musl/src/stdio/vsscanf.c

#include "stdio_impl.h"
#include "libc.h"

static size_t do_read(FILE *f, unsigned char *buf, size_t len)
{
	return __string_read(f, buf, len);
}

int vsscanf(const char *restrict s, const char *restrict fmt, va_list ap)
{
	FILE f = {
		.buf = (void *)s, .cookie = (void *)s,
		.read = do_read, .lock = -1
	};
	return vfscanf(&f, fmt, ap);
}

weak_alias(vsscanf,__isoc99_vsscanf);
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. 2012-04-16 16:03:45 -04:00			`#include "stdio_impl.h"`
Add ABI compatability aliases. GNU used several extensions that were incompatible with C99 and POSIX, so they used alternate names for the standard functions. The result is that we need these to run standards-conformant programs that were linked with glibc. 2013-04-05 23:20:28 -07:00			`#include "libc.h"`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00
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. 2012-04-16 16:03:45 -04:00			`static size_t do_read(FILE f, unsigned char buf, size_t len)`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`{`
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. 2012-04-16 16:03:45 -04:00			`return __string_read(f, buf, len);`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`}`

use restrict everywhere it's required by c99 and/or posix 2008 to deal with the fact that the public headers may be used with pre-c99 compilers, __restrict is used in place of restrict, and defined appropriately for any supported compiler. we also avoid the form [restrict] since older versions of gcc rejected it due to a bug in the original c99 standard, and instead use the form *restrict. 2012-09-06 22:44:55 -04:00			`int vsscanf(const char restrict s, const char restrict fmt, va_list ap)`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`{`
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. 2012-04-16 16:03:45 -04:00			`FILE f = {`
			`.buf = (void )s, .cookie = (void )s,`
			`.read = do_read, .lock = -1`
			`};`
			`return vfscanf(&f, fmt, ap);`
initial check-in, version 0.5.0 2011-02-12 00:22:29 -05:00			`}`
Add ABI compatability aliases. GNU used several extensions that were incompatible with C99 and POSIX, so they used alternate names for the standard functions. The result is that we need these to run standards-conformant programs that were linked with glibc. 2013-04-05 23:20:28 -07:00
			`weak_alias(vsscanf,__isoc99_vsscanf);`