From: Radu Nichita <radunichita99@gmail.com>
Date: Wed, 12 Jul 2023 22:47:09 +0000 (+0300)
Subject: lib/nolibc: scanf and fscanf functions
X-Git-Tag: RELEASE-0.14.0~221
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=e622c0043f505b83d81e88c70d42ba6ae7514dac;p=unikraft%2Funikraft.git

lib/nolibc: scanf and fscanf functions

Adding scanf and fscanf function to nolibc, since their symbols were
exported, but no implementation was provided.

Signed-off-by: Radu Nichita <radunichita99@gmail.com>
Reviewed-by: Adina-Maria Vaman <adinamaariav22@gmail.com>
Approved-by: Razvan Deaconescu <razvand@unikraft.io>
Tested-by: Unikraft CI <monkey@unikraft.io>
GitHub-Closes: #977
---

diff --git a/lib/nolibc/Makefile.uk b/lib/nolibc/Makefile.uk
index 3efeba4bf..82a22f716 100644
--- a/lib/nolibc/Makefile.uk
+++ b/lib/nolibc/Makefile.uk
@@ -44,6 +44,7 @@ LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/musl-imported/src/network/ntohs.c
 LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/h_errno.c
 LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/getopt.c
 LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/sscanf.c
+LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/scanf.c
 LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/asprintf.c
 LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/random.c
 
diff --git a/lib/nolibc/exportsyms.uk b/lib/nolibc/exportsyms.uk
index c90f452e8..1307f77cd 100644
--- a/lib/nolibc/exportsyms.uk
+++ b/lib/nolibc/exportsyms.uk
@@ -22,8 +22,9 @@ free
 
 # sscanf
 vsscanf
-scanf
 sscanf
+scanf
+fscanf
 
 # stdio
 stdin
diff --git a/lib/nolibc/include/stdio.h b/lib/nolibc/include/stdio.h
index 1e5f9f2aa..e84a38221 100644
--- a/lib/nolibc/include/stdio.h
+++ b/lib/nolibc/include/stdio.h
@@ -78,6 +78,9 @@ int  printf(const char *fmt, ...)                           __printf(1, 2);
 int vsscanf(const char *str, const char *fmt, va_list ap);
 int  sscanf(const char *str, const char *fmt, ...)          __scanf(2, 3);
 
+int scanf(const char *fmt, ...);                            __scanf(1, 2);
+int fscanf(FILE *fp, const char *fmt, ...);                 __scanf(2, 3); 
+
 int vasprintf(char **str, const char *fmt, va_list ap);
 int  asprintf(char **str, const char *fmt, ...)             __printf(2, 3);
 
diff --git a/lib/nolibc/scanf.c b/lib/nolibc/scanf.c
new file mode 100644
index 000000000..b07df6420
--- /dev/null
+++ b/lib/nolibc/scanf.c
@@ -0,0 +1,102 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/* Copyright (c) 2023, Unikraft GmbH and The Unikraft Authors.
+ * Licensed under the BSD-3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ */
+
+#include <stdio.h>
+#include <stdarg.h>
+
+#include <uk/plat/console.h>
+
+static int
+uk_scanf(void *buffer,  size_t *cnt)
+{
+	int bytes_read;
+	size_t bytes_total = 0, count;
+	char *buf = buffer;
+
+	count = *cnt;
+
+	do {
+		while ((bytes_read = ukplat_cink(buf,
+			count - bytes_total)) <= 0)
+			;
+
+		buf = buf + bytes_read;
+		*(buf - 1) = *(buf - 1) == '\r' ?
+					'\n' : *(buf - 1);
+
+		/* Echo the input */
+		if (*(buf - 1) == '\177') {
+			/* DELETE control character */
+			if (buf - 1 != buffer) {
+				/* If this is not the first byte */
+				ukplat_coutk("\b \b", 3);
+				buf -= 1;
+				if (bytes_total > 0)
+					bytes_total--;
+			}
+			buf -= 1;
+		} else {
+			ukplat_coutk(buf - bytes_read, bytes_read);
+			bytes_total += bytes_read;
+		}
+
+	} while (bytes_total < count &&
+	((bytes_total == 0) || (*(buf - 1) != '\n' && *(buf - 1) != '\0')));
+
+	*cnt = bytes_total;
+
+	return 0;
+}
+
+int
+vfscanf(FILE *fp, const char *fmt, va_list ap)
+{
+	int ret = 0;
+	char buf[1024];
+	size_t size = sizeof(buf);
+
+	if (fp == stdin)
+		ret = uk_scanf(buf, &size);
+	else
+		return 0;
+
+	if (ret < 0)
+		return ret;
+
+	ret = vsscanf(buf, fmt, ap);
+	return ret;
+}
+
+int
+vscanf(const char *fmt, va_list ap)
+{
+	return vfscanf(stdin, fmt, ap);
+}
+
+int
+fscanf(FILE *fp, const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+
+	va_start(ap, fmt);
+	ret = vfscanf(fp, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+int
+scanf(const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+
+	va_start(ap, fmt);
+	ret = vscanf(fmt, ap);
+	va_end(ap);
+	return ret;
+}