new scanf implementation and corresponding integer parser/converter

advantages over the old code:
- correct results for floating point (old code was bogus)
- wide/regular scanf separated so scanf does not pull in wide code
- well-defined behavior on integers that overflow dest type
- support for %[a-b] ranges with %[ (impl-defined by widely used)
- no intermediate conversion of fmt string to wide string
- cleaner, easier to share code with strto* functions
- better standards conformance for corner cases

the old code remains in the source tree, as the wide versions of the
scanf-family functions are still using it. it will be removed when no
longer needed.

1 files changed, 8 insertions, 14 deletions

diff --git a/src/stdio/vsscanf.c b/src/stdio/vsscanf.c
index fd48f709..fbc15e69 100644
--- a/src/stdio/vsscanf.c
+++ b/src/stdio/vsscanf.c
@@ -1,21 +1,15 @@
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
+#include "stdio_impl.h"
 
-#include "__scanf.h"
-
-static void s_read(rctx_t *r)
+static size_t do_read(FILE *f, unsigned char *buf, size_t len)
 {
-	unsigned char *s = r->opaque;
-	if (!s[r->l]) r->c = -1;
-	else r->c = s[r->l++];
+	return __string_read(f, buf, len);
 }
 
 int vsscanf(const char *s, const char *fmt, va_list ap)
 {
-	size_t l = strlen(fmt), i;
-	wchar_t fmt2[l+1];
-	rctx_t r = { s_read, (void *)s, 0, isspace };
-	for (i=0; i<=l; i++) fmt2[i] = (unsigned char)fmt[i];
-	return __scanf(&r, fmt2, ap);
+	FILE f = {
+		.buf = (void *)s, .cookie = (void *)s,
+		.read = do_read, .lock = -1
+	};
+	return vfscanf(&f, fmt, ap);
 }