
		".0e+!\n"
		;

	if (!(fp = fmemopen(membuf, sizeof(membuf)-1, "r"))) { /* omit trailing nul */
		printf("fmemopen failed\n");
		return EXIT_FAILURE;
	}

	do {
		quant = 0./0.;
		n = -1;
		memset(buf, '?', sizeof(buf)); buf[sizeof(buf)-1] = 0;
		count = fscanf(fp, "%f%n%s", &quant, &n, buf);
		if (ferror(fp)) {
			printf("stream error indicator is set!\n");
			fclose(fp);
			return EXIT_FAILURE;
		}
		if (feof(fp)) {
			fclose(fp);
			break;
		}
		printf("count=%d  n=%d  quant=%f  buf=\"%s\"\n",
			   count, n, quant, buf);
		fscanf(fp,"%*[^\n]");
	} while (1);

	iquant = INT_MIN;
	n = -1;
	memset(buf, '?', sizeof(buf)); buf[sizeof(buf)-1] = 0;
	count = sscanf("0x!", "%x%n%s", &iquant, &n, buf);
	printf("count=%d  n=%d  iquant=%d  buf=\"%s\"\n",
		   count, n, iquant, buf);

	iquant = INT_MIN;
	n = -1;
	memset(buf, '?', sizeof(buf)); buf[sizeof(buf)-1] = 0;
	count = sscanf("0x", "%x%n%s", &iquant, &n, buf);
	printf("count=%d  n=%d  iquant=%d  buf=\"%s\"\n",
		   count, n, iquant, buf);

	return EXIT_SUCCESS;
}