[PATCH 27/32] tools/nolibc: add snprintf() and friends

From: Thomas Weißschuh
Date: Tue Mar 04 2025 - 02:16:53 EST


Add more of the printf() functions.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
---
tools/include/nolibc/stdio.h | 55 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 55 insertions(+)

diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h
index b484a19466394d55d7d21248031837238b58f3ff..e9f9cb2e8d9877221b442f9f3757d7ace1a5538c 100644
--- a/tools/include/nolibc/stdio.h
+++ b/tools/include/nolibc/stdio.h
@@ -389,6 +389,61 @@ int dprintf(int fd, const char *fmt, ...)
va_start(args, fmt);
ret = vdprintf(fd, fmt, args);
va_end(args);
+
+ return ret;
+}
+
+static int _sprintf_cb(intptr_t _state, const char *buf, size_t size)
+{
+ char **state = (char **)_state;
+
+ memcpy(*state, buf, size);
+ *state += size;
+ return 0;
+}
+
+static __attribute__((unused, format(printf, 3, 0)))
+int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
+{
+ char *state = buf;
+ int ret;
+
+ ret = _printf(_sprintf_cb, (intptr_t)&state, size, fmt, args);
+ if (ret < 0)
+ return ret;
+ buf[(size_t)ret < size ? (size_t)ret : size - 1] = '\0';
+ return ret;
+}
+
+static __attribute__((unused, format(printf, 3, 4)))
+int snprintf(char *buf, size_t size, const char *fmt, ...)
+{
+ va_list args;
+ int ret;
+
+ va_start(args, fmt);
+ ret = vsnprintf(buf, size, fmt, args);
+ va_end(args);
+
+ return ret;
+}
+
+static __attribute__((unused, format(printf, 2, 0)))
+int vsprintf(char *buf, const char *fmt, va_list args)
+{
+ return vsnprintf(buf, SIZE_MAX, fmt, args);
+}
+
+static __attribute__((unused, format(printf, 2, 3)))
+int sprintf(char *buf, const char *fmt, ...)
+{
+ va_list args;
+ int ret;
+
+ va_start(args, fmt);
+ ret = vsprintf(buf, fmt, args);
+ va_end(args);
+
return ret;
}


--
2.48.1