fmt changes from Google

src/lib9/testfltfmt.c

@@ -0,0 +1,166 @@
+#include <u.h>
+#include <libc.h>
+#include <stdio.h>
+
+/*
+ * try all combination of flags and float conversions
+ * with some different widths & precisions
+ */
+
+#define Njust 2
+#define Nplus 3
+#define Nalt 2
+#define Nzero 2
+#define Nspec 5
+#define Nwidth 5
+#define Nprec 5
+
+static double fmtvals[] = {
+	3.1415925535897932e15,
+	3.1415925535897932e14,
+	3.1415925535897932e13,
+	3.1415925535897932e12,
+	3.1415925535897932e11,
+	3.1415925535897932e10,
+	3.1415925535897932e9,
+	3.1415925535897932e8,
+	3.1415925535897932e7,
+	3.1415925535897932e6,
+	3.1415925535897932e5,
+	3.1415925535897932e4,
+	3.1415925535897932e3,
+	3.1415925535897932e2,
+	3.1415925535897932e1,
+	3.1415925535897932e0,
+	3.1415925535897932e-1,
+	3.1415925535897932e-2,
+	3.1415925535897932e-3,
+	3.1415925535897932e-4,
+	3.1415925535897932e-5,
+	3.1415925535897932e-6,
+	3.1415925535897932e-7,
+	3.1415925535897932e-8,
+	3.1415925535897932e-9,
+	3.1415925535897932e-10,
+	3.1415925535897932e-11,
+	3.1415925535897932e-12,
+	3.1415925535897932e-13,
+	3.1415925535897932e-14,
+	3.1415925535897932e-15,
+};
+
+/*
+ * are the numbers close?
+ * used to compare long numbers where the last few digits are garbage
+ * due to precision problems
+ */
+static int
+numclose(char *num1, char *num2)
+{
+	int ndig;
+	enum { MAXDIG = 15 };
+
+	ndig = 0;
+	while (*num1) {
+		if (*num1 >= '0' && *num1 <= '9') {
+			ndig++;
+			if (ndig > MAXDIG) {
+				if (!(*num2 >= '0' && *num2 <= '9')) {
+					return 0;
+				}
+			} else if (*num1 != *num2) {
+				return 0;
+			}
+		} else if (*num1 != *num2) {
+			return 0;
+		} else if (*num1 == 'e' || *num1 == 'E') {
+			ndig = 0;
+		}
+		num1++;
+		num2++;
+	}
+	if (*num1 || !num2)
+		return 0;
+	return 1;
+}
+
+static void
+doit(int just, int plus, int alt, int zero, int width, int prec, int spec)
+{
+	char format[256];
+	char *p;
+	const char *s;
+	int i;
+
+	p = format;
+	*p++ = '%';
+	if (just > 0)
+		*p++ = "-"[just - 1];
+	if (plus > 0)
+		*p++ = "+ "[plus - 1];
+	if (alt > 0)
+		*p++ = "#"[alt - 1];
+	if (zero > 0)
+		*p++ = "0"[zero - 1];
+
+	s = "";
+	switch (width) {
+	case 1: s = "1"; break;
+	case 2: s = "5"; break;
+	case 3: s = "10"; break;
+	case 4: s = "15"; break;
+	}
+	strcpy(p, s);
+
+	s = "";
+	switch (prec) {
+	case 1: s = ".0"; break;
+	case 2: s = ".2"; break;
+	case 3: s = ".5"; break;
+	case 4: s = ".15"; break;
+	}
+	strcat(p, s);
+
+	p = strchr(p, '\0');
+	*p++ = "efgEG"[spec];
+	*p = '\0';
+
+	for (i = 0; i < sizeof(fmtvals) / sizeof(fmtvals[0]); i++) {
+		char ref[256], buf[256];
+		Rune rbuf[256];
+
+		sprintf(ref, format, fmtvals[i]);
+		snprint(buf, sizeof(buf), format, fmtvals[i]);
+		if (strcmp(ref, buf) != 0
+		&& !numclose(ref, buf)) {
+			fprintf(stderr, "%s: ref='%s' fmt='%s'\n", format, ref, buf);
+			exit(1);
+		}
+
+		/* Check again with output to rune string */
+		runesnprint(rbuf, 256, format, fmtvals[i]);
+		snprint(buf, sizeof(buf), "%S", rbuf);
+		if (strcmp(ref, buf) != 0
+		&& !numclose(ref, buf)) {
+			fprintf(stderr, "%s: rune ref='%s' fmt='%s'\n", format, ref, buf);
+			exits("oops");
+		}
+	}
+}
+
+void
+main(int argc, char **argv)
+{
+	int just, plus, alt, zero, width, prec, spec;
+
+	for (just = 0; just < Njust; just++)
+	for (plus = 0; plus < Nplus; plus++)
+	for (alt = 0; alt < Nalt; alt++)
+	for (zero = 0; zero < Nzero; zero++)
+	for (width = 0; width < Nwidth; width++)
+	for (prec = 0; prec < Nprec; prec++)
+	for (spec = 0; spec < Nspec; spec++)
+		doit(just, plus, alt, zero, width, prec, spec);
+
+	exits(0);
+}