X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fstdio%2Fvfprintf.c;h=31c3d5ddca8f78fc5f8dedf3e6801ab2688433d9;hb=6739b13a172aad9c01572c04cadacc99c7041811;hp=d186d58b5e1530855bf8d5aca388bb56ad658194;hpb=2b964b010e5d37cb2ff712d57a14095188d689e3;p=musl

diff --git a/src/stdio/vfprintf.c b/src/stdio/vfprintf.c
index d186d58b..31c3d5dd 100644
--- a/src/stdio/vfprintf.c
+++ b/src/stdio/vfprintf.c
@@ -1,4 +1,13 @@
 #include "stdio_impl.h"
+#include <errno.h>
+#include <ctype.h>
+#include <limits.h>
+#include <string.h>
+#include <stdarg.h>
+#include <wchar.h>
+#include <inttypes.h>
+#include <math.h>
+#include <float.h>
 
 /* Some useful macros */
 
@@ -189,9 +198,17 @@ static char *fmt_u(uintmax_t x, char *s)
 	return s;
 }
 
+/* Do not override this check. The floating point printing code below
+ * depends on the float.h constants being right. If they are wrong, it
+ * may overflow the stack. */
+#if LDBL_MANT_DIG == 53
+typedef char compiler_defines_long_double_incorrectly[9-(int)sizeof(long double)];
+#endif
+
 static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
 {
-	uint32_t big[(LDBL_MAX_EXP+LDBL_MANT_DIG)/9+1];
+	uint32_t big[(LDBL_MANT_DIG+28)/29 + 1          // mantissa expansion
+		+ (LDBL_MAX_EXP+LDBL_MANT_DIG+28+8)/9]; // exponent expansion
 	uint32_t *a, *d, *r, *z;
 	int e2=0, e, i, j, l;
 	char buf[9+LDBL_MANT_DIG/4], *s;
@@ -200,7 +217,7 @@ static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
 	char ebuf0[3*sizeof(int)], *ebuf=&ebuf0[3*sizeof(int)], *estr;
 
 	pl=1;
-	if (y<0 || 1/y<0) {
+	if (signbit(y)) {
 		y=-y;
 	} else if (fl & MARK_POS) {
 		prefix+=3;
@@ -297,7 +314,7 @@ static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
 	}
 	while (e2<0) {
 		uint32_t carry=0, *b;
-		int sh=MIN(9,-e2);
+		int sh=MIN(9,-e2), need=1+(p+LDBL_MANT_DIG/3+8)/9;
 		for (d=a; d<z; d++) {
 			uint32_t rm = *d & (1<<sh)-1;
 			*d = (*d>>sh) + carry;
@@ -307,7 +324,7 @@ static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
 		if (carry) *z++ = carry;
 		/* Avoid (slow!) computation past requested precision */
 		b = (t|32)=='f' ? r : a;
-		if (z-b > 2+p/9) z = b+2+p/9;
+		if (z-b > need) z = b+need;
 		e2+=sh;
 	}
 
@@ -514,7 +531,6 @@ static int printf_core(FILE *f, const char *fmt, va_list *ap, union arg *nl_arg,
 		/* Check validity of argument type (nl/normal) */
 		if (st==NOARG) {
 			if (argpos>=0) return -1;
-			else if (!f) continue;
 		} else {
 			if (argpos>=0) nl_type[argpos]=st, arg=nl_arg[argpos];
 			else if (f) pop_arg(&arg, st, ap);
@@ -636,7 +652,7 @@ static int printf_core(FILE *f, const char *fmt, va_list *ap, union arg *nl_arg,
 	return 1;
 }
 
-int vfprintf(FILE *f, const char *fmt, va_list ap)
+int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap)
 {
 	va_list ap2;
 	int nl_type[NL_ARGMAX+1] = {0};
@@ -644,8 +660,12 @@ int vfprintf(FILE *f, const char *fmt, va_list ap)
 	unsigned char internal_buf[80], *saved_buf = 0;
 	int ret;
 
+	/* the copy allows passing va_list* even if va_list is an array */
 	va_copy(ap2, ap);
-	if (printf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) return -1;
+	if (printf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) {
+		va_end(ap2);
+		return -1;
+	}
 
 	FLOCK(f);
 	if (!f->buf_size) {