1 files changed, 46 insertions, 0 deletions
diff --git a/lib/libc/stdio/fmemopen.c b/lib/libc/stdio/fmemopen.c
new file mode 100644
index 00000000..1ad86f7b
--- /dev/null
+++ b/lib/libc/stdio/fmemopen.c
@@ -0,0 +1,46 @@
+#include <io.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <libc.h>
+
+weak void __stdio_cleanup(void)
+{
+}
+
+FILE *fmemopen(void *restrict buf, size_t max_size, const char *restrict mode)
+{
+	int flags;
+	FILE *f = calloc(1, sizeof(FILE));
+
+	if (f == NULL)
+		return f;
+
+	f->fd = -1;
+	f->buf = buf;
+	f->buf_size = max_size;
+	f->type = _IOFBF;
+
+	if (mode[0] == 'r') {
+		flags = O_RDONLY;
+	} else if (mode[0] == 'w') {
+		flags = O_WRONLY | O_CREAT | O_TRUNC;
+	} else if (mode[0] == 'a') {
+		flags = O_WRONLY | O_CREAT | O_APPEND;
+	} else {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (strchr(mode, '+')) {
+		flags = (flags & ~(O_RDONLY | O_WRONLY)) | O_RDWR;
+	}
+
+	f->flags = flags;
+
+	__libc_fadd(f);
+
+	return f;
+}