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 3efeba4bf825536e92d0f7dd7e3acd075a18088b..82a22f716d67725084cc628b1f867da4999f8826 100644 (file)
--- 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 c90f452e81a1fbdb9f8bbd06a36b5245a39047cb..1307f77cde870149087755abb540c587845cbe45 100644 (file)
--- 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 1e5f9f2aa1f0ab60ca17b291712138161671c4b2..e84a3822107b6e2b36070dc680c257a8358eae7a 100644 (file)
--- 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 (file)
index 0000000..b07df64
--- /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;
+}